Randomised clinical trial: efficacy of Lactobacillus paracasei-enriched artichokes in the treatment of patients with functional constipation--a double-blind, controlled, crossover study

Between Dysbiosis, Maternal Immune Activation and Autism: Is There a Common Pathway?

Autism spectrum disorder (ASD) is a neuropsychiatric condition characterized by impaired social interactions and repetitive stereotyped behaviors. Growing evidence highlights an important role of the gut-brain-microbiome axis in the pathogenesis of ASD. Research indicates an abnormal composition of the gut microbiome and the potential involvement of bacterial molecules in neuroinflammation and brain development disruptions. Concurrently, attention is directed towards the role of short-chain fatty acids (SCFAs) and impaired intestinal tightness. This comprehensive review emphasizes the potential impact of maternal gut microbiota changes on the development of autism in children, especially considering maternal immune activation (MIA). The following paper evaluates the impact of the birth route on the colonization of the child with bacteria in the first weeks of life. Furthermore, it explores the role of pro-inflammatory cytokines, such as IL-6 and IL-17a and mother's obesity as potentially environmental factors of ASD. The purpose of this review is to advance our understanding of ASD pathogenesis, while also searching for the positive implications of the latest therapies, such as probiotics, prebiotics or fecal microbiota transplantation, targeting the gut microbiota and reducing inflammation. This review aims to provide valuable insights that could instruct future studies and treatments for individuals affected by ASD.

Lactobacillus paracasei Relieves Constipation by Acting on the Acetic Acid-5-HT-Intestinal Motility Pathway

Constipation is a major health concern worldwide and requires effective and safe treatment options. In this study, we selected ten strains of two species of lactobacilli to identify whether they were effective against constipation induced by loperamide administration in BALB/c mice. Monitoring of constipation-related indicators indicated that Lactobacillus paracasei (L. paracasei) mainly acted on the whole intestinal peristalsis to relieve constipation. Furthermore, through the detection of biological, chemical, mechanical, and immune barriers in mice, it was discovered that L. paracasei changed the relative abundance of bacteria related to the levels of acetic acid and 5-hydroxytryptamine (5-HT) (such as by increasing the relative abundance of Odoribacter and Clostridium, and reducing the relative abundance of Mucispirillum, Ruminococcus, Coprobacillus, and Dorea), increased the concentration of acetic acid in the intestine, which stimulated enterochromaffin cells, promoted 5-HT synthesis in the colon, enhanced intestinal motility, and relieved constipation. In conclusion, this study provides a theoretical foundation for the development of personalized products for the treatment of constipation.

Effect of Bacillus coagulans Unique IS2 with Lactulose on Functional Constipation in Adults: a Double-Blind Placebo Controlled Study

In the present double-blind randomised study, the efficacy of combination of Bacillus coagulans Unique IS2 and lactulose was evaluated in the treatment of functional constipation in adults. One-fifty participants diagnosed with functional constipation (Rome III criteria) were randomised (1:1:1) and supplemented daily with 15 mL suspension of probiotic (B. coagulans Unique IS2, 2 × 10⁹ spores) with lactulose (10 g) (group 1) or lactulose (10 g) (group 2) or placebo (water) (group 3) for 4 weeks. The primary (stool frequency) and secondary outome measures (stool consistency, sensation of incomplete evacuation, defecation- and abdominal-pain) were recorded weekly for up to 4 weeks. Bacillus coagulans Unique IS2 with lactulose showed significant changes in stool frequency as compared to lactulose treatment; however, at the end of the trial, it was found insignificant due to the gradual increase of stool frequency score of lactulose treatment. The changes observed in stool consistency were early (2nd week) and remained consistent up to end of the trial. The significant reduction of sensation of incomplete evacuation, defecation-, and abdominal-pain correlated with the strains ability to produce short-chain fatty acids. No adverse events were observed in any of the groups, and all the vital parameters were normal during the course of the study. Overall, results indicated that B. coagulans Unique IS2 addition to lactulose reduced time required to relieve constipation as compared to lactulose alone. In conclusion, B. coagulans Unique IS2 with lactulose is more effective than lactulose alone to relieve symptoms of constipation in a shorter period. Trial registration: CTRI/2018/11/016399, dated 22/11/2018.

Electrospinning Living Bacteria: A Review of Applications from Agriculture to Health Care

Living bacteria are used in biotechnologies that lead to improvements in health care, agriculture, and energy. Encapsulating bacteria into flexible and modular electrospun polymer fabrics that maintain their viability will further enable their use. This review will first provide a brief overview of electrospinning before examining the impact of electrospinning parameters, such as precursor composition, applied voltage, and environment on the viability of encapsulated bacteria. Currently, the use of nanofiber scaffolds to deliver live probiotics into the gut is the most researched application space; however, several additional applications, including skin probiotics (wound bandages) and menstruation products have also been explored and will be discussed. The use of bacteria-loaded nanofibers as seed coatings that promote plant growth, for the remediation of contaminated wastewaters, and in energy-generating microbial fuel cells are also covered in this review. In summary, electrospinning is an effective method for encapsulating living microorganisms into dry polymer nanofibers. While these living composite scaffolds hold potential for use across many applications, before their use in commercial products can be realized, numerous challenges and further investigations remain.

Bifidobacterium bifidum CCFM1163 Alleviated Cathartic Colon by Regulating the Intestinal Barrier and Restoring Enteric Nerves

Cathartic colon (CC), a type of slow-transit constipation caused by the long-term use of stimulant laxatives, does not have a precise and effective treatment. This study aimed to evaluate the ability of Bifidobacterium bifidum CCFM1163 to relieve CC and to investigate its underlying mechanism. Male C57BL/6J mice were treated with senna extract for 8 weeks, followed by a 2-week treatment with B. bifidum CCFM1163. The results revealed that B. bifidum CCFM1163 effectively alleviated CC symptoms. The possible mechanism of B. bifidum CCFM1163 in relieving CC was analyzed by measuring the intestinal barrier and enteric nervous system (ENS)-related indices and establishing a correlation between each index and gut microbiota. The results indicated that B. bifidum CCFM1163 changed the gut microbiota by significantly increasing the relative abundance of Bifidobacterium, Faecalibaculum, Romboutsia, and Turicibacter as well as the content of short-chain fatty acids, especially propionic acid, in the feces. This increased the expression of tight junction proteins and aquaporin 8, decreased intestinal transit time, increased fecal water content, and relieved CC. In addition, B. bifidum CCFM1163 also increased the relative abundance of Faecalibaculum in feces and the expression of enteric nerve marker proteins to repair the ENS, promote intestinal motility, and relieve constipation.

Probiotics, prebiotics, and synbiotics in chronic constipation: Outstanding aspects to be considered for the current evidence

This integrative aimed to evaluate the effects and the potential mechanism of action of prebiotics, probiotics, and synbiotics on constipation-associated gastrointestinal symptoms and to identify issues that still need to be answered. A literature search was performed in the PubMed database. Animal models (n = 23) and clinical trials (n = 39) were included. In animal studies, prebiotic, probiotic, and synbiotic supplementation showed a decreased colonic transit time (CTT) and an increase in the number and water content of feces. In humans, inulin is shown to be the most promising prebiotic, while B. lactis and L. casei Shirota probiotics were shown to increase defecation frequency, the latter strain being more effective in improving stool consistency and constipation symptoms. Overall, synbiotics seem to reduce CTT, increase defecation frequency, and improve stool consistency with a controversial effect on the improvement of constipation symptoms. Moreover, some aspects of probiotic use in constipation-related outcomes remain unanswered, such as the best dose, duration, time of consumption (before, during, or after meals), and matrices, as well as their effect and mechanisms on the regulation of inflammation in patients with constipation, on polymorphisms associated with constipation, and on the management of constipation via 5-HT. Thus, more high-quality randomized control trials (RCTs) evaluating these lacking aspects are necessary to provide safe conclusions about their effectiveness in managing intestinal constipation.

Cannabis sativa L. alleviates loperamide-induced constipation by modulating the composition of gut microbiota in mice

MaZiRenWan (MZRW) is the most frequently used Traditional Chinese Medicine formula to treat chronic constipation, Cannabis sativa L. is regarded as a monarch drug in MZRW. However, the targets of Cannabis sativa L. that enhance colonic motility and improve constipation symptoms remain unknown. This study was designed to investigate the laxative effect and underlying mechanism of the water extract of Cannabis sativa L. (WECSL) using a loperamide-induced constipation mouse model. We found that WECSL treatment significantly improved intestinal motility and water-electrolyte metabolism, decreased inflammatory responses, prevented gut barrier damage, and relieved anxiety and depression in constipated mice. WECSL also structurally remodeled the composition of the gut microbiota and altered the abundance of bacteria related to inflammation, specifically Butyricicoccus and Parasutterella. Moreover, WECSL failed to relieve constipation symptoms following intestinal flora depletion, indicating that WECSL alleviates constipation symptoms depending on the gut microbiota. Our research provides a basis for WECSL to be further investigated in the treatment of constipation from the perspective of modern medicine.

Probiotics and synbiotics in chronic constipation in adults: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND & AIMS

Probiotics and synbiotics have been increasingly investigated for the management of chronic constipation. We aimed to investigate the effect of probiotics and synbiotics on stool output, gut transit time, symptoms and quality of life in adults with chronic constipation via a systematic review and meta-analysis of randomized controlled trials (RCTs).

METHODS

Studies were identified using electronic databases, backward citation and hand-searching abstracts. The search date was 10 July 2022. RCTs reporting administration of probiotics or synbiotics in adults with chronic constipation were included. Risk of bias (RoB) was assessed with the Cochrane RoB 2.0 tool. Meta-analysis was conducted separately for probiotics and synbiotics. Results were synthesized using risk ratios (RRs), mean differences or standardized mean differences (SMDs) and 95% confidence intervals (CIs) using a random-effects model.

RESULTS

Thirty RCTs investigating probiotics and four RCTs investigating synbiotics were included. Overall, 369/647 (57%) responded to probiotic treatment and 252/567 (44%) to control (RR 1.28, 95% CI 1.07, 1.52, p = 0.007). Probiotics increased stool frequency (SMD 0.71, 95% CI 0.37, 1.04, p < 0.00001), with Bifidobacterium lactis having a significant effect, but not mixtures of probiotics, Bacillus coagulans Unique IS2 or Lactobacillus casei Shirota. Probiotics did not impact stool consistency (SMD 0.26, 95% CI -0.03, 0.54, p = 0.08). Probiotics improved integrative symptom scores compared to control (SMD -0.46, 95% CI -0.89, -0.04). Synbiotics did not impact stool output or integrative symptom scores compared to control.

CONCLUSIONS

Certain probiotics may improve response to treatment, stool frequency and integrative constipation symptoms, providing cautious optimism for their use as a dietary management option. There is currently insufficient evidence to recommend synbiotics in the management of chronic constipation. Caution is needed when interpreting these results due to high heterogeneity and risk of bias amongst the studies.

The effect of probiotics on functional constipation in adults: A randomized, double-blind controlled trial

BACKGROUND

Two formulations were developed in the form of an oral sachet containing probiotics, and their efficacy and safety were evaluated in adults with functional constipation.

METHODS

One formulation with Lactobacillus acidophilus, Bifidobacterium bifidum and Lactobacillus rhamnosus (3 billion Colony Forming Units - CFU); and another with Lactobacillus acidophilus, Bifidobacterium bifidum, Lactobacillus rhamnosus, Lactobacillus paracasei, Bifidobacterium longum, Bifidobacterium lactis, Lactobacillus casei, Bifidobacterium animallis (8 billion CFU). The participants were randomized in a 3-arm parallel study and one oral sachet was auto-administered once a day for 30 days.

RESULTS

Primary outcomes were improvement in increasing the frequency of weekly bowel movements and improvement in stool quality. Secondary outcomes were number of adverse events. In the first week one observed an increase in stool frequency and in the quality of stools, showing an improvement in constipation. No statistically significant differences were observed between the three treatment groups in relation to these outcomes (P ≥ .05). Only one adverse event was observed in a patient of group 2, related to abdominal pain.

CONCLUSION

The two probiotic cocktails were effective in improving the symptoms of functional constipation, by increasing both the weekly frequency of evacuation and stool quality, and were deemed safe. Clinicaltrials.gov number: NCT04437147.

A Predictive Growth Model for Pro-technological and Probiotic Lacticaseibacillus paracasei Strains Fermenting White Cabbage

Bacterial strains belonging to Lacticaseibacillus paracasei species are generally used as starters in food fermentations and/or as probiotics. In the current study, the growth cardinal parameters of four L. paracasei strains (IMPC2.1, IMPC4.1, P40 and P101), isolated from table olives or human source, were determined. Strains were grown in liquid medium and incubated at several temperatures (10 values from 5.5°C–40°C) and pH (15 values from 3.2 to 9.1) along the growth range. The cardinal temperature model was used to describe temperature effects on the maximum specific growth rate of L. paracasei whereas new equations were developed for the effect of pH. The estimated T_min values ranged between −0.97°C and 1.95°C and were lower than 0°C for strains IMPC4.1 and P101. Strain P40 was able to grow in the most restricted range of temperature (from 1.95°C to 37.46°C), while strain IMPC4.1 was estimated to survive at extreme conditions showing the lowest pH_min. Maximum specific growth rates of L. paracasei IMPC2.1 in white cabbage (Brassica oleracea var. capitata) were used to calculate the correction factor (C_f) defined as the bias between the bacterial maximum specific growth rate in broth and in the food matrix. A simple bi-linear model was also developed for the effect of temperature on the maximum population density reached in white cabbage. This information was further used to simulate the growth of L. paracasei strains in cabbage and predict the time to reach the targeted probiotic level (7 log₁₀ CFU/g) using in silico simulations. This study demonstrates the potential of the predictive microbiology to predict the growth of beneficial and pro-technological strains in foods in order to optimize the fermentative process.

Effects of Lactobacillus plantarum P9 Probiotics on Defecation and Quality of Life of Individuals with Chronic Constipation: Protocol for a Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Background

Although probiotics have been shown to improve constipation-related symptoms, a clear consensus on the use of probiotics as a constipation-relieving agent has not been reached, which is attributed to the limited available evidence and inconsistent protocols used in existing studies.

Method

A randomized, double-blind, placebo-controlled clinical trial is designed to study the efficiency and possible mechanism of action of probiotics for chronic constipation, in which 200 eligible volunteers with chronic constipation will be randomly assigned to a probiotic group (oral Lactobacillus plantarum P9 probiotic powder, 100 billion colony-forming units (CFUs)/day) or a placebo group. Volunteers, treatment distributors, data collectors, and data analysts will be blinded. The primary outcome is the weekly mean frequency of complete spontaneous bowel movements (CSBMs), and secondary outcomes include weekly mean frequency of CSBMs ≥3, weekly mean frequency of spontaneous bowel movements (SBMs), weekly mean stool appearance score, weekly mean difficulty of passing stool score, weekly percentage of volunteers who use auxiliary measures to assist with defecation (WPUAMA), quality-of-life (QOL) score, emotional status score, gut microbiome, and faecal metabolome. Each outcome measure will be assessed at the time points of preadministration (day 0), administration (day 14 and/or 28), and postadministration (day 42) to identify inter- and intragroup differences. Adverse events will be recorded to evaluate the safety of L. plantarum P9. Discussion. The protocol will provide methodological guidance for other similar studies, avoiding methodological bias and ultimately facilitating the formulation of consensus on the use of probiotics as a constipation-relieving agent. In addition, the results are more comprehensive than those of existing studies and may objectively and scientifically reflect the effectiveness of L. plantarum P9 on constipation. If the expected study findings are obtained, L. plantarum P9, taken as a probiotic, may become a complementary choice for chronically constipated patients. This trial is registered with Chinese Clinical Trial Registry (ChiCTR) (no. ChiCTR2000038396) registered on November 22, 2020, https://www.chictr.org.cn/showproj.aspx?proj=54024.

Bifidobacterium longum relieves constipation by regulating the intestinal barrier of mice

Constipation is a major health concern worldwide, requiring effective and safe treatment options. This study mainly focused on three species and nine strains of bifidobacteria from different sources to study their abilities to relieve constipation induced by loperamide in BALB/C mice. By monitoring constipation-related indicators, it was found that only Bifidobacterium longum (B. longum) relieved constipation, which indicated that bifidobacteria had inter-species differences in relieving constipation. Furthermore, through the detection of biological, chemical, mechanical, and immune barriers in mice, it was discovered that B. longum upregulates the relative abundance of 22 genera that were positively related to faecal water content, small intestinal propulsion rate, acetate, propionate, and intestinal mechanical barrier and negatively correlated with inflammatory factors, AQP8 and the time of first black stool and downregulates the relative abundance of Akkermansia. Furthermore, it increased the level of acetate in faeces and reduced the expression of AQP8 in the colon. This enhances intestinal motility and improves water and electrolyte metabolism. Meanwhile, it inhibited inflammation and prevented loperamide-induced intestinal barrier damage in constipated mice by upregulating occludin and downregulating IL-1β and TNF-α. In summary, B. longum relieved constipation by regulating the intestinal barrier in constipated mice.

Probiotics and Phytochemicals: Role on Gut Microbiota and Efficacy on Irritable Bowel Syndrome, Functional Dyspepsia, and Functional Constipation

Functional gastrointestinal disorders (FGIDs), such as irritable bowel syndrome, functional constipation, and functional dyspepsia, have had a high prevalence over the past few years. Recent evidence suggests that functional foods and bioactive compounds, such as probiotics and phytochemicals, may have a positive effect in treating the symptoms of the above diseases. In this systematic review study, 32 published studies were selected with the use of comprehensive scientific databases, according to PRISMA guidelines, with emphasis on recent interventional studies that reflect the effect of probiotics and selected phytochemicals on the improvement of FGID symptoms. The bioactive compounds in the selected studies were administered to patients either in capsule form or in enriched food products (yogurt, juice, etc.). According to the results, there is a correlation between the consumption of probiotics and phytochemicals, such as polyphenols, and the relief of symptoms in selected gastrointestinal disorders. Enriching foods that are regularly consumed by the population, such as fruit juices, yogurt, and cheese, with ingredients that may have a positive effect on gastrointestinal disorders, could be a possible novel goal for the management of these diseases. However, further evidence is required for the role of probiotics and phytochemicals in FGIDs to be fully understood.

The effect of probiotics on functional constipation in adults: Double-blind, randomized, placebo-controlled study

BACKGROUND

: Evacuation disorders are common in industrialized countries, affecting an average of 15% to 20% of the healthy adult population. Probiotic therapy can reduce functional constipation and increase both the number of weekly bowel movements and quality of stools. Based on the hypothesis that a combination of more strains may provide better results for constipation and facilitate adherence to treatment, this study will evaluate the efficacy and safety of a combination of different strains of Lactobacillus sp. and Bifidobacterium sp. in functional constipation.

METHODS

: A single-centre trial of adults aged 20 to 80 years with intestinal constipation will be conducted at a Gastroenterology Clinic in Sorocaba, State of São Paulo, Brazil. Participants will be allocated into 3 groups receiving: 1. mixture of 3 probiotics: [Lactobacillus acidophilus, Bifidobacterium bifidum, and Lactobacillus rhamnosus (3 × 10⁹ CFU)]; 2. mixture of 8 probiotics [Lactobacillus acidophilus, Bifidobacterium bifidum, Lactobacillus rhamnosus, Lactobacillus paracasei, Bifidobacterium longum, Bifidobacterium lactis, Lactobacillus defensis, Bifidobacterium animallis (8 × 10⁹ CFU)]; or 3. placebo, for 4 weeks. The outcomes of interest will be change in frequency of weekly bowel movements, change in stool quality according to the 4–6 Bristol scale, number of volunteer withdrawal, number of adverse events and number of serious adverse effect.

DISCUSSION:

The probiotic products are expected to induce beneficial changes in the intestinal microbiota, thereby increasing intestinal frequency to over 3 times a week and improving stool quality. The results can guide patients and healthcare practitioners and help in decision-making in the treatment of functional constipation.

TRIAL REGISTRATION AND REGISTRY NAME:

ClinicalTrials.gov Identifier: NCT04437147: The Effect of Probiotics on Functional Constipation in Adults: Study protocol for Double blind, Randomized, Placebo controlled Study

PROTOCOL VERSION:

Version 01 August 30, 2020.

A multiple-strain probiotic product provides a better enzymatic antioxidant response in individuals with constipation in a double-blind randomized controlled trial

OBJECTIVES

Probiotics may have beneficial effects on intestinal dysbiosis. However, the effects of probiotics on redox and inflammatory responses in intestinal constipation remain unknown. The aim of this study was to investigate the effect of a multiple-strain probiotic on the redox and inflammatory responses in individuals with intestinal constipation.

METHODS

A randomized, double-blind, placebo controlled clinical trial was conducted with individuals diagnosed with constipation (defined according to the Rome IV criteria). The participants were randomized into two groups to receive either a probiotic capsule (PC; n = 25) containing probiotic strains or to receive a control capsule (CC; n = 20) containing a matching placebo for 30 d. In the baseline and at the end of the study, biomarkers of the redox (malondialdehyde, carbonylated protein, antioxidant enzymes, and ferric-reducing antioxidant power) and inflammatory responses, and Rome IV criteria for constipation were analyzed.

RESULTS

The consumption of a multiple-strain probiotic attenuated the reduction of glutathione peroxidase (PC = -9.41 and CC = -19.60; P = 0.041) and glutathione-s-transferase activity (PC = -3.28 and CC = -12.08, P < 0.0001) in erythrocytes and marginally improved the symptom of feeling incomplete defecation in ≥25% of bowel movements, compared with the placebo group. No changes were observed in total antioxidant capacity, oxidative damage, and levels of inflammatory markers in the serum.

CONCLUSIONS

Our data suggested that a multiple-strain probiotic may provide a better enzymatic antioxidant response and partially alleviate the feeling of incomplete defecation in ≥25% of bowel movements in individuals with intestinal constipation.

Probiotics: A Dietary Factor to Modulate the Gut Microbiome, Host Immune System, and Gut-Brain Interaction

Various benefits of probiotics to the host have been shown in numerous human clinical trials. These organisms have been proposed to act by improving the balance of the gut microbiota and enhancing the production of short-chain fatty acids, as well as by interacting with host cells in the gastrointestinal tract, including immune cells, nerve cells, and endocrine cells. Although the stimulation of host cells by probiotics and subsequent signaling have been explained by in vitro experiments and animal studies, there has been some skepticism as to whether probiotics can actually interact with host cells in the human gastrointestinal tract, where miscellaneous indigenous bacteria coexist. Most recently, it has been shown that the ileal microbiota in humans after consumption of a fermented milk is occupied by probiotics for several hours, indicating that there is adequate opportunity for the ingested strain to stimulate the host cells continuously over a period of time. As the dynamics of ingested probiotics in the human gastrointestinal tract become clearer, further progress in this research area is expected to elucidate their behavior within the tract, as well as the mechanism of their physiological effects on the host.

Effect of Durio zibethinus rind polysaccharide on functional constipation and intestinal microbiota in rats

The prevalence of constipation increases rapidly with the increased pressure of some people's life, which seriously affects the quality of life in related patients. In this study, the improvement of functional constipation by Durio zibethinus Murr rind polysaccharide (DZMP) and the effects of DZMP on intestinal microbiota were investigated in a constipation model of Sprague-Dawley (SD) rats established by loperamide hydrochloride. Results showed that DZMP at 200 mg/kg could significantly (P < 0.05) increase the intestinal transit rate, motilin, gastrin, substance P levels and concentration of short-chain fatty acids (SCFAs), reduce the somatostatin levels and improve the gastrointestinal peristalsis of rats. Sequencing showed that the Lachnospiraceae-NK4A136-group in the rats given 200 mg/kg DZMP (16.07%) was significantly higher than that of the model group (10.13%), while the Desulfovibrio was lower (2.99%) than that of the model group (4.19%). Principal co-ordinates analysis (PcoA) revealed a significant difference in intestinal microbiota composition between the model group and the high-dose DZMP group (200 mg/kg). The results demonstrated that DZMP has a regulatory effect of treating functional constipation and regulating intestinal flora in rats.

Probiotics and constipation: mechanisms of action, evidence for effectiveness and utilisation by patients and healthcare professionals

The aim of this narrative review is to assess and present evidence on the mechanisms of action of probiotics in constipation, their effectiveness and their utilisation by patients and healthcare professionals. Chronic constipation is a common bothersome disorder that has a considerable impact on patients' quality of life. Probiotics have been increasingly investigated for their effectiveness in various disorders, including chronic constipation. Probiotics may affect gut motility and constipation through their impact on the gut microbiota and fermentation, the central and enteric nervous system and the immune system. However, evidence for the effectiveness of probiotics in the management of constipation remains varied, with some strains demonstrating improvements, while others show no effect. Despite the uncertainty in evidence and the fact that the majority of healthcare professionals do not recommend probiotics for constipation, an increased prevalence of probiotic use by people with constipation has been shown. Therefore, there is a need for public health strategies to inform the public about where strong evidence of probiotic effectiveness exist, and where evidence is still weak. Education of healthcare professionals on the increased utilisation of probiotics for constipation by the public and on current evidence for the effectiveness of specific strains is also required.

Isolation and characterization of high exopolysaccharide-producing Weissella confusa VP30 from young children's feces

Background

Lactic acid bacteria (LAB) are known to have a significant ability to colonize the human intestinal tract and adhere to the surface of intestinal epithelial cells. Among the various lactic acid bacteria, exopolysaccharide (EPS) producing strains are known to provide a variety of health benefits for their hosts (e.g. anti-inflammatory, antioxidant, antitumor and stress tolerant effects). Recently, EPSs and EPS-producing lactic acid cultures have gained interest within the food industry and are playing important roles as biothickeners and texturizing agents due to their hydrocolloidal nature. In this study, 156 lactic acid bacterial strains isolated from fecal samples of healthy young children were screened and evaluated for active EPS-production capability.

Results

Among the various human origin lactic acid flora isolated, Weissella confusa VP30 showed the highest EPS productivity and its EPS producing properties were characterized under various cultural conditions in this research. To document the safety of W. confusa VP30, antibiotic resistance, hemolytic, and ammonia production properties were evaluated in addition. No significant negative results were observed. The maximum EPS production by W. confusa VP30 was 59.99 ± 0.91 g/l after 48 h of cultivation in media containing 10% sucrose, far exceeding EPS production by other bacterial strains reported elsewhere. Based on gel permeation chromatography (GPC), the molecular weight of EPS produced by W. confusa VP30 was 3.8 × 10⁶ Da. Structural analysis of the released EPS fraction by ¹³C and ¹H nuclear magnetic resonance (NMR) spectroscopy revealed that W. confusa VP30 can produce dextran with glucose units linked with 96.5% α (1 → 6) glycosidic bonds and 3.5% α (1 → 3) branches.

Conclusion

The high EPS production capability and safety of W. confusa VP30 justify food industry consideration of this cell strain for further evaluation and potential industrial use.

Gut Microbiota and Chronic Constipation: A Review and Update

Background: Chronic constipation, including functional constipation and constipation-type irritable bowel syndrome, is a prevalent, multifactorial gastrointestinal disorder, and its etiology and pathophysiology remain poorly understood. Recently studies using 16S rRNA-based microbiota profiling have demonstrated dysbiosis of gut microbiota in chronic constipation.

Aims: To provide an overview of recent studies for microbiota in chronic constipation and treatments for chronic constipation using probiotics, prebiotics, synbiotics, antibiotics and fecal microbiota transplantation (FMT).

Methods: PubMed searches were performed up to 1 August 2018 using keywords: “IBS,” “IBS-C,” “irritable bowel syndrome,” “irritable bowel syndrome with constipation,” “functional constipation,” “chronic constipation” in combination with “gut microbiota,” “dysbiosis,” “gut microflora” for microbiota in chronic constipation, and in combination with “probiotics,” “prebiotics,” “synbiotics,” “antibiotics,” and “fecal microbiota transplantation.”

Results: The findings of gut microbiota in functional constipation are inconsistent, and currently no consensus exists. Although no clear consensus exists, compared with healthy subjects, IBS-C patients have a lower level of Actinobacteria, including Bifidobacteria, in their fecal samples and a higher level of Bacteroidetes in their mucosa. In most randomized controlled and parallel-group trials, probiotics, prebiotics, synbiotics, antibiotics, and FMT therapy for chronic constipation were effective with few side effects. However, there are many studies in a small number and the types of probiotics are different, it is difficult to evaluate the effect.

Conclusions: Evidence indicates that dysbiosis of gut microbiota may contribute to functional constipation and constipation-type irritable bowel syndrome. Targeting treatments for the dysbiosis of constipation by probiotics, prebiotics, synbiotics, antibiotics, and FMT may be a new option, especially for refractory constipation to conventional therapies.

Quality of ready-to-eat swordfish fillets inoculated with Lactobacillus paracasei IMPC 2.1

BACKGROUND

The quality of marinated ready-to-eat (RTE) swordfish fillets, with or without inoculation with the probiotic strain Lactobacillus paracasei IMPC 2.1, was assessed over 3 months of refrigerated storage at 4 °C. RTE probiotic and control fish fillets were sampled after 7, 14, 30, 60, and 90 days of storage. Microbiological tests were performed, and fatty acid (FA) profiles and malondialdehyde content were examined. Microbiological counts, including total viable count, lactic acid bacteria (LAB), yeasts, moulds, Enterobacteriaceae, and Pseudomonadaceae were determined.

RESULTS

Inoculation successfully ensured the growth of the probiotic strain and prevented the growth of other LAB. The two RTE products showed significant differences in lipid profile and lipid oxidation during storage. In particular, inoculation with L. paracasei IMPC 2.1 increased the amount of polyunsaturated FAs and limited the amount of monounsaturated FAs and oleic acid, as well as lipid oxidation. It thus represents an interesting strategy for preserving the chemical quality of fish fillets and an alternative means of delivering probiotics.

CONCLUSION

Probiotic inoculation with Lactobacillus paracasei seemed to delay lipid oxidation of the fish flesh and increase the retention of polyunsaturated FAs, suggesting a potential application for this strain in the seafood industry. © 2018 Society of Chemical Industry.

Mechanisms of Action of Probiotics

Probiotics are living microorganisms that confer health benefits to the host when administered in adequate amounts; however, dead bacteria and their components can also exhibit probiotic properties. Bifidobacterium and strains of lactic acid bacteria are the most widely used bacteria that exhibit probiotic properties and are included in many functional foods and dietary supplements. Probiotics have been shown to prevent and ameliorate the course of digestive disorders such as acute, nosocomial, and antibiotic-associated diarrhea; allergic disorders such as atopic dermatitis (eczema) and allergic rhinitis in infants; and Clostridium difficile-associated diarrhea and some inflammatory bowel disorders in adults. In addition, probiotics may be of interest as coadjuvants in the treatment of metabolic disorders, including obesity, metabolic syndrome, nonalcoholic fatty liver disease, and type 2 diabetes. However, the mechanisms of action of probiotics, which are diverse, heterogeneous, and strain specific, have received little attention. Thus, the aim of the present work was to review the main mechanisms of action of probiotics, including colonization and normalization of perturbed intestinal microbial communities in children and adults; competitive exclusion of pathogens and bacteriocin production; modulation of fecal enzymatic activities associated with the metabolization of biliary salts and inactivation of carcinogens and other xenobiotics; production of short-chain and branched-chain fatty acids, which, in turn, have wide effects not only in the intestine but also in peripheral tissues via interactions with short-chain fatty acid receptors, modulating mainly tissue insulin sensitivity; cell adhesion and mucin production; modulation of the immune system, which results mainly in the differentiation of T-regulatory cells and upregulation of anti-inflammatory cytokines and growth factors, i.e., interleukin-10 and transforming growth factor; and interaction with the brain-gut axis by regulation of endocrine and neurologic functions. Further research to elucidate the precise molecular mechanisms of action of probiotics is warranted.

Nonpharmacological conservative treatments for chronic functional constipation: A systematic review and network meta-analysis

BACKGROUND

Patients with functional chronic constipation (CFC) often select nonpharmacological treatments. We aimed to examine the comparative effectiveness of nonpharmacological conservative treatments in treating CFC.

METHODS

We searched MEDLINE, EMBASE, Cochrane library, CINAHL, AMED, ISI web of knowledge, and conference proceedings from January 2000 to June 2016. Randomized controlled trials comparing nonpharmacological conservative treatments with placebo, sham interventions, or conventional treatments were included. Nonpharmacological conservative treatments were defined as interventions without involvement of medication or surgery. We extracted trial data in duplicate and assessed the risk of bias. We pooled continuous data using standard mean differences (SMDs) and binary data using risk ratios (RRs), and we provided their 95% confidence intervals.

KEY RESULTS

We included 33 trials (4324 participants and 8 nonpharmacological treatments). Compared with placebo interventions, TENS (SMD 1.60, 95% CI 0.28-2.92), probiotic (SMD 1.40, 95% CI 0.94-1.86), and acupuncture (SMD 1.00, 95% CI 0.39-1.60) had significantly larger effect on stool frequency; acupuncture (RR 1.56, 95% CI 1.14-2.14) had significantly higher responder rate; and moxibustion (SMD 2.50, 95% CI 0.05-4.95) had significant larger effect on Bristol score. Compared with laxative, acupuncture had significantly larger effect on stool frequency (RR 2.01, 95% CI 1.16-3.49) and had lower rate of adverse events (RR 0.38, 95% CI 0.18-0.80).

CONCLUSIONS

TENS and acupuncture relatively ranked the best in managing CFC, but the results should be interpreted with caution due to small study effects. Registration number: PROSPERO CRD42014006686.

Microbial treatment in chronic constipation

Chronic functional constipation is a kind of common intestinal disease that occurs in children, adults and elderly people. This disease not only causes great influence to physiological function, but also results in varying degrees of psychological barriers. At present, constipation treatments continue to rely on traditional methods such as purgative therapy and surgery. However, these approaches can disrupt intestinal function. Recent research between intestinal diseases and gut microbiota has gradually revealed a connection between constipation and intestinal flora disturbance, providing a theoretical basis for microbial treatment in chronic constipation. Microbial treatment mainly includes probiotic preparations such as probiotics, prebiotics, synbiotics and fecal microbiota transplantation (FMT). Due to its safety, convenience and curative effect, probiotic preparations have been widely accepted, especially gradually developed FMT with higher curative effects. Microbial treatment improves clinical symptoms, promotes the recovery of intestinal flora, and has no complications during the treatment process. Compared with traditional treatments, microbial treatment in chronic constipation has advantages, and is worthy of further promotion from clinical research to clinical application.

Probiotic Incorporation in Edible Films and Coatings: Bioactive Solution for Functional Foods

Nowadays, the consumption of food products containing probiotics, has increased worldwide due to concerns regarding healthy diet and wellbeing. This trend has received a lot of attention from the food industries, aiming to produce novel probiotic foods, and from researchers, to improve the existing methodologies for probiotic delivery or to develop and investigate new possible applications. In this sense, edible films and coatings are being studied as probiotic carriers with many applications. There is a wide variety of materials with film-forming ability, possessing different characteristics and subsequently affecting the final product. This manuscript aims to provide significant information regarding probiotics and active/bioactive packaging, to review applications of probiotic edible films and coatings, and to discuss certain limitations of their use as well as the current legislation and future trends.

Mechanisms of Action of Probiotics and the Gastrointestinal Microbiota on Gut Motility and Constipation

Constipation is a common and burdensome gastrointestinal disorder that may result from altered gastrointestinal motility. The effect of probiotics on constipation has been increasingly investigated in both animal and human studies, showing promising results. However, there is still uncertainty regarding the mechanisms of action of probiotics on gut motility and constipation. Several factors are vital to normal gut motility, including immune and nervous system function, bile acid metabolism and mucus secretion, and the gastrointestinal microbiota and fermentation; an imbalance or dysfunction in any of these components may contribute to aberrant gut motility and, consequently, symptoms of constipation. For example, adults with functional constipation have significantly decreased numbers of bifidobacteria (with one study showing a mean difference of 1 log₁₀/g) and lactobacilli (mean difference, 1.4 log₁₀/g) in stool samples, as well as higher breath methane, compared with control subjects. Modifying the gut luminal environment with certain probiotic strains may affect motility and secretion in the gut and, hence, provide a benefit for patients with constipation. Therefore, this review explores the mechanisms through which probiotics may exert an effect on gut motility and constipation. Nevertheless, the majority of current evidence is derived from animal studies, and therefore, further human studies are needed to determine the mechanisms through specific probiotic strains that might be effective in constipation.

Analysis of short-chain fatty acids in human feces: A scoping review

Short-chain fatty acids (SCFAs) play a crucial role in maintaining homeostasis in humans, therefore the importance of a good and reliable SCFAs analytical detection has raised a lot in the past few years. The aim of this scoping review is to show the trends in the development of different methods of SCFAs analysis in feces, based on the literature published in the last eleven years in all major indexing databases. The search criteria included analytical quantification techniques of SCFAs in different human clinical and in vivo studies. SCFAs analysis is still predominantly performed using gas chromatography (GC), followed by high performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR) and capillary electrophoresis (CE). Performances, drawbacks and advantages of these methods are discussed, especially in the light of choosing a proper pretreatment, as feces is a complex biological material. Further optimization to develop a simple, cost effective and robust method for routine use is needed.

Bifidobacterium adolescentis Exerts Strain-Specific Effects on Constipation Induced by Loperamide in BALB/c Mice

Constipation is one of the most common gastrointestinal complaints worldwide. This study was performed to determine whether Bifidobacterium adolescentis exerts inter-strain differences in alleviating constipation induced by loperamide in BALB/c mice and to analyze the main reasons for these differences. BALB/c mice underwent gavage with B. adolescentis (CCFM 626, 667, and 669) once per day for 17 days. The primary outcome measures included related constipation indicators, and the secondary outcome measures were the basic biological characteristics of the strains, the concentration changes of short-chain fatty acids in feces, and the changes in the fecal flora. B. adolescentis CCFM 669 and 667 relieved constipation symptoms by adhering to intestinal epithelial cells, growing quickly in vitro and increasing the concentrations of propionic and butyric acids. The effect of B. adolescentis on the gut microbiota in mice with constipation was investigated via 16S rRNA metagenomic analysis. The results revealed that the relative abundance of Lactobacillus increased and the amount of Clostridium decreased in the B. adolescentis CCFM 669 and 667 treatment groups. In conclusion, B. adolescentis exhibits strain-specific effects in the alleviation of constipation, mostly due to the strains’ growth rates, adhesive capacity and effects on the gut microbiome and microenvironment.

Therapeutic Modulation of Gut Microbiota in Functional Bowel Disorders

Functional bowel disorders (FBDs) are functional gastrointestinal disorders with symptoms attributable to the middle or lower gastrointestinal tract. These include irritable bowel syndrome, functional bloating, functional constipation, functional diarrhea, and unspecified FBD. Increasing evidence has emerged of late that intestinal microbiota is involved in the pathogenesis of FBDs. In this review, the therapeutic benefits and future perspectives of the currently available strategies for modifying the gut microbiota in FBDs are described, focusing primarily on irritable bowel syndrome and functional constipation.

TRANSLATION AND VALIDATION OF THE BRAZILIAN PORTUGUESE VERSION OF THE GASTROINTESTINAL SYMPTOM RATING SCALE (GSRS) QUESTIONNAIRE

BACKGROUND

- Bowel function is a widely evaluated parameter in interventional and longitudinal studies since it is associated with good maintenance of health. The evaluation of intestinal function has been performed by many questionnaires, however, there are few options validated in Brazilian Portuguese.

OBJECTIVE

- The aim of this work was to translate and validate into Brazilian Portuguese the Gastrointestinal Symptom Rating Scale (GSRS) questionnaire.

METHODS

- Translation and cultural adaptation were performed according to a previously established methodology followed by reliability calculations.

RESULTS

- The final translated GSRS questionnaire showed an adequate value of overall reliability of Cronbach's alpha of 0.83, and its domains were classified from acceptable to adequate. The overall test-retest reliability by intraclass correlation coefficient (ICC) was 0.84, considered excellent.

CONCLUSION

- The GSRS was translated and validated into Brazilian Portuguese, with appropriate internal consistency and reliability and is available to be used in assessments of bowel function.

Normative values for stool frequency and form using Rome III diagnostic criteria for functional constipation in adults: systematic review with meta-analysis

When designing clinical trials focused on functional constipation therapies, understanding the normative values of populations selected using the Rome III criteria is important for estimating baseline symptom severity, and for power analysis and sample size calculations. The objective of this review was to determine normative ranges for stool frequency and form in adults with functional constipation (Rome III criteria). Eligible studies reported stool frequency or form; random effects meta-analysis was performed with subgroup analyses to explore sources of heterogeneity. A total of 25 studies (43 groups, 2292 subjects) were included. Pooled estimates were 2.7 (95% CI 2.4-3.0) for weekly stools and 2.4 (95% CI 2.1-2.6) for stool form (Bristol scale). Heterogeneity was high for both outcomes (both I²=96%, P<0.001). Subgroup analysis revealed that weekly bowel movement frequency was higher in larger than in smaller studies (3.1 vs. 2.3, P<0.001) and in studies conducted in Europe compared with those in the Americas (3.1 vs. 2.2, P=0.02). For stool form, the use of a daily diary versus subject recall was the sole explanatory variable (2.5 vs. 2.1, P<0.05). We conclude that adults with functional constipation have significant variation in stool frequency and form, explained in part by geography and study design.

Effect of Lactobacillus paracasei Culture Filtrates and Artichoke Polyphenols on Cytokine Production by Dendritic Cells

The most recent trend in research on probiotic bacteria aims at the exploitation of bioactive bacterial compounds that are responsible for health-promoting effects and suitable for medical applications. Therefore, the main purpose of this study was to ascertain if the immunomodulatory effects of L. paracasei strains on dendritic cells (DCs) were caused by bacterial metabolites released in the culture medium. For that reason, bacterial strains were grown in two media generally used for the culture of DCs, and the effects of culture filtrates on the maturation of DCs and cytokine production were evaluated. Moreover, to reveal potential synergistic effects on the immunomodulation of DCs, an artichoke phenolic extract (APE) was added to the media before bacterial growth. The experiments pointed out an interesting anti-inflammatory activity of a culture filtrate obtained after growing a probiotic L. paracasei strain in one of the media supplemented with APE. Therefore, this culture filtrate—which combines the anti-inflammatory activity and the other well-known health-promoting properties of artichoke phenolic compounds—could represent the basis for future particular exploitations.

Intestinal microbiota and chronic constipation

Chronic constipation is a prevalent, burdensome gastrointestinal disorder whose aetiology and pathophysiology remains poorly understood and is most likely multifactorial. Differences in the composition of the intestinal microbiota have been demonstrated when constipated patients and healthy controls have been compared. Growing evidence indicates that alterations of intestinal microbiota may contribute to constipation and constipation-related symptoms. The intestinal microbiota is a collection of microorganisms that live within the gastrointestinal tract, and perform many important health-promoting functions. The intestinal microbiota aids in the breakdown of food products into absorbable nutrients, stimulates the host immune system, prevents growth of pathogenic bacteria and produces a great variety of biologically important compounds. In this review, we will summarize the current evidence supporting roles of the intestinal microbiota in the pathogenesis and management of chronic constipation. The discussion will shed light on the novel mechanisms of intestinal microbiota and gut function interactions, which is invaluable in ultimately developing new therapeutic tools for the treatment of chronic constipation.

Change of Fecal Flora and Effectiveness of the Short-term VSL#3 Probiotic Treatment in Patients With Functional Constipation

Background/Aims

We investigated gut flora characteristics in patients with functional constipation (FC) and influences of short-term treatment with VSL#3 probiotic on flora and symptom improvement.

Methods

Thirty patients fulfilling Rome III criteria for FC and 30 controls were enrolled. Fecal samples were obtained before and after VSL#3 intake (one sachet twice daily for 2 weeks) and flora were examined by quantitative real-time polymerase chain reaction (qRT-PCR). Symptom changes were also investigated.

Results

The fold differences in Bifidobacterium and Bacteroides species were significantly lower in feces from FC, compared to in controls (P = 0.030 and P = 0.021). After taking VSL#3, the fold differences in Lactobacillus, Bifidobacterium and Bacteroides species increased in controls (P = 0.022, P = 0.018, and P = 0.076), but not in FC. Mean Bristol scores and complete spontaneous bowel movements (CSBMs)/week increased significantly in FC after ingesting VSL#3 (both P < 0.001). Relief of subjective CSBM frequency, stool consistency and abdominal bloating were reported in 70%, 60%, and 47% of patients. After VSL#3 cessation, 44.4% of patients with symptom improvement experienced constipation recurrence mostly within one month.

Conclusions

Bifidobacterium and Bacteroides species might be quantitatively altered in FC. A short-term VSL#3 treatment can improve clinical symptoms of FC. Further studies are needed to investigate VSL#3’s additional effects beyond altering gut flora to allevate constipation.

Clinical study of electro-acupuncture treatment with different intensities for functional constipation patients

Functional constipation (FC) is a common functional bowel disorder disease that affects life quality of a large number of people. This study aimed to explore the impact of different intensities of electro-acupuncture (EA) treatment for FC patients. Totally, 111 patients with FC meeting the Rome III criteria were randomly assigned to different intensities of EA groups (low and high intensity of EA groups) and medicine-controlled (MC) group. In EA groups, patients were treated with EA at quchi (LI11) and shangjuxu (ST37) bilaterally for 4 weeks, 5 times/week in the first 2 weeks, and 3 times/week in the last 2 weeks. In MC group, 5 mg mosapride citrate was administered orally 3 times/day for 4 weeks. Spontaneous bowel movement frequency each day was recorded using a constipation diary. Self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were used to assess the patients' psychological state. Cortisol (CORT), substance P (SP), and vasoactive intestinal polypeptide (VIP) were evaluated at baseline and at the end of 4 weeks after treatment. As compared with the baseline, there was statistically significant increase in stool frequency every week (P<0.01), but there was no statistically significant difference among the three groups. As compared with the baseline, after 4 weeks of EA therapy, the scores of SDS and serum levels of CORT were decreased significantly in low intensity of EA group (P<0.01), and the serum levels of SP and VIP were increased significantly (P<0.05); the scores of SAS and SDS and serum levels of CORT were decreased significantly in high intensity of EA group (P<0.05), and the serum levels of SP and VIP were increased significantly (P<0.05); the serum levels of CORT and VIP were increased significantly in MC group (P<0.05). As compared with MC group, after 4 weeks of treatment, the serum levels of SP were signifcicantly increased in low intensity of EA group (P<0.01). Low and high intensities of EA could increase the stool frequency, improve the FC patient's anxiety and depression, reduce the serum levels of CORT, and increase the serum levels of SP and VIP effectively. It is concluded that both low and high intensities of EA are effective for FC patients, but there is no significant difference between the low and high intensities of EA.

The effect of probiotics on functional constipation in adults: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Functional constipation is a prevalent, burdensome gastrointestinal disorder whose treatment remains challenging. Probiotics have been increasingly investigated in its management.

OBJECTIVE

The aim was to investigate the effect of probiotics on gut transit time, stool output, and constipation symptoms in adults with functional constipation via a systematic review and meta-analysis of randomized controlled trials (RCTs).

DESIGN

Studies were identified by searching 4 electronic databases, back-searching reference lists, contacting authors, and hand-searching abstracts. RCTs that reported administration of probiotics in adults with functional constipation were included. Two reviewers independently performed the screening, data extraction, and bias assessment. Outcome data were synthesized by using weighted mean differences (WMDs) or standardized mean differences (SMDs) with the use of a random-effects model.

RESULTS

A total of 660 records were identified of which 14 were eligible (1182 patients). Overall, probiotics significantly reduced whole gut transit time by 12.4 h (95% CI: -22.3, -2.5 h) and increased stool frequency by 1.3 bowel movements/wk (95% CI: 0.7, 1.9 bowel movements/wk), and this was significant for Bifidobacterium lactis (WMD: 1.5 bowel movements/wk; 95% CI: 0.7, 2.3 bowel movements/wk) but not for Lactobacillus casei Shirota (WMD: -0.2 bowel movements/wk; 95% CI: -0.8, 0.9 bowel movements/wk). Probiotics improved stool consistency (SMD: +0.55; 95% CI: 0.27, 0.82), and this was significant for B. lactis (SMD: +0.46; 95% CI: 0.08, 0.85) but not for L. casei Shirota (SMD: +0.26; 95% CI: -0.30, 0.82). No serious adverse events were reported. Attrition and reporting bias were high, whereas selection bias was unclear due to inadequate reporting.

CONCLUSIONS

Probiotics may improve whole gut transit time, stool frequency, and stool consistency, with subgroup analysis indicating beneficial effects of B. lactis in particular. However, caution is needed with the interpretation of these data due to their high heterogeneity and risk of bias. Adequately powered RCTs are required to better determine the species or strains, doses, and duration of use of probiotics that are most efficacious.

Structural changes in the gut microbiome of constipated patients

Previous studies using culture-based methods suggested an association between constipation and altered abundance of certain taxa of the colonic microbiome. We aim to examine the global changes in gut microbial composition of constipated patients. A cross-sectional pilot study using 16S rRNA gene pyrosequencing was performed to compare stool microbial composition of eight constipated patients and 14 nonconstipated controls. Only obese children were enrolled so that the microbiome features associated with constipation would not be obscured by those associated with obesity. The sequencing reads were processed by QIIME for quantitative analysis of the microbial composition at genus and above levels. Dietary intake for all the individuals was assessed by dietary recalls and a food frequency questionnaire. The ecological diversities of fecal microbiome of the constipated patients differed from those of the controls. Significantly decreased abundance in Prevotella and increased representation in several genera of Firmicutes were observed in constipated patients compared with controls. The conventional probiotic genera Lactobacillus and Bifidobacteria were not decreased in the microbiomes of the constipated patients. These alterations in the fecal microbiome of constipated patients suggested that a novel probiotic treatment including certain Prevotella strains may be more effective than conventional probiotic products incorporating Lactobacillus or Bifidobacterium species. While it is possible that the observed changes in the microbiome in constipated subjects are a consequence of a low-fiber diet, these changes also predict a different pattern of bacterial fermentation end-products, such as increased butyrate production, which may contribute to pathogenesis of constipation.

Emerging role of probiotics and antimicrobials in the management of irritable bowel syndrome

OBJECTIVE

To review the potential role of probiotics and antimicrobials for management of functional bowel disorders (FBDs), with a focus on irritable bowel syndrome (IBS).

RESEARCH DESIGN AND METHODS

Relevant adult data were identified via PubMed, with additional references obtained by reviewing bibliographies from selected articles.

RESULTS

Probiotic treatment involves colonizing the intestines with beneficial microorganisms, whereas antimicrobial therapy involves modulation of the bacterial load and/or host response. A meta-analysis reported that all probiotic species evaluated improved flatulence compared with placebo; some, but not all, species improved abdominal pain and abdominal bloating/distension; and no species evaluated improved stool frequency or consistency, straining during stool evacuation, sense of incomplete evacuation, or fecal urgency. Two additional meta-analyses reported that probiotics significantly improved overall IBS symptoms. Individual studies have demonstrated potential benefits of probiotics for functional constipation symptoms. The nonsystemic antimicrobials neomycin and rifaximin have been evaluated in patients with IBS and other FBDs. Neomycin may improve global IBS symptoms and provide bowel normalization versus placebo, but the risk of ototoxicity and the development of clinically relevant bacterial resistance may limit its use for recurrent symptoms. In phase 3 randomized studies, rifaximin-treated patients were significantly more likely than placebo-treated patients to achieve adequate relief of global IBS symptoms and abdominal bloating. Although preliminary data suggest that development of clinically relevant bacterial resistance is unlikely with rifaximin, prospective data are needed, and a phase 3 study is ongoing. Limitations of evidence for probiotics include small populations analyzed and lack of clarity in optimal dosing regimen; antimicrobial evidence would benefit from better understanding of the effects of repeated treatment in patients with IBS.

CONCLUSIONS

Probiotics and nonsystemic antibiotics have a place in IBS management. Additional studies are needed to establish optimal regimens and identify subgroups of patients most likely to benefit from these therapies.

Nutrigenetics, nutrigenomics and inflammatory bowel diseases

Inflammatory bowel disease includes ulcerative colitis and Crohn's disease, which are both inflammatory disorders of the gastrointestinal tract. Both types of inflammatory bowel disease have a complex etiology, resulting from a genetically determined susceptibility interacting with environmental factors, including the diet and gut microbiota. Genome Wide Association Studies have implicated more than 160 single-nucleotide polymorphisms in disease susceptibility. Consideration of the different pathways suggested to be involved implies that specific dietary interventions are likely to be appropriate, dependent upon the nature of the genes involved. Epigenetics and the gut microbiota are also responsive to dietary interventions. Nutrigenetics may lead to personalized nutrition for disease prevention and treatment, while nutrigenomics may help to understand the nature of the disease and individual response to nutrients.

Pathobiology and potential therapeutic value of intestinal short-chain fatty acids in gut inflammation and obesity

BACKGROUND

The lumen of the gastrointestinal tract contains many substances produced from the breakdown of foodstuffs, from salivary, esophageal, intestinal, hepatic, and pancreatic secretions, and from sloughed cells present in the gastrointestinal lumen. Although these substances were traditionally regarded as waste products, there is increasing realization that many can be biologically active, either as signalling compounds or as nutrients. For example, proteins are broken down into amino acids, which are then sensed by nutrient receptors. The gut microbiome, which is at highest abundance in the ileocecum, has powerful metabolic activity, digesting and breaking down unabsorbed carbohydrates, proteins, and other ingested nutrients into phenols, amines, volatile organic compounds, methane, carbon dioxide, hydrogen, and hydrogen sulfide into volatile fatty acids, also called short-chain fatty acids (SCFAs).

CONCLUSION

These latter substances are the topic of this review. In this review, we will briefly discuss recent advances in the understanding SCFA production, signalling, and absorption, followed by a detailed description and discussion of trials of SCFAs, probiotics, and prebiotics in the treatment of gastrointestinal disease, in particular ulcerative colitis (UC), pouchitis, short bowel syndrome, and obesity.

Probiotics in luminal gastroenterology: the current state of play

In recent years, there has been a growing interest in the use of probiotics in various areas of gastrointestinal (GI) health. Probiotics are defined as live microorganisms that provide beneficial health effects on the host when administered in adequate amounts. Various probiotics have been shown to suppress bacterial growth, modulate the immune system and improve intestinal barrier function. However, despite several studies with promising results, most trials are small and many have substantial methodological limitations. However, with better targeting and appropriate randomised controlled trials, this area may soon yield important therapeutic strategies to optimise GI health. Here, we review the current knowledge of probiotics of relevance to luminal GI health.