Food supplements and diet as treatment options in irritable bowel syndrome

Relationship between Markers of Gut Barrier Function and Erythrocyte Membrane PUFAs in Diarrhea-Predominant IBS Patients Undergoing a Low-FODMAP Diet

Many patients with irritable bowel syndrome (IBS) have a compromised intestinal barrier associated with low-grade inflammation. Polyunsaturated fatty acids (PUFAs) are potential mediators of inflammation: omega-6 PUFAs are pro-inflammatory, while omega-3 PUFAs are antioxidant and anti-inflammatory. Zonulin is a potential biomarker for small intestinal permeability (s-IP). This study investigated the relationship between PUFAs and gastrointestinal (GI) barrier integrity in IBS patients with predominant diarrhea (IBS-D). We evaluated GI barrier function indicators in the urine and bloodstream and erythrocyte membrane PUFA composition in 38 IBS-D patients (5 men, 33 women, 44.11 ± 1.64 years), categorized at baseline by fecal zonulin levels into high (≥107 ng/mL, H-FZ) and normal (<107 ng/mL N-FZ) groups. Evaluations were conducted prior to and following a 12-week diet low in FODMAPs (LFD). At baseline, H-FZ patients had s-IP significantly higher than the reference value, lower n-3 PUFAs levels, and higher n-6/n-3 PUFAs and arachidonic acid (AA) to eicosapentaenoic acid (EPA) ratios than N-FZ. After LFD, H-FZ patients showed significant increases in n-3 PUFAs levels; decreases in n-6 PUFAs, n-6/n-3 PUFAs and AA/EPA ratios; and improved s-IP. The n-6/n-3 PUFAs ratio positively correlated with fecal zonulin levels in all subjects. These findings highlight the relationship between PUFAs and the intestinal barrier, suggesting their role in IBS-D pathophysiology and confirming the positive effects of LFD in managing IBS-D.

Nutritional safety and status following a 12-week strict low FODMAP diet in patients with irritable bowel syndrome

BACKGROUND

A low FODMAP diet (LFD) is an established dietary treatment for patients with irritable bowel syndrome (IBS). However, knowledge on the extended effects of the restriction phase regarding nutrient intake, symptom severity, and quality of life (QoL) is sparse. Therefore, our objectives were to evaluate the safety of a dietitian-led 12-week strict LFD on measures of blood biochemistry, nutritional status, symptom severity, and QoL.

METHODS

In this open-label dietitian-led 12-week strict LFD intervention for IBS patients with predominantly diarrhea or mixed stool pattern (IBS-D/-M), we collected data on diet intake (3-day dietary record), overnight fasting routine blood samples, body weight, IBS symptoms (IBS Severity Scoring System (IBS-SSS)), and IBS-related QoL (IBS-QoL) at baseline and after 12 weeks.

KEY RESULTS

Thirty-six participants completed the 12-week follow-up (mean age: 37 years, 67% women, IBS-SSS: 242 (101)). All blood parameters measured were within established reference values at both time points. We found no change in intake of macro- or micronutrients, but several micronutrients were below the recommendations both before and after 12 weeks. BMI slightly decreased, primarily driven by participants with BMI >25 (p < 0.005). QoL improved among most subdomains (p ≤ 0.002), except food avoidance and social reaction.

CONCLUSION

An extended dietitian-guided LFD (12 weeks) is not inferior to the participants' baseline diet, since no clinically meaningful changes in nutritionally related blood samples and no changes in macro- or micronutrient intake were observed. However, the intake of several nutrients was below the recommendations at both time points indicating low diet quality.

Exploration of differential responses to FODMAPs and gluten in people with irritable bowel syndrome- a double-blind randomized cross-over challenge study

INTRODUCTION

There is large variation in response to diet in irritable bowel syndrome (IBS) and determinants for differential response are poorly understood.

OBJECTIVES

Our aim was to investigate differential clinical and molecular responses to provocation with fermentable oligo-, di-, monosaccharides, and polyols (FODMAPs) and gluten in individuals with IBS.

METHODS

Data were used from a crossover study with week-long interventions with either FODMAPs, gluten or placebo. The study also included a rapid provocation test. Molecular data consisted of fecal microbiota, short chain fatty acids, and untargeted plasma metabolomics. IBS symptoms were evaluated with the IBS severity scoring system. IBS symptoms were modelled against molecular and baseline questionnaire data, using Random Forest (RF; regression and clustering), Parallel Factor Analysis (PARAFAC), and univariate methods.

RESULTS

Regression and classification RF models were in general of low predictive power (Q2 ≤ 0.22, classification rate < 0.73). Out of 864 clustering models, only 2 had significant associations to clusters (0.69 < CR < 0.73, p < 0.05), but with no associations to baseline clinical measures. Similarly, PARAFAC revealed no clear association between metabolome data and IBS symptoms.

CONCLUSION

Differential IBS responses to FODMAPs or gluten exposures could not be explained from clinical and molecular data despite extensive exploration with different data analytical approaches. The trial is registered at www.

CLINICALTRIALS

gov as NCT03653689 31/08/2018.

Evaluation of the efficacy of probiotics as treatment in irritable bowel syndrome

Irritable bowel syndrome (IBS) is a gastrointestinal functional disorder mainly characterised by abdominal pain, bloating and altered bowel habits. Dysbiosis might seem to be involved in the pathogenesis of the disease. Probiotics represent a potential treatment, since these could favour the functional microbiota and improve symptoms. The aim was to review the effectiveness of the use of probiotics in IBS symptomatology, analysing the influence of duration and dose. 18 articles were included. At the individual level, Lactobacillus, Bifidobacterium and Bacillus could be useful in the treatment of symptoms. Bifidobacterium bifidum reported the best results (1 × 109 CFU/day for 4 weeks). The most effective combination was 2 Lactobacillus strains, one of Bifidobacterium and one of Streptococcus (4 × 109 CFU/day for 4 weeks). Future clinical trials should confirm these results and analyse the difference between individual and combined treatments.

Role of Nutraceuticals in Treating Erectile Dysfunction via Inhibition of Phosphodiesterase-5 Enzyme: A Mini Review

Erectile Dysfunction (ED) is a prevalent sexual health condition affecting a significant portion of the male population worldwide. The conventional therapeutic approaches for ED often involve the use of pharmaceutical agents targeting the phosphodiesterase-5 (PDE5) enzyme. Currently, treatment with PDE-5 inhibitors is the standard approach for ED, and four PDE-5 inhibitors, namely sildenafil, vardenafil, tadalafil, and avanafil, are in use. However, these pharmaceutical interventions may be associated with adverse effects and limitations. As a result, there has been a growing interest in exploring alternative and complementary treatment options for ED, such as nutraceuticals, which are bioactive compounds derived from natural sources. Nutraceuticals, which include vitamins, minerals, herbs, and other dietary supplements, have gained popularity for their potential health benefits. Certain nutraceuticals have demonstrated the ability to modulate various physiological pathways, including those involved in erectile function. A notable mechanism of action is the inhibition of the PDE5 enzyme, which plays a pivotal role in the regulation of cGMP levels. By inhibiting PDE5, nutraceuticals can promote the accumulation of cGMP, leading to enhanced penile blood flow and improved erectile function. A comprehensive analysis of the literature showcases various nutraceutical agents, including plant-derived compounds like flavonoids, polyphenols, and amino acids which have exhibited PDE5 inhibitory effects. Mechanistic insights into their action involve modulation of NO release, cGMP elevation, and relaxation of penile smooth muscles, all critical factors for achieving and sustaining erections. This review focuses on elucidating the role of nutraceuticals in treating erectile dysfunction through the inhibition of the PDE5 enzyme.

Efficacy of diet restriction with or without probiotic for treatment of patients with IBS-D: Phase I-II clinical trial

BACKGROUND AND AIM

Diet is a major contributor to irritable bowel syndrome (IBS) and is also a powerful tool for treatment of IBS. This study compared two diets and explored the effectiveness of the diets when combined with a probiotic for treatment of IBS-D patients.

METHODS

Phase I, patients were randomized into groups; control, cold/spicy/fried restricted diet (CSF res diet), IgG positive restricted diet (IgG res diet), and a combination both diets (CSF + IgG res diet). Phase II, patients were randomized into IgG res diet + placebo and IgG res diet + probiotic. Both interventions were 12 weeks in duration. Symptom Severity Scale (IBS-D-SSS) and IgG titer were assessed at the beginning and the end of the study.

RESULTS

Totals of 214 and 167 patients completed the two parts of the study, respectively. After intervention, IBS-D-SSS and TIgG grade were significantly improved compared to baseline, with results similar to the control group. In general, there were decreases in IBS-D-SSS and TIgG grade that were significantly different among the groups. There were exceptions; no differences were observed for IBS-D-SSS between the IgG res diet and CSF + IgG res diet, or TIgG grade between the CSF res diet, IgG res diet, and CSF + IgG res diet. However, the CSF res diet and IgG res diet had a synergistic effect that decreased IBS-D-SSS and TIgG titer, with a greater contribution by the IgG res diet. Therefore, we evaluated the IgG res diet with either placebo or probiotic and found that IBS-D-SSS and TIgG grade decreased from baseline. There was a significant decrease in IBS-D-SSS with the probiotic but TIgG grade was not significantly different between the IgG diet + placebo and IgG diet + probiotic diet.

CONCLUSIONS

Both the CSF res diet and IgG res diet improved IBS symptoms and demonstrated synergy, although the IgG res diet had a greater contribution. Further, when intolerant foods cannot be eliminated from a diet, avoiding uncooked, cold, spicy, fried, and alcoholic foods is a superior choice. The IgG res diet combined with Bifidobacteria was the best dietary choice and may function though a non-IgG pathway.

Fecal microbiota transplantation in patients with post-infectious irritable bowel syndrome: A randomized, clinical trial

Introduction

Research in recent years has shown the potential benefits of fecal microbiota transplantation (FMT) for irritable bowel syndrome (IBS). Acute infectious gastroenteritis is a well-established risk factor for developing such forms of IBS as post-infectious IBS (PI-IBS). However, the effective use of FMT in patients with IP-IBS has not yet been clarified.

Aim

The study aimed to conduct a single-center, randomized clinical trial (RCT) to assess FMT’s safety, clinical and microbiological efficacy in patients with PI-IBS.

Materials and methods

Patients with PI-IBS were randomized into two groups: I (standard-care, n = 29) were prescribed basic therapy, namely a low FODMAP diet, as well as Otilonium Bromide (1 tablet TID) and a multi-strain probiotic (1 capsule BID) for 1 month; II (FMT group, n = 30), each patient with PI-IBS underwent a single FMT procedure with fresh material by colonoscopy. All patients underwent bacteriological examination of feces for quantitative and qualitative microbiota composition changes. The clinical efficacy of treatment was evaluated according to the dynamics of abdominal symptoms, measured using the IBS-SSS scale, fatigue reduction (FAS scale), and a change in the quality of life (IBS-QoL scale).

Results

FMT was associated with rapid onset of the effect, manifested in a significant difference between IBS-SSS points after 2 weeks of intervention (p < 0.001). In other time points (after 4 and 12 weeks) IBS-SSS did not differ significantly across both groups. Only after 3 months of treatment did their QoL exceed its initial level, as well value for 2 and 4 weeks, to a significant extent. The change in the ratio of the main microbial phenotypes in the form of an increase in the relative abundance of Firmicutes and Bacteroidetes was recorded in all patients after 4 weeks. It should be noted that these changes were significant but eventually normalized only in the group of PI-IBS patients who underwent FMT. No serious adverse reactions were noted.

Conclusion

This comparative study of the results of FMT use in patients with PI-IBS demonstrated its effectiveness compared to traditional pharmacotherapy, as well as a high degree of safety and good tolerability.

Peppermint essential oil: its phytochemistry, biological activity, pharmacological effect and application

Mentha (also known as peppermint), a genus of plants in the taxonomic family Lamiaceae (mint family), is widely distributed throughout temperate regions of the world. Mentha contains various constituents that are classified as peppermint essential oil (PEO) and non-essential components. PEO, consisting mainly of menthol, menthone, neomenthol and iso-menthone, is a mixture of volatile metabolites with anti-inflammatory, antibacterial, antiviral, scolicidal, immunomodulatory, antitumor, neuroprotective, antifatigue and antioxidant activities. Mounting evidence indicates that PEO may pharmacologically protect gastrointestinal, liver, kidney, skin, respiratory, brain and nervous systems, and exert hypoglycemic and hypolipidemic effects. Clinically, PEO is used for gastrointestinal and dermatological diseases, postoperative adjuvant therapy and other fields. This review aims to address the advances in the extraction and isolation of PEO, its biological activities, pharmacological effects, toxicity and applications, with an emphasis on the efficacy of PEO on burn wounds and psoriasis, providing a comprehensive foundation for research, development and application of PEO in future.

Targeted and Untargeted Mass Spectrometry-Based Metabolomics for Chemical Profiling of Three Coffee Species

While coffee beans have been studied for many years, researchers are showing a growing interest in coffee leaves and by-products, but little information is currently available on coffee species other than Coffea arabica and Coffea canephora. The aim of this work was to perform a targeted and untargeted metabolomics study on Coffea arabica, Coffea canephora and Coffea anthonyi. The application of the recent high-resolution mass spectrometry-based metabolomics tools allowed us to gain a clear overview of the main differences among the coffee species. The results showed that the leaves and fruits of Coffea anthonyi had a different metabolite profile when compared to the two other species. In Coffea anthonyi, caffeine levels were found in lower concentrations while caffeoylquinic acid and mangiferin-related compounds were found in higher concentrations. A large number of specialized metabolites can be found in Coffea anthonyi tissues, making this species a valid candidate for innovative healthcare products made with coffee extracts.

Irritable bowel syndrome and diet

PURPOSE OF REVIEW

Irritable bowel syndrome (IBS) is a highly prevalent functional gastrointestinal disorder (FGID) characterized by chronic abdominal pain and altered bowel habits. The diagnosis of IBS is based on the presence of defined clinical Rome IV criteria in the absence of alarm features. The majority of patients with IBS report of food triggers eliciting typical IBS symptoms and trying to modify their dietary intake.

RECENT FINDINGS

FGID including IBS are defined as disorders of the gut-brain interaction. A large proportion of individuals with IBS link their symptoms to dietary factors, and recent clinical studies have shown benefits of a diet low in FODMAPs (Fermentable Oligo-, Di-, and Monosaccharides and Polyols) on IBS symptoms and quality of life. Dietary interventions mediate directly changes of luminal gut contents affecting chemosensing-enteroendocrine cells in the modulation of the gut brain microbiome axis in IBS patients. Long-term assessment of clinical outcomes in patients on a low FODMAP diet is needed. Professional guidelines have incorporated the suggestion to offer IBS patients a diet low in FODMAPs.

SUMMARY

The FGIDs, including IBS, are defined as gut-brain disorders. Low FODMAP diet has been shown in clinical trials to reduce IBS symptoms but long-term efficacy and nutritional side-effects remain uncertain.

Perceptions, beliefs and behaviors of nutritional and supplementary practices in inflammatory bowel disease

Purpose

To gain insight into the behaviors, perceptions and beliefs of inflammatory bowel disease (IBD) patients nutritional and supplementary practices and also to explore perceptions and behaviors in relation to anti-inflammatory supplementation with specific emphasis on Montmorency tart cherries.

Methods

80 IBD patients completed a 16-item close-ended questionnaire which was divided into three sub-sections: baseline/demographic characteristics, disease characteristics and dietary and supplementary perceptions, beliefs and behaviors. One-sample chi-square goodness of fit tests were used for each question and two-way Pearson chi-square tests of independence were used to undertake bivariate cross-tabulation comparisons to test differences in responses to each question between baseline/demographic variables.

Results

The majority of participants (N = 40) did not follow a specific dietary pattern or use supplements (N = 56). Respondents also predominantly rated that diet can both positively (N = 66) and negatively (N = 68) influence IBD. In addition, participants rated that supplements can positively influence IBD (N = 65) and that lack of scientific evidence was the primary mechanism preventing them from utilizing supplements (N = 34). Finally, patients also strongly reported that they would be willing to take Montmorency tart cherry supplementation (N = 73).

Conclusions

The disconnect between behavior and beliefs in both diet and supplementary practices, indicate that interventions designed to translate beliefs/knowledge into behaviors are warranted. There is also a necessity to undertake well-designed intervention trials examining the efficacy of food supplements, and with patient’s willingness to take Montmorency tart cherry, there is a strong rationale for future randomized trials examining the efficacy of tart cherry supplementation in IBD.

Current status of fecal microbiota transplantation for irritable bowel syndrome

BACKGROUND

Irritable bowel syndrome (IBS) is a common gastrointestinal functional disorder. Although IBS is a benign condition, it reduces the quality of life considerably. While there is currently no effective treatment for this disorder, fecal microbiota transplantation (FMT) seems to be promising.

PURPOSE

The aim of this review was to analysis possible factors affecting the success or failure of the randomized controlled trials (RCTs) of FMT for IBS and highlighting the gaps in our knowledge that need to be filled and of sketching a possible model for successful FMT in IBS patients.

METHODS

A systematic search was conducted of literature published in English from January 2015 to December 2020 using the keywords: fecal microbiota transplantation, randomized trials, and IBS.

KEY RESULTS

Seven randomized controlled trials (RCTs) on the efficacy of FMT for IBS were found in the literature. Four of the seven RCTs found various positive effects, while the other three did not find any effect.

CONCLUSIONS AND INFERENCES

The efficacy of FMT for IBS appears to be donor-dependent. The effective (super) donor would need to have a favorable microbiota signature, and 11 clinical criteria that are known to be associated with a favorable microbiota have been suggested for selecting FMT donors for IBS. Comparing the microbiota of the effective donors with those of healthy subjects would reveal the favorable microbiota signature required for a super-donor. However, the studies reviewed were not designed to compare efficacy of different donor types. The dose of the fecal transplant is also an important factor influencing the outcome of FMT for IBS. However, further studies designed to test the effect of fecal transplant dose are needed to answer this question. Administering the fecal transplant to either the small or large intestine seems to be effective, but the optimal route of administration remains to be determined. Moreover, whether single or repeated FMT is more effective is also still unclear. A 1-year follow-up of IBS patients who received FMT showed that adverse events of abdominal pain, diarrhea, and constipation were both mild and self-limiting.

Fermentable oligo-, di-, monosaccharides, and polyols (FODMAPs), but not gluten, elicit modest symptoms of irritable bowel syndrome: a double-blind, placebo-controlled, randomized three-way crossover trial

BACKGROUND

Irritable bowel syndrome (IBS) has been associated with diets rich in fermentable oligo-, di-, monosaccharides, and polyols (FODMAPs), and gluten. Most previous studies have been single-blind and have focused on the elimination of FODMAPs or provocation with single FODMAPs. The effect of gluten is unclear, large trials isolating the effect of gluten from that of FODMAPs are needed.

OBJECTIVES

The aims of this study were to ensure high intakes of a wide range of FODMAPs, gluten, or placebo, and to evaluate the effects on IBS symptoms using the IBS-severity scoring system (IBS-SSS).

METHODS

The study was carried out with a double-blind, placebo-controlled, randomized 3-way crossover design in a clinical facility in Uppsala from September 2018 to June 2019. In all, 110 participants fulfilling the IBS Rome IV criteria, with moderate to severe IBS, were randomly assigned; 103 (90 female, 13 male) completed the trial. Throughout, IBS participants maintained a diet with minimal FODMAP content and no gluten. Participants were block-randomly assigned to 1-wk interventions with FODMAPs (50 g/d), gluten (17.3 g/d), or placebo, separated by 1-wk washout. All participants who completed ≥1 intervention were included in the intention-to-treat analysis.

RESULTS

In participants with IBS (n = 103), FODMAPs caused higher IBS-SSS scores (mean 240 [95% CI: 222, 257]) than placebo (198 [180, 215]; P = 0.00056) or gluten (208 [190, 226]; P = 0.013); no differences were found between the placebo and gluten groups (P = 1.0). There were large interindividual differences in IBS-SSS scores associated with treatment. No adverse events were reported.

CONCLUSION

In participants with IBS, FODMAPs had a modest effect on typical IBS symptoms, whereas gluten had no effect. The large interindividual differences in responses to the interventions warrant further detailed studies to identify possible underlying causes and enable individual prediction of responses. This trial was registered at www.clinicaltrials.gov as NCT03653689.

The Relieving Effects of a Polyherb-Based Dietary Supplement ColonVita on Gastrointestinal Quality of Life Index (GIQLI) in Older Adults with Chronic Gastrointestinal Symptoms Are Influenced by Age and Cardiovascular Disease: A 12-Week Randomized Placebo-Controlled Trial

Chronic gastrointestinal symptoms (CGS) negatively affect the quality of life in about 15–30% of the population without effective drugs. Recent studies suggest that dietary supplement may improve CGS, but inconsistent results exist. The goal of this study is to evaluate the effect of a polyherbal-based supplement ColonVita on the gastrointestinal quality of life index (GIQLI) in 100 old adults with CGS (63.1 ± 9.6 years) who were randomly assigned to daily ColonVita or placebo tablets (n = 50/group) for 12 weeks in a double-blind, randomized controlled trial design. No significant fibrdifferences were found between ColonVita and placebo in the baseline total GIQLI score (101.12 ± 16.87 vs. 101.80 ± 16.48) (P > 0.05) or postintervention total GIQLI score (114.78 ± 9.62 vs. 111.74 ± 13.01) (P > 0.05). However, ColonVita significantly improved 16 scores of the 19 core GI symptoms compared with 10 items improved by placebo. The ColonVita group significantly improved the remission rate of 5 core GI symptoms compared to placebo and significantly improved the total GIQLI scores (118.09 ± 7.88 vs. 109.50 ± 16.71) (P < 0.05) and core GI symptom scores (64.61 ± 3.99 vs. 60.00 ± 8.65) (P < 0.05) in people ≥60 years of age (n = 49) but not in those under 60 y (n = 51). ColonVita significantly improved the total GIQLI scores and core GI symptom scores in people without cardiovascular diseases (CVD) (n = 56) (116.74 ± 9.38 vs. 110.10 ± 14.28) (P < 0.05) and (63.11 ± 4.53 vs. 59.93 ± 8.03) (P=0.07), respectively, but not in those with CVD (n = 44). Thus, ColonVita was beneficial for old adults with CGS, especially those ≥60 years of age and without CVD. Because a heterogenous pathogenesis of CGS-like irritable bowel syndrome (IBS) and inflammatory bowel disease (ISD) is differentially associated with CVD, different comorbidities may have influenced the outcomes of different trials that should be controlled in further studies.

An Update on the Assessment and Management of Pediatric Abdominal Pain

Chronic abdominal pain is very common in children and adolescent and results in high personal and social costs. Most youth with chronic abdominal pain fulfill criteria for a functional abdominal pain disorder (FAPD) as defined by Rome criteria. These are complex conditions with a wide array of biological, psychological, and social factors contributing to the experience of pain. The purpose of the current review is to provide an overview of the pathophysiology of FAPDs and an up-to-date summary of the literature related to FAPDs in children and adolescents, with additional focus on several areas (eg, diet and probiotics) where patients and families frequently have questions or implement self-directed care. We also provide an approach to the assessment and treatment of pediatric FAPDs focusing on the robust literature regarding psychological interventions and much sparser literature regarding medication treatment.

Impact of food-derived bioactive peptides on gut function and health

The gastrointestinal tract (GIT) is the largest interface between our body and the environment. It is an organ system extending from the mouth to the anus and functions for food intake, digestion, transport and absorption of nutrients, meanwhile providing protection from environmental factors, like toxins, antigens, and pathogens. Diet is one of the leading factors modulating the function of the GIT. Bioactive peptides presenting naturally in food or derived from food proteins during digestion or processing have been revealed multifunctional in diverse biological processes, including maintaining gut health and function. This review summarizes the available evidence regarding the effects of food-derived bioactive peptides on gut function and health. Findings and insights from studies based on in vitro and animal models are discussed. The gastrointestinal mucosa maintains a delicate balance between immune tolerance to nutrients and harmful components, which is crucial for the digestive system's normal functions. Dietary bioactive peptides positively impact gastrointestinal homeostasis by modulating the barrier function, immune responses, and gut microbiota. However, there is limited clinical evidence on the safety and efficacy of bioactive peptides, much less on the applications of dietary peptides for the treatment or prevention of diseases related to the GIT. Further study is warranted to establish the applications of bioactive peptides in regulating gut health and function.

Modern aspects of the management of patients with irritable bowel syndrome

A review of modern data from the study of functional disorders of the digestive tract is performed. In the United States, 4 million people with functional bowel disorders seek medical care annually, and the annual cost of managing these patients is $ 358 million. Due to the urgency of the problem, new developments appear, among which it is necessary to highlight the American College of Gastroenterology (ACG) guidelines for the management of patients with IBS. To examine patients with suspected IBS, the authors of the ACG guideline proposed a positive diagnostic strategy, which is based on a careful study of the anamnesis, focusing on the key symptoms of the relationship between abdominal pain and bowel function during a long course of the disease (more than 6 months) and the absence of alarming symptoms with minimal use of instrumental diagnostic tests. For the diagnosis of IBS, the  authors recommended serological testing for  celiac disease, determination of  fecal calprotectin  and C-reactive protein  to exclude inflammatory bowel diseases, but they did not consider it necessary to routinely analyze stool for intestinal pathogens. From our point of view, the absence of routine stool analysis for intestinal pathogens is completely inapplicable for Russia, since in our country the frequency of detection of diphyllobothriasis, giardiasis and opisthorchiasis is very high. The ACG consensus drew attention to the need to expand the evidence base for the use of some standard drugs for the treatment of IBS, proposed a number of new drugs (lebiprostone, linaclotide), recommended the use of rifaximin (for the treatment of IBS with a predominance of diarrhea) and tricyclic antidepressants (for the treatment of IBS). Analysis of modern international recommendations suggests that the clinical guidelines of the Russian Gastroenterological Association and the Association of Coloproctologists of Russia for the diagnosis and treatment of IBS are currently the main document governing the management of these patients in our country.

Of bowels, brain and behavior: A role for the gut microbiota in psychiatric comorbidities in irritable bowel syndrome

BACKGROUND

The gastrointestinal microbiota has emerged as a key regulator of gut-brain axis signalling with important implications for neurogastroenterology. There is continuous bidirectional communication between the gut and the brain facilitated by neuronal, endocrine, metabolic, and immune pathways. The microbiota influences these signalling pathways via several mechanisms. Studies have shown compositional and functional alterations in the gut microbiota in stress-related psychiatric disorders. Gut microbiota reconfigurations are also a feature of irritable bowel syndrome (IBS), a gut-brain axis disorder sharing high levels of psychiatric comorbidity including both anxiety and depression. It remains unclear how the gut microbiota alterations in IBS align with both core symptoms and these psychiatric comorbidities.

METHODS

In this review, we highlight common and disparate features of these microbial signatures as well as the associated gut-brain axis signalling pathways. Studies suggest that patients with either IBS, depression or anxiety, alone or comorbid, present with alterations in gut microbiota composition and harbor immune, endocrine, and serotonergic system alterations relevant to the common pathophysiology of these comorbid conditions.

KEY RESULTS

Research has illustrated the utility of fecal microbiota transplantation in animal models, expanding the evidence base for a potential causal role of disorder-specific gut microbiota compositions in symptom set expression. Moreover, an exciting study by Constante and colleagues in this issue highlights the possibility of counteracting this microbiota-associated aberrant behavioral phenotype with a probiotic yeast, Saccharomyces boulardii CNCM I-745.

CONCLUSIONS AND INFERENCES

Such data highlights the potential for therapeutic targeting of the gut microbiota as a valuable strategy for the management of comorbid psychiatric symptoms in IBS.

Dietary interventions and irritable bowel syndrome - what really works?

PURPOSE OF REVIEW

The review examines the latest research on the use of dietary interventions in the management of irritable bowel syndrome (IBS) in order to understand what is the evidence supporting the efficacy of a dietary approach in this disorder.

RECENT FINDINGS

A general dietary advice should be offered to all IBS patients. Psyllium supplementation is recommended in IBS with both constipation and diarrhea predominance. There is increasing evidence showing the beneficial effects of a low fermentable oligo-, di-, monosaccharides, and polyols (FODMAP) diet (LFD) on IBS symptoms. FODMAPs that are well tolerated should be reintroduced in daily diet, to increase acceptability of the diet, and limit potentially harmful effects. The benefits observed with the gluten-free diet seem determined by the reduction of FODMAPs rather than gluten. Modulation of gut microbiota using probiotics shows promising results, but there are unanswered questions regarding the optimal strains, dose and duration of treatment. Additional evidence is also needed for the role of prebiotics and synbiotics in IBS.

SUMMARY

Food is both trigger of IBS symptoms and therapeutic tool. Recent studies demonstrated the beneficial effects of LFD on symptom control, as well as the role of probiotics, which seem to contribute to gut health and function.

Nopal fiber (Opuntia ficus-indica) improves symptoms in irritable bowel syndrome in the short term: a randomized controlled trial

BACKGROUND

Clinical guidelines provide limited and conflicting recommendations regarding dietary fiber supplementation in irritable bowel syndrome (IBS). Nopal (Opuntia ficus-indica) is a cactus plant fiber containing both insoluble and soluble fibers that may have therapeutic potential in IBS. Our aim was to evaluate the dose-response effect of extracted nopal fiber powder on symptoms in IBS.

METHODS

We performed a 4-arm, double-blind, parallel, randomized controlled trial in 60 patients fulfilling Rome IV criteria for IBS. Patients were randomized and blindly allocated to receive either nopal fiber (10, 20, or 30 g/day) or placebo (30 g/day dextrose) for one week and to keep their usual diet. Symptom severity (Global Symptom Question, IBS-SSS, Gastrointestinal Symptom Rating Scale), stool frequency and consistency (Bristol Stool Form Scale), breath hydrogen response, and stool short-chain fatty acids (SCFA) were measured at baseline and follow-up.

KEY RESULTS

Significantly more patients reported adequate relief of symptoms after 20 g/day (87%, p = 0.008) and 30 g/day (80%, p = 0.025) of nopal fiber compared to placebo (33%). More patients receiving 20 g/day nopal fiber (67%) had a > 50% reduction in IBS-SSS compared to placebo (20%, p = 0.027), whereas the 30 g/day dose induced more loose stools (p = 0.027). Response rates were similar among IBS subtypes. There were no differences in breath hydrogen or stool SCFA between groups.

CONCLUSIONS AND INFERENCES

Nopal fiber supplementation at doses of 20 and 30 g/day was associated with short-term improvement in IBS symptoms, warranting a fully powered clinical trial of longer duration with symptomatic, physiological, and microbiological endpoints.