Effects of Bifidobacterium longum 35624 in Children and Adolescents with Irritable Bowel Syndrome.

Irritable bowel syndrome (IBS) and vitamin D deficiency are common among children in Latin America. Previous studies show that Bifidobacterium longum35624TM improves IBS symptoms in adults. This real-world, single-arm, open-label study conducted in Chile investigated the effects of B. longum 35624 (1 × 109 colony-forming units, 12 weeks) on gastrointestinal symptoms (adapted IBS severity scoring system [IBS-SSS]; adapted Questionnaire on Pediatric Gastrointestinal Symptoms [QPGS], and Bristol Stool Form Scale) in 64 children and adolescents (8-18 years) and explored the relationship with baseline vitamin D status. Improvements in all IBS-SSS domains and composite score were observed at week 6 and 12 (p < 0.0007 versus baseline), with 98.3% of participants experiencing numerical improvements in ≥3 domains. Clinically meaningful improvement was seen in 96.6% of participants. The distribution of IBS-SSS severity categories shifted from moderate/severe at baseline to mild/remission (p < 0.0001). Improvements were not maintained during the two-week washout. Low baseline serum vitamin D levels did not correlate to IBS severity or probiotic response. QPGS significantly decreased from baseline to week 6 (p = 0.0005) and 12 (p = 0.02). B. longum 35624 may improve IBS symptoms in children and adolescents, even those with vitamin D deficiency. A confirmatory randomized controlled trial and further exploration of probiotic response and vitamin D status are needed.

Challenges of recruitment processes to a randomized dietary trial in irritable bowel syndrome.

Background: Irritable bowel syndrome (IBS) is common with a global prevalence of 4%. Dietary regimes with a low content of fermentable oligo-, di-, and monosaccharides and polyol (FODMAP) or a starch- and sucrose-reduced diet (SSRD) have proven to be efficient. The aim of the present study was to describe the recruitment process for a randomized dietary trial with low FODMAP or SSRD for 4 weeks with a follow-up period of 5 months. The results of the dietary trial itself are not included in this paper but will be presented in another publication. Methods: The County of Skåne, with 1,41 million inhabitants, was used as a base to perform a dietary trial in which IBS patients, age 18-70 years, were randomized to either low FODMAP or SSRD for 4 weeks. The estimated number of IBS patients in the actual age span was approximately 32,000. The trial was announced through lectures, letters to all primary healthcare centers (n=203), social media (two campaigns), and invitations to IBS patients identified in medical records (n=744). Results: Three referrals arrived from the healthcare system, 17 patients contacted the investigators in person after receiving information from their healthcare center, and four patients contacted the investigators after recommendations from friends. Of these, 14 were enrolled in the study. From social media, 218 names were delivered, of which 93 fulfilled the study criteria and were willing to participate when contacted by the investigators (42.7%). Of the 3587 identified IBS patients in medical records in close proximity to the hospital, 744 were randomly contacted. Forty-eight patients (6.5 %) were willing to be included in the study. Thus, 155 patients with IBS were included in this study. Conclusions: The inclusion rate for dietary intervention was very low considering the large population informed about the study. Announcements on social media seem to be the best way to recruit patients for intervention. Trial registration: NCT05192603, 29/11/2021, ClinicalTrials.gov. The PRS URL is https://register.clinicaltrials.gov.

Current and future pharmacotherapies for the management of constipation-predominant irritable bowel syndrome.

INTRODUCTION: Irritable bowel syndrome (IBS) is a common gastrointestinal disorder affecting 9-23% of the world's population, with a higher prevalence among women. IBS is a complex disorder influenced by psychosocial, physiological, and genetic factors, exacerbated by stress. AREAS COVERED: Research confirms that the most common subtype of IBS is IBS-C. Therefore, new therapies are being developed to speed up bowel movement and reduce constipation, with drugs such as linaclotide, plecanatide, lubiprostone, or tegaserod available to reduce IBS-C symptoms. In addition, patients' condition is improved by foods rich in fiber and low in FODMAP and the use of biotics. EXPERT OPINION: The topic is of great importance due to the growing number of patients suffering from IBS-C and its significant impact on quality of life. Current clinical trials of new therapeutic options are not too successful, and it seems that one of the plausible treatment options could be the multi-drug cocktail with some, or perhaps even all its ingredients emerging from drug re-purposing. Another important path that needs to be explored further in IBS-C patients is the adjustment of dietary habits and/or introduction of dietary or nutritional intervention.

Irritable bowel syndrome: Clinical practice update.

ABSTRACT: Irritable bowel syndrome (IBS) is a common and burdensome disorder characterized by chronic recurrent abdominal pain and altered bowel habits. IBS remains misunderstood, leading to delayed diagnosis, impaired quality of life, and substantial healthcare costs. Advancing clinicians' understanding of this complex biopsychosocial process, using a positive diagnostic strategy rather than a diagnosis of exclusion, and incorporating a multimodal treatment approach expedite time to diagnosis, facilitate symptom relief, and reduce financial expenditure.

Gut microbial signatures of patients with diarrhea-predominant irritable bowel syndrome and their healthy relatives.

AIMS: Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disorder, encompassing diarrhea-predominant irritable bowel syndrome (IBS-D). Here, we utilized 16S rDNA gene sequencing to identify potential microbial drivers of IBS-D. METHODS AND RESULTS: A total of 30 healthy relatives and 27 patients with IBS-D were recruited. Clinical data and fecal samples were collected from patients and controls. 16S rDNA gene sequencing was performed to obtain fecal bacterial data. Differences in community composition were evaluated utilizing analysis of similarity (ANOSIM) using Bray-Curtis dissimilarity. The Wilcoxon rank sum test was used to compare differences in taxa and functional pathways. Finally, the key gut microbiota was identified using the random forest algorithm. Gut microbiota diversity, estimated through the Observe, Chao1, and abundance-based coverage estimator (ACE) indices, was significantly lower in the IBS-D patients than in the healthy relatives. ANOSIM analysis further confirmed significant differences in the composition of the gut microbiota between IBS-D patients and healthy relatives, with an R value of 0.106 and a P-value of 0.005. Notably, the IBS-D patients exhibited a significant enrichment of specific bacterial genera, including Fusicatenibacter, Streptococcus, and Klebsiella, which may possess potential pathogenic properties. In particular, the bacterial genus Klebsiella demonstrated a positive correlation with irritable bowel syndrome severity scoring system scores. Conversely, healthy subjects showed enrichment of bacterial genera such as Alistipes, Akkermansia, and Dialister, which may be beneficial bacteria in IBS-D. Utilizing the random forest model, we developed a discriminative model for IBS-D based on differential bacterial genera. This model exhibited impressive performance, with an area under the curve value of 0.90. Additionally, our analysis did not reveal any gender-specific differences in the microbiota community composition among IBS-D patients. CONCLUSIONS: Our findings offer preliminary insights into the potential relationship between intestinal microbiota and IBS-D. The identification model for IBS-D, grounded in gut microbiota, holds promising prospects for improving early diagnosis of IBS-D.

Archaea influence composition of endoscopically visible ileocolonic biofilms.

The gut microbiota has been implicated as a driver of irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). Recently we described, mucosal biofilms, signifying alterations in microbiota composition and bile acid (BA) metabolism in IBS and ulcerative colitis (UC). Luminal oxygen concentration is a key factor in the gastrointestinal (GI) ecosystem and might be increased in IBS and UC. Here we analyzed the role of archaea as a marker for hypoxia in mucosal biofilms and GI homeostasis. The effects of archaea on microbiome composition and metabolites were analyzed via amplicon sequencing and untargeted metabolomics in 154 stool samples of IBS-, UC-patients and controls. Mucosal biofilms were collected in a subset of patients and examined for their bacterial, fungal and archaeal composition. Absence of archaea, specifically Methanobrevibacter, correlated with disrupted GI homeostasis including decreased microbial diversity, overgrowth of facultative anaerobes and conjugated secondary BA. IBS-D/-M was associated with absence of archaea. Presence of Methanobrevibacter correlated with Oscillospiraceae and epithelial short chain fatty acid metabolism and decreased levels of Ruminococcus gnavus. Absence of fecal Methanobrevibacter may indicate a less hypoxic GI environment, reduced fatty acid oxidation, overgrowth of facultative anaerobes and disrupted BA deconjugation. Archaea and Ruminococcus gnavus could distinguish distinct subtypes of mucosal biofilms. Further research on the connection between archaea, mucosal biofilms and small intestinal bacterial overgrowth should be performed.

Is the Mediterranean Low Fodmap Diet Effective in Managing Irritable Bowel Syndrome Symptoms and Gut Microbiota? An Innovative Research Protocol.

INTRODUCTION: Irritable bowel syndrome (IBS) symptoms can be effectively managed with the low FODMAP diet. However, its efficacy in reducing inflammation is not yet proven. On the contrary, the Mediterranean diet has anti-inflammatory properties with proven efficacy in treating chronic low-grade inflammation-related diseases. AIM: To publicly share our protocol evaluating the efficacy of the Mediterranean low-FODMAP (MED-LFD) versus NICE recommendations (British National Institute for Health and Care Excellence) diet in managing IBS symptoms and quality of life. MATERIALS AND METHODS: Participants meeting the Rome IV criteria will be randomly assigned to MED-LFD or NICE recommendations and they will be followed for six months. Efficacy, symptom relief, quality of life and mental health will be assessed using validated questionnaires. In addition, fecal samples will be analyzed to assess gut microbiota, and to measure branched and short-chain fatty acids, and volatile organic compounds (metabolic byproducts from bacteria). Expected results and discussion: By publicly sharing this clinical study protocol, we aim to improve research quality in the field of IBS management by allowing for peer review feedback, preventing data manipulation, reducing redundant research efforts, mitigating publication bias, and empowering patient decision-making. We expect that this protocol will show that MED-LFD can effectively alleviate IBS symptoms and it will provide pathophysiology insights on its efficacy. The new dietary pattern that combines the LFD and the MED approaches allows for the observation of the synergistic action of both diets, with the MED's anti-inflammatory and prebiotic properties enhancing the effects of the LFD while minimizing its limitations. Identifier in Clinical Trials: NCT03997708.

Atractylodes macrocephala Koidz Alleviates Symptoms in Zymosan-Induced Irritable Bowel Syndrome Mouse Model through TRPV1, NaV1.5, and NaV1.7 Channel Modulation.

(1) Background: Irritable bowel syndrome (IBS) is a common disease in the gastrointestinal (GI) tract. Atractylodes macrocephala Koidz (AMK) is known as one of the traditional medicines that shows a good efficacy in the GI tract. (2) Methods: We investigated the effect of AMK in a network pharmacology and zymosan-induced IBS animal model. In addition, we performed electrophysiological experiments to confirm the regulatory mechanisms related to IBS. (3) Results: Various characteristics of AMK were investigated using TCMSP data and various analysis systems. AMK restored the macroscopic changes and weight to normal. Colonic mucosa and inflammatory factors were reduced. These effects were similar to those of amitriptyline and sulfasalazine. In addition, transient receptor potential (TRP) V1, voltage-gated Na+ (NaV) 1.5, and NaV1.7 channels were inhibited. (4) Conclusion: These results suggest that AMK may be a promising therapeutic candidate for IBS management through the regulation of ion channels.

Changes in Fecal Short-Chain Fatty Acids in IBS Patients and Effects of Different Interventions: A Systematic Review and Meta-Analysis.

CONTEXT: Short-chain fatty acids (SCFAs) have been reported to be associated with the pathogenesis of irritable bowel syndrome (IBS), but the results are conflicting. OBJECTIVE: Here, a systematic review of case-control studies detecting fecal SCFAs in IBS patients compared with healthy controls (HCs) and self-controlled studies or randomized controlled trials (RCTs) investigating fecal SCFA alterations after interventions were identified from several databases. DATA SOURCES: A systematic search of databases (PubMed, Web of Science, and Embase) identified 21 studies published before 24 February 2023. Data extractions: Three independent reviewers completed the relevant data extraction. DATA ANALYSIS: It was found that the fecal propionate concentration in IBS patients was significantly higher than that in HCs, while the acetate proportion was significantly lower. Low-FODMAP diets significantly reduced the fecal propionate concentration in the IBS patients while fecal microbiota transplantation and probiotic administration did not significantly change the fecal propionate concentration or acetate proportion. CONCLUSIONS: The results suggested that the fecal propionate concentration and acetate proportion could be used as biomarkers for IBS diagnosis. A low-FODMAP diet intervention could potentially serve as a treatment for IBS while FMT and probiotic administration need more robust trials.

Unresolved conundrum of the role of physical activity in inflammatory bowel disease: What next?

There is considerable controversy on the role of physical activity in irritable bowel disease (IBD) since published reports are conflicting. It is well known that there is known relapse with specific treatment in IBD. This, in addition to onset of extraintestinal symptoms creates a need to think of alternate approaches. In this context, the current article describes the need of a multi-institutional study with standard protocol of physical activity for documenting its effect on both the primary disease and the extra alimentary manifestations. This paper also points out the possibility of using adjuvant complementary medicine such as yoga, whose effects have been documented in other diseases like irritable bowel syndrome. A third approach could be to focus on the intestinal dysbiosis in IBD and concentrate on research on restoring the microbial flora to normal, to see whether the extra-intestinal symptoms are alleviated.

The Microbiome and Irritable Bowel Syndrome: An Emerging Hope for Treatment.

Irritable bowel syndrome is a gastrointestinal disorder that affects 15%-20% of the US population. Its symptoms can have negative effects on a person's quality of life, and its treatment can be associated with high medical costs. An emerging area of irritable bowel syndrome research concerns the relationship between this condition and the gut microbiome. The purpose of this article is not only to review irritable bowel syndrome, and the role that the microbiome can play in its symptoms, but also to examine new emerging pathways that could blaze the trail for more individualized treatments. If equipped with this knowledge, gastrointestinal nurses and providers of care can be better prepared to help patients with irritable bowel syndrome in order to manage symptoms and improve their quality of life.

How to understand the overlap of long COVID, chronic fatigue syndrome/myalgic encephalomyelitis, fibromyalgia and irritable bowel syndromes.

Long COVID should be limited to patients with multiple, persistent symptoms not related to well-defined organ damage. Once redefined, a focused review of long COVID demonstrates striking similarity to chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME), fibromyalgia (FM) and irritable bowel syndrome (IBS). Research in long COVID has revealed similar findings to those noted in CFS/ME and FM, characterized by central nervous system organ dysfunction. Long COVID, like CFS/ME, FM and IBS, is best understood as a bidirectional mind-body, neuroimmune illness.

Factors associated with having previously received a diagnosis of fibromyalgia, chronic fatigue syndrome and irritable bowel syndrome: A cross sectional DanFunD study.

OBJECTIVES: Fibromyalgia, chronic fatigue syndrome, and irritable bowel syndrome are highly prevalent conditions and part of the functional somatic syndromes (FSS) diagnosis, that are classified under the unifying umbrella term functional somatic disorder (FSD). Multiple factors are associated with FSD symptom development; However, few studies have explored these associations in relation to the diagnosis status. This study aims to examine associations with a previously received FSS diagnosis from a physician in participants fulfilling the FSD diagnostic criteria in a population-based sample. METHODS: This research employs a comprehensive observational approach using a cross sectional design with data from the DanFunD part two cohort. Information about received FSS diagnoses was obtained from self-reported questionnaires. Participants fulfilling the FSD diagnostic criteria were identified with both self-reported questionnaires and diagnostic interviews. Validated questionnaires were used to assess the examined factors. RESULTS: 1704 cases fulfilled the diagnostic criteria for an FSD according to questionnaires or interviews in the DanFunD study. In participants fulfilling the diagnostic criteria, having previously received an FSS diagnosis by a physician was strongly associated with female sex, negative illness perceptions and poor health-related quality of life for questionnaire and interview-based diagnoses. Less consistent associations were observed for lower socioeconomic status, anxiety, and adverse life events. CONCLUSION: Previously received FSS diagnoses showed associations with multiple factors with a particular strong association with female sex and poor health related quality of life.

Mechanisms of Peitu Yimu acupuncture in repairing intestinal mucosal barrier by regulating CRF/CRFR1 pathway in diarrhea-predominant irritable bowel syndrome rats. / 培土抑木针法调节CRF/CRFR1é€šè·¯ä¿®å¤è ¹æ³»åž‹è‚ æ˜“æ¿€ç»¼åˆå¾å¤§é¼ è‚ é»è†œå±éšœçš„æœºåˆ¶ç ”ç©¶.

OBJECTIVES: To investigate the effect of Peitu Yimu(strengthening spleen and soothing liver) acupuncture on intestinal mucosal barrier function and corticotropin-releasing factor (CRF)/CRF receptor 1 (CRFR1) pathway in rats with diarrhea-predominant irritable bowel syndrome (IBS-D), so as to explore its underlying mechanism in alleviating IBS-D. METHODS: Forty female SD rats were randomly divided into blank, model, electroacupuncture (EA), and agonist groups, with 10 rats in each group. Except for the blank group, rats in the other groups were given folium sennae infusion by gavage combined with chronic unpredictable mild stress to establish IBS-D model. Rats in the EA group received acupuncture at "Tianshu"(ST25) and EA at "Zusanli"(ST36) and "Taichong"(LR3) (2 Hz/15 Hz) on one side for 20 min, with the side chosen alternately every other day, for 14 days after modeling. Rats in the agonist group received acupuncture 30 min after intravenous injection of CRFR1 agonist urocortin, with the same manipulation method and time as the EA group. Before and after intervention, visceral pain threshold and stool Bristol scores were measured. Elevated plus maze test and open field test were used to detect anxiety and depression like behavior of rats. ELISA was used to detect the contents of CRF and CRFR1 in rats serum. Immunohistochemistry was used to detect the positive expressions of CRF, CRFR1, zonula occludens protein 1(ZO-1), occlusal protein(Occludin), and closure protein 1 (Claudin-1) in colon tissue. RESULTS: Compared with the blank group, the visceral pain threshold, open arm time percentage (OT%), total distance of movement in the open field test, and positive expression of ZO-1, Occludin, and Claudin-1 in colon were decreased (P<0.01, P<0.05), while Bristol stool scores, serum CRF and CRFR1 contents, and positive expressions of CRF and CRFR1 in colon were increased (P<0.01) in the model group. After intervention and compared with the model group, the visceral pain threshold, OT%, total distance of movement in the open field test, and positive expressions of ZO-1, Occludin, and Claudin-1 in colon were increased (P<0.05, P<0.01), while Bristol stool scores, serum CRF and CRFR1 contents, and positive expressions of CRF and CRFR1 in colon were decreased (P<0.01) in the EA group；the Bristol stool scores, serum CRF content, and CRF positive expression in colon were significantly decreased in the agonist group (P<0.01). CONCLUSIONS: Peitu Yimu acupuncture can significantly improve visceral hypersensitivity and anxiety-depression state in IBS-D rats. Its mechanism may be related to the inhibition of CRF/CRFR1 pathway and restoration of intestinal tight junction protein expressions.

Physical activity, sedentary behavior, and the risk of functional gastrointestinal disorders: A two-sample Mendelian randomization study.

OBJECTIVES: Functional dyspepsia (FD) and irritable bowel syndrome (IBS) are prevalent functional gastrointestinal disorders (FGIDs). In this study we aimed to explore the causal association between physical activity or sedentary behavior and the risk of FD and IBS. METHODS: Mendelian randomization (MR) analysis was employed. Candidate genetic instruments for physical activity and sedentary behavior were retrieved from the latest published Genome-Wide Association Study (GWAS), which included up to 703 901 participants. Summary-level GWAS data for FD (8 875 cases and 320 387 controls) and IBS (9 323 cases and 301 931 controls) were obtained from the FinnGen study. The causal effects were mainly estimated by inverse variance weighted (IVW) method. Sensitivity analyses were implemented with Cochran's Q test, MR-Egger intercept test, leave-one-out analysis, and the funnel plot. RESULTS: No significant association of moderate-to-vigorous intensity physical activity (MVPA), leisure screen time (LST), sedentary behavior at work (SDW), and sedentary commuting (SDC) with the risk of FD was found. However, there was a suggestive correlation between MVPA and the decreased risk of FD (odds ratio [OR] 0.63, 95% confidence interval [CI] 0.39-0.99, P = 0.047). Genetically predicted MVPA decreased the risk of IBS (OR 0.58, 95% CI 0.40-0.84, P = 0.004), while increased LST was positively associated with IBS risk (OR 1.33, 95% CI 1.15-1.53, P < 0.001). No causal effects of SDW or SDC on IBS risk were observed. CONCLUSION: MVPA and LST are causally linked to the development of IBS, which will facilitate primary prevention of IBS.

Postprandial symptoms in disorders of gut-brain interaction and their potential as a treatment target.

Postprandial, or meal-related, symptoms, such as abdominal pain, early satiation, fullness or bloating, are often reported by patients with disorders of gut-brain interaction, including functional dyspepsia (FD) or irritable bowel syndrome (IBS). We propose that postprandial symptoms arise via a distinct pathophysiological process. A physiological or psychological insult, for example, acute enteric infection, leads to loss of tolerance to a previously tolerated oral food antigen. This enables interaction of both the microbiota and the food antigen itself with the immune system, causing a localised immunological response, with activation of eosinophils and mast cells, and release of inflammatory mediators, including histamine and cytokines. These have more widespread systemic effects, including triggering nociceptive nerves and altering mood. Dietary interventions, including a diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols, elimination of potential food antigens or gluten, IgG food sensitivity diets or salicylate restriction may benefit some patients with IBS or FD. This could be because the restriction of these foods or dietary components modulates this pathophysiological process. Similarly, drugs including proton pump inhibitors, histamine-receptor antagonists, mast cell stabilisers or even tricyclic or tetracyclic antidepressants, which have anti-histaminergic actions, all of which are potential treatments for FD and IBS, act on one or more of these mechanisms. It seems unlikely that food antigens driving intestinal immune activation are the entire explanation for postprandial symptoms in FD and IBS. In others, fermentation of intestinal carbohydrates, with gas release altering reflex responses, adverse reactions to food chemicals, central mechanisms or nocebo effects may dominate. However, if the concept that postprandial symptoms arise from food antigens driving an immune response in the gastrointestinal tract in a subset of patients is correct, it is paradigm-shifting, because if the choice of treatment were based on one or more of these therapeutic targets, patient outcomes may be improved.

Rapid biotransformation of STW 5 constituents by human gut microbiome from IBS- and non-IBS donors.

STW 5, a blend of nine medicinal plant extracts, exhibits promising efficacy in treating functional gastrointestinal disorders, notably irritable bowel syndrome (IBS). Nonetheless, its effects on the gastrointestinal microbiome and the role of microbiota on the conversion of its constituents are still largely unexplored. This study employed an experimental ex vivo model to investigate STW 5's differential effects on fecal microbial communities and metabolite production in samples from individuals with and without IBS. Using 560 fecal microcosms (IBS patients, n = 6; healthy controls, n = 10), we evaluated the influence of pre-digested STW 5 and controls on microbial and metabolite composition at time points 0, 0.5, 4, and 24 h. Our findings demonstrate the potential of this ex vivo platform to analyze herbal medicine turnover within 4 h with minimal microbiome shifts due to abiotic factors. While only minor taxonomic disparities were noted between IBS- and non-IBS samples and upon treatment with STW 5, rapid metabolic turnover of STW 5 components into specific degradation products, such as 18ß-glycyrrhetinic acid, davidigenin, herniarin, 3-(3-hydroxyphenyl)propanoic acid, and 3-(2-hydroxy-4-methoxyphenyl)propanoic acid occurred. For davidigenin, 3-(3-hydroxyphenyl)propanoic acid and 18ß-glycyrrhetinic acid, anti-inflammatory, cytoprotective, or spasmolytic activities have been previously described. Notably, the microbiome-driven metabolic transformation did not induce a global microbiome shift, and the detected metabolites were minimally linked to specific taxa. Observed biotransformations were independent of IBS diagnosis, suggesting potential benefits for IBS patients from biotransformation products of STW 5. IMPORTANCE: STW 5 is an herbal medicinal product with proven clinical efficacy in the treatment of functional gastrointestinal disorders, like functional dyspepsia and irritable bowel syndrome (IBS). The effects of STW 5 on fecal microbial communities and metabolite production effects have been studied in an experimental model with fecal samples from individuals with and without IBS. While only minor taxonomic disparities were noted between IBS- and non-IBS samples and upon treatment with STW 5, rapid metabolic turnover of STW 5 components into specific degradation products with reported anti-inflammatory, cytoprotective, or spasmolytic activities was observed, which may be relevant for the pharmacological activity of STW 5.

[Gastrointestinal symptoms and dietary intake of patients with irritable bowel syndrome following a low FODMAP diet].

INTRODUCTION: High FODMAP (fermentable oligo-, di, monosaccharides and polyols) foods have been linked with worsening symptoms of IBS patients. The aim was to compare gastrointestinal symptoms and dietary intake of patients with irritable bowel syndrome following a low FODMAP diet, with or without individual nutrition therapy. MATERIALS AND METHODS: A total of 54 patients that met Rome IV criteria for IBS were randomized into two groups, guided group (individual nutrition therapy, n=28) and self-management group (learned about low FODMAP diet online, n=26). Both groups followed low FODMAP diet for 4 weeks. Four-day food records were used to assess dietary intake. Symptoms were assessed by the IBS-severity scoring system (ISB-SSS). RESULTS: The number of subjects who did not complete the study was 13, thereof five in the nutrition therapy and eight in the self-management group, leaving 23 and 18 subjects available for analysis, respectively. Symptoms declined from baseline to endpoint in both groups, by 183±101 points on average in the group receiving nutrition therapy (p< 0.001) and 132±110 points in the self-management group (p< 0.001), with no difference between groups. At baseline, about 80% of meals in both groups contained food high in FODMAP's. The corresponding proportion was 9% and 36% in week 3 in the nutrition therapy and self-management group, respectively (p< 0.001). CONCLUSION: Both groups experienced relieve of symptoms, but compliance to the low FODMAP diet was better in the group receiving individual nutrition therapy compared with the group who only received instructions on how to learn about low FODMAP diet online.

The impact of depression-mediated gut microbiota composition on Irritable Bowel Syndrome: A Mendelian study.

OBJECTIVE: This study uses a two-sample Mendelian randomization (MR) analysis to delineate the causal influence of gut microbiota on the occurrence of irritable bowel syndrome (IBS), concurrently assessing the potential mediating function of depression within this framework. METHODS: Several two-sample MR methods were used to assess the causal repercussions of gut microbiota on the onset of both IBS and depression. Following this, gut microbiota and depression, which demonstrated notable causal associations, were integrated as exposure variables in a multivariable Mendelian randomization (MVMR) framework to construct a model encompassing gut microbiota, depression, and IBS. Mediation effects were assessed by examining the indirect pathway of gut microbiota → depression → IBS. RESULTS: Two-sample MR analysis unveiled a statistically significant causal association (P < 0.05) between specific bacterial group within the gut microbiota, notably p_Actinobacteria(OR = 0.829225), c_Clostridia(OR = 0.798897), s_Desulfovibrio_piger(OR = 1.163912), g_Streptococcus(OR = 1.132735), c_Actinobacteria(OR = 0.829224), and the onset of IBS. In the MVMR analysis, the relationship between depression and IBS was significant across Model 3, Model 7, Model 8, and Model 13 (P < 0.05). Assessment of mediation effects revealed that c_Clostridia and o_Clostridiales indirectly impacted IBS through depression, with masking effect ratios of 168.46 % and 168.44 %, respectively. CONCLUSION: These findings underscore a resilient causal association between the composition of gut microbiota and the initiation of IBS. Furthermore, depression serves as a mediator for particular groups of gut bacteria, thereby contributing to the development of IBS. These observations imply that interventions targeting mental health may potentially alleviate the risk of IBS onset attributable to adverse configurations of gut microbiota.

Metabolic biomarkers in irritable bowel syndrome diagnosis.

Irritable bowel syndrome (IBS) is a chronic gastrointestinal (GI) disorder characterized by altered bowel habits and abdominal discomfort during defecation. It significantly impacts life quality and work productivity for those affected. Global data suggests a slightly higher prevalence in females than in males. Today, unambiguous diagnosis of IBS remains challenging due to the absence of a specific biochemical, histopathological, or radiological test. Current diagnosis relies heavily on thorough symptom evaluation. Efforts by the Rome committees have established standardized diagnostic criteria (Rome I-IV), improving consistency and clinical applicability. Recent studies in this framework, seem to have successfully employed metabolomics techniques to identify distinct metabolite profiles in breath and stool samples of IBS patients, differentiating them from healthy controls and those with other functional GI disorders, such as inflammatory bowel disease (IBD). Building on this success, researchers are investigating the presence of similar metabolites in easily accessible biofluids such as urine, potentially offering a less invasive diagnostic approach. Accordingly, this review focuses on key metabolites specifically detected in IBS patients' biological specimens, with a focus on urinary metabolites, using various methods, particularly mass spectrometry (MS)-based techniques, including gas chromatography-MS (GC-MS), liquid chromatography-tandem MS (LC-MS/MS), and capillary electrophoresis-MS (CE-MS) metabolomics assays. These findings may make provision for a new set of non-invasive biomarkers for IBS diagnosis and management.