Microbiota Therapy in Inflammatory Bowel Disease.

Background: In both Crohn's disease (CD) and ulcerative colitis (UC), the two major forms of inflammatory bowel disease (IBD) the immune reaction is - at least partially - directed against components of the luminal microbiota of the gut. These immune responses as well as other factors contribute to a phenomenon frequently described as "dysbiosis" meaning an alteration of the composition of the colonic microbiota. To improve the dysbiosis and to restore the normal composition of the colonic microbiota, fecal microbiota transplantation (FMT) has been tested as a therapeutic option to induce and maintain remission in IBD patients. Summary: This review will first discuss changes in the composition of the intestinal microbiota found in IBD patients and second the therapeutic potential of microbiological interventions for the treatment of these patients. FMT has been studied in several clinical trials in both, CD and UC. Reported results and subsequent meta-analyses indicate that FMT may be effective to induce remission in UC. However, the optimal route of FMT, the necessary number of administrations and the question whether life bacteria of freshly prepared stool is more effective than frozen are still unclear. Concepts associated with an optimization of FMT such as the "super donor concept" or the "consortia-approach" will be discussed to illustrate open questions and difficulties associated with microbiota therapy in IBD. Key Messages: The microbiota composition in IBD patients shows significant alterations compared to healthy individuals termed as "dysbiosis". FMT and other therapeutic approaches to modify the microbiota composition have been studied in clinical trials in recent years. Efficacy has been shown in UC; however, many questions with respect to the optimization of microbiota therapy remain to be answered.

The proton-sensing receptors TDAG8 and GPR4 are differentially expressed in human and mouse oligodendrocytes: Exploring their role in neuroinflammation and multiple sclerosis.

Acidosis is one of the hallmarks of demyelinating central nervous system (CNS) lesions in multiple sclerosis (MS). The response to acidic pH is primarily mediated by a family of G protein-coupled proton-sensing receptors: OGR1, GPR4 and TDAG8. These receptors are inactive at alkaline pH, reaching maximal activation at acidic pH. Genome-wide association studies have identified a locus within the TDAG8 gene associated with several autoimmune diseases, including MS. Accordingly, we here found that expression of TDAG8, as opposed to GPR4 or OGR1, is upregulated in MS plaques. This led us to investigate the expression of TDAG8 in oligodendrocytes using mouse and human in vitro and in vivo models. We observed significant upregulation of TDAG8 in human MO3.13 oligodendrocytes during maturation and in response to acidic conditions. However, its deficiency did not impact normal myelination in the mouse CNS, and its expression remained unaltered under demyelinating conditions in mouse organotypic cerebellar slices. Notably, our data revealed no expression of TDAG8 in primary mouse oligodendrocyte progenitor cells (OPCs), in contrast to its expression in primary human OPCs. Our investigations have revealed substantial species differences in the expression of proton-sensing receptors in oligodendrocytes, highlighting the limitations of the employed experimental models in fully elucidating the role of TDAG8 in myelination and oligodendrocyte biology. Consequently, the study does not furnish robust evidence for the role of TDAG8 in such processes. Nonetheless, our findings tentatively point towards a potential association between TDAG8 and myelination processes in humans, hinting at a potential link between TDAG8 and the pathophysiology of MS and warrants further research.

Role of pH-sensing receptors in colitis.

Low pH in the gut is associated with severe inflammation, fibrosis, and colorectal cancer (CRC) and is a hallmark of active inflammatory bowel disease (IBD). Subsequently, pH-sensing mechanisms are of interest for the understanding of IBD pathophysiology. Tissue hypoxia and acidosis-two contributing factors to disease pathophysiology-are linked to IBD, and understanding their interplay is highly relevant for the development of new therapeutic options. One member of the proton-sensing G protein-coupled receptor (GPCR) family, GPR65 (T-cell death-associated gene 8, TDAG8), was identified as a susceptibility gene for IBD in a large genome-wide association study. In response to acidic extracellular pH, GPR65 induces an anti-inflammatory response, whereas the two other proton-sensing receptors, GPR4 and GPR68 (ovarian cancer G protein-coupled receptor 1, OGR1), mediate pro-inflammatory responses. Here, we review the current knowledge on the role of these proton-sensing receptors in IBD and IBD-associated fibrosis and cancer, as well as colitis-associated cancer (CAC). We also describe emerging small molecule modulators of these receptors as therapeutic opportunities for the treatment of IBD.

Development of non-alcoholic steatohepatitis is associated with gut microbiota but not with oxysterol enzymes CH25H, EBI2, or CYP7B1 in mice.

Liver steatosis is the most frequent liver disorder and its advanced stage, non-alcoholic steatohepatitis (NASH), will soon become the main reason for liver fibrosis and cirrhosis. The "multiple hits hypothesis" suggests that progression from simple steatosis to NASH is triggered by multiple factors including the gut microbiota composition. The Epstein Barr virus induced gene 2 (EBI2) is a receptor for the oxysterol 7a, 25-dihydroxycholesterol synthesized by the enzymes CH25H and CYP7B1. EBI2 and its ligand control activation of immune cells in secondary lymphoid organs and the gut. Here we show a concurrent study of the microbial dysregulation and perturbation of the EBI2 axis in a mice model of NASH.We used mice with wildtype, or littermates with CH25H-/-, EBI2-/-, or CYP7B1-/- genotypes fed with a high-fat diet (HFD) containing high amounts of fat, cholesterol, and fructose for 20 weeks to induce liver steatosis and NASH. Fecal and small intestinal microbiota samples were collected, and microbiota signatures were compared according to genotype and NASH disease state.We found pronounced differences in microbiota composition of mice with HFD developing NASH compared to mice did not developing NASH. In mice with NASH, we identified significantly increased 33 taxa mainly belonging to the Clostridiales order and/ or the family, and significantly decreased 17 taxa. Using an Elastic Net algorithm, we suggest a microbiota signature that predicts NASH in animals with a HFD from the microbiota composition with moderate accuracy (area under the receiver operator characteristics curve = 0.64). In contrast, no microbiota differences regarding the studied genotypes (wildtype vs knock-out CH25H-/-, EBI2-/-, or CYP7B1-/-) were observed.In conclusion, our data confirm previous studies identifying the intestinal microbiota composition as a relevant marker for NASH pathogenesis. Further, no link of the EBI2 - oxysterol axis to the intestinal microbiota was detectable in the current study.

Specific antibiotics increases the risk of flare-ups in patients with inflammatory bowel disease - results from a Danish nationwide population-based nested case-control study.

INTRODUCTION: IBD patients have a relapsing-remitting disease course, and amongst environmental factors that aggravate the disease course, common drugs aside from NSAIDs are not studied in detail. While the microbiome is considered to play a significant role on the disease course the impact of antibiotics is poorly understood. This study investigated the potential impact of different classes of antibiotics on course of disease in IBD using the Danish National Patient Registry. METHODS: Danish IBD patients were studied using two nested case-control cohorts exploring associations between antibiotic types and IBD flare-ups, defined as IBD-related hospitalizations and/or high-dose systemic steroid exposure. Multivariate logistic regression and eXtreme Gradient Boosted decision tree (GBDT) machine learning methods evaluated antibiotic risks. RESULTS: Two cohorts with 15,636 and 5,178 patients were analysed for risk of hospitalisation and course of steroids, respectively.The risk of a flare-up was significantly increased with antecedent exposure to quinolones (ATC:J01M. OR:3.04-3.82), antimycotics (ATC:J02A. OR:1.50-2.30), agents against amoebiasis and protozoal infections (ATC:P01A. OR: 1.95-3.18), intestinal anti-infectives (ATC:A07A. OR:2.09-2.32) and beta-lactam antibiotics (ATC:J01C. OR:1.36).The GBDT models achieved an AUC between 0.71-0.85 for predicting flare-ups, with the same above-mentioned antibiotics being in the 10 most important variables. CONCLUSION: We found distinctive antibiotics to be significantly associated with an increased risk of IBD flare-ups. Our findings are corroborated by our GBDT machine learning models. Healthcare providers should be aware about the deleterious potential of specific antibiotic groups in patients with IBD only using these agents in a restrictive manner or preferentially consider alternative antibiotic groups.

Withdrawal and Re-treatment with Filgotinib in Ulcerative Colitis: Post Hoc Analyses of the Phase 2b/3 SELECTION and SELECTIONLTE Studies.

BACKGROUND AND AIMS: Maintenance treatment for ulcerative colitis may be discontinued for multiple reasons. This post hoc analysis assessed the efficacy and safety of re-treatment with filgotinib, an oral, once-daily, Janus kinase 1 preferential inhibitor, in the phase 2b/3 SELECTION trial and its long-term extension [LTE] study in ulcerative colitis. METHODS: Partial Mayo Clinic Score [pMCS] response and remission were evaluated in patients who received induction with filgotinib 200 mg [FIL200] or 100 mg [FIL100], were randomized to treatment withdrawal [placebo] during maintenance, and following disease worsening, were re-treated with open-label FIL200 in the LTE study. Factors were evaluated for association with pMCS remission at LTE week 12, and safety outcomes were reported. RESULTS: Analyses included 86 patients [FIL200: n = 51; FIL100: n = 35]. Median time to disease worsening following treatment withdrawal was 15.1 weeks (95% confidence interval [CI]: 9.1-18.7) for FIL200-induced patients and 9.6 weeks [95% CI: 6.3-12.0] for FIL100-induced patients. Three-quarters [75%] of patients achieved a pMCS response within 4-5 weeks of re-treatment in both groups. At LTE week 48, pMCS remission was achieved by 45.1% and 51.4% of FIL200- and FIL100-induced patients, respectively. Factors independently associated with restoring efficacy included no concomitant use of corticosteroids at induction baseline, and high albumin levels, pMCS remission, and endoscopic score at maintenance baseline. No new safety signals were reported among re-treated patients. CONCLUSIONS: In induction responders, re-treatment with FIL200 following temporary withdrawal from therapy restores response and/or remission in the majority of patients within 12 weeks. Re-treatment is well-tolerated. ClinicalTrials.gov identifiers: NCT02914522, NCT02914535.

Childlessness in Patients with Inflammatory Bowel Disease - Data from the Prospective Multi-center Swiss IBD Cohort Study.

BACKGROUND AND AIMS: Childlessness and infertility represent a frequent and important issue in inflammatory bowel disease (IBD) patients. Nevertheless, until now epidemiological data remains scarce. Therefore, main objectives of this study were to evaluate the rate of childlessness and the cumulative probability of reproduction in female and male IBD patients within the Swiss Inflammatory Bowel Disease Cohort Study (SIBDCS), a large prospective multicenter nationwide cohort. METHODS: Prospectively collected data of SIBDCS was used, comprising more than 3,300 patients with Crohn's disease (CD) and ulcerative colitis (UC). We analyzed the following groups of patients: 1) female IBD patients aged ≥40 years and diagnosed before age of 30 years with at least one follow-up, 2) female IBD patients who reported actively trying to conceive, with IBD diagnosed <35 years and with age at enrolment <45 years (longitudinal observation), with at least one follow-up, and 3) childless males who actively tried to conceive. RESULTS: A total of 1,412 female patients from the SIBDCS [843 CD, 539 UC, 30 indeterminate colitis (IC)] with available data were included in our analyses. Out of those 184 females (70.1% CD and 29.9 % UC) were aged ≥ 40 years and have been diagnosed with IBD before the age of 30 years. Among these, 184 women 32.1% were childless. The portion of childless females (36.4%) was significantly higher in CD vs. UC (36.4% vs. 21.8%; p=0.026), equaling a relative risk of childlessness of 1.7 in CD vs. UC. and higher than in the Swiss general population (21%). The mean number of children per female patient was 1.32 (median 1, min 0, max 6), per female with CD 1.12 (median 1, min 0, max 4), per female with UC/IC 1.78 (median 2, min 0, max 6; P=0.001). The longitudinal analysis of female IBD patients trying to conceive revealed that one out of two women neither were pregnant nor had born a child five years after first trying to conceive. CONCLUSIONS: The rate of childlessness in females with CD is higher compared to the general Swiss population, whereas it is similar in women with UC. Moreover, the mean number of children is lower in CD than in UC. Females with CD remain more often childless compared to their UC counterparts. Although the exact underlying mechanisms are largely unknown, this discrepancy should alert healthcare professionals treating CD patients to actively address this topic.

Concomitant 5-aminosalicylic acid treatment does not affect 6-thioguanine nucleotide levels in patients with inflammatory bowel disease on thiopurines.

Background: There are conflicting data as to whether co-treatment with 5-aminosalicylic acid (5-ASA) in patients with inflammatory bowel disease (IBD) under azathioprine (AZA) or 6-mercaptopurine (6-MP) therapy may influence 6-thioguanine nucleotide (6-TGN) concentrations, and whether this combination puts patients at risk of side-effects. The aim of the study was to determine 6-TGN levels in patients treated with AZA/6-MP, either alone or in combination with 5-ASA. Methods: Available blood samples from patients treated with AZA or 6-MP were retrieved from the Swiss IBD Cohort Study (SIBDCS). The eligible individuals were divided into 2 groups: those with vs. without 5-ASA co-medication. Levels of 6-TGN and 6-methylmercaptopurine ribonucleotides (6-MMPR) were determined and compared. Potential confounders were compared between the groups, and also evaluated as potential predictors for a multivariate regression model. Results: Of the 110 patients enrolled in this analysis, 40 received concomitant 5-ASA at the time of blood sampling. The median 6-TGN levels in patients with vs. those without 5-ASA co-treatment were 261 and 257 pmol/8×108 erythrocytes, respectively (P=0.97). Likewise, there were no significant differences in 6-MMPR levels (P=0.79). Through multivariate analysis, 6-TGN levels were found to be significantly higher in non-smokers, patients without prior surgery, and those without signs of stress-hyperarousal. Conclusions: Blood concentrations of 6-TGN and 6-MMPR did not differ between patients with vs. those without 5-ASA co-treatment. Our data warrant neither more frequent lab monitoring nor dose adaptation of AZA in patients receiving concomitant 5-ASA treatment.

Impact of Concomitant Thiopurine on the Efficacy and Safety of Filgotinib in Patients with Ulcerative Colitis: Post hoc Analysis of the Phase 2b/3 SELECTION Study.

BACKGROUND AND AIMS: SELECTION is the first study to assess the impact of concomitant thiopurine and other immunomodulator [IM] use on the efficacy and safety of a Janus kinase inhibitor, filgotinib, in patients with ulcerative colitis. METHODS: Data from the phase 2b/3 SELECTION study were used for this post hoc analysis. Patients were randomized [2:2:1] to two induction studies [biologic-naive, biologic-experienced] to filgotinib 200 mg, 100 mg, or placebo. At week 10, patients receiving filgotinib were re-randomized [2:1] to continue filgotinib or switch to placebo until week 58 [maintenance]. Outcomes were compared between subgroups with and without concomitant IM use. RESULTS: At week 10, a similar proportion of patients in +IM and -IM groups treated with filgotinib 200 mg achieved Mayo Clinic Score [MCS] response [biologic-naive: 65.8% vs 66.9%; biologic-experienced: 61.3% vs 50.5%] and clinical remission [biologic-naive: 26.0% vs 26.2%; biologic-experienced: 11.3% vs 11.5%]. At week 58, a similar proportion of patients in +IM and -IM groups treated with filgotinib 200 mg achieved MCS response [biologic-naive: 74.2% vs 75.0%; biologic-experienced: 45.5% vs 61.4%] and clinical remission [biologic-naive: 51.6% vs 47.4%; biologic-experienced: 22.7% vs 24.3%]. The probability of protocol-specified disease worsening during the maintenance study in patients treated with filgotinib 200 mg did not differ between +IM and -IM groups [p = 0.6700]. No differences were observed in the incidences of adverse events between +IM and -IM groups in induction/maintenance studies. CONCLUSIONS: The efficacy and safety profiles of filgotinib treatment in SELECTION did not differ with or without concomitant IM use.

[Microbiome: from pathophysiology to clinical application?] / Mikrobiom: von der Pathophysiologie in die Klinik?

The "microbiome" or the intestinal microbiota is currently in the focus of scientific interest. The number of publications on the topic of the microbiome is increasing every year. In particular, the role of the microbiome in the pathophysiology of various diseases has been studied. Currently it is impossible to have an overview on all new developments with over 25.000 publication in the field per year. However, some key news stand out from this large number of publications. The first microbiota compounds for the therapy of Clostridioides difficile colitis were approved by the FDA last year or are about to be approved. This means that, for the first time, standardized microbiome products are available in addition to fecal microbiota transplantation (FMT) and are finding their way into everyday clinical practice.

OGR1 (GPR68) and TDAG8 (GPR65) Have Antagonistic Effects in Models of Colonic Inflammation.

G-protein-coupled receptors (GPRs), including pro-inflammatory ovarian cancer GPR1 (OGR1/GPR68) and anti-inflammatory T cell death-associated gene 8 (TDAG8/GPR65), are involved in pH sensing and linked to inflammatory bowel disease (IBD). OGR1 and TDAG8 show opposite effects. To determine which effect is predominant or physiologically more relevant, we deleted both receptors in models of intestinal inflammation. Combined Ogr1 and Tdag8 deficiency was assessed in spontaneous and acute murine colitis models. Disease severity was assessed using clinical scores. Colon samples were analyzed using quantitative polymerase chain reaction (qPCR) and flow cytometry (FACS). In acute colitis, Ogr1-deficient mice showed significantly decreased clinical scores compared with wildtype (WT) mice, while Tdag8-deficient mice and double knockout (KO) mice presented similar scores to WT. In Il-10-spontaneous colitis, Ogr1-deficient mice presented significantly decreased, and Tdag8-deficient mice had increased inflammation. In the Il10-/- × Ogr1-/- × Tdag8-/- triple KO mice, inflammation was significantly decreased compared with Tdag8-/-. Absence of Ogr1 reduced pro-inflammatory cytokines in Tdag8-deficient mice. Tdag8-/- had significantly more IFNγ+ T-lymphocytes and IL-23 T-helper cells in the colon compared with WT. The absence of OGR1 significantly alleviates the intestinal damage mediated by the lack of functional TDAG8. Both OGR1 and TDAG8 represent potential new targets for therapeutic intervention.

Crosstalk within peripheral blood mononuclear cells mediates anti-inflammatory effects of n-3 PUFA-rich lipid emulsions in parenteral nutrition.

BACKGROUND AND AIMS: Parenteral nutrition (PN) rich in n-6 and n-3 long-chain fatty acids is used in clinical practice for nourishing patients who are unable to receive adequate nutrition through their digestive systems. In this study, we compare the effect on inflammation of the commonly used lipid emulsions Omegaven (n-3-rich) and Intralipid (n-6-rich) in human peripheral blood mononuclear cells (PBMCs). METHODS: PBMCs were treated with different doses of n-3-rich Omegaven and n-6-rich Intralipid and the immune cells were characterized by flow cytometry. RESULTS: We show that incubation of PBMCs with n-3-rich Omegaven leads to an increase in expression of CD1d and CD86 in CD14+monocytes. At the same time, an increased number of NKT cells expressing cytotoxic T cell antigen 4 is observed, suggesting immunological synapse formation. Both CD14+monocytes and NKT cells showed an increase in IL-10 production and a reduction in the pro-inflammatory cytokines IFN-γ, TNF-α, and IL-4, which led to an increase in the number of FOXP3+T regulatory cells. In addition, we show that n-3-rich Omegaven reduces the expression of TNFα, IFNγ and IL-4 in CD4+T and CD8+T cells independent of the presented interaction between CD14+monocytes and NKT cells. The described mechanism of n-3 rich lipid emulsions was confirmed in PBMCs from patients with inflammatory bowel disease but not in colorectal cancer patients which seem to lack the interaction between CD14+monocytes and NKT cells. CONCLUSIONS: These results show a mechanism for the beneficial effect of the n-3-rich Omegaven in patients with inflammatory conditions but questions its use in patients with cancer. Hence, our results may assist in choosing the best lipid emulsion for patients who require PN.

Integrated safety analysis of filgotinib for ulcerative colitis: Results from SELECTION and SELECTIONLTE.

BACKGROUND: Filgotinib 200 mg (FIL200) is an approved treatment for adults with moderately to severely active ulcerative colitis (UC). AIM: To report integrated safety data from the phase 2b/3 SELECTION study (NCT02914522) and its ongoing long-term extension study SELECTIONLTE (NCT02914535). METHODS: Safety outcomes were analysed in adults with moderately to severely active UC who received FIL200, filgotinib 100 mg (FIL100) or placebo once daily throughout the 11-week SELECTION induction study, the 47-week SELECTION maintenance study (if applicable) and SELECTIONLTE (if applicable). Exposure-adjusted incidence rates (EAIRs) per 100 censored patient-years of exposure with 95% confidence intervals were reported for treatment-emergent adverse events (AEs). Certain AE data were presented in subgroups, including age and prior biologic exposure status. RESULTS: This interim analysis included 1348 patients representing 3326.2 patient-years of exposure. Baseline characteristics of patients entering SELECTION were similar across treatment groups. EAIRs for serious infection, thromboembolic events and major adverse cardiovascular events (MACE) were consistently low across treatment groups. Most patients with MACE had cardiovascular risk factors. The EAIR for herpes zoster was numerically higher for FIL200 than for placebo. Infection incidences were numerically higher in biologic-experienced than biologic-naive patients. Higher incidences of certain AEs in patients 65 years of age or older were as expected. Four deaths occurred, including three cardiovascular deaths, none of which was considered related to filgotinib. CONCLUSION: FIL200 and FIL100 were well tolerated with no unexpected safety signals in patients with moderately to severely active UC, regardless of previous biologic exposure or age. GOV IDENTIFIERS (NCT NUMBERS): NCT02914522, NCT02914535.

Because I'm happy - positive affect and its predictive value for future disease activity in patients with inflammatory bowel diseases: a retrospective cohort study.

Background: While the detrimental impact of negative emotions on the clinical course of inflammatory bowel disease (IBD) and quality of life has been extensively investigated, evidence for a potential impact of positive emotions is scarce. Objectives: We aim to analyse contributing factors of positive affect and their predictive value for disease course in IBD patients. Design: In this retrospective cohort study, epidemiological, psychosocial and IBD disease characteristics of Swiss IBD cohort study patients were analysed longitudinally. Methods: Epidemiological, psychosocial and disease characteristics were extracted from the database of the Swiss IBD cohort study. Participants' positive emotions were assessed cross-sectionally with the seven-item Marburg questionnaire (range 1-6) addressing positive affect in different aspects of daily life. Predictors of positive emotions were identified by linear regression. The quantitative longitudinal impact of positive emotions on the further disease course was analysed using a multivariable Cox proportional hazards model. Results: Among 702 IBD patients, those reporting more positive emotions were found to have significantly less intense medical treatment, less pain and fewer depressive symptoms (p < 0.05). A higher percentage of variability in positive emotions was explained by pain (36%) and depressive symptoms (13%) than by epidemiological characteristics (0.3%), or characteristics of IBD and its treatment (2.4%). Patients with higher levels of positive emotions (score > 3.5) experienced longer flare-free survival, also after adjusting for confounders (adjusted hazard ratio: 0.39, p < 0.05). Conclusions: The absence of pain and depressive symptoms were the strongest drivers for high positive affect. Higher scores of positive affect were associated with longer disease-free survival in IBD patients.

The Efficacy of a Diet Low in Fermentable Oligo-, Di-, Monosaccharides, and Polyols in Irritable Bowel Syndrome Compared to Its "Real-world" Effectiveness: Protocol for a Systematic Review.

BACKGROUND: Irritable bowel syndrome (IBS) is associated with various gastrointestinal and nongastrointestinal symptoms and reduced quality of life. A diet low in fermentable oligo-, di-, monosaccharides, and polyols (FODMAPs) is one therapeutic option for IBS. Although the efficacy of the low FODMAP diet has been reported in several systematic reviews, the efficacy-effectiveness gap of the low FODMAP diet has not yet been assessed. OBJECTIVE: This systematic review aims to compare the efficacy of the low FODMAP diet from efficacy randomized controlled trials (RCTs) with the effectiveness of studies conducted in "real-world" settings. METHODS: RCTs, prospective and retrospective cohort studies, and retrospective audits assessing the low FODMAP diet in adults with IBS will be searched in 4 databases: Embase, MEDLINE, CENTRAL, and CINAHL. Two independent reviewers will perform study selection, data extraction, and risk of bias assessment and assess selected quality aspects from the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) protocol. Outcomes assessed are stool frequency, stool consistency, abdominal pain, overall symptom scores, adequate symptom relief, IBS-specific quality of life, and diet adherence. Data will be summarized with forest plots without summary statistics, tables, and narrative descriptions. RESULTS: The search, title and abstract screening, and full-text screening were completed in March 2021, and an updated search was done in May 2022. As of May 2023, data analysis is almost finished, and manuscript writing is in progress. Submission of the manuscript is expected by July 2023. CONCLUSIONS: The findings of this systematic review will compare the efficacy of the low FODMAP diet for IBS found in RCTs to the diet's real-world effectiveness. TRIAL REGISTRATION: PROSPERO CRD42021278952; https://tinyurl.com/32jk43ev. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/41399.

Association between Helicobacter pylori Infection and Nasal Polyps: A Systematic Review and Meta-Analysis.

BACKGROUND: Helicobacter pylori (H. pylori) has definite or possible associations with multiple local and distant manifestations. H. pylori has been isolated from multiple sites throughout the body, including the nose. Clinical non-randomized studies with H. pylori report discrepant data regarding the association between H. pylori infection and nasal polyps. The aim of this first systematic review and meta-analysis was the assessment of the strength of the association between H. pylori infection and incidence of nasal polyps. METHODS: We performed an electronic search in the three major medical databases, namely PubMed, EMBASE and Cochrane, to extract and analyze data as per PRISMA guidelines. RESULTS: Out of 57 articles, 12 studies were graded as good quality for analysis. Male-to-female ratio was 2:1, and age ranged between 17-78 years. The cumulative pooled rate of H. pylori infection in the nasal polyp group was 32.3% (controls 17.8%). The comparison between the two groups revealed a more significant incidence of H. pylori infection among the nasal polyp group (OR 4.12), though with high heterogeneity I2 = 66%. Subgroup analysis demonstrated that in European studies, the prevalence of H. pylori infection among the nasal polyp group was significantly higher than in controls, yielding null heterogeneity. Subgroup analysis based on immunohistochemistry resulted in null heterogeneity with preserving a statistically significant difference in H. pylori infection prevalence between the groups. CONCLUSION: The present study revealed a positive association between H. pylori infection and nasal polyps.

Temperature-triggered in situ forming lipid mesophase gel for local treatment of ulcerative colitis.

Ulcerative colitis is a chronic inflammatory bowel disease that strongly affects patient quality of life. Side effects of current therapies necessitate new treatment strategies that maximise the drug concentration at the site of inflammation, while minimizing systemic exposure. Capitalizing on the biocompatible and biodegradable structure of lipid mesophases, we present a temperature-triggered in situ forming lipid gel for topical treatment of colitis. We show that the gel is versatile and can host and release drugs of different polarities, including tofacitinib and tacrolimus, in a sustained manner. Further, we demonstrate its adherence to the colonic wall for at least 6 h, thus preventing leakage and improving drug bioavailability. Importantly, we find that loading known colitis treatment drugs into the temperature-triggered gel improves animal health in two mouse models of acute colitis. Overall, our temperature-triggered gel may prove beneficial in ameliorating colitis and decreasing adverse effects associated with systemic application of immunosuppressive treatments.

Tigecycline reduces tumorigenesis in colorectal cancer via inhibition of cell proliferation and modulation of immune response.

BACKGROUND: and Purpose: Colorectal cancer (CRC) is one of the cancers with the highest incidence in which APC gene mutations occur in almost 80% of patients. This mutation leads to ß-catenin aberrant accumulation and an uncontrolled proliferation. Apoptosis evasion, changes in the immune response and microbiota composition are also events that arise in CRC. Tetracyclines are drugs with proven antibiotic and immunomodulatory properties that have shown cytotoxic activity against different tumor cell lines. EXPERIMENTAL APPROACH: The effect of tigecycline was evaluated in vitro in HCT116 cells and in vivo in a colitis-associated colorectal cancer (CAC) murine model. 5-fluorouracil was assayed as positive control in both studies. KEY RESULTS: Tigecycline showed an antiproliferative activity targeting the Wnt/ß-catenin pathway and downregulating STAT3. Moreover, tigecycline induced apoptosis through extrinsic, intrinsic and endoplasmic reticulum pathways converging on an increase of CASP7 levels. Furthermore, tigecycline modulated the immune response in CAC, reducing the cancer-associated inflammation through downregulation of cytokines expression. Additionally, tigecycline favored the cytotoxic activity of cytotoxic T lymphocytes (CTLs), one of the main immune defenses against tumor cells. Lastly, the antibiotic reestablished the gut dysbiosis in CAC mice increasing the abundance of bacterial genera and species, such as Akkermansia and Parabacteroides distasonis, that act as protectors against tumor development. These findings resulted in a reduction of the number of tumors and an amelioration of the tumorigenesis process in CAC. CONCLUSION AND IMPLICATIONS: Tigecycline exerts a beneficial effect against CRC supporting the use of this antibiotic for the treatment of this disease.

Lifestyle factors associated with inflammatory bowel disease: data from the Swiss IBD cohort study.

BACKGROUND: Various environmental risk factors have been associated with the pathogenesis of inflammatory bowel disease. In this study we aimed to identify lifestyle factors that affect the onset of Crohn's disease and ulcerative colitis. METHODS: 2294 patients from the Swiss IBD Cohort Study received a questionnaire regarding physical activity, nutritional habits and status of weight. In addition, a control group was formed comprising patients' childhood friends, who grew up in a similar environment. RESULTS: Overall, 1111 questionnaires were returned (response rate: 48.4%). Significantly more patients with inflammatory bowel disease reported no regular practice of sport during childhood and beginning of adulthood compared to the control group (p = 0.0001). No association between intake of refined sugar and onset of inflammatory bowel disease was observed. More patients with Crohn's disease compared to ulcerative colitis and controls suffered from overweight during childhood (12.8% vs. 7.7% and 9.7%, respectively; p = 0.027). CONCLUSIONS: Our study underlines the relevance of environmental factors in the development of inflammatory bowel disease. Our results imply a protective effect of physical activity regarding the onset of inflammatory bowel disease.