Neuroactive changes in the bowel of patients with IBS on low FODMAP diet: another piece of the puzzle

The publication of Rome IV saw the introduction of the term ‘disorder of gut brain interaction’ as a replacement for the previously used terminology ‘functional gastrointestinal (GI) disorder’ to describe GI conditions classified by symptoms related to any combination of motility disturbance, visceral hypersensitivity, dysregulated mucosal or immune function and gut microbiota, or altered central nervous system processing. A driving force for this change was a need to address the false perception that ‘functional’ disorders such as irritable bowel syndrome (IBS) are less real than ‘organic’ disorders such as inflammatory bowel disease (IBD) due to the absence of frank pathology in functional disorders which were often considered psychiatric or undefined in nature. While there is no doubt tissue from patients with IBS do not display histological or transcriptomic changes to the extent seen in IBD patients an ever-growing body of data has repeatedly shown marked functional effects of samples…

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Agosto 2023

Changes in signalling from faecal neuroactive metabolites following dietary modulation of IBS pain

Objective
Dietary therapies for irritable bowel syndrome (IBS) have received increasing interest but predicting which patients will benefit remains a challenge due to a lack of mechanistic insight. We recently found evidence of a role for the microbiota in dietary modulation of pain signalling in a humanised mouse model of IBS. This randomised cross-over study aimed to test the hypothesis that pain relief following reduced consumption of fermentable carbohydrates is the result of changes in luminal neuroactive metabolites.

Design
IBS (Rome IV) participants underwent four trial periods: two non-intervention periods, followed by a diet low (LFD) and high in fermentable carbohydrates for 3 weeks each. At the end of each period, participants completed questionnaires and provided stool. The effects of faecal supernatants (FS) collected before (IBS FS) and after a LFD (LFD FS) on nociceptive afferent neurons were assessed in mice using patch-clamp and ex vivo colonic afferent nerve recording techniques.

Results
Total IBS symptom severity score and abdominal pain were reduced by the LFD (N=25; p

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Agosto 2023

Role of the DOMINO diet application for managing IBS in primary care and beyond

We thank Rej et al for their interest in our DOMINO trial paper.1 2 In their letter, they point out that while the DOMINO application yields a statistically significant gain in responder rate over traditional medical therapy with otilonium bromide, the numerical difference is limited, as it amounts to only 10% at weeks 4 and 8. We want to point out that these margins are in the order of magnitude of the gain in response rate over placebo in recent trials with novel drugs for the treatment of Irritable Bowel Syndrome (IBS) that have seen regulatory approval.3–6 In addition, the attractiveness of the dietary approach in our view is not predominantly determined by superior efficacy compared with medical therapy. As the patient, through the diet smartphone application, achieves the ability to control symptoms using relatively simple dietary…

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Luglio 2023