{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T14:19:10Z","timestamp":1787667550288,"version":"build-2736575974"},"reference-count":55,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,3,31]],"date-time":"2021-03-31T00:00:00Z","timestamp":1617148800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Background: Oral iron supplementation causes gastrointestinal side effects. Short-term alterations in dietary iron exacerbate inflammation and alter the gut microbiota, in murine models of colitis. Patients typically take supplements for months. We investigated the impact of long-term changes in dietary iron on colitis and the microbiome in mice. Methods: We fed mice chow containing differing levels of iron, reflecting deficient (100 ppm), normal (200 ppm), and supplemented (400 ppm) intake for up to 9 weeks, both in absence and presence of dextran sodium sulphate (DSS)-induced chronic colitis. We also induced acute colitis in mice taking these diets for 8 weeks. Impact was assessed (i) clinically and histologically, and (ii) by sequencing the V4 region of 16S rRNA. Results: In mice with long-term changes, the iron-deficient diet was associated with greater weight loss and histological inflammation in the acute colitis model. Chronic colitis was not influenced by altering dietary iron however there was a change in the microbiome in DSS-treated mice consuming 100 ppm and 400 ppm iron diets, and control mice consuming the 400 ppm iron diet. Proteobacteria levels increased significantly, and Bacteroidetes levels decreased, in the 400 ppm iron DSS group at day-63 compared to baseline. Conclusions: Long-term dietary iron alterations affect gut microbiota signatures but do not exacerbate chronic colitis, however acute colitis is exacerbated by such dietary changes. More work is needed to understand the impact of iron supplementation on IBD. The change in the microbiome, in patients with colitis, may arise from the increased luminal iron and not simply from colitis.<\/jats:p>","DOI":"10.3390\/ijms22073646","type":"journal-article","created":{"date-parts":[[2021,3,31]],"date-time":"2021-03-31T21:37:03Z","timestamp":1617226623000},"page":"3646","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Long-Term Iron Deficiency and Dietary Iron Excess Exacerbate Acute Dextran Sodium Sulphate-Induced Colitis and Are Associated with Significant Dysbiosis"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6925-5018","authenticated-orcid":false,"given":"Awad","family":"Mahalhal","sequence":"first","affiliation":[{"name":"Department of Molecular and Cellular Cancer Medicine, Institute of Systems, Molecular and Integrated Biology, University of Liverpool, Liverpool L69 3GE, UK"},{"name":"Department of Anatomy and Histology, Faculty of Medicine, Benghazi University, Benghazi, Libya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5055-6408","authenticated-orcid":false,"given":"Michael D.","family":"Burkitt","sequence":"additional","affiliation":[{"name":"Division of Diabetes Endocrinology and Gastroenterology, Faculty of Biology Medicine and Health, University of Manchester, Manchester M13 9PL, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carrie A.","family":"Duckworth","sequence":"additional","affiliation":[{"name":"Molecular Physiology and Cell Signalling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3GE, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Georgina L.","family":"Hold","sequence":"additional","affiliation":[{"name":"Microbiome Research Centre, St George &amp; Sutherland Clinical School, Clinical Sciences (Pitney) Building, University of New South Wales Sydney, Kogarah, NSW 2217, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7407-012X","authenticated-orcid":false,"given":"Barry J.","family":"Campbell","sequence":"additional","affiliation":[{"name":"Department of Infection Biology &amp; Microbiomes, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool L69 3GE, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7971-3561","authenticated-orcid":false,"given":"David Mark","family":"Pritchard","sequence":"additional","affiliation":[{"name":"Department of Molecular and Cellular Cancer Medicine, Institute of Systems, Molecular and Integrated Biology, University of Liverpool, Liverpool L69 3GE, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4550-0239","authenticated-orcid":false,"given":"Chris S.","family":"Probert","sequence":"additional","affiliation":[{"name":"Department of Molecular and Cellular Cancer Medicine, Institute of Systems, Molecular and Integrated Biology, University of Liverpool, Liverpool L69 3GE, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"573","DOI":"10.1146\/annurev-immunol-030409-101225","article-title":"Inflammatory bowel disease","volume":"28","author":"Kaser","year":"2010","journal-title":"Annu. 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