{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T00:04:04Z","timestamp":1791849844863,"version":"4.3.4"},"reference-count":36,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2019,6,25]],"date-time":"2019-06-25T00:00:00Z","timestamp":1561420800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100016942","name":"Ohio Department of Higher Education","doi-asserted-by":"publisher","award":["4241"],"award-info":[{"award-number":["4241"]}],"id":[{"id":"10.13039\/100016942","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>Inflammatory Bowel Disease (IBD) represents a collection of gastrointestinal disorders resulting from genetic and environmental factors. Microcystin-leucine arginine (MC-LR) is a toxin produced by cyanobacteria during algal blooms and demonstrates bioaccumulation in the intestinal tract following ingestion. Little is known about the impact of MC-LR ingestion in individuals with IBD. In this study, we sought to investigate MC-LR\u2019s effects in a dextran sulfate sodium (DSS)-induced colitis model. Mice were separated into four groups: (a) water only (control), (b) DSS followed by water (DSS), (c) water followed by MC-LR (MC-LR), and (d) DSS followed by MC-LR (DSS + MC-LR). DSS resulted in weight loss, splenomegaly, and severe colitis marked by transmural acute inflammation, ulceration, shortened colon length, and bloody stools. DSS + MC-LR mice experienced prolonged weight loss and bloody stools, increased ulceration of colonic mucosa, and shorter colon length as compared with DSS mice. DSS + MC-LR also resulted in greater increases in pro-inflammatory transcripts within colonic tissue (TNF-\u03b1, IL-1\u03b2, CD40, MCP-1) and the pro-fibrotic marker, PAI-1, as compared to DSS-only ingestion. These findings demonstrate that MC-LR exposure not only prolongs, but also worsens the severity of pre-existing colitis, strengthening evidence of MC-LR as an under-recognized environmental toxin in vulnerable populations, such as those with IBD.<\/jats:p>","DOI":"10.3390\/toxins11060371","type":"journal-article","created":{"date-parts":[[2019,6,25]],"date-time":"2019-06-25T10:52:31Z","timestamp":1561459951000},"page":"371","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["Exposure to the Harmful Algal Bloom (HAB) Toxin Microcystin-LR (MC-LR) Prolongs and Increases Severity of Dextran Sulfate Sodium (DSS)-Induced Colitis"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7423-0939","authenticated-orcid":false,"given":"Robin C.","family":"Su","sequence":"first","affiliation":[{"name":"Department of Medicine, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thomas M.","family":"Blomquist","sequence":"additional","affiliation":[{"name":"Department of Pathology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew L.","family":"Kleinhenz","sequence":"additional","affiliation":[{"name":"Department of Medicine, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1997-0977","authenticated-orcid":false,"given":"Fatimah K.","family":"Khalaf","sequence":"additional","affiliation":[{"name":"Department of Medicine, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Prabhatchandra","family":"Dube","sequence":"additional","affiliation":[{"name":"Department of Medicine, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6073-7432","authenticated-orcid":false,"given":"Apurva","family":"Lad","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology and Immunology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5892-1879","authenticated-orcid":false,"given":"Joshua D.","family":"Breidenbach","sequence":"additional","affiliation":[{"name":"Department of Medical Microbiology and Immunology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chrysan J.","family":"Mohammed","sequence":"additional","affiliation":[{"name":"Department of Medicine, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shungang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Medicine, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Caitlin E.","family":"Baum","sequence":"additional","affiliation":[{"name":"Department of Pathology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Deepak","family":"Malhotra","sequence":"additional","affiliation":[{"name":"Department of Medicine, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5265-0142","authenticated-orcid":false,"given":"David J.","family":"Kennedy","sequence":"additional","affiliation":[{"name":"Department of Medicine, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"},{"name":"Department of Medical Microbiology and Immunology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6919-6342","authenticated-orcid":false,"given":"Steven T.","family":"Haller","sequence":"additional","affiliation":[{"name":"Department of Medicine, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"},{"name":"Department of Medical Microbiology and Immunology, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,6,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"427","DOI":"10.1038\/nature06005","article-title":"Unravelling the pathogenesis of inflammatory bowel disease","volume":"448","author":"Xavier","year":"2007","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"720","DOI":"10.1038\/nrgastro.2015.150","article-title":"The global burden of IBD: from 2015 to 2025","volume":"12","author":"Kaplan","year":"2015","journal-title":"Nat. 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