{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,29]],"date-time":"2026-06-29T21:50:56Z","timestamp":1782769856200,"version":"3.54.5"},"reference-count":55,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2023,9,23]],"date-time":"2023-09-23T00:00:00Z","timestamp":1695427200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003569","name":"Ministry of Food and Drug Safety","doi-asserted-by":"publisher","award":["20163MFDS641"],"award-info":[{"award-number":["20163MFDS641"]}],"id":[{"id":"10.13039\/501100003569","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003569","name":"Ministry of Food and Drug Safety","doi-asserted-by":"publisher","award":["2021M3H9A1038305"],"award-info":[{"award-number":["2021M3H9A1038305"]}],"id":[{"id":"10.13039\/501100003569","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Bio and Medical Technology Development Program of the National Research Foundation and the Korean government MIST","award":["20163MFDS641"],"award-info":[{"award-number":["20163MFDS641"]}]},{"name":"Bio and Medical Technology Development Program of the National Research Foundation and the Korean government MIST","award":["2021M3H9A1038305"],"award-info":[{"award-number":["2021M3H9A1038305"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>Okadaic acid (OA) and its analogues cause diarrhetic shellfish poisoning (DSP) in humans, and risk assessments of these toxins require toxicity equivalency factors (TEFs), which represent the relative toxicities of analogues. However, no human death by DSP toxin has been reported, and its current TEF value is based on acute lethality. To properly reflect the symptoms of DSP, such as diarrhea without death, the chronic toxicity of DSP toxins at sublethal doses should be considered. In this study, we obtained acute oral LD50 values for OA and dinophysistoxin-1 (DTX-1) (1069 and 897 \u03bcg\/kg, respectively) to set sublethal doses. Mice were treated with sublethal doses of OA and DTX-1 for 7 days. The mice lost body weight, and the disease activity index and intestinal crypt depths increased. Furthermore, these changes were more severe in OA-treated mice than in the DTX-1-treated mice. Strikingly, ascites was observed, and its severity was greater in mice treated with OA. Our findings suggest that OA is at least as toxic as DTX-1 after repeated oral administration at a low dose. This is the first study to compare repeated oral dosing of DSP toxins. Further sub-chronic and chronic studies are warranted to determine appropriate TEF values for DSP toxins.<\/jats:p>","DOI":"10.3390\/toxins15100587","type":"journal-article","created":{"date-parts":[[2023,9,24]],"date-time":"2023-09-24T10:48:31Z","timestamp":1695552511000},"page":"587","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Okadaic Acid Is at Least as Toxic as Dinophysistoxin-1 after Repeated Administration to Mice by Gavage"],"prefix":"10.3390","volume":"15","author":[{"given":"Se Yong","family":"Park","sequence":"first","affiliation":[{"name":"Department of Anatomy and Cell Biology, College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ju-Hee","family":"Kang","sequence":"additional","affiliation":[{"name":"College of Pharmacy, Gachon University, Incheon 21963, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyun Jin","family":"Jung","sequence":"additional","affiliation":[{"name":"College of Pharmacy, Gachon University, Incheon 21963, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jung Ho","family":"Hwang","sequence":"additional","affiliation":[{"name":"College of Pharmacy, Gachon University, Incheon 21963, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyang Sook","family":"Chun","sequence":"additional","affiliation":[{"name":"Food Toxicology Laboratory, School of Food Science and Technology, Chung-Ang University, Anseong 17546, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yeo Sung","family":"Yoon","sequence":"additional","affiliation":[{"name":"Department of Anatomy and Cell Biology, College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3678-2772","authenticated-orcid":false,"given":"Seung Hyun","family":"Oh","sequence":"additional","affiliation":[{"name":"College of Pharmacy, Gachon University, Incheon 21963, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"84","DOI":"10.1016\/j.toxicon.2016.03.021","article-title":"Accumulation, transformation and breakdown of DSP toxins from the toxic dinoflagellate Dinophysis acuta in blue mussels, Mytilus edulis","volume":"117","author":"Nielsen","year":"2016","journal-title":"Toxicon"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1363","DOI":"10.1021\/np0100486","article-title":"Isolation and structural determination of DTX-6, a new okadaic acid derivative","volume":"64","author":"Souto","year":"2001","journal-title":"J. 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