IFREMER, Phycotoxins Laboratory, F-44311 Nantes, France.
ANSES, Fougères Laboratory, Toxicology of Contaminants Unit, French Agency for Food, Environmental and Occupational Health & Safety, Fougères 35306, France.
Environ Toxicol Pharmacol. 2022 Aug;94:103909. doi: 10.1016/j.etap.2022.103909. Epub 2022 Jun 17.
Human intoxications in the Mediterranean Sea have been linked to blooms of the dinoflagellate Ostreopsis cf. ovata, producer of palytoxin (PlTX)-like toxins called ovatoxins (OVTXs). Exposure routes include only inhalation and contact, although PlTX-poisoning by seafood has been described in tropical regions. To address the impact of OVTXs on the intestinal barrier, dinoflagellate extracts, purified OVTX-a and -d and PlTX were tested on differentiated Caco-2 cells. Viability, inflammatory response and barrier integrity were recorded after 24 h treatment. OVTX-a and -d were not cytotoxic up to 20 ng/mL but increased IL-8 release, although to a lesser extent compared to PlTX. While PlTX and OVTX-a (at 0.5 and 5 ng/mL respectively) affected intestinal barrier integrity, OVTX-d up to 5 ng/mL did not. Overall, OVTX-d was shown to be less toxic than OVTX-a and PlTX. Therefore, oral exposure to OVTX-a and -d could provoked lower acute toxicity than PlTX.
地中海海域的人类中毒事件与菱形藻属 ovata 的大量繁殖有关，该藻产生类似于 palytoxin（PLTX）的毒素，称为 ovatoxins（OVTXs）。暴露途径仅包括吸入和接触，尽管在热带地区已描述过通过海鲜摄入 PLTX 中毒的情况。为了研究 OVTXs 对肠道屏障的影响，对分化的 Caco-2 细胞进行了藻类提取物、纯化的 OVTX-a 和 -d 以及 PLTX 的测试。处理 24 小时后，记录细胞活力、炎症反应和屏障完整性。OVTX-a 和 -d 的细胞毒性在 20 ng/mL 以下，但会增加 IL-8 的释放，尽管与 PLTX 相比，其程度较小。虽然 PLTX 和 OVTX-a（分别为 0.5 和 5 ng/mL）会影响肠道屏障的完整性，但 5 ng/mL 以下的 OVTX-d 则不会。总体而言，OVTX-d 的毒性小于 OVTX-a 和 PLTX。因此，口服暴露于 OVTX-a 和 -d 可能比 PLTX 引起的急性毒性更低。
