Toxicity of palytoxin, purified ovatoxin-a, ovatoxin-d and extracts of Ostreopsis cf. ovata on the Caco-2 intestinal barrier model

• Published in: Environmental toxicology and pharmacology 2022-08, Vol.94, p.103909-103909, Article 103909
• Main Authors: Gémin, Marin-Pierre, Lanceleur, Rachelle, Meslier, Lisa, Hervé, Fabienne, Réveillon, Damien, Amzil, Zouher, Ternon, Eva, Thomas, Olivier P., Fessard, Valérie
• Format: Article
• Language: English
• Subjects: Acrylamides; Caco-2 Cells; Dinoflagellida; Inflammation; Life Sciences; Marine Toxins; Ovatoxins; Palytoxin; Permeability; Purification; Toxicity; Toxicology
• ISSN: 1382-6689; 1872-7077
• DOI: 10.1016/j.etap.2022.103909

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. •Ovatoxin-a and -d have been successfully purified from Ostreopsis cf. ovata.•OVTX-a and -d were not toxic up to 20 ng/mL on Caco-2 differentiated cells.•OVTX-a and -d induced an inflammatory response through the release of IL-8.•OVTX-a but not OVTX-d affected the permeability of Caco-2 monolayers at 0.25 and 0.5 ng/mL.•OVTX-a and -d were less potent on differentiated Caco-2 cells than palytoxin.