Subcellular effects and lipid metabolism alterations in the gilthead seabream Sparus aurata fed on ovatoxins-contaminated mussels

• Published in: Chemosphere (Oxford) 2024-03, Vol.352, p.141413-141413, Article 141413
• Main Authors: Giuliani, Maria Elisa, Bacchiocchi, Simone, Accoroni, Stefano, Siracusa, Melania, Campacci, Debora, Notarstefano, Valentina, Mezzelani, Marica, Piersanti, Arianna, Totti, Cecilia, Benedetti, Maura, Regoli, Francesco, Gorbi, Stefania
• Format: Article
• Language: English
• Subjects: Animals; bioaccumulation; biosynthesis; diet; Dinoflagellida - genetics; Fatty Acids; fish; Humans; Lipid Metabolism; Lipids; liver; Marine Toxins - toxicity; microalgae; muscles; mussels; Mytilus; Mytilus galloprovincialis; Sea Bream; Seafood; seafoods; Sparus aurata; species; toxicity
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2024.141413

The marine microalgae Ostreopsis cf. ovata are a well-known producer of palytoxin (PlTXs) analogues, i.e. ovatoxins (OVTXs) among others, which arouse concern for animal and human health. Both in field and laboratory studies, presence of OVTXs, detected in species directly feeding on O. cf. ovata, was frequently correlated with impairment on organisms’ physiology, development and behaviour, while similar knowledge is still lacking for animals feeding on contaminated preys. In this study, transfer and toxicity of OVTXs were evaluated in an exposure experiment, in which gilthead seabream Sparus aurata was fed with bivalve mussel Mytilus galloprovincialis, contaminated by a toxic strain of O. cf. ovata. Mussels exposed to O. cf. ovata for 21 days accumulated meanly 188 ± 13 μg/kg OVTXs in the whole tissues. Seabreams fed with OVTX-contaminated mussels started to reject the food after 6 days of contaminated diet. Although no detectable levels of OVTXs were measured in muscle, liver, gills and gastro-intestinal tracts, the OVTX-enriched diet induced alterations of lipid metabolism in seabreams livers, displaying a decreased content of total lipid and fatty acid, together with overexpression of fatty acid biosynthetic genes, downregulation of β-oxidation genes and modulation of several genes related to lipid transport and regulation. Results from this study would suggest the hypothesis that OVTXs produced by O. cf. ovata may not be subject to bioaccumulation in fish fed on contaminated preys, being however responsible of significant biological effects, with important implications for human consumption of seafood products. [Display omitted] •Direct filtering on O. cf. ovata causes the accumulation of OVTXs in mussel.•Seabreams fed with OVTX-contaminated mussels started to reject the food after 6 days.•No detectable levels of OVTXs were measured in seabream fed with contaminated mussels.•OVTX-enriched diet induced alterations of lipid metabolism in seabreams liver.•Although not bioaccumulated, OVTXs could be responsible of biological effects in fish.