Cellular and biochemical responses of the oyster Crassostrea gigas to controlled exposures to metals and Alexandrium minutum.

• Published in: Aquatic Toxicology
• Main Authors: Haberkorn, Hansy, Lambert, Christophe, Le Goïc, Nelly, Quéré, Claudie, Bruneau, Audrey, Riso, Ricardo, Auffret, Michel, Soudant, Philippe
• Other Authors: Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physiologie des Invertébrés Plouzané (LPI), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Institut Français de Recherche pour l'Exploitation de la Mer - Brest (IFREMER Centre de Bretagne), ANR-06-SEST-0023,MODECOPHY,Modélisation des mécanismes de contamination des coquillages par des phycotoxines(2006)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2014
• Subjects: Toxin accumulation; Physiological effects; Harmful algae; Metals; Oysters; ACL; [SDE]Environmental Sciences; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Pacific; Crassostrea gigas; Pacific oyster
• Online Access: https://hal.univ-brest.fr/hal-00948644; https://doi.org/10.1016/j.aquatox.2013.12.012

International audience Effects of simultaneous exposure of Pacific oyster, Crassostrea gigas, to both a harmful dinoflagellate that produces Paralytic Shellfish Toxins (PST), Alexandrium minutum, and cadmium (Cd) and copper (Cu), were assessed. Oysters were exposed to a mix of Cd-Cu with two different diets (i.e. A. minutum or Tisochrysis lutea) and compared to control oysters fed A. minutum or T. lutea, respectively, without metal addition. Metals and PST accumulations, digestive gland lipid composition, and cellular and biochemical hemolymph variables were measured after 4 days of exposure. Oysters exposed to Cd-Cu accumulated about thirty-six times less PSTs than oysters exposed to A. minutum alone. Exposure to Cd-Cu induced significant changes in neutral lipids (increase in diacylglycerol - DAG - and decrease in sterols) and phospholipids (decreases in phosphatidylcholine, phosphatidylethanolamine, cardiolipin and ceramide aminoethylphosphonate) of digestive gland suggesting that lipid metabolism disruptions and/or lipid peroxidation have occurred. Simultaneously, concentrations, percentages of dead cells and phenoloxidase activity of hemocytes increased in oysters exposed to metals while reactive oxygen species production of hemocytes decreased. Feeding on the harmful dinoflagellate A. minutum resulted in significant decreases in monoacylglycerol (MAG) and DAG and ether glycerides (EG), as well as significant increases in hemocyte concentration and phagocytic activity as compared to oysters fed T. lutea. Finally, the present study revealed that short-term, simultaneous exposure to Cd-Cu and A. minutum may induce antagonistic (i.e. hemocyte concentration and phagocytosis) or synergic (i.e. DAG content in digestive gland) effects upon cellular and tissular functions in oysters.