Mitochondrial activity, hemocyte parameters and lipid composition modulation by dietary conditioning in the Pacific oyster Crassostrea gigas.

• Published in: Journal of Comparative Physiology B
• Main Authors: Dudognon, Tony, Lambert, Christophe, Quere, Claudie, Auffret, Michel, Soudant, Philippe, Kraffe, Edouard
• 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 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)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physiologie des Invertébrés (LPI), Physiologie Fonctionnelle des Organismes Marins (PFOM), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2014
• Subjects: ACL; Crassostrea gigas; Diet; Fatty acid; Hemocytes; Mitochondria; Phospholipids; [SDE]Environmental Sciences; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Pacific; Pacific oyster
• Online Access: https://hal.univ-brest.fr/hal-00948647; https://doi.org/10.1007/s00360-013-0800-1

International audience Several parameters can affect membrane lipid composition in bivalves, including diet. Although two fatty acids (FA) 22:6n-3 and 20:5n-3 are essential membrane components, they are sparingly synthesized by bivalves and must be obtained from their diet. Here, effects of dietary modifications of membrane lipid composition were studied at both cellular and subcellular levels in the oyster Crassostrea gigas. To this end, we compared oysters fed two monoalgal diets that differed markedly in their FA composition and a mix of both. As expected, algae impacted phospholipids, in particular 22:6n-3 and 20:5n-3, reflecting differences of dietary microalgae FA composition. Meantime, total saturated FA, total monounsaturated FA, total polyunsaturated FA and total non-methylene-interrupted FA varied little and phospholipid class composition was only slightly affected by diets. Measures made in hemocytes indicated that only mitochondrial membrane potential was affected by diets. Total ROS production as well as mitochondrial superoxide production did not differ with diet. There was no difference in phosphorylating (state 3) and non-phosphorylating (state 4) rates of oxygen consumption rates or in cytochrome c oxidase activity of mitochondria isolated from gills between the three diets. Similarly, neither cytochromes a, b, c or c 1 content nor citrate synthase activities were changed, suggesting that number and morphology of mitochondria were not affected by dietary treatment. These results suggest that oysters could possess high homeostatic capabilities, at both cellular and subcellular levels, to minimize the effect of dietary FA and related membrane lipid FA modifications on mitochondrial functions. These capabilities could be a means to face variations in diet composition in their natural environment and to preserve important oyster physiological functions such as growth and reproduction.