Fiche publication
Date publication
mai 2018
Journal
Ecotoxicology and environmental safety
Auteurs
Membres identifiés du Cancéropôle Est :
Mr HAMMANN Philippe
Tous les auteurs :
Poirier I, Pallud M, Kuhn L, Hammann P, Demortière A, Jamali A, Chicher J, Caplat C, Gallon RK, Bertrand M
Lien Pubmed
Résumé
In the marine environment, benthic diatoms from estuarine and coastal sediments are among the first targets of nanoparticle pollution whose potential toxicity on marine organisms is still largely unknown. It is therefore relevant to improve our knowledge of interactions between these new pollutants and microalgae, the key players in the control of marine resources. In this study, the response of P. tricornutum to CdSe nanocrystals (CdSe NPs) of 5 nm (NP5) and 12 nm (NP12) in diameter was evaluated through microscopic, physiological, biochemical and proteomic approaches. NP5 and NP12 affected cell growth but oxygen production was only slightly decreased by NP5 after 1-d incubation time. In our experimental conditions, a high CdSe NP dissolution was observed during the first day of culture, leading to Cd bioaccumulation and oxidative stress, particularly with NP12. However, after a 7-day incubation time, proteomic analysis highlighted that P. tricornutum responded to CdSe NP toxicity by regulating numerous proteins involved in protection against oxidative stress, cellular redox homeostasis, Ca regulation and signalling, S-nitrosylation and S-glutathionylation processes and cell damage repair. These proteome changes allowed algae cells to regulate their intracellular ROS level in contaminated cultures. P. tricornutum was also capable to control its intracellular Cd concentration at a sufficiently low level to preserve its growth. To our knowledge, this is the first work allowing the identification of proteins differentially expressed by P. tricornutum subjected to NPs and thus the understanding of some molecular pathways involved in its cellular response to nanoparticles.
Mots clés
Marine microalgae, Nanoparticles, Oxidative stress, Physiological responses, Proteomics, Toxicity
Référence
Ecotoxicol. Environ. Saf.. 2018 May 15;152:78-90