Significance of metallothioneins in differential cadmium accumulation kinetics between two marine fish species

作者：Gaël Le Croizier, Camille CL Lacroix, Sébastien Artigaud, Stéphane Le Floch, Jean Raffray, Virginie Pénicaud, Valérie Coquillé, Julien Autier, Marie‐Laure Rouget, Nicolas Le Bayon, Raymond Laë, Luis Tito de Morais · 发表于：Environmental Pollution · 年份：2018 · DOI：10.1016/j.envpol.2018.01.002 · 被引用次数：79 · 研究领域：Environmental Toxicology and Ecotoxicology、Mercury impact and mitigation studies、Heavy Metal Exposure and Toxicity

Impacted marine environments lead to metal accumulation in edible marine fish, ultimately impairing human health. Nevertheless, metal accumulation is highly variable among marine fish species. In addition to ecological features, differences in bioaccumulation can be attributed to species-related physiological processes, which were investigated in two marine fish present in the Canary Current Large Marine Ecosystem (CCLME), where natural and anthropogenic metal exposure occurs. The European sea bass Dicentrarchus labrax and Senegalese sole Solea senegalensis were exposed for two months to two environmentally realistic dietary cadmium (Cd) doses before a depuration period. Organotropism (i.e., Cd repartition between organs) was studied in two storage compartments (the liver and muscle) and in an excretion vector (bile). To better understand the importance of physiological factors, the significance of hepatic metallothionein (MT) concentrations in accumulation and elimination kinetics in the two species was explored. Accumulation was faster in the sea bass muscle and liver, as inferred by earlier Cd increase and a higher accumulation rate. The elimination efficiency was also higher in the sea bass liver compared to sole, as highlighted by greater biliary excretion. In the liver, no induction of MT synthesis was attributed to metal exposure, challenging the relevance of using MT concentration as a biomarker of metal contamination. However, the basal MT pools were always greater i...