Karray Sahar, Marchand Justine, Moreau Brigitte, Tastard Emmanuelle, Thiriet-Rupert Stanislas, Geffard Alain, Delahaut Laurence, Denis Françoise, Hamza-Chaffai Amel, Chénais Benoît
Université du Maine - Le Mans, EA 2460 Mer Molécules Santé, Institut Universitaire Mer et Littoral - FR3473 CNRS, 72085, Le Mans Cedex, France.
Laboratoire d'Ecotoxicologie Marine et Environnementale, Université de Sfax, Sfax, Tunisia.
Environ Sci Pollut Res Int. 2015 Nov;22(22):17290-302. doi: 10.1007/s11356-014-3971-8. Epub 2014 Dec 20.
This study investigates cadmium effects on key messenger RNA (mRNA) expression (MT, MnSOD, CuZnSOD, CAT, ABCB1, HSP70, and CO1) by qPCR in the cockle Cerastoderma glaucum after chronic exposure to two high but environmentally relevant concentrations of CdCl2 (50 μg/L and 5 mg/L) for 12 h to 18 days. Cd accumulation measured in cockles' tissues is significantly higher in both treatment conditions compared to controls and in a dose-dependent manner. Stress on stress tests performed at different times of the experiment clearly demonstrated that exposure to both concentrations of Cd significantly affects cockle survival time in air. Important changes in gene transcription were also highlighted. In particular, MT, HSP70, CAT, and CuZnSOD seem to be relevant biomarkers of Cd exposure because (1) their mRNA levels increase upon exposure and (2) they are highly correlated to Cd accumulation in tissues. Results may be useful for control strategies and for the use of cockles as sentinel organisms.
本研究通过定量聚合酶链反应（qPCR），调查了在长期暴露于两种高浓度但与环境相关的氯化镉（CdCl₂，50 μg/L和5 mg/L）12小时至18天后，镉对鸟蛤（Cerastoderma glaucum）关键信使核糖核酸（mRNA）表达（MT、MnSOD、CuZnSOD、CAT、ABCB1、HSP70和CO1）的影响。与对照组相比，在两种处理条件下，鸟蛤组织中测量到的镉积累均显著更高，且呈剂量依赖性。在实验不同时间进行的应激测试表明，暴露于两种浓度的镉均显著影响鸟蛤在空气中的存活时间。基因转录也出现了重要变化。特别是，MT、HSP70、CAT和CuZnSOD似乎是镉暴露的相关生物标志物，因为（1）它们的mRNA水平在暴露后升高，（2）它们与组织中的镉积累高度相关。研究结果可能有助于制定控制策略，以及将鸟蛤用作指示生物。
