Bebianno M J, Géret F, Hoarau P, Serafim M A, Coelho M R, Gnassia-Barelli M, Roméo M
CIMA, Faculty of Marine and Environmental Sciences, University of Algarve, Campus de Gambelas, 8000 Faro, Portugal.
Biomarkers. 2004 Jul-Oct;9(4-5):305-30. doi: 10.1080/13547500400017820.
The clam Ruditapes decussatus is distributed worldwide and due to its ecological and economical interest has been proposed as a bioindicator in areas where mussels are not available. The accumulation of several anthropogenic compounds in their tissues suggests that they possess mechanisms that allow them to cope with the toxic effects of these contaminants. Besides pollutant uptake, the use of biomarkers is pointed out in this paper since it is a promising approach to monitor the effect of these contaminants in the marine environment. Biomarkers complement the information of the direct chemical characterization of different types of contaminants. Therefore, the aim of this paper is to review the role of several biomarkers: (metallothioneins (MT), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (GPx) (total and selenium-dependent), lipid peroxidation (measured as MDA, one of the final products of lipid peroxidation), glutathione S-transferase (GST) and acetylcholinesterase (AChE), measured in different tissues of the clam R. decussatus, in laboratory conditions and under various environmental stresses, in two ecosystems (Ria Formosa lagoon- Portugal) and Bizerta lagoon (Tunisia) in a perspective of a multibiomarker approach to assess environmental changes. Experiment and field studies are in good agreement since MT levels, especially in the gills, the first target tissue of these contaminants, can be used as biomarker of exposure to Cd. GPx and MDA may also be determined in this respect. AChE activity is inhibited by pesticide and, to a less extent, by metal exposure in the gills and whole soft body of clams. However, the induction of GST isoforms experimentally demonstrated is not observed in the field because only global GST activity was determined. The whole set of results opens new research perspectives for the use of this species to assess the effect of mixtures of pollutants in the aquatic environment.
波纹巴非蛤分布于世界各地，由于其具有生态和经济价值，在没有贻贝的地区被提议作为生物指示物种。其组织中多种人为化合物的积累表明，它们拥有能够应对这些污染物毒性影响的机制。除了污染物吸收外，本文还指出了生物标志物的应用，因为它是监测这些污染物对海洋环境影响的一种有前景的方法。生物标志物补充了不同类型污染物直接化学表征的信息。因此，本文的目的是综述几种生物标志物的作用：（金属硫蛋白（MT）、超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPx）（总酶和硒依赖性酶）、脂质过氧化（以丙二醛（MDA）衡量，脂质过氧化的最终产物之一）、谷胱甘肽S-转移酶（GST）和乙酰胆碱酯酶（AChE）），这些生物标志物在实验室条件下和各种环境胁迫下，于波纹巴非蛤的不同组织中进行测定，涉及两个生态系统（葡萄牙福尔摩沙潟湖）和比塞大潟湖（突尼斯），从多生物标志物方法的角度评估环境变化。实验研究和实地研究结果吻合良好，因为MT水平，尤其是在鳃中，作为这些污染物的首要靶组织，可作为镉暴露的生物标志物。在这方面也可以测定GPx和MDA。AChE活性在蛤的鳃和整个软体中会受到农药抑制，在较小程度上也会受到金属暴露的抑制。然而，在实地未观察到实验所证明的GST同工型的诱导，因为仅测定了总GST活性。所有这些结果为利用该物种评估水环境中污染物混合物的影响开辟了新的研究视角。
