Gagné F, Blaise C, Pellerin J, Fournier M, Gagnon C, Sherry J, Talbot A
Fluvial Ecosystem Research Section, Environment Canada, 105 McGill Street, Montréal, Quebec, Canada.
Sci Total Environ. 2009 Nov 1;407(22):5844-54. doi: 10.1016/j.scitotenv.2009.07.007. Epub 2009 Aug 20.
This study examined the relationships between population characteristics and the expression of physiological biomarkers of stress in an intertidal clam population under pollution at sites differing in thermal history and coastline distance. The clam population metrics were age distribution, growth, condition factor, distance of the clam beds from the shore, and gonad development. Physiological biomarkers comprised biomarkers of defence such as superoxide dismutase, labile IIb metals in tissues, redox status of metallothioneins and glutathione S-transferase, of tissue damage such as lipid peroxidation and DNA strand breaks, of reproduction as determined by vitellogenin-like proteins and gonadosomatic index and immunocompetence such as phagocytosis and hemocyte viability. Age-related pigments were also examined to compare the physiological age of the clams with their chronological age. The results showed that all the above biomarkers were significantly affected at one of the two polluted sites at least. Distance from the shore was significantly correlated with most (81%) of the biomarkers examined. Clams collected at one polluted site were physiologically older than clams from the corresponding reference site. Canonical and adaptive regression (artificial neural networks) analyses found that the biomarkers measured in this study were able to predict the ecologically relevant endpoints. Biomarkers implicated in defense mechanisms, tissue damage and age-related pigments were most closely related to the clam population characteristics. Sensitivity analysis of the learning algorithm found that the following physiological and biochemical markers were the most predictive, in decreasing order, of clam population characteristics: glutathione S-transferase, phagocytosis, age pigments, lipid peroxidation in the gills, labile IIb metals and total MT levels. These biomarkers were affected by the distance of the clam beds from the shore, site quality (pollution) and reproduction activity.
本研究调查了在热历史和海岸线距离不同的受污染地点，潮间带蛤蜊种群的种群特征与应激生理生物标志物表达之间的关系。蛤蜊种群指标包括年龄分布、生长、状况因子、蛤床与海岸的距离以及性腺发育。生理生物标志物包括防御生物标志物，如超氧化物歧化酶、组织中的不稳定IIb金属、金属硫蛋白和谷胱甘肽S-转移酶的氧化还原状态；组织损伤生物标志物，如脂质过氧化和DNA链断裂；繁殖生物标志物，由类卵黄蛋白原样蛋白和性腺体指数确定；以及免疫能力生物标志物，如吞噬作用和血细胞活力。还检测了与年龄相关的色素，以比较蛤蜊的生理年龄和实际年龄。结果表明，上述所有生物标志物至少在两个受污染地点之一受到了显著影响。与海岸的距离与所检测的大多数（81%）生物标志物显著相关。在一个受污染地点采集的蛤蜊生理上比相应对照地点的蛤蜊更老。典型和自适应回归（人工神经网络）分析发现，本研究中测量的生物标志物能够预测生态相关终点。涉及防御机制、组织损伤和与年龄相关色素的生物标志物与蛤蜊种群特征关系最为密切。学习算法的敏感性分析发现，以下生理和生化标志物对蛤蜊种群特征的预测性最强，按降序排列为：谷胱甘肽S-转移酶、吞噬作用、年龄色素、鳃中的脂质过氧化、不稳定IIb金属和总金属硫蛋白水平。这些生物标志物受到蛤床与海岸的距离、地点质量（污染）和繁殖活动的影响。
