UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, Quinta da Torre, 2829-516 Caparica, Portugal; Departamento de Biologia & CESAM & ECOMARE, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
MARE - Marine and Environmental Sciences Centre, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal.
Sci Total Environ. 2019 Mar 1;654:250-263. doi: 10.1016/j.scitotenv.2018.11.064. Epub 2018 Nov 6.
Scientists are currently faced with the challenge of assessing the effects of anthropogenic stressors on aquatic ecosystems. Cellular stress response (CSR) biomarkers are ubiquitous and phylogenetically conserved among metazoans and have been successfully applied in environmental monitoring but they can also vary according to natural biotic and abiotic factors. The reported variability may thus limit the wide application of biomarkers in monitoring, imposing the need to identify variability levels in the field. Our aim was to carry out a comprehensive in situ assessment of the CSR (heat shock protein 70 kDa, ubiquitin, antioxidant enzymes) and oxidative damage (lipid peroxidation) in wild populations across marine taxa by collecting fish, crustaceans, mollusks and cnidarians during two different seasons (spring and summer) and two habitat types (coast and estuary). CSR end-point patterns were different between taxa with mollusks having higher biomarker levels, followed by the cnidarians, while fish and crustaceans showed lower biomarker levels. The PCA showed clear clusters related to mobility/sessile traits with sessile organisms showing greater levels (>2-fold) of CSR proteins and oxidative damage. Mean intraspecific variability in the CSR measured by the coefficient of variation (% CV) (including data from all seasons and sites) was elevated (35-94%). Overall, there was a seasonal differentiation in biomarker patterns across taxonomic groups, especially evident in fish and cnidarians. A differentiation in biomarker patterns between habitat types was also observed and associated with phenotypic plasticity or local adaptation. Overall, specimens collected in the estuary had lower biomarker levels when compared to specimens collected in the coast. This work highlights the importance of assessing baseline biomarker levels across taxa, seasons and habitats prior to applying biomarker analyses in environmental monitoring. Selecting bioindicator species, defining sampling strategies, and identifying confounding factors are crucial preliminary steps that ensure the success of biomarkers as powerful tools in biomonitoring.
科学家目前面临着评估人为压力源对水生生态系统影响的挑战。细胞应激反应 (CSR) 生物标志物在后生动物中普遍存在且在进化上保守，已成功应用于环境监测，但它们也可能因自然生物和非生物因素而有所不同。因此，所报道的可变性可能会限制生物标志物在监测中的广泛应用，需要在现场确定可变性水平。我们的目的是通过在两个不同季节（春季和夏季）和两个生境类型（沿海和河口）采集鱼类、甲壳类动物、软体动物和刺胞动物，对海洋分类群中的 CSR（热休克蛋白 70kDa、泛素、抗氧化酶）和氧化损伤（脂质过氧化）进行全面的现场评估。CSR 终点模式在不同分类群之间存在差异，软体动物的生物标志物水平较高，其次是刺胞动物，而鱼类和甲壳类动物的生物标志物水平较低。PCA 显示与移动性/固着特征相关的清晰聚类，固着生物表现出更高水平的 CSR 蛋白和氧化损伤（>2 倍）。通过变异系数（%CV）测量的 CSR 种内变异性（包括所有季节和地点的数据）较高（35-94%）。总体而言，生物标志物模式在分类群之间存在季节性差异，尤其是在鱼类和刺胞动物中。在生境类型之间也观察到生物标志物模式的分化，与表型可塑性或局部适应有关。总体而言，与在沿海地区采集的标本相比，在河口采集的标本的生物标志物水平较低。这项工作强调了在将生物标志物分析应用于环境监测之前，在分类群、季节和生境中评估基线生物标志物水平的重要性。选择生物指标物种、定义采样策略和确定混杂因素是确保生物标志物作为生物监测有力工具成功的关键初步步骤。
