Pesticide Chemistry Department, Faculty of Agriculture, University of Alexandria, Alex., Egypt.
Chemosphere. 2010 Mar;79(1):40-6. doi: 10.1016/j.chemosphere.2010.01.056. Epub 2010 Feb 18.
This study investigates the biomarkers of oxidative stress and heavy metal accumulation for assessing ecotoxicological effects of urban metal pollution in Alexandria city, Egypt. This investigation was performed in the digestive gland of roadside Theba pisana snails obtained from six different sites in the city. Relationships between heavy metal (Zn, Cu, Pb and Cd) concentrations and oxidative stress indicators were also examined. The results showed that mean concentrations of the measured elements (mugg(-1) dry weight) were higher in polluted sites when compared to the background levels of the reference site. The pattern of metals accumulation at all sites was Zn>Cu>Pb>Cd. In the metal polluted sites, snails displayed higher mean of catalase (CAT), glutathione peroxidase (GPx) and glutathione S-transferase (GST) activities, lower reduced glutathione (GSH) content and higher levels of lipid peroxidation (LPO) compared to snails from the reference site. All oxidative stress parameters were positively correlated to heavy metal concentrations except GSH content which exhibits negative correlation with the concentrations of these metals. Our results suggest that the tested antioxidant defenses are sensitive parameters that could be useful as oxidative stress biomarkers in snails exposed to the actual metals in the environment. These biomarkers when complemented with metal accumulation in the digestive gland of snails may provide a powerful biomonitor for the assessment of environmental metal pollution.
本研究旨在探讨氧化应激和重金属积累的生物标志物，以评估埃及亚历山大市城市金属污染的生态毒理学效应。本研究在从城市六个不同地点获得的路边斑带滨螺的消化腺中进行。还检查了重金属（Zn、Cu、Pb 和 Cd）浓度与氧化应激指标之间的关系。结果表明，与参考点的背景水平相比，污染点的测量元素（mg(-1)干重）的平均浓度更高。在所有地点，金属的积累模式均为 Zn>Cu>Pb>Cd。在金属污染点，与来自参考点的蜗牛相比，蜗牛表现出更高的过氧化氢酶（CAT）、谷胱甘肽过氧化物酶（GPx）和谷胱甘肽 S-转移酶（GST）活性、更低的还原型谷胱甘肽（GSH）含量和更高的脂质过氧化（LPO）水平。除了 GSH 含量与这些金属浓度呈负相关外，所有氧化应激参数均与重金属浓度呈正相关。我们的结果表明，测试的抗氧化防御系统是敏感参数，可作为暴露于环境中实际金属的蜗牛的氧化应激生物标志物。这些生物标志物与蜗牛消化腺中金属的积累相结合，可能为评估环境金属污染提供强大的生物监测工具。
