Department of Aquatic Ecology and Centre for Water and Environmental Research (ZWU), University of Duisburg/Essen, Universitätsstrasse 5, D-45141 Essen, Germany.
Environ Pollut. 2013 Sep;180:173-9. doi: 10.1016/j.envpol.2013.05.014. Epub 2013 Jun 13.
It is a common method to analyse physiological mechanisms of organisms - commonly referred to as biomarkers - to indicate the presence of environmental pollutants. However, as biomarkers respond to a wide range of stressors we want to direct the attention on natural stressors, i.e. on parasites. After two years maintenance under controlled conditions, roach (Rutilus rutilus) revealed no influence on levels of metallothionein by the parasite Ligula intestinalis. The same was found for Gammarus fossarum infected with Polymorphus minutus. However, the heat shock protein (HSP70) response was affected in both host-parasite systems. While the infection of roach resulted in reduced levels of HSP70 compared to uninfected roach, the infection in G. fossarum led to higher levels of HSP70. We also analysed the effect of a 14 days Cd exposure (4 μg/L) on the uninfected and infected gammarids. The exposure resulted in induced levels for both, metallothionein and HSP70 whereas the combination of stressors, parasite and exposure, revealed a decrease for levels of HSP70 in comparison to the metal exposure only. Accordingly, parasites as natural parts of aquatic ecosystems have to be considered in ecotoxicological research.
这是一种分析生物体生理机制（通常称为生物标志物）以指示环境污染物存在的常用方法。然而，由于生物标志物对多种胁迫因素有反应，我们希望将注意力集中在自然胁迫因素上，即寄生虫。在经过两年的受控条件下维持后，寄生虫 Ligula intestinalis 对罗非鱼（Rutilus rutilus）体内金属硫蛋白水平没有影响。同样，感染 Polymorphus minutus 的淡水小龙虾（Gammarus fossarum）也是如此。然而，热休克蛋白 (HSP70) 反应在这两种宿主-寄生虫系统中都受到了影响。感染罗非鱼导致 HSP70 水平降低，而感染淡水小龙虾则导致 HSP70 水平升高。我们还分析了 14 天 Cd 暴露（4μg/L）对未感染和感染的淡水小龙虾的影响。暴露导致金属硫蛋白和 HSP70 的诱导水平升高，而与仅暴露于金属相比，胁迫因素（寄生虫和暴露）的组合导致 HSP70 水平下降。因此，寄生虫作为水生生态系统的自然组成部分，在生态毒理学研究中必须加以考虑。
