Normandie Univ, UNIHAVRE, UMR-I 02 SEBIO, FR CNRS 3730 SCALE, 76600 Le Havre, France.
Université Reims Champagne Ardenne, UMR-I 02 SEBIO, 51100 Reims, France.
Water Res. 2018 Apr 1;132:124-134. doi: 10.1016/j.watres.2017.12.057. Epub 2017 Dec 27.
In a previous study, the Comet assay was optimized for Palaemon serratus prawns in order to propose a biomarker for sperm quality in this species. However, better knowledge of its basal level and its natural variability, related to intrinsic biotic and environmental abiotic factors, is required before any relevant use of this biomarker in the field. To fulfill this goal, the present study proceeded in three steps: (i) the temporal variability of DNA integrity was followed monthly in a reference population over a 2-year period, (ii) the correlation between the main intrinsic biotic (i.e. size, weight and molting stage) and abiotic factors (i.e. water temperature) were recorded in the field, and the basal DNA integrity was assessed in order to scrutinize any confounding influence of factors unrelated to toxic response, (iii) the baseline level was used to discriminate biomarker response among different stations displaying contrasting contamination levels. The results of the two-year monitoring in the reference population revealed no correlation between the levels of spermatozoa DNA damage and temperature, body size, weight or molting stage. Only a slight variability between monthly samplings was detected. On the basis of these field-collected data, we defined a reference distribution (i.e. 52.6 ± 5.6 A.U) with a threshold value (i.e. 61.7 A.U). Finally, this threshold value proved its relevance to discriminate among stations with contrasting pollution levels around the Seine Bay. Indeed, the results suggest significant DNA damage in populations nearest the Seine estuary, a major source of contaminants in the Bay, and a lower effect in populations further away from the estuary. The overall conclusion was that the Comet assay on P. serratus spermatozoa could be a useful tool for the monitoring of the toxicological print within sperm and main globally the contamination exposure of crustaceans in marine waters.
在之前的研究中，优化了对脊尾白虾精子的彗星试验，以提出该物种精子质量的生物标志物。然而，在该生物标志物在现场得到任何相关应用之前，需要更好地了解其基础水平及其与内在生物和环境非生物因素相关的自然变异性。为了实现这一目标，本研究分三步进行：（i）在两年的时间里，每月监测参考种群中 DNA 完整性的时间变化，（ii）记录现场主要内在生物因素（即大小、体重和蜕皮阶段）和非生物因素（即水温和环境因素）之间的相关性，评估基础 DNA 完整性，以仔细检查与毒性反应无关的因素的任何混杂影响，（iii）使用基线水平来区分不同污染水平的不同站点之间的生物标志物反应。参考种群两年监测的结果表明，精子 DNA 损伤水平与温度、体型、体重或蜕皮阶段之间没有相关性。仅检测到每月采样之间的细微变化。基于这些现场收集的数据，我们定义了一个参考分布（即 52.6±5.6 AU）和一个阈值（即 61.7 AU）。最后，该阈值值被证明可以用于区分具有不同污染水平的站点。事实上，结果表明，在距离塞纳河口最近的种群中存在显著的 DNA 损伤，塞纳河口是该海湾的主要污染物来源，而在远离河口的种群中则影响较小。总的结论是，脊尾白虾精子的彗星试验可以成为监测精子中毒理学印记和甲壳类动物在海洋水中整体污染暴露的有用工具。
