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.
Environ Pollut. 2019 Feb;245:485-493. doi: 10.1016/j.envpol.2018.11.006. Epub 2018 Nov 12.
The interpretation of biomarkers in natura should be based on a referential of expected values in uncontaminated conditions. Nevertheless, to build a reference data set of biomarker responses in estuarine areas, which receive chronic pollution loads due to their transition position between continent and sea, is impossible. In this context, the aim of the present work was to propose the use of laboratory recovery period to define a baseline for the measurement of sperm DNA damage by Comet assay in the estuarine prawn Palaemon longirostris. For that, sperm DNA integrity was observed after both a passive (i.e. 20 days in a clean environment) and an active (i.e. forced renewal of spermatophores) recovery of wild P. longirostris specimens from the Seine estuary, in laboratory conditions. Then, the levels of sperm DNA damage recorded within the P. longirostris population of the Seine estuary, during six campaigns of sampling from April 2015 to October 2017, have been interpreted according to the defined threshold values. The results showed a persistence in the level of DNA damage after 20-day in clean environment with the passive recovery. This strategy was inconclusive to reach a baseline level but it revealed the lack of DNA repair mechanisms. For the active recovery, a decrease of 54% of the level of DNA damage has been observed after the first renewal of spermatophores and this level stabilized after the second renewal. On the basis of this second strategy, we defined a mean basal value of sperm DNA damage of 54.9 A.U. and a maximum threshold of 69.7 A.U. (i.e. 95 %CI). The analysis of the results using the reference value highlighted significant abnormal sperm DNA damage within the native population of P. longirostris from the Seine estuary on all stations during the six-sampling campaigns.
在自然状态下解释生物标志物应该基于未受污染条件下的预期值参考值。然而，由于其处于大陆和海洋之间的过渡位置，在受到慢性污染负荷的河口地区建立生物标志物反应的参考数据集是不可能的。在这种情况下，本工作的目的是提出在实验室恢复期使用来定义对通过 Comet 分析测量河口对虾 Palaemon longirostris 的精子 DNA 损伤的基线。为此，在实验室条件下，观察了来自塞纳河口的野生 Palaemon longirostris 标本在被动（即 20 天在清洁环境中）和主动（即强制更新精荚）恢复后精子 DNA 的完整性。然后，根据定义的阈值解释了在塞纳河口 Palaemon longirostris 种群中在 2015 年 4 月至 2017 年 10 月六次采样期间记录的精子 DNA 损伤水平。结果表明，在清洁环境中经过 20 天的被动恢复后，DNA 损伤水平仍然存在。这种策略无法达到基线水平，但它揭示了缺乏 DNA 修复机制。对于主动恢复，在第一次更新精荚后，DNA 损伤水平下降了 54%，并且在第二次更新后稳定下来。基于这种第二种策略，我们定义了精子 DNA 损伤的平均基础值为 54.9 A.U.和最大阈值为 69.7 A.U.（即 95%CI）。使用参考值分析结果表明，在六个采样期间，在塞纳河口 Palaemon longirostris 的自然种群中所有站点都存在显著的异常精子 DNA 损伤。
