Di Poi Carole, Evariste Lauris, Séguin Alexis, Mottier Antoine, Pedelucq Julie, Lebel Jean-Marc, Serpentini Antoine, Budzinski Hélène, Costil Katherine
Normandie Université, 14032, Caen, France.
UMR Biologie des Organismes et des Ecosystèmes Aquatiques (BOREA); MNHN, UPMC, UCBN, CNRS-7208, IRD-207; IBFA, Université de Caen Basse-Normandie, Esplanade de la Paix, CS 14032, 14032, Caen Cedex 5, France.
Environ Sci Pollut Res Int. 2016 Mar;23(6):5002-18. doi: 10.1007/s11356-014-3702-1. Epub 2014 Oct 15.
The bioconcentration potential of fluoxetine (FLX) and its biological effects were investigated in juvenile Pacific oyster exposed for 28 days to environmentally relevant concentrations of FLX (1 ng L(-1), 100 ng L(-1) and up to 10 μg L(-1)). FLX bioaccumulated in oyster flesh resulting in 28-day bioconcentration factors greater than 2,000 and 10,000 by referring to wet and dry weights, respectively. Nevertheless, FLX did not induce oyster mortality, delayed gametogenesis, or lead to adverse histopathological alterations. At the two highest concentrations, despite non-optimal trophic conditions, FLX stimulated shell growth but only in a transient manner, suggesting a role of serotonin in the regulation of feeding and metabolism in bivalves. Those high concentrations seemed to drive bell-shaped responses of catalase and glutathione S-transferase activities throughout the exposure period, which may indicate the activation of antioxidant enzyme synthesis and then an enhanced catabolic rate or direct inhibition of those enzymes. However, no clear oxidative stress was detected because no strong differences in thiobarbituric acid-reactive substance (TBARS) content (i.e. lipid peroxidation) were observed between oyster groups, suggesting that cellular defence mechanisms were effective. These results demonstrate the importance of considering additional biomarkers of oxidative stress to obtain a comprehensive overview of the FLX-induced changes in marine bivalves exposed under realistic conditions. Considering the battery of biomarkers used, FLX appears to induce little or no effects on oyster physiology even at a concentration of 10 μg L(-1). These results do not confirm the lowest observed effect concentration (LOEC) values reported by some authors in other mollusc species.
研究了氟西汀（FLX）在环境相关浓度（1 ng L⁻¹、100 ng L⁻¹和高达10 μg L⁻¹）下对太平洋牡蛎幼体暴露28天的生物富集潜力及其生物学效应。FLX在牡蛎肉中生物累积，以湿重和干重计，28天的生物富集系数分别大于2000和10000。然而，FLX并未导致牡蛎死亡、延迟配子发生或引起不良的组织病理学改变。在两个最高浓度下，尽管营养条件不理想，但FLX刺激了贝壳生长，但只是短暂的，这表明血清素在双壳贝类摄食和代谢调节中起作用。这些高浓度似乎在整个暴露期间驱动了过氧化氢酶和谷胱甘肽S-转移酶活性的钟形反应，这可能表明抗氧化酶合成的激活，进而分解代谢率提高或这些酶的直接抑制。然而，未检测到明显的氧化应激，因为在牡蛎组之间未观察到硫代巴比妥酸反应性物质（TBARS）含量（即脂质过氧化）的强烈差异，这表明细胞防御机制是有效的。这些结果表明，考虑氧化应激的其他生物标志物对于全面了解在实际条件下暴露的海洋双壳贝类中FLX诱导的变化非常重要。考虑到所使用的一系列生物标志物，即使在10 μg L⁻¹的浓度下，FLX对牡蛎生理似乎也几乎没有影响。这些结果未证实一些作者在其他软体动物物种中报道的最低观察效应浓度（LOEC）值。
