Department of Biology, University of Bergen, Bergen, Norway.
Chemosphere. 2013 Nov;93(10):2356-64. doi: 10.1016/j.chemosphere.2013.08.033. Epub 2013 Sep 12.
Oil pollution from various sources, including exploration, production and transportation, is a growing global concern. The highest toxicity of hydrocarbon pollutants is associated with the water-soluble phase compounds, including naphthenic acids, a known component found in all hydrocarbon deposits. Recently, naphthenic acids (NAs) have shown estrogenic and anti-androgenic effects in vitro. For this reason we investigated the potential effects of two commercial mixtures of naphthenic acids on fish in vivo, using the three-spined stickleback (Gasterosteus aculeatus) as a model species. Anti-androgenic and estrogenic properties of tested compounds were evaluated using the androgenized female stickleback screen (AFSS) and a variant of the 21-d fish screen (TG230) respectively. One-dimensional gas chromatography-mass spectrometry (GC-MS) showed that the complex commercial NAs mixtures were dominated by acyclic carboxylic acids. In one experiment (freshwater) we found a clear effect of NA exposure on spiggin levels; this was contrary to our hypothesis since NAs enhanced the androgenic potency of DHT (when co-administered) without inducing spiggin when tested in the absence of DHT. Exposure to NAs did not have a statistically significant effect on vitellogenin (Vtg) production in male stickleback, although the Vtg responses were increasing with increasing exposure concentrations. This study shows that in contrast to previous in vitro data, NAs did not exhibit either estrogenic or anti-androgenic properties in vivo, at the concentrations tested. On the contrary, at least in freshwater, NAs appear to have an overall androgenic effect that is not mediated via the androgen receptor involved in spiggin synthesis. Possible reasons for this discrepancy between in vitro and in vivo results as well as between our studies are discussed.
石油污染来自于各种来源，包括勘探、生产和运输，是一个日益严重的全球性问题。烃类污染物的最高毒性与水溶性相化合物有关，包括环烷酸，这是所有碳氢化合物沉积物中已知的成分。最近，环烷酸（NAs）在体外表现出雌激素和抗雄激素作用。因此，我们使用三刺棘鱼（Gasterosteus aculeatus）作为模型物种，研究了两种商业环烷酸混合物对鱼类的潜在影响。使用雄激素化雌性棘鱼筛选（AFSS）和 21 天鱼类筛选（TG230）的变体，分别评估了测试化合物的抗雄激素和雌激素特性。一维气相色谱-质谱（GC-MS）表明，复杂的商业 NAs 混合物主要由无环羧酸组成。在一项实验（淡水）中，我们发现 NA 暴露对 spiggin 水平有明显影响；这与我们的假设相反，因为 NAs 增强了 DHT 的雄激素效力（当共同给药时），而在没有 DHT 的情况下测试时，不会诱导 spiggin。暴露于 NAs 对雄性棘鱼的卵黄蛋白原（Vtg）产生没有统计学上的显著影响，尽管随着暴露浓度的增加，Vtg 反应呈上升趋势。这项研究表明，与之前的体外数据相反，在测试浓度下，NAs 在体内既没有表现出雌激素也没有表现出抗雄激素特性。相反，至少在淡水中，NAs 似乎具有整体雄激素作用，而不是通过参与 spiggin 合成的雄激素受体介导。讨论了这种体外和体内结果之间以及我们的研究之间存在差异的可能原因。
