a Department of Biology , Norwegian University of Science and Technology , Trondheim , Norway.
J Toxicol Environ Health A. 2014;77(9-11):506-15. doi: 10.1080/15287394.2014.886983.
Crude oil is a complex mixture of compounds of which the water-soluble fraction (WSF) is considered to be bioavailable and potentially toxic to aquatic biota. Containing numerous compounds, WSF becomes a source of multiple chemical stressors to wildlife when introduced into the environment. To study the combined effects of WSF components on aquatic biota, the model species zebrafish (Danio rerio Hamilton) was exposed for 24 or 72 h to 10 or 50% WSF solution of known composition, generated from artificially weathered North Sea crude oil. Hepatic expression of genes involved in the aryl hydrocarbon receptor-cytochrome P-450 1A (AhR-CYP1A) pathway (AhR2, AhRR1, CYP1A1) and steroidogenesis (StAR, CYP11A, 3β-HSD, CYP19A, CYP19B) was measured, as well as estrogen receptors ERα and ERβ1. Induction of CYP1A and particularly of AhRR1 was observed while ERα and steroidogenic enzymes CYP11A and 3β-HSD were downregulated. Regression analysis demonstrated a negative relationship between AhR-CYP1A pathway and endocrine transcript levels, although causality remains to be established. These findings indicate that exposure to WSF of oil disrupts steroidogenesis and may therefore constitute a potential risk for reproductive ability of aquatic organisms. In addition, it is proposed that hepatic gene expression of AhRR1 may serve as a novel biomarker of WSF exposure.
原油是一种复杂的化合物混合物，其中水溶性部分（WSF）被认为是具有生物利用度的，并且对水生生物具有潜在毒性。WSF 含有许多化合物，当它进入环境时，会成为多种化学胁迫源，对野生动物造成影响。为了研究 WSF 成分对水生生物的综合影响，选用模式生物斑马鱼（Danio rerio Hamilton）进行实验，斑马鱼在 10%或 50%已知组成的 WSF 溶液中暴露 24 或 72 小时，这些 WSF 溶液是由人工风化的北海原油生成的。测量了与芳烃受体-细胞色素 P-450 1A（AhR-CYP1A）途径（AhR2、AhRR1、CYP1A1）和类固醇生成（StAR、CYP11A、3β-HSD、CYP19A、CYP19B）相关的基因在肝组织中的表达，以及雌激素受体 ERα 和 ERβ1。结果观察到 CYP1A 和特别是 AhRR1 的诱导，而 ERα 和类固醇生成酶 CYP11A 和 3β-HSD 被下调。回归分析表明，AhR-CYP1A 途径和内分泌转录水平之间存在负相关，尽管因果关系尚待确定。这些发现表明，暴露于 WSF 会破坏类固醇生成，因此可能对水生生物的生殖能力构成潜在风险。此外，提出肝组织 AhRR1 的基因表达可以作为 WSF 暴露的新型生物标志物。
