MOE Key Laboratory of Aquatic Product Safety, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, People's Republic of China.
Department of Biology, Hong Kong Baptist University, Hong Kong, China.
Aquat Toxicol. 2014 Oct;155:43-51. doi: 10.1016/j.aquatox.2014.06.003. Epub 2014 Jun 13.
We studied the effects of endocrine disrupting compounds nonylphenol (NP) and letrozole (LE) on the male goldfish Carassius aumtus. Exposure to NP (20 μg l(-1)) alone caused a significant up-regulation in the expression of aromatase, estrogen receptors and vitellogenin (VTG) genes, an increase in hepatic and plasma VTG concentration, but no obvious testicular impairment. Exposure to LE (1 mg kg(-1)) alone resulted in a significant decline in aromatase activity, reduced levels of plasma 17β-estradiol (E2), and enhanced sperm maturation. Co-exposure with LE (1 mg kg(-1)) could only partially affect some of the estrogenic effects caused by NP (20 μg l(-1)) (i.e. expression of hepatic and brain estrogen receptor genes, hepatic VTG concentration), but inhibit other estrogenic effects (i.e. brain and testicular aromatase activity, plasma E2). In addition, co-exposure resulted in impairment of liver mitochondria (i.e. detachment of ridges from the membrane, and uneven distribution of the cytoplasm with clusters of glycogen granules), but did not cause significant damage to the testes (i.e. the morphology, the spermatogonia and spermatozoa densities). Our results clearly showed that nonylphenol and letrozole co-exposure could induce profound effects on fish, and highlighted the importance of adopting multiple toxicological endpoints when evaluating the combined effects of endocrine disrupting compounds.
我们研究了内分泌干扰化合物壬基酚（NP）和来曲唑（LE）对雄性金鱼（Carassius aumtus）的影响。单独暴露于 NP（20μg/L）会导致芳香酶、雌激素受体和卵黄蛋白原（VTG）基因的表达显著上调，肝和血浆 VTG 浓度增加，但睾丸没有明显损伤。单独暴露于 LE（1mg/kg）会导致芳香酶活性显著下降，血浆 17β-雌二醇（E2）水平降低，并促进精子成熟。与 LE（1mg/kg）共同暴露只能部分影响 NP（20μg/L）引起的一些雌激素效应（即肝和脑雌激素受体基因的表达、肝 VTG 浓度），但抑制其他雌激素效应（即脑和睾丸芳香酶活性、血浆 E2）。此外，共同暴露会导致肝线粒体损伤（即脊从膜上分离，细胞质不均匀分布，伴有糖原颗粒簇），但不会对睾丸造成明显损伤（即形态、精原细胞和精子密度）。我们的研究结果清楚地表明，壬基酚和来曲唑的共同暴露会对鱼类产生深远的影响，并强调在评估内分泌干扰化合物的联合效应时，采用多种毒理学终点的重要性。
