Zhejiang Provincial Key Laboratory for Technology and Application of Model Organisms, Institute of Environmental Safety and Human Health, Wenzhou Medical University, Wenzhou 325035, China.
Environmental and Molecular Toxicology, The Sinnhuber Aquatic Research Laboratory and the Environmental Health Sciences Center, Oregon State University, Corvallis, OR 97333, USA.
Environ Pollut. 2016 Nov;218:702-708. doi: 10.1016/j.envpol.2016.07.064. Epub 2016 Aug 3.
Perfluorooctanesulphonic acid (PFOS) is a ubiquitous contaminant in the aquatic environment and our earlier studies demonstrated that chronic PFOS exposures lead to a female-biased sex ratio and decreased sperm quality in male zebrafish. The underlying mechanism for these reproductive effects is unknown. In the present study, 8 h post-fertilization (hpf) zebrafish were exposed to PFOS at 250 μg/L for 5 months, and the levels of sex hormones, expression of sex determination related genes, and histological and ultrastructural changes of gonads were fully characterized. During the sex differentiation period, we observed elevated estradiol (E2) and decreased testosterone (T) levels in whole tissue homogenates from PFOS exposed juveniles. In fully mature adult male fish, serum E2 levels were slightly increased, however, the estrogen receptor alpha (esr1) was significantly elevated in PFOS treated male gonads. Histological and electron microscopic examinations revealed structural changes in the gonads of PFOS exposed male and female adult zebrafish. In summary, chronic PFOS exposure disrupts sex hormone level and related gene expression and impairs gonadal development, which may contribute to the previously reported PFOS reproductive toxicity.
全氟辛烷磺酸 (PFOS) 是水生环境中普遍存在的污染物，我们之前的研究表明，慢性 PFOS 暴露会导致雄性斑马鱼出现雌性偏性性别比例和精子质量下降。这些生殖效应的潜在机制尚不清楚。在本研究中，受精后 8 小时 (hpf) 的斑马鱼在 250μg/L 的 PFOS 中暴露 5 个月，充分表征了性荷尔蒙水平、性别决定相关基因的表达以及性腺的组织学和超微结构变化。在性别分化期间，我们观察到 PFOS 暴露的幼鱼全组织匀浆中的雌二醇 (E2) 水平升高，睾丸酮 (T) 水平降低。在完全成熟的成年雄性鱼中，血清 E2 水平略有升高，但是，PFOS 处理的雄性性腺中的雌激素受体 alpha (esr1) 显著升高。组织学和电子显微镜检查显示，PFOS 暴露的雄性和雌性成年斑马鱼的性腺发生了结构变化。总之，慢性 PFOS 暴露会破坏性激素水平和相关基因表达，并损害性腺发育，这可能是先前报道的 PFOS 生殖毒性的原因。
