There is sparse information about the evaluation of the effects on ova of estrogen inhibition in fish. In this study, two exposure experiments were performed. First, adult zebrafish were exposed to aromatase inhibitor prochloraz (PCZ) (0, 3, 30, or 300 μg/L) for 21 days, and the developmental toxicity of larval offspring was evaluated. PCZ markedly decreased 17β-estradiol (E2) and vitellogenin (vtg) concentrations in plasma of females and suppressed spawned egg numbers. PCZ exposure caused bioaccumulation in ova and resulted in a significant decrease in the body length of larval offspring in 300 μg/L PCZ, but unexpectedly, it did not alter the vtg content of ova. Second, adult zebrafish were exposed to 0 or 300 μg/L PCZ for 21 days, and responses of the transcriptome and proteome in ova were characterized. Although a 21 day treatment with PCZ resulted in bioaccumulation of PCZ in ova, it was not responsible for the observed inhibition of body length growth of larval offspring as evidenced by PCZ microinjection. Furthermore, exposure of adult zebrafish to PCZ significantly downregulated mRNA expression of retinol binding protein 4 (rbp4) and changed protein concentrations related to mitochondrial energy metabolism in ova, and those changes might be responsible for the inhibition of growth of larval offspring.
Environmental Science and Technology Letters
Department of Biology

Dang, Y. (Yao), Sun, Q. (Qian), Letcher, R.J, & Liu, C. (Chunsheng). (2018). Unexpected Observations: Exposure to Aromatase Inhibitor Prochloraz Did Not Alter the Vitellogenin Content of Zebrafish Ova but Did Inhibit the Growth of Larval Offspring. Environmental Science and Technology Letters, 5(11), 629–634. doi:10.1021/acs.estlett.8b00486