Epigenetic Influences of Bisphenol A on Male Reproductive Toxicity in Zebrafish

doi:10.3969/j.issn.1674-5817.2012.01.009

Abstract

Abstract: Objective To investigate the epigenetic modifications of zebrafish sperm maturation and embryo development by bisphenol A (BPA). Methods 20 dpf juvenile zebrafish were exposed to ethanol solution (control groups), BPA solution of 0.5mg/Land 1.5 mg/L (treatment groups) until 100 dph. As for the male selected from each group, the gonadal Dnmts mRNA expression levels were tested by quantitative PCR, the gonadal genome methylation levels were measured by immunohistochemistry. In addition, the levels of histone methylation including H3K9me3, H3K4me3, H3K27me3 and H3K36me3 were detected using Western-blot and immunohistochemistry. Males of each group were mated with untreated female fish to observe and record the indicators relating to embryonic stage. Results The expression levels of Dnmt1、dnmt6、dnmt7、dnmt8 mRNA in BPA-treated groups increased significantly compared to the control group (P<0.05). Levels of genome DNA methylation and H3K9me3 in mature sperm of BPA 1.5 mg/L-exposed group increased significantly, while the number of eggs of female fish which mated with this group is reduced to 63%±2.49% of these fish with control group, the 12h embryonic mortality increased to 202.53%±6.21% and the 72 embryonic malformations increased to 399.08%±12.16%, these differences are of statistical significance (P<0.05). Conclusion BPA exposure selectively raised levels of DNA methylation and histone H3K9me3 in mature sperm of zebrafish, these changes may be an important foundation of the increased developmental abnormalities of F1 offspring.

Key words: Zebrafish, Bisphenol A, DNA methylation, Histone, Epigenetic

CLC Number:

Q95-33

QIAO Kun, LIU Yuan-yuan, LI Yu-hua, WANG Yu-zhu, DING Xun-cheng, LI Wei-hua, LI Runsheng. Epigenetic Influences of Bisphenol A on Male Reproductive Toxicity in Zebrafish[J]. Laboratory Animal and Comparative Medicine, 2012, 32(1): 30-37.

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