Exposure to PBDE47 affects mouse oocyte quality via mitochondria dysfunction-induced oxidative stress and apoptosis.

Abstract

2, 2', 4, 4'-Tetrabrominated diphenyl ether (PBDE47) is the most abundant homologues in polybrominated diphenyl ethers (PBDEs) and is used widely in daily life as a brominated flame retardant. It has been shown that PBDE47 has neurotoxicity, thyroid toxicity, and also is reported to have reproductive toxicity, which can impair the follicular function of female rats and activate ovarian endoplasmic reticulum stress, leading to ovarian damage. However, the toxicity of PBDE47 to the quality of mammalian oocyte has not been reported. In this study, we reported that PBDE47 exposure affected the mouse ovarian and uterine. We also showed that oocyte number reduced and meiotic maturation competence decreased. Moreover, PBDE47 exposure disrupted actin filaments distribution, and also changed the level of histone methylation. Based on the genome-wide sequencing we showed that PBDE47 altered multiple gene expression in mouse oocytes. PBDE47 exposure caused mitochondria dysfunction, showing with aberrant distribution and mitochondrial membrane potential. In addition, our results suggested that PBDE47 induced early apoptosis, which was caused by oxidative stress, showing with increased ROS level and positive Annexin-V signal. In conclusion, our results indicated that PBDE47 exposure affected the maturation of mouse oocyte via its effects on mitochondria function, ROS level and its related apoptosis.