Comparison of the effects of BPA and BPAF on oocyte spindle assembly and polar body release in mice.
Bisphenol AF (BPAF), a homolog of bisphenol A (BPA), is a widely used environmental chemical that has adverse effects on reproduction. The aim of this study was to analyse the effects of BPA and BPAF exposure on oocyte maturation in vitro. Oocytes were cultured in the presence of BPA or BPAF (2, 20, 50 or 100 μg/ml) for 18 h. At concentrations of 50 and 100 μg/ml, BPA and BPAF inhibited oocyte maturation, with BPAF treatment causing a sharp decrease in the number of oocytes reaching maturity. Oocytes were exposed to BPA or BPAF at 2 μg/ml and cultured for different durations (6, 9, 12, 15 or 18 h). Both BPAF and BPA caused a cell cycle delay under these conditions. Oocytes cultured in the presence of BPA or BPAF (50 μg/ml) for 21 h were tested for the localization of α-tubulin and MAD2 using immunofluorescence. High concentrations of BPAF induced cell cycle arrest through the activation of the spindle assembly checkpoint. After 12 h of culture in BPAF (50 μg/ml), oocytes were transferred to control medium for 9 h. Only 63.3% oocytes treated in this manner progressed to metaphase II (MII). Oocytes exposed to high doses of BPA experienced a cell cycle delay, but managed to progress to MII when the culture period was prolonged. In addition, MAD2 was localized in the cytoplasm of these oocytes. In conclusion, both BPAF and BPA exposure affected oocyte maturation, however BPAF and BPA have differential effects on SAC activity.
Laboratory of Animal Reproduction and Development,Graduate School of Agricultural Science,Tohoku University,Sendai 981-8555,Japan.
Kei
K
Nakano
Laboratory of Animal Reproduction and Development,Graduate School of Agricultural Science,Tohoku University,Sendai 981-8555,Japan.
Manami
M
Nishio
Laboratory of Animal Reproduction and Development,Graduate School of Agricultural Science,Tohoku University,Sendai 981-8555,Japan.
Norio
N
Kobayashi
Laboratory of Animal Reproduction and Development,Graduate School of Agricultural Science,Tohoku University,Sendai 981-8555,Japan.
Yuuki
Y
Hiradate
Laboratory of Animal Reproduction and Development,Graduate School of Agricultural Science,Tohoku University,Sendai 981-8555,Japan.
Yumi
Y
Hoshino
Laboratory of Animal Reproduction and Development,Graduate School of Agricultural Science,Tohoku University,Sendai 981-8555,Japan.
Eimei
E
Sato
Laboratory of Animal Reproduction and Development,Graduate School of Agricultural Science,Tohoku University,Sendai 981-8555,Japan.
Kentaro
K
Tanemura
D000818:Animals; D001559:Benzhydryl Compounds / Q000494:pharmacology*; D059447:Cell Cycle Checkpoints / Q000187:drug effects; D002478:Cells, Cultured; D003593:Cytoplasm / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D052244:Endocrine Disruptors / Q000494:pharmacology; D004968:Estrogens, Non-Steroidal / Q000494:pharmacology; D005260:Female; D064246:Mad2 Proteins / Q000378:metabolism; D008813:Mice, Inbred ICR; D018613:Microscopy, Confocal; D009865:Oocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D010636:Phenols / Q000494:pharmacology*; D059705:Polar Bodies / Q000187:drug effects* / Q000378:metabolism; D008941:Spindle Apparatus / Q000187:drug effects* / Q000378:metabolism; D013997:Time Factors; D014404:Tubulin / Q000378:metabolism; D000098826:Bisphenol A Compounds; D005466:Fluorocarbons
D001559:Benzhydryl Compounds; D052244:Endocrine Disruptors; D004968:Estrogens, Non-Steroidal; D064246:Mad2 Proteins; D010636:Phenols; D014404:Tubulin; C577698:Mad2l1 protein, mouse; C006780:bisphenol A; D000098826:Bisphenol A Compounds; C583074:bisphenol AF; D005466:Fluorocarbons
BPA; BPAF; In vitro maturation; MAD2; Oocyte