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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, METHODS, METHODS, METHODS, METHODS, RESULTS. Meshes: Animals, Apoptosis, Benzo(a)pyrene, Blastocyst, Blastomeres, Cell Differentiation, Cells, Cultured, Embryonic Development, Embryonic Stem Cells, Female, Mice, Reactive Oxygen Species.
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Does benzo ( a ) pyrene disrupt mouse preimplantation embryo development? Context: To determine the effects of Benzo(a)pyrene (BaP) on the development of early preimplantation embryo by exposure to physiologic concentrations of BaP based on a previous report in human ovarian follicular fluid and serum. Zygotes were cultured in 5 nM or 50 nM BaP and then examined for development efficiency, embryo quality, and DNA damage. In addition, embryonic stem cells (ESCs) were used as a model to test the toxic effects of BaP on inner cell mass (ICM) of blastocysts. Laboratory. CD1 mice. Mouse zygotes and ESCs were cultured in medium with 5 nM or 50 nM BaP. The percentage (rate) of blastocyst development, reactive oxygen species level, and quality of embryos assessed by total cell number, cell apoptosis, Oct4- and Nanog-positive cell ratio, and DNA damage on genomic and telomeric DNA were compared between dimethyl sulfoxide control and BaP treatments. The BaP-treated zygotes exhibited significantly higher reactive oxygen species activity, which might lead to more cell apoptosis, low ratio of Nanog- or Oct4-positive ICM cells, and increasing DNA damage in both genomic and telomeric DNA in blastocysts. By using mouse ESCs derived from ICM cells as a model, we showed that pluripotent cells might also show serious DNA damage after a brief exposure to BaP.
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Our data show that BaP could seriously disrupt cell growth and genomic DNA stability and increase cell apoptosis in mouse preimplantation embryo development. Final Decision: yes