Impact of BPA and its analogs on sperm hyperactivity, acrosome reaction, epigenetic profiles and in vitro embryo development

Bisphenols, particularly BPA, are ubiquitous environmental contaminants known to affect male reproductive health. However, their specific impacts on sperm function and subsequent embryo development remain understudied especially for BPA's commonly used replacements, BPS and BPF. This study investigated the effects of direct sperm exposure to BPA, BPS, and BPF on fertilization capacity and embryo development using a bovine model, as translational for humans. Sperm samples were exposed to 0.05 mg/mL of each bisphenol in vitro. Parameters, including hyperactivity and acrosome reaction, as well as fertilization outcomes, such as developmental rates and blastocyst quality, were further evaluated following IVF. miRNA profiles were also analyzed in sperm and embryos to detect potential biomarkers of bisphenol exposure. We found that BPF significantly increased sperm hyperactivity, and BPA decreased acrosome reaction levels (p < 0.05). Cleavage and blastocyst rates were also notably decreased in embryos derived from BPA-exposed sperm (p < 0.05). Furthermore, blastocysts produced from BPA, BPS and BPF treated sperm all had significantly lower cell counts and increased DNA fragmentation (p < 0.05). Although no statistically significant changes in miRNA levels were observed, this study highlights some of the detrimental effects of bisphenols on bovine sperm and subsequent embryo development, with potential implications for human reproductive health.