Bisphenol S (BPS) is widely used to replace the known endocrine disruptor BPA in various products. We evaluated the effect of acute in vivo BPS exposure on oocyte quality, simulating the oral route of exposure via oral gavage. Eight-week-old ICR female mice (N = 15 per experimental group) were exposed to vehicle or BPS1–BPS4 (0.001, 0.1, 10, and 100 ng BPS x g bw⁻¹ day⁻¹, respectively) for seven days. Oocytes were isolated and matured in vitro. We observed that BPS exposure increased aberrant spindle formation in mature oocytes and induced DNA damage. Moreover, BPS3 significantly increased the chromatin repressive marks 5-methyl cytosine (5meC) and H3K27me2 in immature oocytes. In the BPS2 group, the increase in 5meC occurred during oocyte maturation. Transcriptome analysis revealed differential expression of early embryonic development transcripts in BPS2-exposed oocytes. These findings indicate that the biological effect of BPS is non-monotonic, affecting oocyte quality even at concentrations that are orders of magnitude below those measured in humans.

双酚S（BPS）被广泛用于替代各种产品中已知的内分泌干扰物BPA。我们评估了急性体内BPS暴露对卵母细胞质量的影响，模拟了通过管饲法进行口服暴露的途径。将八周大的ICR雌性小鼠（每个实验组N = 15）暴露于媒介物或BPS1- BPS4（分别为0.001、0.1、10和100 ng BPS xg bw ^-1天^-1天），暴露7天。分离卵母细胞并在体外成熟。我们观察到BPS暴露会增加成熟卵母细胞中异常纺锤体的形成并诱导DNA损伤。此外，BPS3显着增加了未成熟卵母细胞的染色质抑制标记5-甲基胞嘧啶（5meC）和H3K27me2。在BPS2组中，卵母细胞成熟过程中5meC升高。转录组分析揭示了暴露于BPS2的卵母细胞中早期胚胎发育转录本的差异表达。这些发现表明，BPS的生物学效应是非单调的，即使浓度低于人体测得的浓度，也会影响卵母细胞的质量。