Description
Bisphenol S (BPS) is widely used to replace earlier-eliminated BPA. We evaluated the effect of acute in vivo BPS exposure on oocyte quality using eight-weeks-old ICR female mice (N = 15 per experimental group), exposed to vehicle or BPS1-BPS4 (0.001, 0.1, 10, and 100 ng BPS x g bw-1 x day-1, respectively). Oocytes were isolated and matured in vitro. Thereafter, we observed that BPS exposure increases aberrant spindle formation in mature oocytes and induces DNA damage. Moreover, BPS3 significantly increases chromatin repressive marks 5-methyl cytosine (5meC) and H3K27me2 in immature oocytes. In the BPS2 group (0.1 ng x g bw-1 x day-1), the increase in 5meC arises during oocyte maturation. Transcriptome analysis shows 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.