Expression data from mouse oocytes treated with low-dose bisphenol S

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. We used microarray aproach to unravel gene expression differences triggered by the administration of BPS at different concentrations in mouse oocytes. Six- to seven-week-old ICR mice were purchased from Velaz Ltd. (Prague, Czech Republic). Mice were kept under 12 hours light-dark cycle, fed phyto-oestrogen-free diet 1814P (Altromin) and given access to ultra pure water ad libitum. Animals were randomly separated into five groups (N = 3 each, N = 4 for the transcriptomic experiment) and allowed to acclimate for at least one week. Each group was treated with one of four different BPS doses (0.001, 0.1, 10, and 100 ng BPS x g bw-1 x day-1, hereafter named BPS1, BPS2, BPS3, and BPS4, respectively). Only BPS2 was used for the transcriptomic experiment. BPS was dissolved in 50 μl 50% glycerol containing 0.1% DMSO and administered daily for 7 days by oral gavage. After the exposure period, mice were euthanised by cervical dislocation, and their ovaries were collected for RNA extraction and further experiments.