Endocrine disrupting chemicals (EDCs), like bisphenol A (BPA) and benzophenone-3 (BP-3), can interfere with hormone systems, posing risks to fertility and reproduction. Exposure to EDCs is unavoidable making it a relevant environmental health topic, however the impact of real-life EDC mixtures is largely unknown. This study explored the effects of a combined BPA and BP-3 exposure at tolerable intake levels for humans during pregnancy and early life on ovarian development and function in an established mouse model. Mice were daily exposed to concentrations of 4 µg/kg BPA orally, 50 mg/kg BP-3 dermally, and the combination of BPA+BP-3 through gestation and lactation, a susceptible developmental period. Female offspring of BPA and BP-3 exposed mice exhibited increased birth weight and elevated bodyweight by postnatal day 7. By day 30, after hormonal stimulation to induce ovulation, exposed offspring showed disrupted ovarian follicle maturation and altered ovarian response to stimulation with exogenous gonadotropins. Moreover, the number of NK cells rose in the ovaries, and genes linked to hormone signaling, hormone synthesis, and ovarian tissue remodeling were altered relative to unexposed controls. These findings suggest that early life exposure to BPA and BP-3 at environmentally relevant doses impairs ovarian development and function in mice indicating that immune cells and hormonal signaling in the ovaries are targets of endocrine disruptors at relevant concentrations. Such endocrine disruption may be compromising fertility and reproductive health in later life. Our research underscores the importance of investigating the impact of combined EDC exposure on the reproductive system.

Endocrine-disrupting chemicals such as benzophenone-3 (BP-3) can have severe consequences for human reproduction by affecting critical processes during pregnancy. To shed further light on potential harmful BP-3 actions, our current study addressed the impact of BP-3 on decidualization and trophoblast invasion. Decidualization was initiated in human endometrial stromal cells (THESC) upon treatment with a mixture of cAMP, progesterone, and estradiol. In parallel to hormonal treatment, the cells were exposed to different BP-3 concentrations ranging from 0.001 µM to 10 µM. The expression of decidualization and invasion markers was determined. Moreover, trophoblastic spheroids derived from JEG-3 cells were transferred to decidualized THESC after BP-3 exposure, and spheroid attachment and invasion were analyzed. Hormonal treatment successfully initiated decidualization in THESC, which was confirmed by increased prolactin levels and IGFBP1 and NCOA-3 mRNA expression. Notably, BP-3 exposure did not affect these markers. Furthermore, BP-3 changed neither THESC proliferation nor viability nor the frequency of cells expressing MMP2/9 or TIMP1/3. Trophoblastic spheroid attachment and outgrowth into THESC were not altered through any of the BP-3 concentrations applied. Our results do not provide evidence for an influence of BP-3 on the decidualization process and the capability of trophoblast cells to adhere and invade into endometrial stromal cells.

Mast cells (MCs) belong to the cell network that regulates uterine spiral artery remodeling (uSAR), a critical vascular adaptation supporting placental development and fetal growth. Our previous in vitro study demonstrated that human MCs promote trophoblast invasion, as well as uterine vascular smooth muscle cells (uVSMCs) migration and transition to a synthetic phenotype—essential steps for a successful uSAR. Although MCs are known targets of bisphenol A (BPA), a widespread endocrine-disrupting chemical, its impact on their supportive role in uSAR is unknown. In this study, we used murine cell lines to investigate whether BPA (0.1–100 µM) affects MC-mediated promotion of cellular processes critical for uSAR. Our results showed that BPA exposure hindered MCs’ ability to promote trophoblast invasion and the switch in uVSMCs’ synthetic phenotype and migration. The highest concentrations of BPA altered the expression of genes related to MCs activation and proliferation, and of those involved in trophoblasts invasion. In contrast, low doses induced the expression of pro-inflammatory mediators in MCs without detectable effect on trophoblasts at the transcriptional level. These findings confirmed MCs as key mediators of uSAR, and identified BPA as a disruptor of their function, emphasizing its potential harmful impact on reproductive health.