BPA induces placental trophoblast proliferation inhibition and fetal growth restriction by inhibiting the expression of SRB1

The Role of Placental DNA Methylation at Reproduction-Related Genes in Associations between Prenatal Bisphenol Analogues Exposure and the Digit Ratio in Children at Age 4: A Birth Cohort Study

Placental DNA methylation (DNAm) may be a potential mechanism underlying the effects of prenatal bisphenol analogues (BPs) exposure on reproductive health. Based on the Shanghai-Minhang Birth Cohort Study (S-MBCS), this study investigated associations of placental DNAm at reproduction-related genes with prenatal BPs exposure and children's digit ratios at age 4 using multiple linear regression models, and mediation analysis was further used to examine the mediating role of placental DNAm in the associations between prenatal BPs exposure and digit ratios among 345 mother-child pairs. Prenatal exposure to bisphenol A (BPA) was associated with hypermethylation at Protocadherin 8 (PCDH8), RBMX Like 2 (RBMXL2), and Sperm Acrosome Associated 1 (SPACA1), while bisphenol F (BPF) exposure was associated with higher methylation levels of Fibroblast Growth Factor 13 (FGF13). Consistent patterns were found in associations between higher DNAm at the 4 genes and increased digit ratios. Further mediation analysis showed that about 15% of the effect of BPF exposure on increased digit ratios was mediated by placental FGF13 methylation. In conclusion, the altered placental DNAm status might be a mediator underlying the feminizing effect of prenatal BPs exposure.

Bisphenol A induces placental ferroptosis and fetal growth restriction via the YAP/TAZ-ferritinophagy axis

Exposure to bisphenol A (BPA) during gestation leads to fetal growth restriction (FGR), whereby the underlying mechanisms remain unknown. Here, we found that FGR patients showed higher levels of BPA in the urine, serum, and placenta; meanwhile, trophoblast ferroptosis was observed in FGR placentas, as indicated by accumulated intracellular iron, impaired antioxidant molecules, and increased lipid peroxidation products. To investigate the role of ferroptosis in placental and fetal growth, BPA stimulation was performed both in vivo and in vitro. BPA exposure during gestation was associated with FGR in mice; also, it induces ferroptosis in mouse placentas and human placental trophoblast. Pretreatment with ferroptosis inhibitor ferritin-1 (Fer-1) alleviated BPA-induced oxidative damage and cell death. Notably, BPA reduced the trophoblastic expression of Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ), which regulated tissue growth and organ size. YAP or TAZ siRNA enhanced BPA-induced ferroptosis, suggesting that trophoblast ferroptosis is dependent on YAP/TAZ downregulation after BPA stimulation. Consistently, the protein levels of YAP/TAZ were also reduced in FGR placentas. Further results revealed that silencing YAP/TAZ promoted BPA-induced ferroptosis through autophagy. Pretreatment with autophagy inhibitor chloroquine (CQ) attenuated BPA-induced trophoblast ferroptosis. Ferritinophagy, an autophagic degradation of ferritin (FTH1), was observed in FGR placentas. Similarly, BPA reduced the protein level of FTH1 in placental trophoblast. Pretreatment with iron chelator desferrioxamine (DFO) and NCOA4 (an autophagy cargo receptor) siRNA weakened the ferroptosis of trophoblast after exposure to BPA, indicating that autophagy mediates ferroptosis in BPA-stimulated trophoblast by degrading ferritin. In summary, ferroptosis was featured in BPA-associated FGR and trophoblast injury; the regulation of ferroptosis involved the YAP/TAZ-autophagy-ferritin axis.

Bisphenol A induces placental ferroptosis and fetal growth restriction via the YAP/TAZ-ferritinophagy axis

Exposure to bisphenol A (BPA) during gestation leads to fetal growth restriction (FGR), whereby the underlying mechanisms remain unknown. Here, we found that FGR patients showed higher levels of BPA in the urine, serum, and placenta; meanwhile, trophoblast ferroptosis was observed in FGR placentas, as indicated by accumulated intracellular iron, impaired antioxidant molecules, and increased lipid peroxidation products. To investigate the role of ferroptosis in placental and fetal growth, BPA stimulation was performed both in vivo and in vitro. BPA exposure during gestation was associated with FGR in mice; also, it induces ferroptosis in mouse placentas and human placental trophoblast. Pretreatment with ferroptosis inhibitor ferritin-1 (Fer-1) alleviated BPA-induced oxidative damage and cell death. Notably, BPA reduced the trophoblastic expression of Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ), which regulated tissue growth and organ size. YAP or TAZ siRNA enhanced BPA-induced ferroptosis, suggesting that trophoblast ferroptosis is dependent on YAP/TAZ downregulation after BPA stimulation. Consistently, the protein levels of YAP/TAZ were also reduced in FGR placentas. Further results revealed that silencing YAP/TAZ promoted BPA-induced ferroptosis through autophagy. Pretreatment with autophagy inhibitor chloroquine (CQ) attenuated BPA-induced trophoblast ferroptosis. Ferritinophagy, an autophagic degradation of ferritin (FTH1), was observed in FGR placentas. Similarly, BPA reduced the protein level of FTH1 in placental trophoblast. Pretreatment with iron chelator desferrioxamine (DFO) and NCOA4 (an autophagy cargo receptor) siRNA weakened the ferroptosis of trophoblast after exposure to BPA, indicating that autophagy mediates ferroptosis in BPA-stimulated trophoblast by degrading ferritin. In summary, ferroptosis was featured in BPA-associated FGR and trophoblast injury; the regulation of ferroptosis involved the YAP/TAZ-autophagy-ferritin axis.

Bisphenol A triggers apoptosis in mouse pre-antral follicle granulosa cells via oxidative stress

BACKGROUND

Bisphenol A (BPA), an endocrine disrupting chemical with weak estrogenic and anti-androgenic activity, is widely present in various environmental media and organisms. It has certain reproductive toxicity and can cause a variety of female reproductive system diseases. Although BPA-stimulated apoptosis of granulosa cells has been widely elaborated, the effect of BPA on mouse pre-antral follicle granulosa cells (mpGCs) has not been well elucidated.

RESULTS

In this study, the results of live-dead cell staining showed that high concentrations of BPA severely impaired mpGCs growth viability and affected the cell cycle transition of mpGCs. We confirmed that BPA promotes the production of reactive oxygen species (ROS) and facilitates oxidative stress in mpGCs. In addition, immunofluorescence, transmission electron microscopy, and flow cytometry experiments demonstrated that BPA treatment for mpGCs resulted in apoptotic features, such as rounding, cytoplasmic crinkling, and mitochondrial damage. This was accompanied by a large production of ROS and apoptosis-inducing factor (AIF) translocation from the mitochondria to the nucleus. RNA-seq data showed that several apoptosis-related pathways were enriched in the high concentration BPA-treated group compared with the normal group, such as the p53 pathway, MAPK pathway, etc. CONCLUSIONS: These results suggest that cells undergo oxidative stress effects and apoptosis after BPA treatment for mpGCs, which affects normal follicle development. The potential mechanism of BPA-induced female reproductive toxicity was elucidated, while providing a research basis for the prevention and treatment of female reproductive diseases.

Gestational exposure to 1-NP induces ferroptosis in placental trophoblasts via CYP1B1/ERK signaling pathway leading to fetal growth restriction

Fetal growth restriction (FGR) is a prevalent complication in obstetrics, yet its exact aetiology remains unknown. Numerous studies suggest that the degradation of the living environment is a significant risk factor for FGR. 1-Nitropyrene (1-NP) is a widespread environmental pollutant as a representative substance of nitro-polycyclic aromatic hydrocarbons. In this study, we revealed that 1-NP induced FGR in fetal mice by constructing 1-NP exposed pregnant mice models. Intriguingly, we found that placental trophoblasts of 1-NP exposed mice exhibited significant ferroptosis, which was similarly detected in placental trophoblasts from human FGR patients. In this regard, we established a 1-NP exposed cell model in vitro using two human trophoblast cell lines, HTR8/SVneo and JEG-3. We found that 1-NP not only impaired the proliferation, migration, invasion and angiogenesis of trophoblasts, but also induced severe cellular ferroptosis. Meanwhile, the ferroptosis inhibitor ferrostatin-1 (Fer-1) effectively rescued 1-NP-induced trophoblast biological function impairment. Mechanistically, we revealed that 1-NP regulated ferroptosis by activating the ERK signaling pathway. Moreover, we innovatively revealed that CYP1B1 was essential for the activation of ERK signaling pathway induced by 1-NP. Overall, our study innovatively identified ferroptosis as a significant contributor to 1-NP induced trophoblastic functional impairment leading to FGR and clarified the specific mechanism by which 1-NP induced ferroptosis via the CYP1B1/ERK signaling pathway. Our study provided novel insights into the aetiology of FGR and revealed new mechanisms of reproductive toxicity of environmental pollutants.

Transcriptomic Integration Analyses Uncover Common Bisphenol A Effects Across Species and Tissues Primarily Mediated by Disruption of JUN/FOS, EGFR, ER, PPARG, and P53 Pathways

Bisphenol A (BPA) is a common endocrine disruptor widely used in the production of electronic, sports, and medical equipment, as well as consumer products like milk bottles, dental sealants, and thermal paper. Despite its widespread use, current assessments of BPA exposure risks remain limited due to the lack of comprehensive cross-species comparative analyses. To address this gap, we conducted a study aimed at identifying genes and fundamental molecular processes consistently affected by BPA in various species and tissues, employing an effective data integration method and bioinformatic analyses. Our findings revealed that exposure to BPA led to significant changes in processes like lipid metabolism, proliferation, and apoptosis in the tissues/cells of mammals, fish, and nematodes. These processes were found to be commonly affected in adipose, liver, mammary, uterus, testes, and ovary tissues. Additionally, through an in-depth analysis of signaling pathways influenced by BPA in different species and tissues, we observed that the JUN/FOS, EGFR, ER, PPARG, and P53 pathways, along with their downstream key transcription factors and kinases, were all impacted by BPA. Our study provides compelling evidence that BPA indeed induces similar toxic effects across different species and tissues. Furthermore, our investigation sheds light on the underlying molecular mechanisms responsible for these toxic effects. By uncovering these mechanisms, we gain valuable insights into the potential health implications associated with BPA exposure, highlighting the importance of comprehensive assessments and awareness of this widespread endocrine disruptor.

Bisphenol A exposure decreases sperm production and male fertility through inhibition PCBP2 expression

Growing evidence suggests that the exposure of bisphenol A (BPA), an endocrine disruptor that commonly present in the environment, can impair reproduction. However, conflicting results have been reported, and the underlying mechanism has not been fully understood. In this study, 3-week-old male mice were oral exposed to 50 mg/kg/d BPA or equivalent corn oil for 28 days. Their testis and epididymis were then collected for morphology examination by HE stains. The number of sperm was counted, and the morphology was analyzed by PNA (peptide nucleic acid) and pap staining. Fertilization capacity and successful rate were analyzed after mating with wide-type females. Spermatid DNA damage and apoptosis were evaluated by DFI, γH2AX stain, and TUNEL assay. RNA sequencing analysis was conducted to identify differentially expressed genes in testicular tissue of mice exposed to BPA. RNA interference was used to verify the regulatory mechanism of BPA exposure on gene expression in GC-2 cells. Our data showed that the total number of sperm was decreased and the morphology was impaired in BPA-exposed mice. In addition, the serum testosterone level and fertilization efficiency were also reduced. Mechanism studies showed that BPA could suppress the expression of PCBP2, a key regulatory gene in spermatid development, by activating the EZH2/H3K27me3. In conclusion, we found that BPA exposure can impair spermatid development via affecting key gene expression that is at least partially due to epigenetic modification.

An Overview of the Health Effects of Bisphenol A from a One Health Perspective

Bisphenol A (BPA) is a chemical compound, considered as an "emerging pollutant", that appears ubiquitously, contaminating the environment and food. It is an endocrine disruptor, found in a multitude of consumer products, as it is a constituent of polycarbonate used in the manufacture of plastics and epoxy resins. Many studies have evaluated the effects of BPA, using a wide range of doses and animal models. In this work, we carried out a review of relevant research related to the effects of BPA on health, through studies performed at different doses, in different animal models, and in human monitoring studies. Numerous effects of BPA on health have been described; in different animal species, it has been reported that it interferes with fertility in both females and males and causes alterations in their offspring, as well as being associated with an increase in hormone-dependent pathologies. Similarly, exposure to BPA has been related to other diseases of great relevance in public health such as obesity, hypertension, diabetes, or neurodevelopmental disorders. Its ubiquity and nonmonotonic behavior, triggering effects at exposure levels considered "safe", make it especially relevant when both animal and human populations are constantly and inadvertently exposed to this compound. Its effects at low exposure levels make it essential to establish safe exposure levels, and research into the effects of BPA must continue and be focused from a "One Health" perspective to take into account all the factors that could intervene in the development of a disease in any exposed organism.