Maternal serum bisphenol A levels and risk of pre-eclampsia: a nested case-control study

Exposure to Bisphenol A jeopardizes decidualization and consequently triggers preeclampsia by up-regulating CYP1B1

Preeclampsia (PE) is a pregnancy-related disease that poses a significant threat to the health of both the mother and the fetus. Previous studies have primarily focused on the role of the placenta in PE pathogenesis; however, normal decidualization is crucial for the subsequent development of the placenta and pregnancy. Bisphenol A (BPA) is an environmental endocrine disruptor commonly used in the synthesis of polycarbonate and epoxy resins. Overexposure to BPA can result in severe reproductive issues. To further investigate the effects of BPA exposure on pregnancy, C57BL/6 mice were continuously exposed to either 0 or 100 mg/kg of BPA in this study. As a result, these mice developed symptoms of hypertension and proteinuria, indicative of PE. Additionally, their decidualization process was impaired. Transcriptome sequencing of artificially induced decidua revealed a significant upregulation in the expression of CYP1B1 within the BPA-treated group. This upregulation accelerated the metabolism of estrogen and progesterone, leading to significant decreases in their levels. Furthermore, the expression levels of estrogen and progesterone receptors and their responding genes were significantly reduced. These findings suggest that BPA exposure can negatively impact decidualization and placental development, potentially contributing to the development of PE.

The ENDOMIX perspective: how everyday chemical mixtures impact human health and reproduction by targeting the immune system†

Endocrine-disrupting chemicals are natural and synthetic compounds found ubiquitously in the environment that interfere with the hormonal-immune axis, potentially impacting human health and reproduction. Exposure to endocrine-disrupting chemicals has been associated with numerous health risks, such as neurodevelopmental disorders, metabolic syndrome, thyroid dysfunction, infertility, and cancers. Nevertheless, the current approach to establishing causality between these substances and disease outcomes has limitations. Epidemiological and experimental research on endocrine-disrupting chemicals faces challenges in accurately assessing chemical exposure and interpreting non-monotonic dose response curves. In addition, most studies have focused on single chemicals or simple mixtures, overlooking complex real-life exposures and mechanistic insights, in particular regarding endocrine-disrupting chemicals' impact on the immune system. The ENDOMIX project, funded by the EU's Horizon Health Program, addresses these challenges by integrating epidemiological, risk assessment, and immunotoxicology methodologies. This systemic approach comprises the triangulation of human cohort, in vitro, and in vivo data to determine the combined effects of chemical mixtures. The present review presents and discusses current literature regarding human reproduction in the context of immunotolerance and chemical disruption mode of action. It further underscores the ENDOMIX perspective to elucidate the impact of endocrine-disrupting chemicals on immune-reproductive health.

The Effect of Bisphenol and Its Cytotoxicity on Female Infertility and Pregnancy Outcomes: A Narrative Review

Bisphenols, particularly bisphenol A (BPA), are among the most thoroughly investigated endocrine disrupting chemicals (EDCs). BPA was the first synthetic estrogen to be identified, exerting its estrogenic effects through interaction with human estrogen receptors (ERs). The aim of the present narrative review is to summarize the most recent literature regarding the adverse effects of bisphenols on female fertility and pregnancy outcomes. A review of the literature in the PubMed/Medline and Scopus databases was conducted in November 2024 and 15 studies were included in the present review. BPA levels were higher in women with diminished ovarian reserve, polycystic ovary syndrome, and recurrent miscarriages. Furthermore, one study showed a significant association between BPA levels and the onset of gestational diabetes mellitus. Higher levels of BPA are associated with disruptions to the female reproductive system, such as ovarian function, reduced number of antral follicles, and lower anti-Müllerian hormone (AMH) levels. Bisphenols A and S were associated with an increased risk of developing gestational diabetes mellitus. Bisphenols A and F were correlated with an increased risk of lower birth weight and bisphenol F seemed to be associated with an increased risk of preterm delivery. Ultimately, further research is necessary to fully understand the extent of the harmful effects that bisphenols have separately and as mixtures on the female reproductive system.

Association of Phenols, Parabens, and Their Mixture with Maternal Blood Pressure Measurements in the PROTECT Cohort

BACKGROUND

Phenols and parabens are two classes of high production volume chemicals that are used widely in consumer and personal care products and have been associated with reproductive harm and pregnancy complications, such as preeclampsia and gestational diabetes. However, studies examining their influence on maternal blood pressure and gestational hypertension are limited.

OBJECTIVES

We investigated associations between individual phenols, parabens, and their mixture on maternal blood pressure measurements, including systolic and diastolic blood pressure (SBP and DBP) and hypertension during pregnancy (defined as stage 1 or 2 hypertension), among N = 1,433 Puerto Rico PROTECT study participants.

METHODS

We examined these relationships cross-sectionally at two time points during pregnancy (16-20 and 24-28 wks gestation) and longitudinally using linear mixed models (LMMs). Finally, we used quantile g-computation to examine the mixture effect on continuous (SBP, DBP) and binary (hypertension during pregnancy) blood pressure outcomes.

RESULTS

We observed a trend of higher odds of hypertension during pregnancy with exposure to multiple analytes and the overall mixture [including bisphenol A (BPA), bisphenol S (BPS), triclocarbon (TCC), triclosan (TCS), benzophenone-3 (BP-3), 2,4-dichlorophenol (2,4-DCP), 2,5-dichlorophenol (2,5-DCP), methyl paraben (M-PB), propyl paraben (P-PB), butyl paraben (B-PB), and ethyl paraben (E-PB)], especially at 24-28 wk gestation, with an adjusted mixture odds ratio ( OR ) = 1.57 (95% CI: 1.03, 2.38). Lower SBP and higher DBP were also associated with individual analytes, with results from LMMs most consistent for methyl paraben (M-PB) or propyl paraben (P-PB) and increased DBP across pregnancy [adjusted M-PB β = 0.78 (95% CI: 0.17, 1.38) and adjusted P-PB β = 0.85 (95% CI: 0.19, 1.51)] and for BPA, which was associated with decreased SBP (adjusted β = - 0.57 ; 95% CI: - 1.09 , - 0.05 ). Consistent with other literature, we also found evidence of effect modification by fetal sex, with a strong inverse association observed between the overall exposure mixture and SBP at visit 1 among participants carrying female fetuses only.

CONCLUSIONS

Our findings indicate that phenol and paraben exposure may collectively increase the risk of stage 1 or 2 hypertension during pregnancy, which has important implications for fetal and maternal health. https://doi.org/10.1289/EHP14008.

Bisphenol A-What Do We Know? A Global or Local Approach at the Public Health Risk Level

BPA has demonstrated enormous multisystem and multi-organ toxicity shown mainly in animal models. Meanwhile, the effects of its exposure in humans still require years of observation, research, and answers to many questions. Even minimal and short-term exposure contributes to disorders or various types of dysfunction. It is released directly or indirectly into the environment at every stage of the product life cycle, demonstrating its ease of penetration into the body. The ubiquity and general prevalence of BPA influenced the main objective of the study, which was to assess the toxicity and health effects of BPA and its derivatives based on the available literature. In addition, the guidelines of various international institutions or regions of the world in terms of its reduction in individual products were checked. Bisphenol A is the most widely known chemical and perhaps even the most studied by virtually all international or national organizations, but nonetheless, it is still controversial. In general, the level of BPA biomonitoring is still too high and poses a potential threat to public health. It is beginning to be widely argued that future toxicity studies should focus on molecular biology and the assessment of human exposure to BPA, as well as its substitutes. The effects of its exposure still require years of observation, extensive research, and answers to many questions. It is necessary to continue to deepen the knowledge and interest of many organizations, companies, and consumers around the world in order to make rational purchases as well as future choices, not only consumer ones.

Distribution and potential risk factors of bisphenol a in serum and urine among Chinese from 2004 to 2019

Background

Bisphenol A (BPA) is an oil-derived, large-market volume chemical with endocrine disrupting properties and reproductive toxicity. Moreover, BPA is frequently used in food contact materials, has been extensively researched recently, and widespread exposure in the general population has been reported worldwide. However, national information on BPA levels in general Chinese people is lacking.

Methods

This study collected and analyzed 145 (104 in urine and 41 in serum) research articles published between 2004 and 2021 to reflect the BPA internal exposure levels in Chinese populations. The Monte Carlo simulation method is employed to analyze and estimate the data in order to rectify the deviation caused by a skewed distribution.

Results

Data on BPA concentrations in urine and serum were collected from 2006 to 2019 and 2004 to 2019, respectively. Urinary BPA concentrations did not vary significantly until 2017, with the highest concentration occurring from 2018 to 2019 (2.90 ng/mL). The serum BPA concentration decreased to the nadir of 1.07 ng/mL in 2011 and gradually increased to 2.54 ng/mL. Nationally, 18 provinces were studied, with Guangdong (3.50 ng/mL), Zhejiang (2.57 ng/mL), and Fujian (2.15 ng/mL) having the highest urine BPA levels. Serum BPA was investigated in 15 provinces; Jiangsu (9.14 ng/mL) and Shandong (5.80 ng/mL) were relatively high. The results also indicated that males' urine and serum BPA levels were higher than females, while the BPA levels in children were also higher than in adults (p < 0.001). Furthermore, the volume of garbage disposal (r = 0.39, p < 0.05), household sewage (r = 0.34, p < 0.05), and waste incineration content (r = 0.35, p < 0.05) exhibited a strong positive connection with urine BPA levels in Chinese individuals.

Conclusion

Despite using a data consolidation approach, our study found that the Chinese population was exposed to significant amounts of BPA, and males having a higher level than females. Besides, the levels of BPA exposure are influenced by the volume of garbage disposal, household sewage, and waste incineration content.

Bisphenol A contamination in aquatic environments: a review of sources, environmental concerns, and microbial remediation

The production of polycarbonate, a high-performance transparent plastic, employs bisphenol A, which is a prominent endocrine-disrupting compound. Polycarbonates are frequently used in the manufacturing of food, bottles, storage containers for newborns, and beverage packaging materials. Global production of BPA in 2022 was estimated to be in the region of 10 million tonnes. About 65-70% of all bisphenol A is used to make polycarbonate plastics. Bisphenol A leaches from improperly disposed plastic items and enters the environment through wastewater from plastic-producing industries, contaminating, sediments, surface water, and ground water. The concentration BPA in industrial and domestic wastewater ranges from 16 to 1465 ng/L while in surface water it has been detected 170-3113 ng/L. Wastewater treatment can be highly effective at removing BPA, giving reductions of 91-98%. Regardless, the remaining 2-9% of BPA will continue through to the environment, with low levels of BPA commonly observed in surface water and sediment in the USA and Europe. The health effects of BPA have been the subject of prolonged public and scientific debate, with PubMed listing more than 17,000 scientific papers as of 2023. Bisphenol A poses environmental and health hazards in aquatic systems, affecting ecosystems and human health. While several studies have revealed its presence in aqueous streams, environmentally sound technologies should be explored for its removal from the contaminated environment. Concern is mostly related to its estrogen-like activity, although it can interact with other receptor systems as an endocrine-disrupting chemical. Present review article encompasses the updated information on sources, environmental concerns, and sustainable remediation techniques for bisphenol A removal from aquatic ecosystems, discussing gaps, constraints, and future research requirements.

Effects of Xenobiotic Compounds on Preeclampsia and Potential Mechanisms

Preeclampsia (PE) refers to a disease with new hypertension and albuminuria or other end-organ damage after 20 weeks of pregnancy. As a major complication of pregnancy, PE can increase the morbidity and mortality of pregnant women and fetuses and cause serious social burden. Recently, it has been found that exposure to xenobiotic compounds, especially endocrine disruptors in the environment, may contribute to the development of PE. However, the underlying mechanism is still unclear. It is generally believed that PE is related to placental dysplasia, spiral artery remodelling failure, oxidative stress, etc. Therefore, in order to better prevent the occurrence of PE and reduce the damage and impact on mother and fetus, this paper reviews the role and potential mechanism of PE induced by exogenous chemicals and provides an outlook on the environmental etiology of PE.

Re-evaluation of the risks to public health related to the presence of bisphenol A (BPA) in foodstuffs

In 2015, EFSA established a temporary tolerable daily intake (t-TDI) for BPA of 4 μg/kg body weight (bw) per day. In 2016, the European Commission mandated EFSA to re-evaluate the risks to public health from the presence of BPA in foodstuffs and to establish a tolerable daily intake (TDI). For this re-evaluation, a pre-established protocol was used that had undergone public consultation. The CEP Panel concluded that it is Unlikely to Very Unlikely that BPA presents a genotoxic hazard through a direct mechanism. Taking into consideration the evidence from animal data and support from human observational studies, the immune system was identified as most sensitive to BPA exposure. An effect on Th17 cells in mice was identified as the critical effect; these cells are pivotal in cellular immune mechanisms and involved in the development of inflammatory conditions, including autoimmunity and lung inflammation. A reference point (RP) of 8.2 ng/kg bw per day, expressed as human equivalent dose, was identified for the critical effect. Uncertainty analysis assessed a probability of 57-73% that the lowest estimated Benchmark Dose (BMD) for other health effects was below the RP based on Th17 cells. In view of this, the CEP Panel judged that an additional uncertainty factor (UF) of 2 was needed for establishing the TDI. Applying an overall UF of 50 to the RP, a TDI of 0.2 ng BPA/kg bw per day was established. Comparison of this TDI with the dietary exposure estimates from the 2015 EFSA opinion showed that both the mean and the 95th percentile dietary exposures in all age groups exceeded the TDI by two to three orders of magnitude. Even considering the uncertainty in the exposure assessment, the exceedance being so large, the CEP Panel concluded that there is a health concern from dietary BPA exposure.

Exposure to endocrine-disrupting chemicals and risk of gestational hypertension and preeclampsia: A systematic review and meta-analysis

Prenatal exposure to endocrine-disrupting chemicals has been linked to gestational hypertension (GH) and preeclampsia (PE). However, the results were conflicting and inconclusive. We conducted a systematic review and meta-analysis for an overview of these relationships. We searched PubMed, and Google Scholar for studies investigating bisphenol A, phthalates, and per or poly-fluoroalkyl substances and GH or PE. Pooled odds ratio (OR) with a 95% confidence interval (CI) were calculated for risk estimate using the generic inverse variance method. A total of 14 studies were included in the present analysis. The pooled results demonstrated that perfluorooctanoic acid (PFOA, OR:1.20, 95% CI: 1.04, 1.39), perfluoro octane sulfonic acid (PFOS, (OR:1.23, 95% CI: 1.10, 1.38), and perfluononanoic acid (PFNA, OR:1.20, 95% CI: 1.03, 1.40) were significantly associated with an increased risk of PE. There was no significant association observed with perfluoro hexane sulfonic acid (PFHxS), perfluoro decanoic acid (PFDA), perfluoro heptanoic acid (PFHpA), and perfluoro undecanoic acid (PFUnDA) and PE. For GH, a statistically significant positive association was found with PFOA (OR:1.18, 95% CI: 1.01, 1.39) and PFHxS (OR:1.15, 95% CI: 1.02, 1.29). Among various phthalates analysed only mono-ethyl phthalate (MEP, OR:1.37, 95% CI: 1.11, 1.70) showed an association with GH. From our analysis, bisphenol A exposure during pregnancy did not show a significant association with the risk of PE. Our findings indicated that exposure to PFASs such as PFOA, PFOS, and PFNA during pregnancy is associated with an increased risk of PE and PFOA and PFHxS with GH. We also found that MEP was associated with GH. Most of the results were unstable in sensitivity analysis. Since most of these associations have limited evidence, more research is needed to confirm these findings.

Prediction of pregnancy-related hypertensive disorders using metabolomics: a systematic review

OBJECTIVE

To determine the accuracy of metabolomics in predicting hypertensive disorders in pregnancy.

DESIGN

Systematic review of observational studies.

DATA SOURCES AND STUDY ELIGIBILITY CRITERIA

An electronic literature search was performed in June 2019 and February 2022. Two researchers independently selected studies published between 1998 and 2022 on metabolomic techniques applied to predict the condition; subsequently, they extracted data and performed quality assessment. Discrepancies were dealt with a third reviewer. The primary outcome was pre-eclampsia. Cohort or case-control studies were eligible when maternal samples were taken before diagnosis of the hypertensive disorder.

STUDY APPRAISAL AND SYNTHESIS METHODS

Data on study design, maternal characteristics, how hypertension was diagnosed, metabolomics details and metabolites, and accuracy were independently extracted by two authors.

RESULTS

Among 4613 initially identified studies on metabolomics, 68 were read in full text and 32 articles were included. Studies were excluded due to duplicated data, study design or lack of identification of metabolites. Metabolomics was applied mainly in the second trimester; the most common technique was liquid-chromatography coupled to mass spectrometry. Among the 122 different metabolites found, there were 23 amino acids and 21 fatty acids. Most of the metabolites were involved with ammonia recycling; amino acid metabolism; arachidonic acid metabolism; lipid transport, metabolism and peroxidation; fatty acid metabolism; cell signalling; galactose metabolism; nucleotide sugars metabolism; lactose degradation; and glycerolipid metabolism. Only citrate was a common metabolite for prediction of early-onset and late-onset pre-eclampsia. Vitamin D was the only metabolite in common for pre-eclampsia and gestational hypertension prediction. Meta-analysis was not performed due to lack of appropriate standardised data.

CONCLUSIONS AND IMPLICATIONS

Metabolite signatures may contribute to further insights into the pathogenesis of pre-eclampsia and support screening tests. Nevertheless, it is mandatory to validate such methods in larger studies with a heterogeneous population to ascertain the potential for their use in clinical practice.

PROSPERO REGISTRATION NUMBER

CRD42018097409.

The hazardous threat of Bisphenol A: Toxicity, detection and remediation

Bisphenol A (or BPA) is a toxic endocrine disrupting chemical that is released into the environment through modern manufacturing practices. BPA can disrupt the production, function and activity of endogenous hormones causing irregularity in the hypothalamus-pituitary-gonadal glands and also the pituitary-adrenal function. BPA has immuno-suppression activity and can downregulate T cells and antioxidant genes. The genotoxicity and cytotoxicity of BPA is paramount and therefore, there is an immediate need to properly detect and remediate its influence. In this review, we discuss the toxic effects of BPA on different metabolic systems in the human body, followed by its mechanism of action. Various novel detection techniques (LC-MS, GC-MS, capillary electrophoresis, immunoassay and sensors) involving a pretreatment step (liquid-liquid microextraction and molecularly imprinted solid-phase extraction) have also been detailed. Mechanisms of various remediation strategies, including biodegradation using native enzymes, membrane separation processes, photocatalytic oxidation, use of nanosorbents and thermal degradation has been detailed. An overview of the global regulations pertaining to BPA has been presented. More investigations are required on the efficiency of integrated remediation technologies rather than standalone methods for BPA removal. The effect of processing operations on BPA in food matrices is also warranted to restrict its transport into food products.

Fetoplacental vasculature as a model to study human cardiovascular endocrine disruption

Increasing evidence has associated the exposure of endocrine-disrupting chemicals (EDCs) with the cardiovascular (CV) system. This exposure is particularly problematic in a sensitive window of development, pregnancy. Pregnancy exposome can affect the overall health of the pregnancy by dramatic changes in vascular physiology and endocrine activity, increasing maternal susceptibility. Moreover, fetoplacental vascular function is generally altered, increasing the risk of developing pregnancy complications (including cardiovascular diseases, CVD) and predisposing the foetus to adverse health risks later in life. Thus, our review summarizes the existing literature on exposures to EDCs during pregnancy and adverse maternal health outcomes, focusing on the human placenta, vein, and umbilical artery associated with pregnancy complications. The purpose of this review is to highlight the role of fetoplacental vasculature as a model for the study of human cardiovascular endocrine disruption. Therefore, we emphasize that the placenta, together with the umbilical arteries and veins, allows a better characterization of the pregnant woman's exposome. Consequently, it contributes to the protection of the mother and foetus against CV disorders in life.

Exposure to endocrine disrupting chemicals (EDCs) and cardiometabolic indices during pregnancy: The HOME Study

BACKGROUND

Toxicology studies have identified pregnancy as a window of susceptibility for endocrine disrupting chemicals (EDCs) and cardiometabolic indices in women. No study in humans, however, has examined EDC mixtures and cardiometabolic indices during pregnancy.

METHODS

We used the Health Outcomes and Measures of the Environment (HOME) Study to examine whether bisphenol A (BPA), polybrominated diphenyl ethers (PBDEs), per- and polyfluoroalkyl substances (PFAS), and phthalates are associated with blood pressure, glucose, and lipids in 388 pregnant women. We measured PBDEs and PFAS in serum at 16 weeks gestation, while BPA and phthalate metabolites were quantified in urine at 16 and 26 weeks gestation. We used linear regression and Bayesian Kernel Machine Regression (BKMR) to estimate covariate-adjusted associations of individual EDCs and their mixtures with cardiometabolic indices during pregnancy.

RESULTS

A 10-fold increase in BDE-28 was associated with a 13.1 mg/dL increase in glucose (95% Confidence Interval [CI] 2.9, 23.2) in linear regression. The BKMR model also identified BDE-28 as having a positive association with glucose. BDE-28, BDE-47, and BDE-99 were positively associated with total cholesterol in both single- and multi-pollutant models, whereas a suggestive negative association was noted with BDE-153. Mono-n-butyl phthalate (MBP) (β = -7.9 mg/dL, 95% CI -12.9, -3.0) and monobenzyl phthalate (MBzP) (β = -6.3 mg/dL, 95% CI -10.6, -2.0) were both associated with significant decreases in cholesterol in linear regression, but only MBzP was identified as an important contributor in the BKMR model.

CONCLUSION

Overall, we observed positive associations between PBDEs with glucose and cholesterol levels during pregnancy, while negative associations were found between some phthalate biomarkers and cholesterol. No relationship was noted for BPA or PFAS with cardiometabolic indices during pregnancy across both models.

REPRODUCTIVE TOXICOLOGY: Pregnancy exposure to endocrine disrupting chemicals: implications for women's health

Women are ubiquitously exposed to non-persistent endocrine disrupting chemicals (EDCs) from food contact materials and personal care products. Understanding the impacts of exposure to these chemicals on pregnancy and long-term health outcomes in women is a critical area of research that has been largely overlooked. This brief review focuses on the epidemiologic literature exploring associations of non-persistent EDCs - including phthalates, parabens, bisphenols, and triclosan - with maternal pregnancy outcomes and long-term health outcomes in women. We focus on the challenges of this research, particularly assessing non-persistent EDC exposures, aspects of study design, and statistical approaches. We conclude by reviewing the best practices for non-persistent EDC research with regards to pregnancy and women's health. Though limited, we found some evidence indicating that exposure to non-persistent EDCs is associated with pregnancy health. However, findings from these studies have been inconsistent and require corroboration. Recent studies have also proposed that non-persistent EDC exposures in pregnancy may adversely affect postnatal maternal health. To date, only a few studies have been conducted and have only focused on postpartum weight. More research is needed in this area to inform efforts to promote optimal health across the lifespan of women.

Endocrine-Disrupting Chemical Exposures in Pregnancy: a Sensitive Window for Later-Life Cardiometabolic Health in Women

Purpose of Review

Pregnancy can be seen as a “stress test” with complications predicting later-life cardiovascular disease risk. Here, we review the growing epidemiological literature evaluating environmental endocrine-disrupting chemical (EDC) exposure in pregnancy in relation to two important cardiovascular disease risk factors, hypertensive disorders of pregnancy and maternal obesity.

Recent Findings

Overall, evidence of EDC-maternal cardiometabolic associations was mixed. The most consistent associations were observed for phenols and maternal obesity, as well as for perfluoroalkyl substances (PFASs) with hypertensive disorders. Research on polybrominated flame retardants and maternal cardiometabolic outcomes is limited, but suggestive.

Summary

Although numerous studies evaluated pregnancy outcomes, few evaluated the postpartum period or assessed chemical mixtures. Overall, there is a need to better understand whether pregnancy exposure to these chemicals could contribute to adverse cardiometabolic health outcomes in women, particularly given that cardiovascular disease is the leading cause of death in women.

Bisphenol A: A potential Toll-like receptor 4/myeloid differentiation factor 2 complex agonist

In addition to endocrine disruption, bisphenol A (BPA) is known to induce inflammation through the activation of nuclear factor-κB (NF-κB). However, detailed studies on the mechanism of NF-κB activation by BPA have not been sufficiently conducted. In the present study, we observed that low concentrations of BPA (≤1 μM) upregulated the release of proinflammatory mediators, including nitric oxide (NO) and prostaglandin E₂ (PGE₂), as well as proinflammatory cytokines, including tumor necrosis factor (TNF)-α, interleukin (IL)-12, and IL-6. Molecular modeling predicted that BPA docked with the Toll-like receptor 4 (TLR4)/myeloid differentiation factor 2 (MD2) complex activates downstream molecules including myeloid differentiation primary response 88 (MyD88) and IL-1 receptor-associated kinase 4 (IRAK-4) and results in the upregulation of the NF-κB signaling pathway. Additionally, BPA increased morphological abnormalities and mortality in zebrafish larvae and enhanced the dispersal of macrophages and neutrophils in the whole body, thereby causing an endotoxemia-like disorder. However, a specific TLR4 inhibitor, TLR4-IN-C34, mitigated BPA-induced mortality and morphological abnormalities, which indicates that the TLR4/MD2 complex is a molecular target of BPA-induced immunotoxicity. Collectively, our results indicate that low concentrations of BPA, which is a potential agonist of the TLR4/MD2 complex, can intensify the immune response and eventually cause an endotoxemia-like disorder.

Predictive value of 4-Hydroxyglutamate and miR-149-5p on eclampsia

This research aimed at exploring the predictive value of 4-Hydroxyglutamate and miR-149-5p on eclampsia. Preeclampsia patients admitted to our hospital (n = 204), with 112 mild patients and 92 severe patients. Thereinto, pregnant women who underwent physical examination were regarded as a normal group (NG) (n = 100). Serum 4-Hydroxyglutamate levels and miR-149-5p in each group were detected. The serum 4-Hydroxyglutamate level in pregnant women in the NG was markedly lower than that in preeclampsia, while the miR-149-5p level was higher (p = 0.001). The serum 4-Hydroxyglutamate level in severe preeclampsia was higher than that in mild preeclampsia, while the miR-149-5p level was lower (p = 0.001). Partial thromboplastin time (APTT) and prothrombin time (PT) of preeclampsia patients were lower than those of the NG, while Fibrinogen (Fib) was higher (p = 0.001). With the aggravation of the condition of patients, PT, APTT decreased and Fib index increased. In preeclampsia patients, serum 4-Hydroxyglutamate was negatively correlated with PT and APTT, positively correlated with Fib content (p < 0.001); serum miR-149-5p was dramatically positively correlated with PT and APTT, negatively correlated with Fib content (p < 0.001). 4-Hydroxyglutamate and miR-149-5p were relevant to the occurrence time of preeclampsia; 4-Hydroxyglutamate, miR-149-5p and their combination could be used for preeclampsia diagnosis. According to the situation of newborn, they were divided into good and poor groups. The 4-Hydroxyglutamate level in the good group was lower than that in the poor group, while the miR-149-5p level was higher. The adverse prognosis of preeclampsia patients was predicted by 4-Hydroxyglutamate and miR-149-5p. 4-Hydroxyglutamate is highly expressed in preeclampsia, while miR-149-5p is low. Single and combined detection of 4-Hydroxyglutamate, miR-149-5p can be used for preeclampsia diagnosis and prediction.

Placental microRNAs: Responders to environmental chemicals and mediators of pathophysiology of the human placenta

MicroRNAs (miRNAs) are epigenetic modifiers that play an important role in the regulation of the expression of genes across the genome. miRNAs are expressed in the placenta as well as other organs, and are involved in several biological processes including the regulation of trophoblast differentiation, migration, invasion, proliferation, apoptosis, angiogenesis and cellular metabolism. Related to their role in disease process, miRNAs have been shown to be differentially expressed between normal placentas and placentas obtained from women with pregnancy/health complications such as preeclampsia, gestational diabetes mellitus, and obesity. This dysregulation indicates that miRNAs in the placenta likely play important roles in the pathogenesis of diseases during pregnancy. Furthermore, miRNAs in the placenta are susceptible to altered expression in relation to exposure to environmental toxicants. With relevance to the placenta, the dysregulation of miRNAs in both placenta and blood has been associated with maternal exposures to several toxicants. In this review, we provide a summary of miRNAs that have been assessed in the context of human pregnancy-related diseases and in relation to exposure to environmental toxicants in the placenta. Where data are available, miRNAs are discussed in their context as biomarkers of exposure and/or disease, with comparisons made across-tissue types, and conservation across studies detailed.

Effects of Bisphenol A on expression of genes related to amino acid transporters, insulin- like growth factor, aquaporin and amino acid release by porcine trophectoderm cells

The peri-implantation period of pregnancy is critical for conceptus development, implantation, and signaling for establishment of pregnancy. This study evaluated the effects of bisphenol A (BPA) on proliferation, adhesion, and migration of porcine trophectoderm (pTr2) cells, expression of transporters of arginine and synthesis of amino acids. All concentrations of BPA decreased proliferation and adhesion of pTr2 cells after 96 h compared to the control group. Lower concentrations of BPA (1 × 10^-9, 1 × 10^-8, 10^-7M) increased (P < 0.05), but higher concentrations of BPA (1 × 10^-5, 1 × 10^-4 M) decreased migration of pTr2 cells. BPA increased expression of SLC7A1 mRNA at lower concentrations (1 × 10^-9 to 1 × 10^-6M) and SL7A6, another cationic acid transporter, at higher concentrations (1 × 10^-5, 1 × 10^-4 M). BPA also down-regulated the expression of IGF1 and IGF1 receptor at concentrations of 1 × 10^-7 to 1 × 10^-4 M compared to the control group. The expression of mRNAs for aquaporins (AQP) 3 and 4 were reduced at all concentrations of BPA, but at lower concentrations of BPA, (1 × 10^-9 to 1 × 10^-8M) expression of AQP9 mRNA increased and the expression of AQP11 was not affected by BPA (P > 0.05). There was an inhibitory effect of BPA on the release of synthesis of asparagine, threonine, taurine, tryptophan, and ornithine into the culture medium by pTr2 cells. Collectively, BPA adversely affected the expression of transporters for cationic amino acids like arginine, as well as AQPs, IGF1, and IGF1R associated with proliferation, migration, and adhesion of pTr2 cells. Those adverse effects would likely increase pregnancy losses during the peri-implantation period of pregnancy.

Association of exposure to prenatal phthalate esters and bisphenol A and polymorphisms in the ESR1 gene with the second to fourth digit ratio in school-aged children: Data from the Hokkaido study

Phthalates and bisphenol A (BPA) are estrogenic endocrine disruptors. Polymorphisms in the gene encoding estrogen receptor 1 (ESR1) may contribute to the ratio of the lengths of the second and fourth digits (2D:4D), which is considered an index of prenatal exposure to sex hormones. Thus, we investigated whether ESR1 polymorphisms modify the effects of prenatal exposure to phthalates and BPA on 2D:4D in a birth cohort. Maternal serum in the first trimester was used to determine prenatal exposure to these compounds. Six hundred twenty-three children (7 years of age) provided mean 2D:4D from photocopies and were genotyped for single nucleotide polymorphisms in ESR1, particularly PvuII (T > C, dbSNP: rs2234693), XbaI (A > G, dbSNP: rs9340799), and rs2077647 (A > G). The associations among compound exposure, mean 2D:4D, and ESR1 polymorphisms were assessed by multiple linear regression adjusted for potential cofounding factors. Boys with the AG/GG genotype at rs2077647 in the group exposed to high levels of mono(2-ethylhexyl) phthalate (MEHP) or Σ Di(2-ethylhexyl) phthalate (DEHP) showed feminized 2D:4D compared with boys with the AA genotype at rs2077647 who had low exposure to MEHP or ΣDEHP (MEHP: increase in mean 2D:4D of 1.51%, 95% confidence interval [CI]: 0.40-2.63; ΣDEHP: increase in mean 2D:4D of 1.37%, 95% CI: 0.25-2.49). No significant differences were found among girls. There were no associations between mean 2D:4D and metabolites other than MEHP or BPA. These data suggest that ESR1 polymorphisms modify the effects of prenatal exposure to DEHP on mean 2D:4D among boys.

Bisphenol-A in the European Prospective Investigation into Cancer and Nutrition cohort in Spain: Levels at recruitment and associated dietary factors

Bisphenol A (BPA) is considered an endocrine disruptor and it is present in numerous products of daily use. The aim of this study was to analyze serum BPA concentrations in a subcohort of the Spanish European Prospective Investigation into Cancer and Nutrition (EPIC), as well as to identify potential predictors of the exposure. The population consisted on 3553 subjects from 4 EPIC-Spain centres and BPA levels were measured in serum samples by UHPLC-MS/MS. Almost 70% of the participants showed detectable BPA values (>0.2 ng/ml), with a geometric mean of 1.19 ng/ml (95% CI: 1.12-1.25). By sex, detectable percentages were similar (p = 0.56) but with higher serum levels in men (1.27 vs 1.11 ng/ml, p = 0.01). Based on the adjusted regression models, a 50 g/day increase in the consumption of added fats and oils were associated with 43% lower BPA serum levels, while sugar and confectionary was associated with 25% higher levels of serum BPA. We evidenced differential exposure levels by province, sex and age, but not by anthropometric or lifestyle characteristics. Further investigation is needed to understand the influence of diet in BPA exposure.

Concentrations of bisphenol A and its alternatives in paired maternal-fetal urine, serum and amniotic fluid from an e-waste dismantling area in China

Bisphenol A (BPA) and its alternatives are suspected endocrine disruptors. However, prenatal exposure and transplacental transfer of bisphenols (BPs is still limited. Therefore, BPA and its six alternatives in maternal serum (MS), maternal urine (MU), cord serum (CS), and amniotic fluid (AF) samples collected from 106 maternal-fetal pairs in an e-waste dismantling site in Southern China were determined. Bisphenol AF (BPAF) and bisphenol S (BPS) were the dominant BPA alternatives observed in MS and CS, and the geometric mean (GM) concentration of BPAF (0.013 ng/mL in MS, 0.097 ng/mL in CS) and BPS (0.01 ng/mL in MS, 0.03 ng/mL in CS) in MS and CS was lower than that of BPA (0.5 ng/mL in MS, 1.2 ng/mL in CS). The ratios of BPA concentrations between MU and MS (MU:MS ratio) were over three times higher than those of AF and CS (AF:CS ratio), thereby suggesting low biotransformation/metabolism of BPA in fetuses. The placental transfer rates of BPs (i.e., CS:MS ratio) were compound-specific (BPAF 3.26, BPA 1.94, BPS 1.11). Results suggest that BPA and its alternatives can pass through the placental barrier. The placental transfer rates of BPs are positively related to molecular weight or log K_ow values. This finding indicates that an active transport is responsible for the placental transfer of BPs.

Heightened susceptibility: A review of how pregnancy and chemical exposures influence maternal health

Pregnancy is a unique period when biological changes can increase sensitivity to chemical exposures. Pregnant women are exposed to multiple environmental chemicals via air, food, water, and consumer products, including flame retardants, plasticizers, and pesticides. Lead exposure increases risk of pregnancy-induced hypertensive disorders, although women's health risks are poorly characterized for most chemicals. Research on prenatal exposures has focused on fetal outcomes and less on maternal outcomes. We reviewed epidemiologic literature on chemical exposures during pregnancy and three maternal outcomes: preeclampsia, gestational diabetes, and breast cancer. We found that pregnancy can heighten susceptibility to environmental chemicals and women's health risks, although variations in study design and exposure assessment limited study comparability. Future research should include pregnancy as a critical period for women's health. Incorporating biomarkers of exposure and effect, deliberate timing and method of measurement, and consistent adjustment of potential confounders would strengthen research on the exposome and women's health.

Oestrogenic Endocrine Disruptors in the Placenta and the Fetus

Endocrine disrupting chemicals (EDCs) are exogenous substances that interfere with the stability and regulation of the endocrine system of the body or its offspring. These substances are generally stable in chemical properties, not easy to be biodegraded, and can be enriched in organisms. In the past half century, EDCs have gradually entered the food chain, and these substances have been frequently found in maternal blood. Perinatal maternal hormone levels are unstable and vulnerable to EDCs. Some EDCs can affect embryonic development through the blood-fetal barrier and cause damage to the neuroendocrine system, liver function, and genital development. Some also effect cross-generational inheritance through epigenetic mechanisms. This article mainly elaborates the mechanism and detection methods of estrogenic endocrine disruptors, such as bisphenol A (BPA), organochlorine pesticides (OCPs), diethylstilbestrol (DES) and phthalates (PAEs), and their effects on placenta and fetal health in order to raise concerns about the proper use of products containing EDCs during pregnancy and provide a reference for human health.

The role of epigenetic changes in preeclampsia

Preeclampsia (PE) is a disorder affecting 2-10% of pregnancies and has a major role for perinatal and maternal mortality and morbidity. PE can be occurred by initiation of new hypertension combined with proteinuria after 20 weeks gestation, as well as various reasons such as inflammatory cytokines, poor trophoblast invasion can be related with PE disease. Environmental factors can cause epigenetic changes including DNA methylation, microRNAs (miRNAs), and histone modification that may be related to different diseases such as PE. Abnormal DNA methylation during placentation is the most important epigenetic factor correlated with PE. Moreover, changes in histone modification like acetylation and also the effect of overregulation or low regulation of miRNAs or long noncoding RNAs on variety signaling pathways can be resulted in PE. The aim of this review is to describe of studies about epigenetic changes in PE and its therapeutic strategies.

The adverse health effects of bisphenol A and related toxicity mechanisms

Bisphenol A (BPA) is an industrial component commonly used in synthesis of polycarbonate plastics, epoxy resin and other polymer materials. Due to its mass productions and widespread applications, the presence of BPA is ubiquitous in the environment. BPA can enter the body via different ways such as digestive tract, respiratory tract and dermal tract. As an endocrine disruptor, BPA has estrogen-like and anti-androgen effects causing damages to different tissues and organs, including reproductive system, immune system and neuroendocrine system, etc. Recently, it has been shown that BPA could induce carcinogenesis and mutagenesis in animal models. Here, the underlying mechanisms of BPA-induced multi-organ toxicity were well summarized, involving the receptor pathways, disruption of neuroendocrine system, inhibition of enzymes, modulation of immune and inflammatory responses, as well as genotoxic and epigenetic mechanisms. The aim of this review is to compile the available current research data regarding BPA and provide an overview of the current status of BPA exposure and relevant health effects covering reproductive, developmental, metabolic, immuno, respiratory, hepatic and renal toxicity and carcinogenesis of BPA. This review provides comprehensive data of BPA toxicity on human health and related mechanisms. We also identify any missing data which should be addressed by further studies.

Effects of Bisphenol A on endogenous retroviral envelopes expression and trophoblast fusion in BeWo cells

Placenta is a target organ of Bisphenol A (BPA). To investigate possible effects on syncytiotrophoblast, the exchanging surface between mother and fetus, we exposed a trophoblast model (BeWo) to BPA concentrations occurring in humans (1 and 50 nM). We assessed the gene and protein expression of three human endogenous retroviral envelopes, specifically expressed in placenta (ERVW-1, ERVFRD-1 and ERV3-1), the secretion of β-hCG, the extent of trophoblast fusion and the activity of apoptosis markers (caspases 8, 3, 9 and PARP); additionally, the gene expression of transcription factors regulating HERV expression (i.e. GCM1, PPARγ, ERα and ERβ) was evaluated. At 50 nM, BPA induced ERVW-1, ERVFRD-1 and the corresponding syncytin proteins, ERV3-1, PPARγ, ERα and ERβ expression, increased β-hCG secretion and BeWo cells fusion, thus promoting the syncytiotrophoblast phenotype. The results support placenta as a target organ of BPA. Possible implications on fetal and pregnancy health should be carefully considered.

Exposure to phthalate metabolites, phenols and organophosphate pesticide metabolites and blood pressure during pregnancy

INTRODUCTION

Hypertensive disorders during pregnancy are one of the leading causes of maternal and offspring mortality and morbidity. Exposure to environmental chemicals is suspected to increase blood pressure (BP) but few studies have investigated the impact of non-persistent chemicals, in particular among pregnant women.

METHODS

Women included in the study were 152 volunteer participants in the Human Early-Life Exposome (HELIX) project. They provided 3 urine samples daily over one week in two pregnancy trimesters (at around 18 and 32 weeks of gestation) to assess their exposure to phthalates (10 metabolites), phenols (7 compounds) and organophosphate pesticides (4 metabolites). BP was measured at the end of the two collection weeks. Associations between biomarkers of exposure and BP were investigated using generalized estimating equations (GEE) and linear regression, and adjusted for potential confounders.

RESULTS

A significant decrease in systolic and/or diastolic BP was observed with exposure to some phthalate metabolites, BPA, and parabens (e.g. β GEE models for systolic BP = -0.91 mmHg (95%CI: -1.65; -0.17) per doubling of BPA concentrations). These associations were more frequently observed in the second trimester of pregnancy and remained statistically significant after correction for multiple testing for BPA only. No associations were observed with organophosphate pesticides.

CONCLUSION

This study investigates the effect of exposure to non-persistent chemicals assessed using multiple biospecimens per subject on BP during pregnancy and suggests that higher exposure to some phthalates and phenols but not pesticides is associated with lower BP during pregnancy.

Genetic Variants in Preeclampsia: Lessons From Studies in Latin-American Populations

Placental vascularization is a tightly regulated physiological process in which the maternal immune system plays a fundamental role. Vascularization of the maternal-placental interface involves a wide range of mechanisms primarily orchestrated by the fetal extravillous trophoblast and maternal immune cells. In a healthy pregnancy, an immune cross-talk between the mother and fetal cells results in the secretion of immunomodulatory mediators, apoptosis of specific cells, cellular differentiation/proliferation, angiogenesis, and vasculogenesis, altogether favoring a suitable microenvironment for the developing embryo. In the context of vasculopathy underlying common pregnancy disorders, it is believed that inefficient invasion of extravillous trophoblast cells in the endometrium leads to a poor placental blood supply, which, in turn, leads to decreased secretion of angiogenic factors, hypoxia, and inflammation commonly associated with preterm delivery, intrauterine growth restriction, and preeclampsia. In this review, we will focus on studies published by Latin American research groups, providing an extensive review of the role of genetic variants from candidate genes involved in a broad spectrum of biological processes underlying the pathophysiology of preeclampsia. In addition, we will discuss how these studies contribute to fill gaps in the current understanding of preeclampsia. Finally, we discuss some trending topics from important fields associated with pregnancy vascular disorders (e.g., epigenetics, transplantation biology, and non-coding RNAs) and underscore their possible implications in the pathophysiology of preeclampsia. As a result, these efforts are expected to give an overview of the extent of scientific research produced in Latin America and encourage multicentric collaborations by highlighted regional research groups involved in preeclampsia investigation.

Bisphenol A exposure alters placentation and causes preeclampsia-like features in pregnant mice involved in reprogramming of DNA methylation of WNT2

Preeclampsia leads to adverse outcomes for pregnant women. Bisphenol A (BPA) is an environmental endocrine disruptor and has been shown to be positively associated with increased risk of preeclampsia in human studies. We investigated whether BPA exposure causes preeclampsia-like features in pregnant mice and the associated underlying mechanisms. Experiments were performed in animal models and cell cultures. In pregnant mice, BPA-exposed mice exhibited preeclampsia-like features including hypertension, disruption of the circulation, and the placental angiogenesis biomarkers fms-related tyrosine kinase 1 and placenta growth factor, and glomerular atrophy; urinary protein was not affected. These preeclampsia-like features correlated with increased retention of smooth muscle cells and reduced vessel areas at the junctional zone of the placenta. In addition, there were disrupted expression of invasion-related genes including increased tissue inhibitors of metalloproteinases, decreased metalloproteinases, and Wnt family member WNT2/β-catenin, which correlated with increased DNA methylation in its promoter region and upregulation of DNA methyltransferase (Dnmt)1. BPA exposure impeded the interaction between the human cytotrophoblast cell line, HTR-8/SVneo, and endothelium cells. BPA exposure down-regulated WNT2 expression, and elevated the DNA methylation of WNT2; these results were consistent with in vivo observations. Inhibition of DNMT in HTR-8/SVneo cells resulted in reduced DNA methylation and increased expression of WNT2. Taken together, these data demonstrate that BPA exposure alters trophoblast cell invasion and causes abnormal placental vessel remodeling, both of which lead to the development of preeclampsia-like features in pregnant mice. Our results suggest that this phenomenon involves the epigenetic reprogramming and down-regulation of WNT2 mediated by DNMT1.-Ye, Y., Tang, Y., Xiong, Y., Feng, L., Li, X. Bisphenol A exposure alters placentation and causes preeclampsia-like features in pregnant mice involved in reprogramming of DNA methylation of WNT2.

Environmental Toxicant Exposure and Hypertensive Disorders of Pregnancy: Recent Findings

PURPOSE OF REVIEW

To assess the strength of evidence for associations between environmental toxicants and hypertensive disorders of pregnancy, suggest potential biological mechanisms based on animal and in vitro studies, and highlight avenues for future research.

RECENT FINDINGS

Evidence is strongest for links between persistent chemicals, including lead, cadmium, organochlorine pesticides, and polycyclic biphenyls, and preeclampsia, although associations are sometimes not detectable at low-exposure levels. Results have been inconclusive for bisphenols, phthalates, and organophosphates. Biological pathways may include oxidative stress, epigenetic changes, endocrine disruption, and abnormal placental vascularization. Additional prospective epidemiologic studies beginning in the preconception period and extending postpartum are needed to assess the life course trajectory of environmental exposures and women's reproductive and cardiovascular health. Future studies should also consider interactions between chemicals and consider nonlinear associations. These results confirm recommendations by the International Federation of Gynecology and Obstetrics, the American Society for Reproductive Medicine, the American Academy of Pediatrics, and the Endocrine Society that providers counsel their pregnant patients to limit exposure to environmental toxicants.

hCG and Its Disruption by Environmental Contaminants during Human Pregnancy

Human chorionic gonadotropin (hCG) is a hormone of considerable importance in the establishment, promotion and maintenance of human pregnancy. It has been clearly demonstrated that hCG exerts multiple endocrine, paracrine and autocrine actions on a variety of gestational and non-gestational cells and tissues. These actions are directed to promote trophoblast invasiveness and differentiation, placental growth, angiogenesis in uterine vasculature, hormone production, modulation of the immune system at the maternal-fetal interface, inhibition of myometrial contractility as well as fetal growth and differentiation. In recent years, considerable interest has been raised towards the biological effects of environmental contaminants, particularly endocrine disrupting chemicals (EDCs). Emerging evidence suggests that prenatal exposure to selected EDCs can have a deleterious impact on the fetus and long-lasting consequences also in adult life. The results of the in vitro effects of commonly found EDCs, particularly Bisphenol A (BPA) and para-Nonylphenol (p-NP), indicate that these substances can alter hCG production and through this action could exert their fetal damage, suggesting that hCG could represent and become a potentially useful clinical biomarker of an inappropriate prenatal exposure to these substances.

Environmental contaminants and preeclampsia: a systematic literature review

Preeclampsia is a medical condition specific to pregnancy characterized by high blood pressure and protein in the woman's urine, indicating kidney damage. It is one of the most serious reproductive conditions, posing substantial risks to the baby and potentially fatal for the mother. The causes of preeclampsia are largely unknown and environmental contaminants merit further investigation. The aim of this review was to determine the association between environmental chemical exposures and preeclampsia. PubMed was searched for articles examining a priori chemical exposures and preeclampsia through April 2018. Studies were included in our review if they included at least 10 cases, evaluated preeclampsia independent of gestational hypertension, and used either measured or modeled exposure assessments. Our review contained 28 investigations examining persistent organic pollutants (POP) (6 studies), drinking water contaminants (1 study), atmospheric pollutants (11 studies), metals and metalloids (6 studies), and other environmental contaminants (4 studies). There were an insufficient number of investigations on most chemicals to draw definitive conclusions, but strong evidence existed for an association between preeclampsia and cadmium (Cd). There is suggestive evidence for associations between nitrogen dioxide (NO₂), particulate matter (PM)_2.5, and traffic exposure with preeclampsia. There is evidence for an association between preeclampsia and Cd but insufficient literature to evaluate many other environmental chemicals. Additional studies using repeated measures, appropriate biological matrices, and mixtures methods are needed to expand this area of research and address the limitations of previous studies.