Fetal exposure of rhesus macaques to bisphenol a alters cellular development of the conducting airway by changing epithelial secretory product expression

Initiation of Cancer: The Journey From Mutations in Somatic Cells to Epigenetic Changes in Tissue-resident VSELs

Multiple theories exist to explain cancer initiation, although a consensus on this is crucial for developing effective therapies. 'Somatic mutation theory' suggests that mutations in somatic cells during DNA repair initiates cancer but this concept has several attached paradoxes. Research efforts to identify quiescent cancer stem cells (CSCs) that survive therapy and result in metastasis and recurrence have remained futile. In solid cancers, CSCs are suggested to appear during epithelial-mesenchymal transition by the dedifferentiation and reprogramming of epithelial cells. Pluripotent and quiescent very small embryonic-like stem cells (VSELs) exist in multiple tissues but remain elusive owing to their small size and scarce nature. VSELs are developmentally connected to primordial germ cells, undergo rare, asymmetrical cell divisions and are responsible for the regular turnover of cells to maintain tissue homeostasis throughout life. VSELs are directly vulnerable to extrinsic endocrine insults because they express gonadal and gonadotropin hormone receptors. VSELs undergo epigenetic changes due to endocrine insults and transform into CSCs. CSCs exhibit genomic instability and develop mutations due to errors during DNA replication while undergoing excessive proliferation and clonal expansion to form spheroids. Thus tissue-resident VSELs offer a connection between extrinsic insults and variations in cancer incidence reported in various body tissues. To conclude, cancer is indeed a stem cell disease with mutations occurring as a consequence. In addition to immunotherapy, targeting mutations, and Lgr5 + organoids for developing new therapeutics, targeting CSCs (epigenetically altered VSELs) by improving their niche and epigenetic status could serve as a promising strategy to treat cancer.

Bisphenol A exposure exacerbates tracheal inflammatory injury in selenium-deficient chickens by regulating the miR-155/TRAF3/ROS pathway

Bisphenol A (BPA) is an endocrine disruptor. Excessive BPA intake can damage the structure and function of the respiratory tract. Dietary selenium (Se) deficiency may also cause immune tissue damage. To investigate the potential mechanism of BPA on tracheal damage in selenium-deficient chickens and the role of microRNAs (miRNAs) in this process, we established in vitro and in vivo Se deficiency and BPA exposure models and screened out miR-155 for follow-up experiments. We further predicted and confirmed the targeting relationship between miR-155 and TRAF3 using TargetScan and dual luciferase assays and found that miR-155 was highly expressed and caused inflammatory damage. Further studies showed that BPA exposure increased airway oxidative stress, activated the NF-κB pathway, and caused inflammation and immune damage in selenium-deficient chickens, but down-regulating miR-155 and NAC treatment could reverse this phenomenon. This suggested that these pathways are regulated by the miR-155/TRAF3/ROS axis. In conclusion, BPA exposure aggravates airway inflammation in selenium-deficient chickens by regulating miR-155/TRAF3/ROS. This study revealed the mechanism of BPA exposure combined with Se deficiency in tracheal inflammatory injury in chickens and enriched the theoretical basis of BPA injury in poultry.

The role of neutrophil extracellular traps in sepsis and sepsis-related acute lung injury

Neutrophils release neutrophil extracellular traps (NETs) to trap pathogenic microorganisms. NETs are involved in the inflammatory response and bacterial killing and clearance. However, their excessive activation can lead to an inflammatory storm in the body, which may damage tissues and cause organ dysfunction. Organ dysfunction is the main pathophysiological cause of sepsis and also a cause of the high mortality rate in sepsis. Acute lung injury caused by sepsis accounts for the highest proportion of organ damage in sepsis. NET formation can lead to the development of sepsis because by promoting the release of interleukin-1 beta, interleukin-8, and tumor necrosis factor-alpha, thereby accelerating acute lung injury. In this review, we describe the critical role of NETs in sepsis-associated acute lung injury and review the current knowledge and novel therapeutic approaches.

Bisphenol and phthalate exposure during pregnancy and the development of childhood lung function and asthma. The generation R study

BACKGROUND

Fetal exposure to bisphenols and phthalates may lead to alterations in the respiratory and immune system development in children, and to adverse respiratory health. AIMTO STUDY: the associations of fetal bisphenols and phthalates exposure with lung function and asthma at age 13 years.

STUDY DESIGN

and Methods This study among 1020 children was embedded in a population-based prospective cohort study. We measured maternal urine bisphenol and phthalate concentrations in first, second and third trimester of pregnancy, and lung function by spirometry and asthma by questionnaires at age 13 years. Multivariable linear and logistic regression models were applied.

RESULTS

Maternal urine bisphenol and phthalate concentrations averaged during pregnancy were not associated with childhood lung function or asthma. Associations of maternal urine bisphenol and phthalate concentrations in specific trimesters with respiratory outcomes showed that one interquartile range increase in the natural log transformed maternal urine mono-isobutyl phthalate concentration in second trimester was associated with a higher FEV₁/FVC, but not with asthma, accounting for confounders and multiple-testing correction. Although there were associations of higher second trimester bisphenol S with a lower FVC and FEV₁ in boys and girls, and of higher first trimester bisphenol S with a decreased risk of asthma in boys and an increased risk of asthma in girls, these results did not remain significant after correction for multiple testing. Results were not modified by maternal history of asthma or atopy.

CONCLUSIONS

Maternal urine bisphenol and phthalate concentrations averaged or in specific trimesters during pregnancy were not strongly associated with childhood lung function and asthma at age 13 years. BPS, as a BPA substitute, tended to be associated with impaired lung function and altered risk of asthma, partly sex-dependent, but its strength was limited by a relatively low detection rate and should be queried in contemporary cohorts.

In utero exposure to bisphenols and asthma, wheeze, and lung function in school-age children: a prospective meta-analysis of 8 European birth cohorts

BACKGROUND

In utero exposure to bisphenols, widely used in consumer products, may alter lung development and increase the risk of respiratory morbidity in the offspring. However, evidence is scarce and mostly focused on bisphenol A (BPA) only.

OBJECTIVE

To examine the associations of in utero exposure to BPA, bisphenol F (BPF), and bisphenol S (BPS) with asthma, wheeze, and lung function in school-age children, and whether these associations differ by sex.

METHODS

We included 3,007 mother-child pairs from eight European birth cohorts. Bisphenol concentrations were determined in maternal urine samples collected during pregnancy (1999-2010). Between 7 and 11 years of age, current asthma and wheeze were assessed from questionnaires and lung function by spirometry. Wheezing patterns were constructed from questionnaires from early to mid-childhood. We performed adjusted random-effects meta-analysis on individual participant data.

RESULTS

Exposure to BPA was prevalent with 90% of maternal samples containing concentrations above detection limits. BPF and BPS were found in 27% and 49% of samples. In utero exposure to BPA was associated with higher odds of current asthma (OR = 1.13, 95% CI = 1.01, 1.27) and wheeze (OR = 1.14, 95% CI = 1.01, 1.30) (p-interaction sex = 0.01) among girls, but not with wheezing patterns nor lung function neither in overall nor among boys. We observed inconsistent associations of BPF and BPS with the respiratory outcomes assessed in overall and sex-stratified analyses.

CONCLUSION

This study suggests that in utero BPA exposure may be associated with higher odds of asthma and wheeze among school-age girls.

Endocrine-Disrupting Chemicals and Their Adverse Effects on the Endoplasmic Reticulum

There is growing concern regarding the health and safety issues of endocrine-disrupting chemicals (EDCs). Long-term exposure to EDCs has serious adverse health effects through both hormone-direct and hormone-indirect ways. Accordingly, some EDCs can be a pathogen and an inducer to the susceptibility of disease, even if they have a very low affinity on the estrogen receptor, or no estrogenic effect. Endoplasmic reticulum (ER) stress recently attracted attention in this research area. Because ER and ER stress could be key regulators of the EDC’s adverse effects, such as the malfunction of the organ, as well as the death, apoptosis, and proliferation of a cell. In this review, we focused on finding evidence which shows that EDCs could be a trigger for ER stress and provide specific examples of EDCs, which are known to cause ER stress currently.

Update on the Health Effects of Bisphenol A: Overwhelming Evidence of Harm

In 1997, the first in vivo bisphenol A (BPA) study by endocrinologists reported that feeding BPA to pregnant mice induced adverse reproductive effects in male offspring at the low dose of 2 µg/kg/day. Since then, thousands of studies have reported adverse effects in animals administered low doses of BPA. Despite more than 100 epidemiological studies suggesting associations between BPA and disease/dysfunction also reported in animal studies, regulatory agencies continue to assert that BPA exposures are safe. To address this disagreement, the CLARITY-BPA study was designed to evaluate traditional endpoints of toxicity and modern hypothesis-driven, disease-relevant outcomes in the same set of animals. A wide range of adverse effects was reported in both the toxicity and the mechanistic endpoints at the lowest dose tested (2.5 µg/kg/day), leading independent experts to call for the lowest observed adverse effect level (LOAEL) to be dropped 20 000-fold from the current outdated LOAEL of 50 000 µg/kg/day. Despite criticism by members of the Endocrine Society that the Food and Drug Administration (FDA)'s assumptions violate basic principles of endocrinology, the FDA rejected all low-dose data as not biologically plausible. Their decisions rely on 4 incorrect assumptions: dose responses must be monotonic, there exists a threshold below which there are no effects, both sexes must respond similarly, and only toxicological guideline studies are valid. This review details more than 20 years of BPA studies and addresses the divide that exists between regulatory approaches and endocrine science. Ultimately, CLARITY-BPA has shed light on why traditional methods of evaluating toxicity are insufficient to evaluate endocrine disrupting chemicals.

Prenatal Bisphenol A Exposure Alters Epithelial Cell Composition in the Rhesus Macaque Fetal Oviduct

Bisphenol A (BPA) is an endocrine disrupting compound that is a pervasive environmental contaminant. Although it has been reported to affect the development of a variety of fetal reproductive tissues, data on the effect of fetal BPA exposure on oviducts were extremely limited and were only available in mice. To determine if there are adverse effects of gestational BPA exposure on fetal oviduct, we exposed pregnant rhesus macaques with female fetuses to oral or nonoral BPA during the last trimester of gestation (day 100 to term). After the treatment, fetal oviducts were collected for morphology evaluation. BPA exposure altered the percentages of different cell types (ciliated, nonciliated, and secretory) in the fetal oviduct and resulted in a significant high ciliated cell population in the BPA-exposed fetal oviduct. The distribution of ciliated cells on the epithelium in the BPA-exposed fetal oviduct was also altered. Gestational BPA exposure reduced the expression of mucosubstance and uteroglobin in secretory cells in the fetal oviduct. A comparison of the outcome of the fetal oviduct studies with similar outcomes previously reported in the lung from the same fetuses demonstrates that BPA exhibits opposite effects in these two organs. In conclusion, the BPA-associated alterations in the fetal oviduct could potentially affect the oviduct morphology and function later in life with a negative impact on fertility. The mechanisms of action of the differential response in the oviduct and the lung to BPA exposure require further investigation.

Changes in gene expression following long-term in vitro exposure of Macaca mulatta trophoblast stem cells to biologically relevant levels of endocrine disruptors

Trophoblast stem cells (TSCs) are crucial for embryo implantation and placentation. Environmental toxicants that compromise TSC function could impact fetal viability, pregnancy, and progeny health. Understanding the effects of low, chronic EDC exposures on TSCs and pregnancy is a priority in developmental toxicology. Differences in early implantation between primates and other mammals make a nonhuman primate model ideal. We examined effects of chronic low-level exposure to atrazine, tributyltin, bisphenol A, bis(2-ethylhexyl) phthalate, and perfluorooctanoic acid on rhesus monkey TSCs in vitro by RNA sequencing. Pathway analysis of affected genes revealed negative effects on cytokine signaling related to anti-viral response, most strongly for atrazine and tributyltin, but shared with the other three EDCs. Other affected processes included metabolism, DNA repair, and cell migration. Low-level chronic exposure of primate TSCs to EDCs may thus compromise trophoblast development in vivo, inhibit responses to infection, and negatively affect embryo implantation and pregnancy.

A systematic review of metabolomics biomarkers for Bisphenol A exposure

INTRODUCTION

Bisphenol A (BPA), 2,2-bis(4-hydroxyphenyl) propane, a common industrial chemical which has extremely huge production worldwide, is ubiquitous in the environment. Human have high risk of exposing to BPA and the health problems caused by BPA exposure have aroused public concern. However, the biomarkers for BPA exposure are lacking. As a rapidly developing subject, metabolomics has accumulated a large amount of valuable data in various fields. The secondary application of published metabolomics data could be a very promising field for generating novel biomarkers whilst further understanding of toxicity mechanisms.

OBJECTIVES

To summarize the published literature on the use of metabolomics as a tool to study BPA exposure and provide a systematic perspectives of current research on biomarkers screening of BPA exposure.

METHODS

We conducted a systematic search of MEDLINE (PubMed) up to the end of June 25, 2017 with the key term combinations of 'metabolomics', 'metabonomics', 'mass spectrometry', 'nuclear magnetic spectroscopy', 'metabolic profiling' and 'amino acid profile' combined with 'BPA exposure'. Additional articles were identified through searching the reference lists from included studies.

RESULTS

This systematic review included 15 articles. Intermediates of glycolysis, Krebs cycle, β oxidation of long chain fatty acids, pentose phosphate pathway, nucleoside metabolism, branched chain amino acid metabolism, aromatic amino acids metabolism, sulfur-containing amino acids metabolism were significantly changed after BPA exposure, suggesting BPA had a highly complex toxic effects on organism which was consistent with existing studies. The biomarkers most consistently associated with BPA exposure were lactate and choline.

CONCLUSION

Existing metabolomics studies of BPA exposure present heterogeneous findings regarding metabolite profile characteristics. We need more evidence from target metabolomics and epidemiological studies to further examine the reliability of these biomarkers which link to low, environmentally relevant, exposure of BPA in human body.

Urinary bisphenol A concentrations in relation to asthma in a sample of Egyptian children

BACKGROUND

Bronchial asthma is one of the top disabling diseases in pediatrics. Limited research has been studied the association of the widely used plastic monomer bisphenol A (BPA) with childhood asthma.

OBJECTIVE

To compare the levels of urinary BPA in asthmatic and control children and to investigate the implication of BPA among other risk factors for the development of asthma.

SUBJECTS AND METHODS

This case-control study included 97 children (45 asthmatic and 52 healthy controls) aged 3-8 years. Asthmatic children were diagnosed according to Global initiative for asthma (GINA) guidelines. Sociodemographic factors were assessed and urinary levels of BPA were determined in spot urine samples using high-performance liquid chromatography. The contribution of BPA among predictors for developing asthma was studied in asthmatic children.

RESULTS

Median total urinary BPA levels were significantly higher in asthmatic children than in control group (1.56 ng/mL in asthmatic children compared to 0.790 ng/mL in control group, p = 0.001). Children who had total urinary BPA levels >1.3 ng/mL were more likely to be asthmatic (odds ratio: 2.84, 95% confidence interval 1.22-6.59, p = 0.015). Multiple logistic regression analysis for predictors of asthma showed the importance of higher levels of BPA (>1.3 ng/mL) as a more significant predictor than passive smoking ( p = 0.006 for BPA categories vs. p = 0.049 for passive smoking).

CONCLUSION

Association of higher levels of urinary BPA with the diagnosis of asthma in children may indicate the potential risk of BPA exposure in the precipitation of bronchial asthma. Further clinical and biochemical research are needed to clarify the proper mechanism explaining this association.

Preparation of Specific Compartments of the Lungs for Pathologic and Biochemical Analysis of Toxicologic Responses

This unit focuses on protocols for assessing microenvironment-specific responses in the thoracic lung tissues. Aspects of the entire respiratory system serve as potential targets for candidate toxicants, but each candidate toxicant may impact distinct sites due to differential distribution of either the toxicant or the target cells. Within the conducting airways, the composition of resident cell populations and the metabolic capabilities of the cell populations vary greatly. Thus, studies of this region of the lung require unique, site-selective methods to clearly define the toxic response. Without site-specific sampling, as described in this chapter, the experimental limit of detection for toxicant effects in conducting airways is weakened because differences unrelated to treatment, but related to location, may dominate the response. The protocols included here allow assessment of toxicological responses in the tracheobronchial airways and the gas exchange area of the lung, with specific application to laboratory mammals. © 2017 by John Wiley & Sons, Inc.

Molecular targets of developmental exposure to bisphenol A in diabesity: a focus on endoderm-derived organs

Several studies associate foetal human exposure to bisphenol A (BPA) to metabolic/endocrine diseases, mainly diabesity. They describe the role of BPA in the disruption of pancreatic beta cell, adipocyte and hepatocyte functions. Indeed, the complexity of the diabesity phenotype is due to the involvement of different endoderm-derived organs, all targets of BPA. Here, we analyse this point delineating a picture of different mechanisms of BPA toxicity in endoderm-derived organs leading to diabesity. Moving from epidemiological data, we summarize the in vivo experimental data of the BPA effects on endoderm-derived organs (thyroid, pancreas, liver, gut, prostate and lung) after prenatal exposure. Mainly, we gather molecular data evidencing harmful effects at low-dose exposure, pointing to the risk to human health. Although the fragmentation of molecular data does not allow a clear conclusion to be drawn, the present work indicates that the developmental exposure to BPA represents a risk for endoderm-derived organs development as it deregulates the gene expression from the earliest developmental stages. A more systematic analysis of BPA impact on the transcriptomes of endoderm-derived organs is still missing. Here, we suggest in vitro toxicogenomics approaches as a tool for the identification of common mechanisms of BPA toxicity leading to the diabesity in organs having the same developmental origin.

Effects of Bisphenol A Metabolite 4-Methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene on Lung Function and Type 2 Pulmonary Alveolar Epithelial Cell Growth

Bisphenol A (BPA) is recognized as a major pollutant worldwide. 4-Methyl-2,4-bis(4-hydroxyphenyl)pent-1-ene (MBP) is a major active metabolite of BPA. The epidemiological and animal studies have reported that BPA is harmful to lung function. The role of MBP in lung dysfunction after BPA exposure still remains unclear. This study investigated whether MBP would induce lung alveolar cell damage and evaluated the role of MBP in the BPA exposure-induced lung dysfunction. An in vitro type 2 alveolar epithelial cell (L2) model and an ex vivo isolated reperfused rat lung model were used to determine the effects of BPA or MBP on cell growth and lung function. MBP, but not BPA, dose-dependently increased the mean artery pressure (Pa), pulmonary capillary pressure (Pc), pulmonary capillary filtration coefficient (K_fc), and wet/dry weight ratio in isolated reperfused rat lungs. MBP significantly reduced cell viability and induced caspases-3/7 cleavage and apoptosis and increased AMP-activated protein kinas (AMPK) phosphorylation and endoplasmic reticulum (ER) stress-related molecules expression in L2 cells, which could be reversed by AMPK-siRNA transfection. These findings demonstrated for the first time that MBP exposure induced type 2 alveolar cell apoptosis and lung dysfunction through an AMPK-regulated ER stress signaling pathway.

Maternal and Fetal Pharmacokinetics of Oral Radiolabeled and Authentic Bisphenol A in the Rhesus Monkey

The present study was conducted in pregnant rhesus monkeys to determine the rapidity and extent to which BPA reaches the fetal compartment following oral ingestion, and the 24-hr fate of BPA. To assess metabolism changes during the course of pregnancy, we compared BPA biotransformation during the second and third trimesters in the same animals, measuring the levels of sulfated, gluronidated, and free BPA in maternal serum, amniotic fluid, and fetal serum. All animals showed measurable unconjugated and conjugated BPA in the fetal compartment and slow clearance compared to maternal serum. There were higher levels of BPA-G in amniotic fluid at 150 days gestation compared to 100 days gestation, as well as higher levels of BPA-G than BPA-S. We also monitored ³H-BPA (and metabolites) in key tissues and excreta from a mother and fetus and from a non-pregnant female. The elimination of radioactivity was rapid, but residues were still detectable 24 hr after dosing in all tissues analyzed. These data suggest that, in primates, rapid maternal processing of BPA does not alleviate the risk of exposure to the developing fetus. This study elevates concerns about levels of current BPA human exposure from potentially a large number of unknown sources and the risks posed to developing fetuses.

Bisphenol A exposure alters release of immune and developmental modulators and expression of estrogen receptors in human fetal lung fibroblasts

Bisphenol A (BPA) has been shown to exert biological effects through estrogen receptor (ER)-dependent and ER-independent mechanisms. Recent studies suggest that prenatal exposure to BPA may increase the risk of childhood asthma. To investigate the underlying mechanisms in the actions of BPA, human fetal lung fibroblasts (hFLFs) were exposed to varying doses of BPA in culture for 24hr. Effects of BPA on localization and uptake of BPA, cell viability, release of immune and developmental modulators, cellular localization and expression of ERα, ERβ and G-protein coupled estrogen receptor 30 (GPR30), and effects of ERs antagonists on BPA-induced changes in endothelin-1 (ET-1) release were examined. BPA at 0.01-100μmol/L caused no changes in cell viability after 24hr of exposure. hFLFs expresses all three ERs. BPA had no effects on either cellular distribution or protein expression of ERα, however, at 100μmol/L (or 23μmol/L intracellular BPA) increased ERβ protein levels in the cytoplasmic fractions and GPR30 protein levels in the nuclear fractions. These paralleled with increased release of growth differentiation factor-15, decreased phosphorylation of nuclear factor kappa B p65 at serine 536, and decreased release of ET-1, interleukin-6, and interferon gamma-induced protein 10. ERs antagonists had no effects on BPA-induced decrease in ET-1 release. These data suggest that BPA at 100μmol/L altered the release of immune and developmental modulators in hFLFs, which may negatively influence fetal lung development, maturation, and susceptibility to environmental stressors, although the role of BPA in childhood asthma remains to be confirmed in in vivo studies.

An old culprit but a new story: bisphenol A and "NextGen" bisphenols

The concept that developmental events shape adult health and disease was sparked by the recognition of a link between maternal undernutrition and coronary disease in adults. From that beginning, a new field-the developmental origins of health and disease-emerged, and attention has focused on the effects of a wide array of developmental perturbations. Exposure to endocrine-disrupting chemicals has been of particular interest, and a ubiquitous environmental contaminant bisphenol A (BPA) has become the endocrine-disrupting chemical poster child. Bisphenol A has been the subject of intense investigation for nearly two decades, and exposure effects have been described in hundreds of experimental, epidemiological, and clinical studies. From the standpoint of reproductive health, the findings are particularly important, as they suggest that the ovary, testis, and reproductive tract in both sexes are targets of BPA action. The findings and the media and regulatory attention garnered by them have generated increasing public concern and resulted in legislative bans on BPA in some countries. The subsequent introduction of BPA-free products, although a masterful marketing strategy, is in reality only the beginning of a new and complex chapter of the BPA story. In this review we attempt to summarize what we have learned about the reproductive effects of BPA, present the reasons why studying the effects of this chemical in humans is no longer sufficient, and outline the challenges that the growing array of next generation bisphenols represents to clinicians, researchers, federal agencies, and the general public.

Effects of long-term endocrine disrupting compound exposure on Macaca mulatta embryonic stem cells

Endocrine disrupting chemicals (EDCs) exert significant effects on health and physiology, many traceable to effects on stem cell programming underlying development. Understanding risk of low-level, chronic EDC exposure will be enhanced by knowledge of effects on stem cells. We exposed rhesus monkey embryonic stem cells to low levels of five EDCs [bisphenol A (BPA), atrazine (ATR), tributyltin (TBT), perfluorooctanoic acid (PFOA), and di-(2-ethylhexyl) phthalate (DEHP)] for 28days, and evaluated effects on gene expression by RNAseq transcriptome profiling. We observed little effect of BPA, and small numbers of affected genes (≤119) with other EDCs. There was substantial overlap in effects across two, three, or four treatments. Ingenuity Pathway analysis indicated suppression of cell survival genes and genes downstream of several stress response mediators, activation of cell death genes, and modulations in several genes regulating pluripotency, differentiation, and germ layer development. Potential adverse effects of these changes on development are discussed.

Women and Lung Disease. Sex Differences and Global Health Disparities

There is growing evidence that a number of pulmonary diseases affect women differently and with a greater degree of severity than men. The causes for such sex disparity is the focus of this Blue Conference Perspective review, which explores basic cellular and molecular mechanisms, life stages, and clinical outcomes based on environmental, sociocultural, occupational, and infectious scenarios, as well as medical health beliefs. Owing to the breadth of issues related to women and lung disease, we present examples of both basic and clinical concepts that may be the cause for pulmonary disease disparity in women. These examples include those diseases that predominantly affect women, as well as the rising incidence among women for diseases traditionally occurring in men, such as chronic obstructive pulmonary disease. Sociocultural implications of pulmonary disease attributable to biomass burning and infectious diseases among women in low- to middle-income countries are reviewed, as are disparities in respiratory health among sexual minority women in high-income countries. The implications of the use of complementary and alternative medicine by women to influence respiratory disease are examined, and future directions for research on women and respiratory health are provided.

Evidence that bisphenol A (BPA) can be accurately measured without contamination in human serum and urine, and that BPA causes numerous hazards from multiple routes of exposure

There is extensive evidence that bisphenol A (BPA) is related to a wide range of adverse health effects based on both human and experimental animal studies. However, a number of regulatory agencies have ignored all hazard findings. Reports of high levels of unconjugated (bioactive) serum BPA in dozens of human biomonitoring studies have also been rejected based on the prediction that the findings are due to assay contamination and that virtually all ingested BPA is rapidly converted to inactive metabolites. NIH and industry-sponsored round robin studies have demonstrated that serum BPA can be accurately assayed without contamination, while the FDA lab has acknowledged uncontrolled assay contamination. In reviewing the published BPA biomonitoring data, we find that assay contamination is, in fact, well controlled in most labs, and cannot be used as the basis for discounting evidence that significant and virtually continuous exposure to BPA must be occurring from multiple sources.

Bisphenol a exposure and the development of wheeze and lung function in children through age 5 years

IMPORTANCE

Bisphenol A (BPA), a prevalent endocrine-disrupting chemical, has been associated with wheezing in children, but few studies have examined its effect on lung function or wheeze in older children.

OBJECTIVES

To test whether BPA exposure is associated with lung function, with wheeze, and with pattern of wheeze in children during their first 5 years.

DESIGN, SETTING, AND PARTICIPANTS

A birth cohort study, enrolled during early pregnancy in the greater Cincinnati, Ohio, area among 398 mother-infant dyads. We collected maternal urine samples during pregnancy (at 16 and 26 weeks) and child urine samples annually to assess gestational and child BPA exposure.

MAIN OUTCOMES AND MEASURES

We assessed parent-reported wheeze every 6 months for 5 years and measured child forced expiratory volume in the first second of expiration (FEV1) at age 4 and 5 years. We evaluated associations of BPA exposure with respiratory outcomes, including FEV1, child wheeze, and wheeze phenotype.

RESULTS

Urinary BPA concentrations and FEV1 data were available for 208 children and urinary BPA concentrations and parent-reported wheeze data were available for 360 children. The mean maternal urinary BPA concentration ranged from 0.53 to 293.55 µg/g of creatinine. In multivariable analysis, every 10-fold increase in the mean maternal urinary BPA concentration was associated with a 14.2% (95% CI, -24.5% to -3.9%) decrease in the percentage predicted FEV1 at 4 years, but no association was found at 5 years. In multivariable analysis, every 10-fold increase in the mean maternal urinary BPA concentration was marginally associated with a 54.8% increase in the odds of wheezing (adjusted odds ratio, 1.55; 95% CI, 0.91-2.63). While the mean maternal urinary BPA concentration was not associated with wheeze phenotype, a 10-fold increase in the 16-week maternal urinary BPA concentration was associated with a 4.27-fold increase in the odds of persistent wheeze (adjusted odds ratio, 4.27; 95% CI, 1.37-13.30). Child urinary BPA concentrations were not associated with FEV1 or wheeze.

CONCLUSIONS AND RELEVANCE

These results provide evidence suggesting that prenatal but not postnatal exposure to BPA is associated with diminished lung function and the development of persistent wheeze in children.

Prenatal exposure to bisphenol A and phthalates and childhood respiratory tract infections and allergy

BACKGROUND

There is growing concern that prenatal exposure to bisphenol A (BPA) and phthalates, which are widely used in consumer products, might affect susceptibility to infections and the development of allergy and asthma in children, but there are currently very few prospective studies.

OBJECTIVE

We sought to evaluate whether prenatal exposure to BPA and phthalates increases the risk of respiratory and allergic outcomes in children at various ages from birth to 7 years.

METHODS

We measured BPA and metabolites of high-molecular-weight phthalates, 4 di-(2-ethylhexyl) phthalate (DEHP) metabolites (Σ4DEHP) and mono-benzyl phthalate (MBzP), and 3 low-molecular-weight phthalate (LMWP) metabolites (Σ3LMWP) in urine samples collected during the first and third trimesters in pregnant women participating in the Infancia y Medio Ambiente-Sabadell birth cohort study. The occurrence of chest infections, bronchitis, wheeze, and eczema in children was assessed at ages 6 and 14 months and 4 and 7 years through questionnaires given to the mothers. Atopy (specific IgE measurement) and asthma (questionnaire) were assessed at ages 4 and 7 years, respectively.

RESULTS

The relative risks (RRs) of wheeze (RR, 1.20; 95% CI, 1.03-1.40; P = .02), chest infections (RR, 1.15; 95% CI, 1.00-1.32; P = .05), and bronchitis (RR, 1.18; 95% CI, 1.01-1.37; P = .04) at any age increased for each doubling in concentration of maternal urinary BPA. Σ4DEHP metabolites were associated with the same outcomes (wheeze: RR, 1.25; 95% CI, 1.04-1.50, P = .02; chest infections: RR, 1.15; 95% CI, 0.97-1.35; P = .11; bronchitis: RR, 1.20; 95% CI, 1.01-1.43; P = .04). MBzP was associated with higher risk of wheeze (RR, 1.15; 95% CI, 1.00-1.33; P = .05). The risk of asthma at age 7 years was also increased with increasing prenatal BPA, Σ4DEHP, and MBzP exposure. There were no other exposure-outcome associations.

CONCLUSIONS

Prenatal exposure to BPA and high-molecular-weight phthalates might increase the risk of asthma symptoms and respiratory tract infections throughout childhood.

Bisphenol A exposure and asthma development in school-age children: a longitudinal study

BACKGROUND

Although the effect of bisphenol A on various health outcomes has been extensively examined, few studies have investigated its effect on asthma.

OBJECTIVE

We hypothesized that exposure to bisphenol A in school-age children was associated with wheezing and asthma.

METHODS

Participants included 127 children aged 7-8 years without a previous asthma diagnosis in an elementary school in Seoul, Korea. Three surveys were conducted, each 2 years apart. Bisphenol A concentration was measured at the baseline survey, and PC20, which is defined as the methacholine concentration that induces a decrease in FEV1 of 20% from baseline, was measured at every survey. Associations between bisphenol A concentration at 7-8 years of age and wheezing, asthma, and PC20 at ages up to 11-12 years were examined using generalized estimating equations, a marginal Cox regression model, and a linear mixed model.

RESULTS

The log-transformed creatinine-adjusted urinary bisphenol A concentration at 7-8 years was positively associated with wheezing (odds ratio, 2.48; 95% confidence interval, 1.15-5.31; P = .02) and asthma (hazard ratio, 2.13; 95% confidence interval, 1.51-3.00; P<.001) at ages up to 11-12 years. Bisphenol A was also negatively associated with PC20 (ß = -2.33; P = .02). When stratified by sex, the association between bisphenol A and asthma remained significant only in girls (hazard ratio, 2.45; 95% confidence interval, 2.18-2.76; P<.001).

CONCLUSION

Increased urinary bisphenol A concentrations at 7-8 years old were positively associated with wheezing and asthma and negatively associated with PC20 at ages up to 11-12 years.

Lifetime-dependent effects of bisphenol A on asthma development in an experimental mouse model

BACKGROUND

Environmental factors are thought to contribute significantly to the increase of asthma prevalence in the last two decades. Bisphenol A (BPA) is a xenoestrogen commonly used in consumer products and the plastic industry. There is evidence and an ongoing discussion that endocrine disruptors like BPA may affect human health and also exert alterations on in the immune system. The aim of this study was to investigate age-dependent effects of BPA on the asthma risk using a murine model to explain the controversial results reported till date.

METHODS

BALB/c mice were exposed to BPA via the drinking water for different time periods including pregnancy and breastfeeding. To induce an asthma phenotype, mice were sensitized to ovalbumin (OVA), followed by an intrapulmonary allergen challenge.

RESULTS

BPA exposure during pregnancy and breastfeeding had no significant effect on asthma development in the offspring. In contrast, lifelong exposure from birth until the last antigen challenge clearly increased eosinophilic inflammation in the lung, airway hyperreactivity and antigen-specific serum IgE levels in OVA-sensitized adult mice compared to mice without BPA exposure. Surprisingly, BPA intake during the sensitization period significantly reduced the development of allergic asthma. This effect was reversed in the presence of a glucocorticoid receptor antagonist.

CONCLUSIONS

Our results demonstrate that the impact of BPA on asthma risk is strongly age-dependent and ranges from asthma-promoting to asthma-reducing effects. This could explain the diversity of results from previous studies regarding the observed health impact of BPA.

Bisphenol A exposure is associated with decreased lung function

OBJECTIVE

To examine the associations of bisphenol A (BPA) exposure with lung function measures and exhaled nitric oxide (FeNO) in children.

STUDY DESIGN

We performed a cross-sectional analysis of a subsample of US children age 6-19 years who participated in the 2007-2010 National Health and Nutrition Examination Survey. We assessed univariate and multivariable associations of urinary BPA concentration with the predicted pulmonary function measures for age, sex, race/ethnicity and height (forced expiratory volume in 1 second [FEV1], forced vital capacity [FVC], forced expiratory flow 25%-75%, and FEV1 divided by FVC) and with FeNO.

RESULTS

Exposure and outcome data were available for 661 children. Median BPA was 2.4 ng/mL (IQR: 1.3, 4.1). In multivariable analysis, a larger urinary BPA concentration was associated with significantly decreased percent predicted forced expiratory flow 25%-75% (%FEF2575) (3.7%, 95% CI 1.0, 6.5) and percent predicted FEV1 divided by FVC (%FEV1/FVC) (0.8%, 95% CI 0.1, 1.7) but not percent predicted FEV1, percent predicted FVC, or FeNO. A child in the top quartile of BPA compared with the bottom quartile had a 10% decrease in %FEF2575 (95% CI -1, -19) and 3% decrease in %FEV1/FVC (95% CI -1, -5).

CONCLUSIONS

BPA exposure was associated with a modest decrease in %FEF2575 (small airway function) and %FEV1/FVC (pulmonary obstruction) but not FEV1, FVC, or FeNO. Explanations of the association cannot rule out the possibility of reverse causality.

Bisphenol A (BPA) pharmacokinetics with daily oral bolus or continuous exposure via silastic capsules in pregnant rhesus monkeys: Relevance for human exposures

We measured serum dBPA in non-pregnant and pregnant female rhesus monkeys, fetuses and amniotic fluid. dBPA was administered by a daily oral bolus or sc implantation of Silastic capsules; both resulted in daily average serum unconjugated dBPA concentrations of <1ng/ml. We observed lower serum concentrations of unconjugated dBPA in pregnant females relative to pre-pregnancy values, and generally lower concentrations in fetal serum than in maternal serum. Differences in pharmacokinetics of dBPA were evident between pre-pregnancy, early and late pregnancy, likely reflecting changes in maternal, fetal and placental physiology. The serum ratio of conjugated to unconjugated dBPA after continuous sc release of dBPA was similar to values reported in human biomonitoring studies and markedly lower than with oral administration, suggesting oral bolus exposure is not an appropriate human exposure model. We report elsewhere that there were numerous adverse effects on fetuses exposed to very low serum dBPA in these studies.