The role of polycarbonate monomer bisphenol-A in insulin resistance

Bisphenol A induces non-alcoholic fatty liver disease by promoting the O-GlcNAcylation of NLRP3

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease. The mechanism by which bisphenol A (BPA) promots NAFLD remains unclear. Palmitic acid (PA) and lipopolysaccharide (LPS) were used to simulate NAFLD in HepG2 cells in vitro. Total cholesterol (TC), triglyceride (TG) content, and lipid accumulation were measured to evaluate lipid metabolism. The caspase-1-stained cells and NLRP3 inflammasome-associated proteins were evaluated for pyroptosis. Western blot analysis was used to detect protein levels and co-immunoprecipitation (Co-IP) was used to detect the association between the proteins. Cycloheximide (CHX) treatment combined with western blot was performed to access protein stability. This data have shown that BPA induces lipid metabolism dysfunction and pyroptosis by upregulating O-GlcNAc transferase (OGT) level. NLRP3 directly interacts with OGT, and elevated OGT enhanced the stability of NLRP3 protein. BPA promoted OGT-mediated O-GlcNAcylation to stabilised NLRP3, thus accelerating NAFLD progress in vitro. Our study reveals that BPA, as an environmental factor, may be involved in the promotion of NAFLD, and that targeting NLRP3 and OGT may inhibit BPA's induction of NAFLD.

Comparative G-Protein-Coupled Estrogen Receptor (GPER) Systems in Diabetic and Cancer Conditions: A Review

For many patients, diabetes Mellitus and Malignancy are frequently encountered comorbidities. Diabetes affects approximately 10.5% of the global population, while malignancy accounts for 29.4 million cases each year. These troubling statistics indicate that current treatment approaches for these diseases are insufficient. Alternative therapeutic strategies that consider unique signaling pathways in diabetic and malignancy patients could provide improved therapeutic outcomes. The G-protein-coupled estrogen receptor (GPER) is receiving attention for its role in disease pathogenesis and treatment outcomes. This review aims to critically examine GPER' s comparative role in diabetes mellitus and malignancy, identify research gaps that need to be filled, and highlight GPER's potential as a therapeutic target for diabetes and malignancy management. There is a scarcity of data on GPER expression patterns in diabetic models; however, for diabetes mellitus, altered expression of transport and signaling proteins has been linked to GPER signaling. In contrast, GPER expression in various malignancy types appears to be complex and debatable at the moment. Current data show inconclusive patterns of GPER expression in various malignancies, with some indicating upregulation and others demonstrating downregulation. Further research should be conducted to investigate GPER expression patterns and their relationship with signaling pathways in diabetes mellitus and various malignancies. We conclude that GPER has therapeutic potential for chronic diseases such as diabetes mellitus and malignancy.

Microplastics in food: scoping review on health effects, occurrence, and human exposure

With most of the plastics ever produced now being waste, slowly degrading and fragmenting in the environment, microplastics (MPs) have become an emerging concern regarding their presence in food and influence on human health. While many studies on marine ecotoxicology and the occurrence of MPs in fish and shellfish exist, research on the occurrence of MPs in other foods and their effect on human health is still in early-stage, but the attention is increasing. This review aimed to provide relevant information on the possible health effect of ingested MPs, the occurrence, and levels of MPs contamination in various foods and estimated exposure to MPs through food. Potential toxic consequences from exposure to MPs through food can arise from MPs themselves, diffused monomers and additives but also from sorbed contaminants or microorganisms that colonise MPs. Recent publications have confirmed widespread contamination of our food with MPs including basic and life-essential constituents such as water and salt providing the basis for chronic exposure. Available exposure assessments indicate that we ingest up to several hundred thousand MPs particles yearly.

Hydrothermal deconstruction of single-use personal protective equipment during the COVID-19 pandemic

To minimise the transmission of the SARS-CoV-2 virus, there has been a substantial increase in the production and usage of synthetic personal protective equipment (PPE) globally. Consequently, single-use PPE have been widely adopted without appropriate regulations for their disposal, leading to extensive environmental contamination worldwide. This study investigates the non-catalytic hydrothermal deconstruction of different PPE items, including isolation gowns, gloves, goggles, face shields, surgical masks, and filtering-facepiece respirators. The selected PPE items were subjected to hydrothermal deconstruction for 90 min in the presence of 30-bar initial oxygen pressure, at temperatures ranging between 250 °C and 350 °C. The solid content in form of total suspended solids (TSS) was reduced up to 97.6%. The total chemical oxygen demand (tCOD) and soluble chemical oxygen demand (sCOD) decreased with increasing deconstruction temperature, and at 350 °C the lowest tCOD and sCOD content of 546.6 mg/L and 470 mg/L, respectively, was achieved. Short-chained volatile fatty acids were produced after 90 min of deconstruction, predominantly acetic acid at concentrations up to 8974 mg/L. Ammonia nitrogen content (NH₃-N) of up to 542.6 mg/L was also detected. Carbon dioxide (CO₂) and unreacted oxygen (O₂) were the main gaseous by-products at up to 15.6% (w/w) and 88.7% (w/w), respectively. The findings suggest that non-catalytic hydrothermal deconstruction is a viable option to process and manage PPE waste.

Disturbed Gut-Liver axis indicating oral exposure to polystyrene microplastic potentially increases the risk of insulin resistance

Human uptake abundance of microplastics via various pathways, and they accumulate in human liver, kidney, gut and even placenta (especially with a diameter of 1 μm or less). Recent scientific studies have found that exposure to microplastics causes intestinal inflammation and liver metabolic disorder, but it remains largely unknown that whether the damage and inflammation may cause further development of severe diseases. In this study, we discovered one of such potential diseases that may be induced by the exposure to small-sized microplastics (with a diameter of 1 μm) performing a multi-organ and multi-omics study comprising metabolomics and microbiome approaches. Unlike other animal experiments, the dosing strategy was applied in mice according to the daily exposure of the highly exposed population, which was more environmentally relevant and reflective of real-world human exposure. Our studies on the gut-liver axis metabolism have shown that the crosstalk between the gut and liver ultimately leaded to insulin resistance and even diabetes. We proactively verified this hypothesis by measuring the levels of fasting blood glucose and fasting insulin, which were found significantly elevated in the mice with microplastics exposure. These results indicate the urgent need of large-scale cohort evaluation on epidemiology and prognosis of insulin resistance after microplastics exposure in future.

Targeting p-AKT/mTOR/MAP kinase signaling, NLRP3 inflammasome and apoptosis by fluvastatin with or without taxifolin mitigates gonadal dysfunction induced by bisphenol-A in male rats

Bisphenol-A (BPA) is a chemical substance that is widely used in industry for manufacturing of plastic bottles and resins. Recent reports found that BPA may mimic the effects of estrogen to a great manner that might disrupt the normal hormonal balance in the human body. Fluvastatin is an agent used for treatment of hypercholesterolemia that was proven to possess promising antioxidant ant anti-inflammatory properties. Taxifolin is a polyphenolic compound with potential antioxidant and antiestrogenic effects. The present study investigated the prospect of fluvastatin with or without taxifolin to mitigate testicular dysfunction elicited by BPA in rats. In a model of BPA-induced testicular toxicity, the hormonal profile was assessed and the testicular tissues were examined by biochemical analysis, histopathology, and immunohistochemistry. Fluvastatin with or without taxifolin improved the body weight gain, hormonal profile, testicular weight and functions, sperm characteristics, the antioxidant status, and the anti-inflammatory mechanisms together with enhancement of autophagy and suppression of the proapoptotic events induced by BPA in the testicular tissues. In addition, fluvastatin with or without taxifolin significantly mitigated the histopathological and the immunohistochemical changes induced by BPA in the testicular tissues. These desirable effects were more pronounced with fluvastatin/taxifolin combination relative to the use of each of these agents alone. In tandem, fluvastatin/taxifolin combination might counteract the pathogenic events induced by BPA in the testicular tissues which may be considered as a novel strategy for amelioration of these disorders.

Magnesium lithospermate B supplementation improved prenatal Bisphenol A exposure-induced metabolic abnormalities in male offspring

Obesity is closely linked with metabolic diseases, while life and prenatal exposure to endocrine-disrupting chemicals has been implicated in the development of obesity. Magnesium lithospermate B (MLB), an active compound of Salvia miltiorrhiza (Danshen), has beneficial effects on insulin resistance and metabolic abnormalities in diet-induced obese rodents. Since exposure to endocrine-disrupting chemical Bisphenol A (BPA) during pregnancy mimics the effects of high fat diet-induced alterations of glucose and lipid metabolism in adult male offspring, the effects of daily MLB supplementation for 4 weeks on metabolic abnormalities in rats weaning from prenatal BPA-exposed dams were investigated. BPA-exposed rats developed obesity and adiposity concurrent with hyperglycemia, hyperinsulinemia, insulin resistance, hypertriglyceridemia, and elevation of circulating glucagon and free fatty acids. Increased hepatic fatty acid synthesis and decreased fatty acid β-oxidation, activation of adipocytic adipogenesis, maturation, and lipogenesis, as well as reduction of muscular glucose uptake were demonstrated in BPA-exposed rats. The aforementioned alterations were improved by MLB supplementation. Additionally, MLB displayed negative effects on glucocorticoid receptor action and inflammation, and promoted lipolysis and thermogenesis in the adipose tissues. In conclusion, our findings suggest that MLB may be a potential therapeutic compound against metabolic diseases, including maternal exposure-induced metabolic abnormalities.

The Role of the Bisphenol A in Diabetes and Obesity

Bisphenol A is a compound commonly found in products meant for daily use. It was one of the first compounds to be identified as an endocrine disruptor that was capable of disrupting the endocrine system and producing very similar effects to those of metabolic syndrome. It has recently gained popularity in the scientific arena as a risk factor for obesity and diabetes due to its ability to imitate natural oestrogens and bind to their receptors. The aim was to study the possible relationship between the Bisphenol A endocrine disruptor with diabetes and obesity. The analysis of the articles allows us to conclude that Bisphenol A is an additional risk factor to consider in the development of diabetes and obesity, since it is capable of stimulating the hypertrophy of adipocytes and altering the endocrine system by mimicking the effects of the oestrogen molecule, since epidemiological studies carried out have suggested that the same disruptions seen in experimental studies on animals can be found in humans; however, despite many countries having developed policies to limit exposure to this disruptor in their populations, there is a lack of international agreement. Understanding its relationship with obesity and diabetes will help to raise awareness in the population and adopt public health campaigns to prevent exposure-especially among young people-to these substances.

Antioxidative Molecules in Human Milk and Environmental Contaminants

Breastfeeding provides overall beneficial health to the mother-child dyad and is universally recognized as the preferred feeding mode for infants up to 6-months and beyond. Human milk provides immuno-protection and supplies nutrients and bioactive compounds whose concentrations vary with lactation stage. Environmental and dietary factors potentially lead to excessive chemical exposure in critical windows of development such as neonatal life, including lactation. This review discusses current knowledge on these environmental and dietary contaminants and summarizes the known effects of these chemicals in human milk, taking into account the protective presence of antioxidative molecules. Particular attention is given to short- and long-term effects of these contaminants, considering their role as endocrine disruptors and potential epigenetic modulators. Finally, we identify knowledge gaps and indicate potential future research directions.

Environmentally Relevant Concentration of Bisphenol S Shows Slight Effects on SIHUMIx

Bisphenol S (BPS) is an industrial chemical used in the process of polymerization of polycarbonate plastics and epoxy resins and thus can be found in various plastic products and thermal papers. The microbiota disrupting effect of BPS on the community structure of the microbiome has already been reported, but little is known on how BPS affects bacterial activity and function. To analyze these effects, we cultivated the simplified human intestinal microbiota (SIHUMIx) in bioreactors at a concentration of 45 µM BPS. By determining biomass, growth of SIHUMIx was followed but no differences during BPS exposure were observed. To validate if the membrane composition was affected, fatty acid methyl esters (FAMEs) profiles were compared. Changes in the individual membrane fatty acid composition could not been described; however, the saturation level of the membranes slightly increased during BPS exposure. By applying targeted metabolomics to quantify short-chain fatty acids (SCFA), it was shown that the activity of SIHUMIx was unaffected. Metaproteomics revealed temporal effect on the community structure and function, showing that BPS has minor effects on the structure or functionality of SIHUMIx.

Insights into the interactions of bisphenol and phthalate compounds with unamended and carnitine-amended montmorillonite clays

Montmorillonite clays could be promising sorbents to mitigate toxic compound exposures. Bisphenols A (BPA) and S (BPS) as well as phthalates, dibutyl phthalate (DBP) and di-2-ethylhexyl phthalate (DEHP), are ubiquitous environmental contaminants linked to adverse health effects. Here, we combined computational and experimental methods to investigate the ability of montmorillonite clays to sorb these compounds. Molecular dynamics simulations predicted that parent, unamended, clay has higher binding propensity for BPA and BPS than for DBP and DEHP; carnitine-amended clay improved BPA and BPS binding, through carnitine simultaneously anchoring to the clay through its quaternary ammonium cation and forming hydrogen bonds with BPA and BPS. Experimental isothermal analysis confirmed that carnitine-amended clay has enhanced BPA binding capacity, affinity and enthalpy. Our studies demonstrate how computational and experimental methods, combined, can characterize clay binding and sorption of toxic compounds, paving the way for future investigation of clays to reduce BPA and BPS exposure.

Plastics derived endocrine-disrupting compounds and their effects on early development

Despite the fact that the estrogenic effects of bisphenols were first described 80 years ago, recent data about its potential negative impact on birth outcome parameters raises a strong rationale to investigate further. The adverse health effects of plastics recommend to measure the impacts of endocrine-disrupting compounds (EDCs) such as bisphenols (BPA, BPS, BPF), bis(2-ethylhexyl) phthalate, and dibutyl phthalate (DBP) in human health. Exposure to these compounds in utero may program the diseases of the testis, prostate, kidney and abnormalities in the immune system, and cause tumors, uterine hemorrhage during pregnancy and polycystic ovary. These compounds also control the processes of epigenetic transgenerational inheritance of adult-onset diseases by modulating DNA methylation and epimutations in reproductive cells. The early developmental stage is the most susceptible window for developmental and genomic programming. The critical stages of the events for a normal human birth lie between the many transitions occurring between spermatogenesis, egg fertilization and the fully formed fetus. As the cells begin to grow and differentiate, there are critical balances of hormones, and protein synthesis. Data are emerging on how these plastic-derived compounds affect embryogenesis, placentation and feto-placental development since pregnant women and unborn fetuses are often exposed to these factors during preconception and throughout gestation. Impaired early development that ultimately influences fetal outcomes is at the center of many developmental disorders and contributes an independent risk factor for adult chronic diseases. This review will summarize the current status on the impact of exposure to plastic derived EDCs on the growth, gene expression, epigenetic and angiogenic activities of the early fetal development process and their possible effects on birth outcomes.

The impacts of intrauterine Bisphenol A exposure on pregnancy and expression of miRNAs related to heart development and diseases in animal model

This study aimed to examine the impact of BPA exposure on pregnancy and foetuses on cardiac tissues and the expression of cardiac microRNAs (miRNAs) related to heart development and diseases. Pregnancy is known to be the "critical windows" in determining the offspring physical and cells development in their life after birth. The increment of the risk of cardiovascular disease (CVD) in a later stage of life has been reported by few studies demonstrated from prenatal exposure of BPA. BPA has been shown to alter miRNAs expression profiles for organ development, regeneration and metabolic functions. These alterations have been associated with the risk of CVDs. However, the associations between pregnancy outcomes and miRNAs expression in cardiac of mother- and foetuses-exposed to BPA are still not entirely explored. In BPA-exposed pregnant rat groups, a significant weight gained was observed in comparison to control (p < 0.05). Interestingly, significant changes in systolic and diastolic blood pressure between the first and third trimester of BPA-exposed pregnant rats were also observed (p < 0.05). In BPA-exposed pregnant rats, miR-499-5p was significantly altered in the heart (p < 0.01). Meanwhile, altered miR-17-5p, -208-3p, and -210-3p expressions were observed in all heart of the foetuses from BPA-exposed pregnant rats (p < 0.05). In H&E staining, BPA-exposed foetal hearts showed a sign of fibrosis while BPA-exposed pregnant rats showed muscle remnant. Masson trichrome staining further confirmed the presence of fibrosis observed in BPA-exposed foetal heart and reduced expression of cardiac troponin I (cTnI) was also observed in BPA-exposed foetal heart. In summary, altered cardiac miRNAs with histological changes were observed in both mother- and foetus-exposed BPA These findings put forward the importance of future work to further understand how prenatal BPA exposure affect foetuses in their later stage of life.

Molecular modelling methods in food safety: Bisphenols as case study

Bisphenol A (BPA), a synthetic compound widely used as a building block for polycarbonate plastics, has been declared in the European Union (EU) as a substance of very high concern (SVHC). A series of BPA alternatives and derivatives (bisphenols/BPs) with similar physical-chemical properties have been produced and used by companies for substituting it. To evaluate the estrogenic and androgenic binding activity of 26 BPs, a non-statistical in silico approach has been applied. The results of molecular docking analyses applied on six different nuclear receptors (NRs) have revealed that: i) some BPA metabolites could lower the harmful effects of BPA exposure; ii) BPS is a lower interactor for all NRs, but it does not appear safer at all for androgen receptor (AR), for which its binding activity is found similar to a pharmacological anti-androgen; iii) only a BP has been found as a safer compound for all NRs considered. Moreover, molecular dynamic simulation of three BPs on ERα have revealed that the presence of negative hydrophobic interactions could induce a decrease in receptor activity. Overall, the present results demonstrate that in silico methods could be a valid approach to screen estrogenic and androgenic activity of food contact materials (FCMs).

Bisphenol A triggers axonal injury and myelin degeneration with concomitant neurobehavioral toxicity in C57BL/6J male mice

Bisphenol A (BPA) is a ubiquitously distributed endocrine disrupting chemical (EDC). BPA exposure in humans has been a matter of concern due to its increased application in the products of day to day use. BPA has been reported to cause toxicity in almost all the vital organ systems even at a very low dose levels. It crosses the blood brain barrier and causes neurotoxicity. We studied the effect of BPA on the cerebral cortex of C57BL/6J mice and examined whether BPA exposure alters the expression of axonal and myelin structural proteins. Male mice were dosed orally to 40 μg and 400 μg BPA/kg body weight for 60 days. BPA exposure resulted in memory loss, muscle coordination deficits and allodynia. BPA exposure also caused degeneration of immature and mature oligodendrocytes as evaluated by decreased mRNA levels of 2',3'-cyclic nucleotide 3' phosphodiesterase (CNPase), nestin, myelin basic protein (MBP) and myelin-associated glycoprotein-1 (MAG-1) genes revealing myelin related pathology. It was observed that subchronic BPA exposure caused neuroinflammation through deregulation of inflammatory cytokines mRNA and protein expression which further resulted into neurotoxicity through axonal as well as myelin degeneration in the brain. BPA also caused increased oxidative stress in the brain. Our study indicates long-term subchronic low dose exposure to BPA has the potential to cause axonal degeneration and demyelination in the oligodendrocytes and neurons which may have implications in neurological and neuropsychological disorders including multiple sclerosis (MS), neuromyelitis optica and others.

Endocrine disrupting chemicals: Impact on human health, wildlife and the environment

Endocrine disrupting chemicals are a group of pollutants that can affect the endocrine system and lead to diseases and dysfunctions across the lifespan of organisms. They are omnipresent. They are in the air we breathe, in the food we eat and in the water we drink. They can be found in our everyday lives through personal care products, household cleaning products, furniture and in children's toys. Every year, hundreds of new chemicals are produced and released onto the market without being tested, and they reach our bodies through everyday products. Permanent exposure to those chemicals may intensify or even become the main cause for the development of diseases such as type 2 diabetes, obesity, cardiovascular diseases and certain types of cancer. In recent years, legislation and regulations have been implemented, which aim to control the release of potentially adverse endocrine disrupting chemicals, often invoking the precautionary principle. The objective of this review is to provide an overview of research on environmental aspects of endocrine disrupting chemicals and their effects on human health, based on evidence from animal and human studies. Emphasis is given to three ubiquitous and persistent groups of chemicals, polychlorinated biphenyls, polybrominated diphenyl ethers and organochlorine pesticides, and on two non-persistent, but ubiquitous, bisphenol A and phthalates. Some selected historical cases are also presented and successful cases of regulation and legislation described. These led to a decrease in exposure and consequent minimization of the effects of these compounds. Recommendations from experts on this field, World Health Organization, scientific reports and from the Endocrine Society are included.

Exposure to Bisphenol a Substitutes and Gestational Diabetes Mellitus: A Prospective Cohort Study in China

Background: The association of bisphenol A (BPA) and gestational diabetes mellitus (GDM) has been investigated in only a small number of studies, and research on the associations between BPA substitutes and GDM is scarce. Objective: We aimed to investigate the associations of four bisphenols [bisphenol A (BPA), bisphenol S (BPS), bisphenol F (BPF), and bisphenol AF (BPAF)] levels in urine sample with the risk of gestational diabetes mellitus (GDM) and plasma glucose levels. Methods: A total of 1,841 pregnant women from a cohort study were recruited at their first prenatal examination between 2013 and 2015 in Wuhan, China. Concentrations of four bisphenols (BPA, BPS, BPF, BPAF) were measured in first-trimester urine samples using Ultra-high performance liquid chromatography system coupled to a Triple Quadrupole mass spectrometer (UHPLC-TQMS). An oral glucose tolerance test (OGTT) was performed at 24-28 gestational weeks and GDM was diagnosed post hoc using International Association of Diabetes and Pregnancy Study Groups criteria. We used multivariable logistic regression models to examine the associations of urinary bisphenols with the risk of GDM, and multiple linear regression models to determine the associations between bisphenols exposure and plasma glucose levels. Results: Urinary BPAF was associated with increased odds of GDM among women with normal pre-pregnancy BMI [adjusted odds ratio (aOR) = 1.70 (95% CI: 1.08, 2.67) for the highest group compared to the lowest group], and the association remained significant after additional adjustment for other bisphenols [aOR = 1.68 (95% CI: 1.03, 2.72)]. No significant associations were observed for other bisphenols and GDM. Consistent with the result of GDM, women in the highest BPAF category had a mean of 0.05 mmol/L (95% CI: 0.01, 0.09) higher fasting plasma glucose (FPG) levels than women in the lowest category. For BPA and plasma glucose, non-linear associations were observed between urinary BPA and FPG and the sum of the PG z-score among women who were overweight (p for non-linear association < 0.05). We also found that the per-unit increase in natural log transformed specific gravity adjusted BPS [ln (SG-adj BPS)] was associated with a 0.03 mmol/L (95% CI: 0.01, 0.04) increase in FPG levels and the associations might be modified by fetal sex (p for interaction < 0.05). Among women with female fetus, a per-unit increase in ln (SG-adj BPS) was associated with a 0.04 mmol/L (95% CI: 0.02, 0.06) increase in FPG, a 0.11 mmol/L (95% CI: 0.04, 0.17) increase in 1 h-PG and a 0.19 mmol/L (95% CI: 0.08, 0.30) increase in the sum of PG z-score. Conclusions: Our results provide evidence that BPAF and BPS might be potential risk factors of GDM, which require to be studied further.

Testing baby bottles for the presence of residual and migrated bisphenol A

Plastic made with bisphenol A (BPA) produces trans-generational changes in genes and behavior. It has been positively linked to obesity and thyroid dysfunction. This study aimed to detect the presence of BPA in polycarbonate plastic (PC) baby bottles. Fifteen PC baby bottles with a clear indication of BPA free/safe/clear were randomly selected. High-performance liquid chromatography (HPLC) tests were used to detect residual or migrating BPA post three stress tests. An estimated intake of BPA among children was calculated then compared to the universal tolerable daily intake (TDI). Around 27% of bottles had detectable amounts of residual BPA in the first test, 100% released migrating BPA in the second and third tests. A significant positive linear trend in migrated BPA levels was observed over the three consecutive tests P < 0.0001. Approximately 73.5% of the accounted variability in BPA levels was due to these stress tests P < 0.0001. Babies from 0 to 3 months are expected to consume 0.8 to 23.8% of their safe TDI of BPA just by using plastic bottles between the first time of usage and after 60 washes (estimated 15 to 20 days of usage). Although no bottles have shown a risk of BPA intake exceeding TDI, the combined use of BPA bottles with other plastic utensils might result in reaching it. It is advisable to refrain from using BPA-containing plastic bottles or be cautious about usage duration. Manufacturers should indicate a clear margin of usage duration. Four baby bottle brands showed the least BPA leaking (Baby King, Camera, Sweet Baby, and Farlin).

Bisphenol-A impairs cellular function and alters DNA methylation of stress pathway genes in first trimester trophoblast cells

Humans are exposed to Bisphenol A (BPA) from the consumer products and plastic substances. However, impacts of low levels of BPA exposure on placental developmental processes such as first trimester trophoblast cell growth, angiogenesis and epigenetic modifications are not well studied. Low concentration of BPA (1 nM) affected cell proliferation of human placental first trimester trophoblasts using a model cell, HTR8/SVneo. BPA abolished both basal- and vascular endothelial growth factor (VEGF)-stimulated tube formation in these cells. BPA significantly down regulated mRNA expression of VEGF, proliferating cell nuclear antigen, intercellular adhesion molecule 1 with concomitant upregulation of 11-β-hydroxysteroid dehydrogenase 2 mRNA and protein expression in HTR8/SVneo cells. BPA also lowered CpG methylation of gene promoter associated with metabolic and oxidative stress. This study demonstrated that BPA at 1 nM not only affected cellular growth, development and angiogenic activities but also affected DNA methylation of stress response and down-regulation of angiogenic growth factors in first trimester trophoblast cells.

Effects of Bisphenol-A on proliferation and expression of genes related to synthesis of polyamines, interferon tau and insulin-like growth factor 2 by ovine trophectoderm cells

This study evaluated the effects of bisphenol A (BPA) on proliferation of ovine trophectoderm (oTr1) cells, as well as expression of genes for transport of arginine and synthesis of polyamines. BPA reduced proliferation of oTr1 cells at concentrations of 1 × 10^-6, 1 × 10^-5, 1 × 10^-4 M compared to concentrations of 0, 1 × 10^-9, and 1 × 10^-8 M at 24 and 96 h of culture. Lower concentrations of BPA significantly increased expression of mRNAs for agmatinase (AGMAT), arginine decarboxylase (ADC), ornithine decarboxylase (ODC1) and solute carrier family 7 member 1 (SLC7A1). Similarly, synthesis of polyamines by oTr1 cells was greatest at lower concentrations of BPA and decreased as the dose of BPA increased. Expression of mRNAs for interferon tau (IFNT) and insulin-like growth factor 2 (IGF2) by oTr1 cells was greater than for controls at 1 × 10^-9 M BPA. Overall, the effects of BPA on proliferation and gene expression by oTr1 cells were highly dose-dependent.

Toxic Effects of Bisphenol A, Propyl Paraben, and Triclosan on Caenorhabditis elegans

Bisphenol A (BPA) is a ubiquitous plasticizer which is absorbed by ingestion and dermal contact; propyl paraben (PPB) inhibits the microbiome and extends the shelf life of many personal care products, whereas triclosan (TCS) is commonly found in antiseptics, disinfectants, or additives. In this work, Caenorhabditis elegans was used as a biological model to assess the toxic effects of BPA, PPB, and TCS. The wild type strain, Bristol N2, was used in bioassays with the endpoints of lethality, growth, and reproduction; green fluorescent protein (GFP) transgenic strains with the hsp-3, hsp-4, hsp-16.2, hsp-70, sod-1, sod-4, cyp-35A4, cyp-29A2, and skn-1 genes were evaluated for their mRNA expression through fluorescence measurement; and quick Oil Red O (q ORO) was utilized to stain lipid deposits. Lethality was concentration-dependent, while TCS and PPB showed more toxicity than BPA. BPA augmented worm length, while PPB reduced it. All toxicants moderately increased the width and the width–length ratio. BPA and PPB promoted reproduction, in contrast to TCS, which diminished it. All toxicants affected the mRNA expression of genes related to cellular stress, control of reactive oxygen species, and nuclear receptor activation. Lipid accumulation occurred in exposed worms. In conclusion, BPA, PPB, and TCS alter the physiology of growth, lipid accumulation, and reproduction in C. elegans, most likely through oxidative stress mechanisms.