In vivo effects of bisphenol A in laboratory rodent studies

Multi-omics analysis reveals BPF exposure causes hepatic glucose and lipid metabolism disorder in rats by disrupting energy homeostasis

Bisphenol F (BPF) is one of the main substitutes for Bisphenol A (BPA) and is widely used in the manufacture of household products. In addition, BPF threatens human health through environmental pollution and the food chain. However, the hepatotoxicity of BPF and its effects on glucose and lipid metabolism remain unclear. This study used male SD rats as an animal model to investigate the hepatotoxicity of BPF and its effects on glucose and lipid metabolism. The results of the HE staining, serum and liver biochemical indicators show that BPF can damage the basic structure of the liver, cause liver dysfunction and lead to disorders of liver glucose metabolism and lipid metabolism. Furthermore, we conducted metabolomics and proteomics analyses on the livers of the BPF exposed group at 100 mg/kg/d in comparison with the control group. The results indicated that BPF exposure had a significant effect on liver metabolism. Combined with biological analysis and the validation of changes in genes and proteins related to glucose and lipid metabolism in the liver, it was elucidated that BPF can promote fatty acid oxidation and inhibit fatty acid synthesis through the AMPK and PPAR signaling pathways, leading to a reduction in fatty acids. Furthermore, it has been demonstrated that BPF can promote glycogen synthesis and gluconeogenesis via the AKT pathway, which can result in disorders of glucose metabolism.

Bisphenol compounds in female underwear manufactured in China and their potential risks to women's health

Currently, there is limited information regarding the presence of chemicals in female underwear and the potential risks involved. This study investigated the levels of ten bisphenols in brassieres and briefs made in China, revealing total concentrations ranging from 13.9 to 52,967 ng/g. Bisphenol S (BPS), bisphenol F (BPF), and bisphenol A (BPA) made up a median of 53.2 %, 24.4 %, and 22.2 % of the total concentrations, respectively. The concentrations of bisphenols were significantly higher in darker samples compared to most other colors. When compared to previous reports on other textiles, this study found similar levels of BPA but higher concentrations of BPF and BPS. Furthermore, the median migration rates of BPF (39.1 %) and BPS (25.2 %) in artificial sweat were significantly greater than that of BPA (6.58 %), leading to higher exposure levels for BPF and BPS. The estimated non-carcinogenic risks associated with the three primary bisphenols in the underwear were deemed acceptable. However, the estimated exposure to BPS and BPF from this source represented about 2.53-12.0 % and 11.8-38.2 % of total human exposure, respectively, suggesting that the contamination of these chemicals in underwear is a concern that should not be overlooked.

Ancestral bisphenol A exposure led to non-alcoholic fatty liver disease and sex-specific alterations in proline and bile metabolism pathways in the liver

Endocrine-disrupting chemicals can induce metabolic alterations, resulting in diseases such as obesity, diabetes, and fatty liver disease, which can be inherited by offspring inhabiting uncontaminated environments. Bisphenol A (BPA), a well-known endocrine disruptor, can induce endocrine disruption, leading to metabolic disorders in subsequent generations without further exposure to BPA via nongenetic transgenerational inheritance. Using medaka as an animal model, we reported that ancestral BPA exposure leads to transgenerational nonalcoholic fatty liver disease (NAFLD) in grandchildren four generations after the initial exposure. It is unclear if transgenerational NAFLD developed because ancestral BPA exposure differs from that developed due to direct and continuous BPA exposure because the transgenerational disease develops in the absence of the stressor. We induced transgenerational NAFLD in medaka with ancestral BPA exposure (10 µg/L) at the F0 generation and examined transcriptional and metabolomic alterations in the liver of the F4 generation fish that continued to develop NAFLD. To understand the etiology of NAFLD in unexposed generations, we performed nontargeted liquid chromatography-mass spectrometry-based metabolomic analysis in combination with bulk RNA sequencing and determined biomarkers, co-expressed gene networks, and sex-specific pathways triggered in the liver. An integrated analysis of metabolomic and transcriptional alterations revealed a positive association with the severity of the NAFLD disease phenotype. Females showed increased NAFLD severity and had metabolic disruption involving proline metabolism, tryptophan metabolism, and bile metabolism pathways. The present results provide the transcriptional and metabolomic underpinning of metabolic disruption caused by ancestral BPA exposure, providing avenues for further research to understand the development and progression of transgenerational NAFLD caused by ancestral bisphenol A exposure.

Mechanistic insights into the P-coumaric acid protection against bisphenol A-induced hepatotoxicity in in vivo and in silico models

Bisphenol A (BPA), commonly found in plastic containers and epoxy resins used for food products, presents substantial health risks, particularly in relation to hepatic toxicity. This study investigates BPA-induced liver damage and explores the mechanistic dose-dependent protective effects of P-coumaric acid (PCA). 50 male rats were divided into control, BPA-treated, BPA + PCA50, BPA + PCA100, and PCA100 groups. BPA exposure for 14 days induced oxidative stress, evidenced by elevated malondialdehyde levels and decreased activities of antioxidant enzymes (superoxide dismutase, glutathione peroxidase, and catalase). Higher doses of PCA effectively mitigated these effects by restoring redox balance and enhancing antioxidant enzyme activities. Additionally, BPA disrupted inflammation and apoptosis pathways, inhibiting anti-inflammatory markers and interfering with the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) pathway. PCA exhibited dose-dependent protection against these disruptions. Computational analyses revealed that BPA inhibits cyclooxygenase-1 through stable hydrogen bonding with threonine at position 322. PCA's dual protective effect was confirmed by attenuating inflammatory pathways, including TNF-α inhibition and suppression of the Kelch-like ECH-associated protein 1 (KEAP1) and Nrf2 signaling pathway. Histopathological assessments confirmed that PCA alleviated significant hepatic damage induced by BPA. Immunohistochemical and immunofluorescence analyses further supported PCA's protective role against BPA-induced apoptosis and cellular hepatotoxicity. These findings underscore PCA's protective potential against BPA-induced hepatotoxicity and highlight novel mechanistic interactions that warrant further investigation in applied nutritional biochemistry.

Prenatal bisphenol A exposure causes sperm quality and functional defects via Leydig cell impairment and meiosis arrest in mice offspring

Bisphenol A (BPA), widely used in plastic production, acts as an environmental endocrine disruptor which is harmful to male reproductive health. However, the specific mechanisms through which prenatal BPA exposure disrupts spermatogenesis in offspring, particularly in terms of Leydig cell dysfunction and meiotic progression, remain poorly understood. To address this gap, we constructed a mouse model with BPA lowest Observed Adverse Effect Level (LOAEL: 50 mg/kg bw/day) exposure from embryonic day (ED) 0.5 to 18.5. Our results demonstrated that prenatal BPA exposure significantly decreased serum testosterone levels, testis weight, sperm count, motility parameters, and acrosomal integrity. Furthermore, it arrested the meiotic transition from zygotene to pachytene spermatocytes, leading to reduced sperm fertility characterized by reduced sperm-egg binding capacity and abnormal early embryonic cleavage in the male offspring. Importantly, prenatal BPA exposure significantly reduced the expression of PCNA (a marker of germ cell proliferation), SYCP3 (a meiosis regulator), and Vimentin (a blood-testis barrier component), collectively indicating impaired spermatogenesis in offspring testes. Additionally, prenatal BPA exposure dramatically reduced Leydig cell numbers and increased apoptosis, marked by BAX/BCL2 up-regulation, which mechanistically explains the observed testosterone reduction. In vitro experiments corroborated these effects: BPA exposure concentration-dependently inhibited Leydig cell proliferation, induced G0/G1 phase arrest, and downregulated testosterone synthesis molecules (Hsd3b1, Hsd17b3, Star, Cyp11a1, Cyp17a1). Quantitative proteomics identified 234 differentially expressed proteins (97 downregulated, 137 upregulated) in BPA-exposed Leydig cells. Bioinformatics analysis revealed that down-regulated proteins were mainly related to steroid hormone receptor activity, estrogen response element binding, and centrosome duplication processes, while the up-regulated proteins were mainly involved in oxygen binding and ROS metabolic process. Conclusively, prenatal BPA exposure impaired offspring male fertility via multi-faceted mechanisms: sperm quality defects, steroidogenic disruption, and meiotic arrest. This study advances the understanding of BPA transgenerational reproductive toxicity and underscores the need to mitigate prenatal exposure risks.

Ferulic acid ameliorates bisphenol A (BPA)-induced Alzheimer's disease-like pathology through Akt-ERK crosstalk pathway in male rats

OBJECTIVES

This study investigated the neuroprotective effect of ferulic acid (FA) against bisphenol A (BPA) induced Alzheimer's disease-like pathology in male rats.

METHODS

Rats were allocated into four groups, control, BPA, BPA + FA, and FA, respectively, for 40 days. Spatial working memory and recognition memory were evaluated. Moreover, the brain levels of oxidative stress biomarkers, proinflammatory cytokines, extracellular signal-regulated kinase (ERK), and phosphorylated serine/threonine protein kinase (p-Akt) were measured. We also determined the brain neuropathological protein levels, including Beta-Amyloid 1-42, total Tau (tTau), and phosphorylated Tau (pTau) proteins. Furthermore, brain levels of Acetylcholinesterase (AChE) and Beta-secretase (BACE) were assessed. Brain histological investigation and immunohistochemistry determination of glial fibrillar acidic protein (GFAP) were also performed. Moreover, docking simulation was adapted to understand the inhibitory role of FA on AChE, BACE-1, and ERK1/2.

RESULTS

Interestingly, the BPA + FA treated group showed a reversal in the cognitive impairments induced by BPA, which was associated with improved brain redox status. They also exhibited a significant decrease in brain inflammatory cytokines, ERK, and p-Akt levels. Moreover, they revealed a decline in beta-amyloid 1-42 and a significant improvement in tTau expression and pTau protein levels in the brain tissue. Further, the brain levels of AChE and BACE were substantially reduced in BPA + FA rats. The neuroprotective effect of FA was confirmed by restoring the normal architecture of brain tissue, which was associated with decreasing GFAP.

CONCLUSION

FA could be a potent neuroprotectant agent against AD with a possible prospect for its therapeutic capabilities and nutritional supplement value due to its antioxidant and antiapoptotic properties.

In Vivo Investigation of the Effects of Nonylphenol on the Pituitary-Adrenal Axis and Pineal Gland in Male Rats

The pineal gland secretes melatonin, which regulates various physiological processes; damage to this gland disrupts these functions. This study aimed to investigate the effect of nonylphenol on the pineal gland and the pituitary-adrenal axis, which is associated with this system. The study was initiated using Wistar albino male rats on their postnatal 21st day, a critical developmental stage for endocrine regulation. Nonylphenol was administered via oral gavage at doses of 5, 25 and 125 mg/kg/day, while bisphenol-A was given at 50 mg/kg/day as a positive control. At the end of the treatment period, liver, kidney, pituitary, pineal and adrenal tissues were examined histopathologically. Hormone levels were analysed in serum samples. Significant changes in adrenocorticotropic hormone, melatonin and aldosterone levels were detected in hormone analyses. In contrast, no differences in corticosterone and glucose levels were detected. Histopathological findings showed structural changes in tissues. The effects of nonylphenol on the pituitary-adrenal axis and melatonin vary depending on the experimental protocols employed. However, it is clear that nonylphenol and bisphenol A have negative effects on the pituitary-adrenal axis, pineal gland, liver and kidney. In conclusion, future research should focus on elucidating the molecular mechanisms underlying these effects and developing environmentally friendly strategies to eliminate nonylphenol and bisphenol-A contamination.

Prenatal bisphenol A and/or diethylhexyl phthalate exposure followed by adult estradiol treatment affects behavior and brain monoamines in female rat offspring

Significance

Women are at increased risk for mood disorders, which may be partly attributed to exposure to endocrine-disrupting chemicals (EDCs) during sensitive periods such as pregnancy. Exposure during these times can impact brain development in the offspring, potentially leading to mood disorders in later life. Additionally, fluctuating levels of endogenous estrogens, as seen during pregnancy, or the use of oral contraceptives, can further elevate this risk. This study examines the cumulative effects of prenatal EDC exposure combined with chronic low-dose 17β-estradiol (E2) treatment in adulthood on neurobehavioral outcomes.

Methods

Pregnant Sprague-Dawley rats were orally dosed with vehicle, bisphenol A (BPA) (5 μg/kg body weight (BW)/day), low-dose (LD) diethylhexyl phthalate (DEHP) (5 μg/kg BW/day), high-dose (HD) DEHP (7.5 mg/kg BW/day), or a combination of the two (BPA+DEHP) from gestational days 6-21. At 3 months of age, female offspring were implanted with slow-release E2 pellets or were sham-implanted. Following a 90-day treatment period, behavioral testing was conducted, and serum hormones and brain monoamine levels were analyzed.

Results

Chronic E2 treatment in controls increased anxiety and reduced active coping behaviors. In DEHP- and BPA+DEHP-exposed offspring, E2 treatment reversed some of these effects. Dose-dependent alterations in circulating hormone levels and brain monoamines were observed. Dysregulation of the stress axis was particularly notable with the higher dose of DEHP.

Conclusions

Overall, prenatal EDC exposure altered behavior, hormones, and brain monoamines, with adult E2 treatment further exacerbating some of these effects in female offspring.

Assessment of bisphenol accumulation from disposable devices used sequentially in IVF routine procedures

RESEARCH QUESTION

Are bisphenols released from disposable devices used in assisted reproductive technology (ART) procedures, and do they accumulate when several disposable devices are used sequentially under routine conditions?

DESIGN

A comprehensive assessment of 19 individual disposable devices (31 assessments) and nine combinations of disposable devices replicating the main steps in an ART procedure was undertaken. The extraction of bisphenols followed routine-use conditions (temperature and duration). The concentrations of 10 bisphenols were determined using online solid-phase extraction/liquid chromatography/mass spectrometry methodology.

RESULTS

Bisphenol S (BPS) was quantified consistently from 100-mm culture dishes (32 ± 20 pg) and from high security sperm straws (3 ± 1 pg). Also, BPS and bisphenol A (BPA) were quantified consistently from spermicide-free condoms (95 ± 78 and 83 ± 49 pg, respectively). No other bisphenols were detected in disposable devices when tested individually. When disposable devices were used in combination, both BPA and BPS were detected consistently in combinations of 13 disposable devices mimicking sperm collection in a condom and its preparation (46 ± 16 and 43 ± 32 pg, respectively). BPS was quantified consistently in combinations of 14 disposable devices mimicking sperm collection, its preparation and freezing (10 ± 4 pg), and in combinations of 17 disposable devices mimicking oocyte retrieval (37 ± 22 pg).

CONCLUSIONS

BPA and BPS are released in small quantities from some disposable devices used in routine conditions during ART procedures, but do not appear to accumulate when these disposable devices are used in combination.

Effect of Endocrine Disruptors on Testicular Function

Several classes of exogenous chemicals interfere with the endocrine system and disrupt the normal functioning of hormones, leading to a wide range of adverse health effects. The male reproductive system is particularly vulnerable to endocrine disruption, as it involves complex interactions between endocrine, paracrine, and autocrine signals that regulate spermatogenesis and steroidogenesis within the testes. Exposure to endocrine disruptors (EDs) has been associated with reduced semen quality, including decreased sperm concentration, motility, and morphology. Some endocrine disruptors have also been linked to alterations in testosterone levels, which impact overall male reproductive health. Bisphenol A, phthalates, dioxins, polychlorinated biphenyls, organophosphate pesticides, and phytoestrogens are well-known endocrine disruptors that interfere with male reproductive functions. Furthermore, these substances have been associated with an increased risk of reproductive disorders such as cryptorchidism, hypospadias, and testicular cancer. Due to the presence of endocrine-disrupting chemicals in numerous consumer goods and personal care products, people encounter these harmful substances through ingestion, absorption, inhalation, and skin contact. However, the duration of exposure to a particular endocrine disruptor or exposure during a particular stage of development is the determining factor for testicular function. This chapter provides a comprehensive overview of the effects of endocrine disruptors on testicular function, from molecular mechanisms to clinical outcomes.

Impact of bisphenol A and analogues eluted from resin-based dental materials on cellular and molecular processes: An insight on underlying toxicity mechanisms

Dental resin systems, used for artificial replacement of teeth and their surrounding structures, have gained popularity due to the Food and Drug Administration's (FDA) recommendation to reduce dental amalgam use in high-risk populations and medical circumstances. Bisphenol A (BPA), an endocrine-disrupting chemical, is an essential monomer within dental resin in the form of various analogues and derivatives. Leaching of monomers from resins results in toxicity, affecting hormone metabolism and causing long-term health risks. Understanding cellular-level toxicity profiles of bisphenol derivatives is crucial for conducting toxicity studies in in vivo models. This review provides insights into the unique expression patterns of BPA and its analogues among different cell types and their underlying toxicity mechanisms. Lack of a consistent cell line for toxic effects necessitates exploring various cell lines. Among the individual monomers, BisGMA was found to be the most toxic; however, BisDMA and BADGE generates BPA endogenously and found to elicit severe adverse reactions. In correlating in vitro data with in vivo findings, further research is necessary to classify the elutes as human carcinogens or xenoestrogens. Though the basic mechanisms underlying toxicity were believed to be the production of intracellular reactive oxygen species and a corresponding decline in glutathione levels, several underlying mechanisms were identified to stimulate cellular responses at low concentrations. The review calls for further research to assess the synergistic interactions of co-monomers and other components in dental resins. The review emphasizes the clinical relevance of these findings, highlighting the necessity for safer dental materials and underscoring the potential health risks associated with current dental resin systems.

Natural Eutectic Solvent-Based Temperature-Controlled Liquid-Liquid Microextraction and Nano-Liquid Chromatography for the Analysis of Herbal Aqueous Samples

In this work, two novel (-)-menthol-based hydrophobic natural eutectic solvents with vanillin and cinnamic acid were prepared and applied as extraction solvents. In this regard, 12 endocrine disruptors, including phenol, 2,4-dimethylphenol, 2,3,6-trimethylphenol, 4-tert-butylphenol, 4-sec-butylphenol, 4-tert-amylphenol, 4-n-hexylphenol, 4-tert-octylphenol, 4-n-heptylphenol, 4-n-octylphenol, and 4-n-nonylphenol and bisphenol A, were studied in a green tea drink. A temperature-controlled liquid-liquid microextraction was used as the extraction method, and nano-liquid chromatography-ultraviolet detection was used as the separation and determination system. Different parameters affecting the compatibility of the non-ionic eutectic solvents with water-polar organic solvent mixtures and chromatographic and detection systems were optimized, including injection/dilution solvent, injection mode, mobile phase composition, and step gradient. With the same purpose, two stationary phases were tested, including XBridge® C18 and a mixed-phase Cogent C30-XBridge® C18. Finally, the greenness and blueness of the methodology were assessed to evaluate the environmental profile and usability of the procedure.

Modification of Light-Cured Composition for Permanent Dental Fillings; Mass Stability of New Composites Containing Quinoline and Quinoxaline Derivatives in Solutions Simulating the Oral Cavity Environment

Billions of patients struggle with dental diseases every year. These mainly comprise caries and related diseases. This results in an extremely high demand for innovative, polymer composite filling materials that meet a number of dental requirements. The aim of the study was to modify the light-cured composition of permanent dental fillings by changing the composition of the liquid organic matrix. New photoinitiators (DQ1-DQ5) based on a quinoline or quinoxaline skeleton and a co-initiator-(phenylthio)acetic acid (PhTAA) were used. In addition, monomers that have been traditionally used in dental materials were replaced by trimethylolpropane triacrylate (TMPTA). The neutral dental glass IDG functioned as an inorganic filler. The influence of the storage conditions of the developed composites in solutions simulating the natural oral environment during the consumption of different meals on sorption, solubility, and mass changes was assessed. For the tests, fifty-four cylindrical composite samples were prepared according to ISO 4049 guidelines and stored in different solutions. Distilled water, artificial saliva, heptane, 10% ethanol, and 3% acetic acid, as well as solutions containing pigments such as coffee, tea, red wine, and Coca-Cola, were used for the studies. The samples were stored in these solutions for 7, 14, 28, 35, 42, 49, 56, and 63 days at 37 °C. The sorption, solubility, and mass changes in the tested samples were determined, and the trend of these changes as a function of storage time was presented. The results were analyzed considering the nature of the solution used, i.e., aqueous, hydrophobic, and acidic. The properties evaluated changed in a different way, characteristic for each of the abovementioned solution groups. It was found that the type of solution simulating the natural environment of the oral cavity has the greatest influence on the sorption, solubility, and changes in the mass of the tested material.

Ultrasound-assisted bisphenol AF degradation using in situ generated hydrogen peroxide

Bisphenol AF (BPAF) is degraded through the ultrasound-assisted in situ generation and activation of hydrogen peroxide (H2O2) by the copper(II) catalysed oxidation of hydroxylamine (NH2OH) with dioxygen (O2). Compared to added H2O2, in situ generated H2O2 significantly improves the degradation of BPAF from 46.7% to 94.8% in ∼15 min. The reaction follows a pseudo-first-order kinetic model. This study examines the influence of solution pH, anions, humic acid, and different concentrations of the reactants on BPAF degradation. Mass spectrometry was used to identify the BPAF degradation products, and a degradation pathway is proposed. This work advances the understanding of in situ hydrogen peroxide generation and activation in advanced oxidation (Fenton-like) processes (AOPs).

Bioaccessibility of plastic-related compounds from polymeric particles in marine settings: Are microplastics the principal vector of phthalate ester congeners and bisphenol A towards marine vertebrates?

Marine vertebrates are known to ingest significant amounts of microplastics (MPs). Once ingested, MPs might cause gastrointestinal injuries and serve as a path of harmful plastic components, such as phthalate esters (PAEs) and bisphenol A (BPA) in the food chain. However, there is a lack of standardized in-vitro methods capable of simulating fish uptake of chemicals from MPs in the environment as potential vectors of such contaminants. In this work, leaching and in-vitro oral bioaccessibility testing of PAEs and BPA from MPs were conducted batchwise using artificial seawater and gut fluids mimicking gastric, intestinal, and gastrointestinal compartments of marine vertebrates at physiological temperature. The environmental and physiologically relevant extraction tests were applied to medium-density polyethylene (PE) and polyvinyl chloride (PVC) certified reference materials containing eight PAEs of varying hydrophobicity, namely, dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate, benzylbutyl phthalate, diethylhexyl phthalate, di-n-octyl phthalate, diisononyl phthalate and diisodecyl phthalate, and BPA (only in PE) as MP surrogates with realistic analyte concentrations of additives for primary MPs. The analysis of the leachates/gut fluid extracts was performed via dilute-and-shoot by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Only the most hydrophilic compounds, i.e. DMP, DEP and BPA, were found to get released significantly in saline waters, and exhibited the highest oral bioaccessibility rates (34-83 %). Based on our results, a dual-compartment physiologically relevant gastrointestinal test is recommended for appropriate estimation of fish bioaccessibility. The fish daily intakes of DMP, DEP and BPA from MPs, and seawater ingestion as well were estimated using several contamination scenarios (10th percentile as the low level, 50th percentile as the medium level and 90th percentile as the high level) based on probabilistic distributions and cumulative probability curves of measured environmental concentrations of (i) MPs in seawater throughout the world, (ii) DMP, DEP and BPA in beached MPs and those sampled in the open ocean (including both incurred and adsorbed contaminants), and (iii) DMP, DEP and BPA in seawater as reported in recent literature. Under a medium-level concentration scenario (50th percentile) in marine settings, and taking the gastrointestinal bioaccessibility factor into account, the daily intake of DMP, DEP and BPA from MPs accounted for a mere 0.02 % of the waterborne contribution. Hence, the ingestion of MPs should not be considered the primary route of fish exposure to BPA and the most polar PAEs in marine environments. However, more studies on the local and the global scales for mass concentrations of MPs and additives in marine settings are needed for further confirmation of our findings.

Unravelling bisphenol A-induced hepatotoxicity: Insights into oxidative stress, inflammation, and energy dysregulation

Bisphenol A (BPA), a prevalent plastic monomer and endocrine disruptor, negatively impacts metabolic functions. This study examines the chronic effects of eco-relevant BPA concentrations on hepatotoxicity, focusing on redox balance, inflammatory response, cellular energy sensors, and metabolic homeostasis in male Swiss albino mice. Chronic BPA exposure resulted in reactive oxygen species (ROS) accumulation, altered hepatic antioxidant defense, lipid peroxidation, and NOX4 expression, leading to reduced cell viability. Additionally, BPA exposure significantly upregulated hepatic pro-inflammatory cytokine genes (Tnf-α, Il-1β, Il-6), NOS2, and arginase II, correlating with increased TLR4 expression, NF-κB phosphorylation, and a dose-dependent decrease in IκBα levels. BPA-induced NF-κB nuclear localization and inflammasome activation (NLRP3, cleaved caspase-1, IL-1β) established an inflammatory milieu. Perturbations in hepatic AMPKα phosphorylation, SIRT1, and PGC-1α, along with elevated p38 MAPK phosphorylation and ERα expression, indicated BPA-induced energy dysregulation. Furthermore, increased PLA2G4A, COX1, COX2, and PTGES2 expression in BPA-treated liver correlated with hyperlipidemia, hepatic FASN expression, steatosis, and visceral adiposity, likely due to disrupted energy sensors, oxidative stress, and inflammasome activation. Elevated liver enzymes (ALP, AST, ALT) and apoptotic markers indicated liver damage. Notably, N-acetylcysteine (NAC) priming reversed BPA-induced hepatocellular ROS accumulation, NF-κB-inflammasome activation, and intracellular lipid accumulation, while upregulating cellular energy sensors and attenuating ERα expression, suggesting NAC's protective effects against BPA-induced hepatotoxicity. Pharmacological inhibition of the NF-κB/NLRP3 cascade in BAY11-7082 pretreated, or NLRP3 immunodepleted hepatocytes reversed BPA's negative impact on SIRT1/p-AMPKα/PGC-1α and intracellular lipid accumulation, providing mechanistic insights into BPA-induced metabolic disruption.

Tissue-Engineered Oral Epithelium for Dental Material Testing: Toward In Vitro Biomimetic Models

Tissue-engineered oral epithelium (ΤΕΟΕ) was developed after comparing various culture conditions, including submerged (SUB) and air-liquid interface (ALI) human cell expansion options. Barrier formation was evaluated via transepithelial electrical resistance (TEER) and calcein permeation via spectrofluorometry. TEOE was further assessed for long-term viability via live/dead staining and development of intercellular connections via transmission electron microscopy. Tissue architecture was evaluated via histochemistry and the expression of pancytokeratin (pCK) via immunohistochemistry. The effect of two commonly used dental resinous monomers on TEOE was evaluated for alterations in cell viability and barrier permeability. ALI/keratinocyte growth factor-supplemented (ALI-KGS) culture conditions led to the formation of an 8-20-layer thick, intercellularly connected epithelial barrier. TEER values of ALI-KGS-developed TEOE decreased compared with all other tested conditions, and the established epithelium intensively expressed pCK. Exposure to dental monomers affected the integrity and architecture of TEOE and induced cellular vacuolation, implicating hydropic degeneration. Despite structural modifications, the permeability of TEOE was not substantially affected after exposure to the monomers. In conclusion, the biological properties of the TEOE mimicking the physiological functional conditions and its value as biocompatibility assessment tool for dental materials were characterized.

Comparative analysis of the bioaccumulation of bisphenol A in the blood serum and follicular fluid of women living in two areas with different environmental impacts

Introduction

Bisphenol A (BPA) is a common contaminant widely used in many industrial sectors. Because of its wide use and dispersion, it can be accumulated in living human bodies through both oral assumption and nondietary routes. BPA exhibits hormone-like properties, falling under the class of endocrine disruptors; therefore, it can alter relevant physiological functions. In particular, in women, it can affect folliculogenesis and therefore reproduction, contributing not only to infertility, but also to endometriosis and premature puberty.

Methods

We conducted a multicenter study on 91 women undergoing a first in vitro fertilization (IVF) treatment in the Campania region (Southern Italy). We investigated the presence and concentration of BPA in serum and follicular fluids to assess the effects of airborne BPA contamination. The analysis was conducted on 32 women living in a low environmental impact (LEI) area, from the Sele Valley River and Cilento region, and 59 women living in a high environmental impact (HEI) area, the so-called "Land of Fires", a highly contaminated territory widely exposed to illegal waste practices.

Results

A higher average BPA content in both blood serum and follicular fluid was revealed in the HEI group when compared with the LEI group. In addition, we revealed higher average BPA content in blood serum than in folliclular fluid in the HEI area, with opposite average content in the two fluids in the LEI zone. In addition, our results also showed a lack of correlation between BPA content in follicular and serum fluids both in the overall population and in the HEI and LEI groups, with peculiar trends in different subsets of women.

Conclusion

From our results, we revealed a heterogeneity in the distribution of BPA content between serum and follicular fluid. Further studies are needed to unravel the bioaccumulation mechanisms of BPA in highly polluted and nonpolluted areas.

Polyphenols Regulate the Activity of Endocrine-Disrupting Chemicals, Having Both Positive and Negative Effects

Endocrine-disrupting chemicals (EDCs) are chemical substances that can interfere with any hormone action. They are categorized according to origin and use, such as industrial chemicals like polychlorinated biphenyls (PCBs) and polybrominated biphenyls (PBBs), plastics like bisphenol A (BPA), plasticizers like phthalates, pesticides like dichlorodiphenyltrichloroethane (DDT), fungicides like vinclozolin, and pharmaceuticals like diethylstilbestrol (DES). Natural EDCs, such as phytoestrogens, are present in the diet of both humans and animals. Polyphenols are a large group of natural compounds derived from plants and are found in beverages and food. They are grouped based on their chemical structure into flavonoids and nonflavonoids and are reported to have many beneficial effects on health, including, but not limited to, anticancer, antioxidant, and anti-inflammatory effects. Moreover, polyphenols have both pro- and antioxidant characteristics, and due to their antioxidant and anti-inflammatory potential, they presumably have a protective effect against damage induced by EDCs. However, polyphenols may act as EDCs. In this review, we report that polyphenols regulate the activity of EDCs, having both positive and negative effects. Hence, a better understanding of the associations between EDCs and polyphenols will allow the establishment of improved approaches to protect human health from EDCs.

Sub-acute bisphenol A exposure induces proteomic alterations and impairs male reproductive health in mice

Bisphenol A (BPA) is one of the most prevalent endocrine disrupting chemicals (EDCs) and there is widespread concern about the adverse effects of EDCs on human health. However, the exact mechanism of these toxicities has still not been fully deciphered. Additionally, studies have reported the toxicological effects at far low doses to the generally considered no-observed-adverse-effect level (NOAEL) dose. The present study investigates the effects of a sub-acute (28 days) exposure to BPA (10, 50 and 100 mg/kg/day) in adult male mice on various hormones levels, sperm motility, sperm count, functional integrity of sperm plasma membrane, testicular histological changes, oxidative stress markers and DNA damage. The key proteome signatures were quantified by LC-MS/MS analysis using Orbitrap Fusion Lumos Tribrid Mass Spectrometer equipped with nano-LC Easy-nLC 1200. Data suggest that the BPA exposure in all doses (below/above NOAEL dose) have greatly impacted the hormone levels, sperm parameters (sperm count, motility and membrane integrity) and testicular histology. Mass spectrometry-based proteomics data suggested for 1352 differentially expressed proteins (DEPs; 368 upregulated, 984 downregulated) affecting biological process, cellular component, and molecular functions. Specifically searched male reproductive function related proteins suggested a complex network where 46 potential proteins regulating spermatogenesis, sperm structure, activity and membrane integrity while tackling oxidative stress responses were downregulated. These potential biomarkers could shed some more light on our current understanding of the reproductive toxicological effects of BPA and may lead to exploration of novel interventions strategies against these targets for male infertility.

Unraveling the role of bisphenol A in osteosarcoma biology: insights into prognosis and immune microenvironment modulation

BACKGROUND

Bisphenol A (BPA) is a common environmental pollutant, and its specific mechanisms in cancer development and its impact on the tumor immune microenvironment are not yet fully understood.

METHODS

Transcriptome data from osteosarcoma (OS) patients were downloaded from the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) database. BPA-related genes were identified through the Comparative Toxicogenomics Database (CTD), yielding 177 genes. Differentially expressed genes were analyzed using the GSE162454 dataset from the Tumor Immune Single Cell Hub 2 (TISCH2). We constructed the prognostic model using univariate Cox regression and LASSO analysis. The model was validated using the GSE16091 dataset. GO, KEGG, and GSEA analyses were performed to investigate the mechanisms of BPA-related genes.

RESULTS

A total of 15 BPA-related genes were identified as differentially expressed in OS. Univariate Cox regression and LASSO analysis identified four key prognostic genes (FOLR1, MYC, ESRRA, VEGFA). The prognostic model exhibited strong predictive performance with area under the curve (AUC) values of 0.89, 0.6, and 0.79 for predicting 1-, 2-, and 3-year survival, respectively. External validation using the GSE16091 dataset confirmed the model's high accuracy with AUC values exceeding 0.88. Our results indicated that the prognosis of the high-risk population is generally poorer, which may be associated with alterations in the tumor immune microenvironment. In the high-risk group, immune cells showed predominantly low expression levels, while immune checkpoint genes were significantly overexpressed, along with markedly elevated tumor purity. These findings revealed a correlation between upregulation of BPA-related genes and formation of an immunosuppressive microenvironment, leading to unfavorable patient outcomes.

CONCLUSION

Our study highlighted the significant association of BPA with OS biology, particularly in its potential role in modulating the tumor immune microenvironment. We offered a fresh insight into the influence of BPA on cancer development, thus providing valuable insights for future clinical interventions and treatment strategies.

Endocrine disrupting chemicals and obesity prevention: scoping review

INTRODUCTION

Exposure to endocrine disrupting chemicals (EDCs) can result in alterations of natural hormones in the body. The aim of this review article is to highlight the knowledge about EDCs and obesity.

METHODS

A scoping review of the electronic literature was performed using PubMed platform for studies on EDCs and obesity published between the years 2013-2023. A total of 10 systematic reviews and meta-analysis studies met our inclusion criteria on more prominent EDCs focusing mainly on bisphenols, including parabens, triclosan, and phthalates, and their association with obesity.

DESIGN

Scoping review.

RESULTS

EDCs, mostly bisphenols and phthalates, are related to health effects, while there is less information on the impact of parabens and triclosan. A series of negative physiological effects involving obesogenic, diabetogenic, carcinogenic, and inflammatory mechanisms as well as epigenetic and microbiota modulations was related to a prolonged EDCs exposure. A more profound research of particular pollutants is required to illuminate the accelerating effects of particular EDCs, mixtures or their metabolites on the mechanism of the development of obesity.

CONCLUSION

Considering the characteristics of EDCs and the heterogeneity of studies, it is necessary to design specific studies of effect tracking and, in particular, education about daily preventive exposure to EDCs for the preservation of long-term public health.

Adolescent exposure to bisphenol-a antagonizes androgen regulation of social behavior in male mice

Social behavior is sexually dimorphic, which is regulated by gonadal hormones in the brain. Our recent study found that exposure to low doses of bisphenol-A (BPA) during adolescence, permanently alters social behavior in adult male mice, but the underlying mechanisms remain unclear. Using adolescent gonadectomy (GDX) male mice with testosterone propionate (TP, 0.5 mg/kg) supplement (TP-GDX), this study showed that BPA antagonized promoting effects of TP on social interaction, sexual behavior, and aggression in GDX mice. BPA eliminated the reversal effects of TP on GDX-induced decrease in the number of immunoreactive to arginine vasopressin (AVP-ir) neurons in the medial amygdala (MeA) and the levels of AVP receptor 1a (V1aR) in the MeA and the nucleus accumbens (NAc). In addition, BPA removed down-regulation in the levels of dopamine (DA) transporter (DAT) and DA receptor 1 (DR1) in the NAc of TP-GDX mice. BPA exposure reduced testosterone (T) levels in the brain and serum and the expression of androgen receptor (AR) protein in the amygdala and striatum of sham-operated and TP-GDX males. These results suggest that adolescent exposure to BPA inhibits regulation of androgen in AVP and DA systems of the brain regions associated with social behavior, and thus alters social behaviors of adult male mice.

Effects of bisphenol A on reproduction, oxidative stress, and lipid regulation in the marine rotifer Brachionus plicatilis

This study reports the effects of bisphenol A (BPA) on the rotifer Brachionus plicatilis, focusing on growth performance, reproductive output, oxidative stress responses, and lipid metabolism genes. High BPA levels disrupted peak daily offspring production and led to oxidative stress and increased superoxide dismutase and catalase activity. The research identified distinctive monoacylglycerol O-acyltransferase (MGAT) and diacylglycerol O-acyltransferase (DGAT) genes in B. plicatilis, B. rotundiformis, and B. koreanus, enhancing understanding of lipid metabolism in these species. BPA exposure significantly altered MGAT and DGAT expression, and feeding status affected these regulatory patterns. When food was unavailable, BPA reduced DGAT2 and MGAT2a expression. However, under feeding conditions, DGAT2 and MGAT1 levels increased, indicating that nutritional status and BPA exposure interact to affect gene expression.

A second hit by PFOS exposure exacerbated developmental defects in medaka embryos with a history of ancestral BPA exposure

Bisphenol-A (BPA), a known endocrine-disrupting chemical (EDC) in plastics and resins, has been found to induce heritable health effects in fish and mammals, affecting directly exposed individuals and indirectly their progenies in subsequent generations. It is not clearly understood if subsequent generations of the BPA-exposed ancestors have increased sensitivity to the second hit by the chemicals of emerging concern. To understand this, the present study examined the effects of developmental exposure to perfluorooctanesulfonic acid (PFOS), which has been a global contaminant recently, in embryos whose ancestors were exposed to BPA. Two lineages of medaka (Oryzias latipes) were established: 1) the BPA lineage in which the F0 generation was exposed to 10 μg/L BPA during early development and 2) the control lineage with no BPA exposure in the F0 generation. These lineages were raised up to the F4 generation without further exposure. The embryos of the F4 generation were exposed to PFOS at 0, 0.002, 0.02, 0.2, 2, and 20 mg/L concentrations. Early developmental defects resulting in mortality, delayed hatching, teratogenic phenotypes, and altered gene expression were examined in both lineages. The expression level of genes encoding DNA methyltransferases and genes responsible for oxidative stress defense were determined. Following environmentally relevant PFOS exposure, organisms with a history of BPA exposure displayed significant changes in all categories of developmental defects mentioned above, including increased expression of genes related to oxidative stress, compared to individuals without BPA exposure. The present study provides initial evidence that a history of ancestral BPA exposure can alter sensitivity to developmental disorders following the second hit by PFOS exposure. The variable of ancestral BPA exposure could be considered in mechanistic, medical, and regulatory toxicology, and can also be applied to holistic environmental equity research.

Deciphering the mechanisms and interactions of the endocrine disruptor bisphenol A and its analogs with the androgen receptor

Bisphenol A (BPA) and its various forms used as BPA alternatives in industries are recognized toxic compounds and antiandrogenic endocrine disruptors. These chemicals are widespread in the environment and frequently detected in biological samples. Concerns exist about their impact on hormones, disrupting natural biological processes in humans, together with their negative impacts on the environment and biotic life. This study aims to characterize the interaction between BPA analogs and the androgen receptor (AR) and the effect on the receptor's normal activity. To achieve this goal, molecular docking was conducted with BPA and its analogs and dihydrotestosterone (DHT) as a reference ligand. Four BPA analogs exhibited higher affinity (-10.2 to -8.7 kcal/mol) for AR compared to BPA (-8.6 kcal/mol), displaying distinct interaction patterns. Interestingly, DHT (-11.0 kcal/mol) shared a binding pattern with BPA. ADMET analysis of the top 10 compounds, followed by molecular dynamics simulations, revealed toxicity and dynamic behavior. Experimental studies demonstrated that only BPA disrupts DHT-induced AR dimerization, thereby affecting AR's function due to its binding nature. This similarity to DHT was observed during computational analysis. These findings emphasize the importance of targeted strategies to mitigate BPA toxicity, offering crucial insights for interventions in human health and environmental well-being.

Rats' testicular toxicity induced by bisphenol A is lessened by crocin via an antiapoptotic mechanism and bumped P-glycoprotein expression

Bisphenol A (BPA) engenders testicular toxicity via hydroxyl free radical genesis in rat striatum and depletion of the endogenous antioxidants in the epididymal sperms. The multi-drug resistance efflux carrier; P-glycoprotein (P-gp) expel the BPA from the testis and is responsible for the testicular protection through the deactivation of numerous xenobiotics. In our study, we investigated whether the BPA-induced testicular toxicity could be circumvented through administration of an antioxidant; crocin (Cr). Implication of P-gp expression was also investigated. Rats administered BPA (10 mg/kg b.w. orally for 14 days), dropped the body weight, testes/body weight ratio, total protein content, testosterone, follicle stimulating hormone, luteinizing hormone, and sperm motility & count, total antioxidant status, glutathione content and antioxidant enzymes (superoxide dismutase and catalase), concomitant with the elevation of the percentage abnormal sperm morphology, as well as testicular lipid peroxides and nitrite/nitrate levels. Histopathological examination showed spermatogenesis disorders after the BPA rats exposure. The immunohistochemical study showed up-regulation of the P-gp as evident by increasing immunoreactivity in interstitial cells, with positive localization in some spermatogonia cells. The BPA-treated rats showed positive immunoreactivity against caspase-3. The co-intake of Cr (200 mg/kg b.w./day, i.p. 14 days) along with the BPA, significantly ameliorated all the mentioned parameters, boosted histopathological image, fell the caspase-3 up-regulation, and perched the P-gp expression. We showed that, Cr promotes P-gp as an approach to nurture the testicles against the BPA toxicity. In conclusion; Cr lessens the oxidative stress conditions to safeguard rats from the BPA-induced testicular toxicity and sex hormones abnormalities, reducing apoptosis and up-regulating P-gp.

In vitro assessment of potential endocrine disrupting activities of chlorinated paraffins of various chain lengths

The production of chlorinated paraffins (CPs) has risen in the past two decades due to their versatile industrial applications. Consequently, CPs are now widely detected in human food sources, the environment, and in human matrices such as serum, the placenta and breast milk. This raises concern about prenatal and postnatal exposure. While some studies suggest that certain short-chained CPs (SCCPs) may have endocrine disrupting properties, knowledge about potential endocrine disrupting potential of medium- (MCCP) and long-chained CPs (LCCPs) remains relativity sparse. Here, we used a panel of in vitro assays to investigate seven pure CPs and two technical mixtures of CPs. These varied in chain length and, chlorination degree. The in vitro panel covered androgen, estrogen, and retinoic acid receptor activities, transthyretin displacement, and steroidogenesis. One of the SCCPs inhibited androgen receptor (AR) activity. All SCCPs induced estrogen receptor (ER) activity. Some SCCPs and MCCPs increased 17β-estradiol levels in the steroidogenesis assay, though not consistently across all substances in these groups. SCCPs exhibited the most pronounced effects in multiple in vitro assays, while the tested LCCPs showed no effects. Based on our results, some CPs can have endocrine disrupting potential in vitro. These findings warrant further examinations to ensure that CPs do not cause issues in intact organisms, including humans.

Food, nutrition, and fertility: from soil to fork

Food and nutrition-related factors, including foods and nutrients consumed, dietary patterns, use of dietary supplements, adiposity, and exposure to food-related environmental contaminants, have the potential to impact semen quality and male and female fertility; obstetric, fetal, and birth outcomes; and the health of future generations, but gaps in evidence remain. On 9 November 2022, Tufts University's Friedman School of Nutrition Science and Policy and the school's Food and Nutrition Innovation Institute hosted a 1-d meeting to explore the evidence and evidence gaps regarding the relationships between food, nutrition, and fertility. Topics addressed included male fertility, female fertility and gestation, and intergenerational effects. This meeting report summarizes the presentations and deliberations from the meeting. Regarding male fertility, a positive association exists with a healthy dietary pattern, with high-quality evidence for semen quality and lower quality evidence for clinical outcomes. Folic acid and zinc supplementation have been found to not impact male fertility. In females, body weight status and other nutrition-related factors are linked to nearly half of all ovulation disorders, a leading cause of female infertility. Females with obesity have worse fertility treatment, pregnancy-related, and birth outcomes. Environmental contaminants found in food, water, or its packaging, including lead, perfluorinated alkyl substances, phthalates, and phenols, adversely impact female reproductive outcomes. Epigenetic research has found that maternal and paternal dietary-related factors can impact outcomes for future generations. Priority evidence gaps identified by meeting participants relate to the effects of nutrition and dietary patterns on fertility, gaps in communication regarding fertility optimization through changes in nutritional and environmental exposures, and interventions impacting germ cell mechanisms through dietary effects. Participants developed research proposals to address the priority evidence gaps. The workshop findings serve as a foundation for future prioritization of scientific research to address evidence gaps related to food, nutrition, and fertility.

Hormone effects of eighteen bisphenol analogues and their effects on cellular homeostasis and the typical signal pathways

Through the transfer chain of surroundings from feed to the farmed-animals and ultimately the corresponding livestock and poultry products, people are exposed to large amounts of bisphenol analogues (BPs), such as rational emissions from manufacturing plants, feed packaging bags and food packaging contact. Some BPs have been reported to show certain toxicological effects, especially, estrogen and endocrine disrupting effect. With the increasing application of BPs, the problem is becoming more and more serious. We systematically studied the hormonal effects of 18 BPs and their effects on cell homeostasis and classical signaling pathways by using classical E-SCREEN assay, fluorescent probes and western blotting. The results confirmed the estrogen-like effect of 13 BPs and 6 BPs obtained high docking scores (Scores < -9.0) for the three receptors simultaneously with the main interactions of hydrophobic, hydrogen and π-stacking of T-type bonds. BPAP regulates cells via apoptosis and steroid signaling pathway by intracellular ROS and mitochondrial followed the caspase pathway. BPE and BPS were involved in the classical NF-κB and Hippo signaling pathways. All data provides scientific basis for the safety risk assessment of endocrine disrupting and cellular homeostasis evaluation of BPs as chronic environmental pollution.

Endocrine-disrupting chemicals and male reproductive health

Modifiable factors, such as environmental exposures, can impact human fertility. The objective of this review is to summarize the potential effects of exposure to important endocrine-disrupting chemicals on male reproductive health. Most experimental and animal data demonstrate strong evidence for the negative effects of exposure to phenols, phthalates, pesticides, and perfluoroalkyl and polyfluoroalkyl substances on male reproductive health. Although evidence of negative associations in humans was overall strong for phthalates and pesticides, limited and inconclusive relationships were found for the other examined chemical biomarkers. Reasons for the discrepancies in results include but are not limited to, differences in study populations, exposure concentrations, number of samples collected, sample sizes, study design, and residual confounding. Additional studies are needed, particularly for newer phenols and perfluoroalkyl and polyfluoroalkyl substances, given the scarce literature on the topic and increasing exposures over time.

Bisphenol A induced neuronal apoptosis and enhanced autophagy in vitro through Nrf2/HO-1 and Akt/mTOR pathways

Bisphenol A (BPA) was traditionally used in epoxy resins and polycarbonate plastics, but it was found to be harmful to human health due to its endocrine-disrupting effects. It can affect various biological functions of human beings and interfere with brain development. However, the neurotoxic mechanisms of BPA on brain development and associated neurodegeneration remain poorly understood. Here, we reported that BPA (100, 250, 500 μM) inhibited cell viability of neural cells PC12, SH-SY5Y and caused dose-dependent cell death. In addition, BPA exposure increased intracellular reactive oxygen species (ROS) and mitochondrial ROS (mtROS) levels, decreased mitochondrial membrane potential, reduced the expression of cytochrome c oxidase IV (COX4), downregulated Bcl-2, and initiated apoptosis. Moreover, BPA treatment resulted in the accumulation of intracellular acidic vacuoles and increased the autophagy marker LC3 II to LC3 I ratio. Furthermore, BPA exposure inhibited Nrf2/ HO-1 and AKT/mTOR pathways and mediated cellular oxidative stress, apoptosis, and excessive autophagy, leading to neuronal degeneration. The interactions between oxidative stress, autophagy, and apoptosis during BPA-induced neurotoxicity remain unclear and require further in vivo confirmation.

Low-dose bisphenols exposure sex-specifically induces neurodevelopmental toxicity in juvenile rats and the antagonism of EGCG

Bisphenols (BPs) can negatively affect neurobehaviors in rats, whereas the mechanism remains unclear. Here, the mechanism of BPs-induced neurodevelopmental toxicity and its effective detoxification measures were investigated in vitro and in vivo. In in vitro experiments, primary hippocampal neurons from neonatal rats of different genders were treated with bisphenol A (BPA), bisphenol S (BPS) and bisphenol B (BPB) at 1 nM-100 μM, epigallocatechin gallate (EGCG) and G15, an antagonist of G protein-coupled estrogen receptor (GPER) for 7 d. Results indicated that BPs affected neuronal morphogenesis, impaired GABA synthesis and Glu/GABA homeostasis. Neuronal morphogenetic damage induced by low-doses BPA may be mediated by GPER. Neurotoxicity of BPS is weaker than BPA and BPB. In in vivo studies, exposure to BPA (0.5 μg/kg·bw/day) on PND 10-40 caused oxidative stress and inflammation in rat hippocampus, disrupted neuronal morphogenesis and neurotransmitter homeostasis, ultimately impaired spatial memory of rats. Males are more sensitive to BPA exposure than females. Both in vivo and in vitro studies indicated that EGCG, a phytoestrogen, can alleviate BPA-induced neurotoxicity. Taken together, low-doses BPA exposure sex-specifically disrupted neurodevelopment and further impaired learning and memory ability in rats, which may be mediated by GPER. Promisingly, EGCG effectively mitigated the BPA-induced neurodevelopmental toxicity.

Bisphenol-A release from thermoplastic clear aligner materials: A systematic review

AIM

The aim of the present study was to undertake a systematic review of the available evidence on the release of bisphenol-A (BPA) from thermoplastic materials used in the fabrication of clear aligners (CA).

METHODS

Electronic databases, such as MEDLINE (via PubMed), Google Scholar, Scopus, Cochrane Library, Web of Science, OpenGrey, and the U.S. National Institute of Heath-Clinical Trials, were searched up to 27 October 2022. In vivo/in vitro studies that assessed the release of BPA from different thermoplastic CA materials, with or without a control group, were selected. The risk of bias (RoB) in the randomised controlled trials (RCT) and in vitro studies was assessed using the Cochrane RoB tool and the guidelines for the reporting of pre-clinical studies, respectively. The quality of evidence was determined using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) Pro tool.

RESULTS

Six studies were considered for review from a total of 1926 records. This included one RCT and five in vitro studies. Only two studies found leaching of BPA, while four did not report any traces. The RoB was found to be moderate to high. The GRADE evidence level ranged from low to very low. Five of the included studies were conducted in vitro. Significant heterogeneity among the included studies prevented a quantitative synthesis.

CONCLUSION

In light of the available conflicting evidence, BPA release from CAs can neither be confirmed nor denied. Safety remains questionable until high-quality in vivo trials prove otherwise.

REGISTRATION

PROSPERO CRD42022310434.

Bisphenols as promoters of the dysregulation of cellular junction proteins of the blood-testis barrier in experimental animals: A systematic review of the literature

Daily, people are exposed to chemicals and environmental compounds such as bisphenols (BPs). These substances are present in more than 80% of human fluids. Human exposure to BPs is associated with male reproductive health disorders. Some of the main targets of BPs are intercellular junction proteins of the blood-testis barrier (BTB) in Sertoli cells because BPs alter the expression or induce aberrant localization of these proteins. In this systematic review, we explore the effects of BP exposure on the expression of BTB junction proteins and the characteristics of in vivo studies to identify potential gaps and priorities for future research. To this end, we conducted a systematic review of articles. Thirteen studies met our inclusion criteria. In most studies, animals treated with bisphenol-A (BPA) showed decreased occludin expression at all tested doses. However, bisphenol-AF treatment did not alter occludin expression. Cx43, ZO-1, β-catenin, nectin-3, cortactin, paladin, and claudin-11 expression also decreased in some tested doses of BP, while N-cadherin and FAK expression increased. BP treatment did not alter the expression of α and γ catenin, E-cadherin, JAM-A, and Arp 3. However, the expression of all these proteins was altered when BPA was administered to neonatal rodents in microgram doses. The results show significant heterogeneity between studies. Thus, it is necessary to perform more research to characterize the changes in BTB protein expression induced by BPs in animals to highlight future research directions that can inform the evaluation of risk of toxicity in humans.

Genetic background in the rat affects endocrine and metabolic outcomes of bisphenol F exposure

Environmental bisphenol compounds like bisphenol F (BPF) are endocrine-disrupting chemicals (EDCs) affecting adipose and classical endocrine systems. Genetic factors that influence EDC exposure outcomes are poorly understood and are unaccounted variables that may contribute to the large range of reported outcomes in the human population. We previously demonstrated that BPF exposure increased body growth and adiposity in male N/NIH heterogeneous stock (HS) rats, a genetically heterogeneous outbred population. We hypothesize that the founder strains of the HS rat exhibit EDC effects that were strain- and sex-dependent. Weanling littermate pairs of male and female ACI, BN, BUF, F344, M520, and WKY rats randomly received either vehicle (0.1% EtOH) or 1.125 mg BPF/l in 0.1% EtOH for 10 weeks in drinking water. Body weight and fluid intake were measured weekly, metabolic parameters were assessed, and blood and tissues were collected. BPF increased thyroid weight in ACI males, thymus and kidney weight in BUF females, adrenal weight in WKY males, and possibly increased pituitary weight in BN males. BUF females also developed a disruption in activity and metabolic rate with BPF exposure. These sex- and strain-specific exposure outcomes illustrate that HS rat founders possess diverse bisphenol-exposure risk alleles and suggest that BPF exposure may intensify inherent organ system dysfunction existing in the HS rat founders. We propose that the HS rat will be an invaluable model for dissecting gene EDC interactions on health.

Oxidative damage contributes to bisphenol S-induced development block at 2-cell stage preimplantation embryos in mice through inhibiting of embryonic genome activation

Although bisphenol S (BPS), as a bisphenol A (BPA) substitute, has been widely used in the commodity, it is embryotoxic in recent experiments. Nowadays, it remains unclear how BPS affects preimplantation embryos. Here, my team investigated the effects of BPS on preimplantation embryos and the possible molecular mechanisms in mice. The results showed that 10^-6 mol/L BPS exposure delayed the blastocysts stage, and exposure to 10^-4 mol/L BPS induced 2-cell block in mice preimplantation embryos. A significant increase in reactive oxygen species (ROS) level and antioxidant enzyme genes Sod1, Gpx1, Gpx6, and Prdx2 expression were shown, but the level of apoptosis was normal in 2-cell blocked embryos. Further experiments demonstrated that embryonic genome activation (EGA) specific genes Hsp70.1 and Hsc70 were significantly decreased, which implied that ROS and EGA activation have the potential to block 2-cell development. Antioxidant enzymes, including superoxide dismutase (SOD), coenzyme Q10 (CoQ10), and folic acid (FA) were used to further explore the roles of ROS and EGA in 2-cell block. Only 1200 U/mL SOD was found to alleviate the phenomenon of 2-cell block, reduce oxidative damage, and restore the expression of EGA-specific genes Hsp70.1 and Hsc70. Conclusively, this study demonstrates for the first time that BPS can induce 2-cell block, which is mainly mediated by ROS aggregation and results in the failure of EGA activation.

Bisphenol S Reduces Pig Spermatozoa Motility through Different Intracellular Pathways and Mechanisms than Its Analog Bisphenol A

Bisphenol A (BPA: 2,3-bis (4-hydroxyphenyl) propane) is an environmental chemical widely used in the manufacturing of epoxy polymers and many thermoplastic consumer products. Serious concerns about its safety led to the development of analogs, such as BPS (4-hydroxyphenyl sulfone). Very limited studies about BPS's impact on reproduction, specifically in spermatozoa, exist in comparison with BPA. Therefore, this work aims to study the in vitro impact of BPS in pig spermatozoa in comparison with BPA, focusing on sperm motility, intracellular signaling pathways and functional sperm parameters. We have used porcine spermatozoa as an optimal and validated in vitro cell model to investigate sperm toxicity. Pig spermatozoa were exposed to 1 and 100 μM BPS or BPA for 3 and 20 h. Both bisphenol S and A (100 μM) significantly reduce pig sperm motility in a time-dependent manner, although BPS exerts a lower and slower effect than BPA. Moreover, BPS (100 μM, 20 h) causes a significant increase in the mitochondrial reactive species, whereas it does not affect sperm viability, mitochondrial membrane potential, cell reactive oxygen species, GSK3α/β phosphorylation or phosphorylation of PKA substrates. However, BPA (100 μM, 20 h) leads to a decrease in sperm viability, mitochondrial membrane potential, GSK3β phosphorylation and PKA phosphorylation, also causing an increase in cell reactive oxygen species and mitochondrial reactive species. These intracellular effects and signaling pathways inhibited might contribute to explaining the BPA-triggered reduction in pig sperm motility. However, the intracellular pathways and mechanisms triggered by BPS are different, and the BPS-caused reduction in motility can be only partially attributed to an increase in mitochondrial oxidant species.

In utero bisphenol A exposure disturbs germ cell cyst breakdown through the PI3k/Akt signaling pathway and BDNF expression

PURPOSE

To determine the influence of the environmental endocrine disruptor bisphenol A (BPA) on germ cell cyst breakdown and explore the possible mechanisms regulating this activity.

METHODS

BPA (2 μg/kg/d or 20 μg/kg/d) or tocopherol-stripped corn oil (vehicle control) was administered to pregnant mice by gavage at gestational day 11, and the offspring (prenatally treated mice) were sacrificed and ovariectomized at postnatal day (PND) 4 and PND22. Ovarian morphology was documented in the first filial (F1) generation female offspring, and the follicles were analyzed and classified morphologically on PND 4. To discover differentially expressed genes and associated target pathways, we used RNA-seq, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and Gene Ontology (GO) analysis. The mRNA expression of key steroid hormone synthesis-related genes was evaluated by Q-PCR in forskolin-induced KGN cells. Western blotting (WB) and qRTPCR were used to determine the protein and gene expression levels of brain-derived neurotrophic factor (BDNF).

RESULTS

BPA, a typical endocrine disrupting chemical (EDC), decreased the expression of the key steroid hormone synthesis-related genes P450scc and aromatase, while the expression of Star increased significantly and caused no significant difference in the expression of Cyp17a1 or HSD3β in forskolin-induced KGN cells. Moreover, we confirmed that in utero exposure to environmentally relevant concentrations of BPA (2 μg/kg/d and 20 μg/kg/d) could significantly disrupt germ cell cyst breakdown, leading to the generation of fewer primordial follicles than in the control group. The factors mediating the inhibitory effects included the PI3K-Akt signaling pathway and a significant downregulation of BDNF.

CONCLUSIONS

These findings indicate that in utero exposure to BPA at low doses, which are lower than recommended as 'safe' dosages, may influence the formation of primordial follicles by inhibiting the expression of steroid hormone synthesis-related genes and partly by regulating the BDNF-mediated PI3K/Akt pathway.

Exposure, toxicological mechanism of endocrine disrupting compounds and future direction of identification using nano-architectonics

Endocrine-disrupting compounds (EDC) are a group of exogenous chemicals that structurally mimic hormones and interfere with the hormonal signaling cascade. EDC interacts with hormone receptors, transcriptional activators, and co-activators, altering the signaling pathway at both genomic and non-genomic levels. Consequently, these compounds are responsible for adverse health ailments such as cancer, reproductive issues, obesity, and cardiovascular and neurological disorders. The persistent nature and increasing incidence of environmental contamination from anthropogenic and industrial effluents have become a global concern, resulting in a movement in both developed and developing countries to identify and estimate the degree of exposure to EDC. The U.S. Environment Protection Agency (EPA) has outlined a series of in vitro and in vivo assays to screen potential endocrine disruptors. However, the multidisciplinary nature and concerns over the widespread application demand alternative and practical techniques for identifying and estimating EDC. The review chronicles the state-of-art 20 years (1990-2023) of scientific literature regarding EDC's exposure and molecular mechanism, highlighting the toxicological effects on the biological system. Alteration in signaling mechanisms by representative endocrine disruptors such as bisphenol A (BPA), diethylstilbestrol (DES), and genistein has been emphasized. We further discuss the currently available assays and techniques for in vitro detection and propose the prominence of designing nano-architectonic-sensor substrates for on-site detection of EDC in the contaminated aqueous environment.

Exposure to bisphenol A induces neurotoxicity associated with synaptic and cytoskeletal dysfunction in neuro-2a cells

Bisphenol A (BPA) has been reported to injure the developing and adult brain. However, the underlying mechanism still remains elusive. This study used neuro-2a cells as a cellular model to investigate the neurotoxic effects of BPA. Microtubule-associated protein 2 (MAP2) and tau protein maintain microtubule normal function and promote the normal development of the nervous system. Synaptophysin (SYP) and drebrin (Dbn) proteins are involved in regulating synaptic plasticity. Cells were exposed to the minimum essential medium (MEM), 0.01% (v/v) DMSO, and 150 μM BPA for 12, 24, or 36 h. Morphological analysis revealed that the cells in the BPA-treated groups shrank and collapsed compared with those in the control groups. CCK-8 and lactate dehydrogenase assay (LDH) assays showed that the mortality of neuro-2a cells increased as the BPA treatment time was prolonged. Ultrastructural analysis further revealed that cells demonstrated nucleolar swelling, dissolution of nuclear and mitochondrial membranes, and partial mitochondrial condensation following exposure to BPA. BPA also decreased the relative protein expression levels of MAP2, tau, and Dbn. Interestingly, the relative protein expression levels of SYP increased. These results indicated that BPA inhibited the proliferation and disrupted cytoskeleton and synaptic integrity of neuro-2a cells.

Molecular insights underlying the adverse effects of bisphenol A on gonadal somatic cells' steroidogenic activity

Bisphenol A (BPA) exposure may impair gonadal steroidogenesis, although the underlying mechanism is not well known. Hereby, we assessed BPA action on human primary granulosa (hGC) and mouse Leydig cells (BLTK-1) proliferation, cytotoxicity, hormone secretion, and steroidogenic enzyme/receptor gene profile. hGC and BLTK-1 cells were stimulated with increasing concentrations of BPA (10^-12 M to 10^-4 M for cell proliferation assay, 10^-8 M to 10^-4 M for LDH-cytotoxicity assay, and 10^-9 M to 10^-5 M for hormone secretion and genes expression analysis). BPA at low concentrations (pM - nM) did not affect cell proliferation in either cell type, although was toxic at higher (µM) concentrations. BPA stimulation at low nM concentrations decreased the production of estradiol (E₂) and testosterone (T) in BLTK-1, E_2, and progesterone in hGCs. BPA down-regulated Star, Cyp11a1, and Hsd17b3, but up-regulated Cyp19a1, Esr1, Esr2, and Gpr30 expression in BLTK-1 cells. In hGC, BPA down-regulated STAR, CYP19A1, PGRMC1, and PAQR7 but up-regulated ESR2 expression. Estrogen receptor degrader fulvestrant (FULV) attenuated BPA inhibition of hormone production in both cell lines. FULV also blocked the BPA-induced Gpr30 up-regulation in BLTK-1 cells, whereas in hGC, failed to reverse the down-regulation of PGRMC1, STAR, and CYP19A1. Our findings provide novel mechanistic insights into environmentally-relevant doses of BPA action through both nuclear estrogen receptor-dependent and independent mechanisms affecting cultured granulosa and Leydig cell steroidogenesis.

Susceptibility of male reproductive system to bisphenol A, an endocrine disruptor: Updates from epidemiological and experimental evidence

Bisphenol A (BPA) is an omnipresent environmental pollutant. Despite being restrictions in-force for its utilization, it is widely being used in the production of polycarbonate plastics and epoxy resins. Direct, low-dose, and long-term exposure to BPA is expected when they are used in the packaging of food products and are used as containers for food consumption. Occupationally, workers are typically exposed to BPA at higher levels and for longer periods during the manufacturing process. BPA is a known endocrine disruptor chemical (EDC), that causes male infertility, which has a negative impact on human life from emotional, physical, and societal standpoints. To minimize the use of BPA in numerous consumer products, efforts and regulations are being made. Despite legislative limits in numerous nations, BPA is still found in consumer products. This paper examines BPA's overall male reproductive toxicity, including its impact on the hypothalamic-pituitary-testicular (HPT) axis, hormonal homeostasis, testicular steroidogenesis, sperm parameters, reproductive organs, and antioxidant defense system. Furthermore, this paper highlighted the role of non-monotonic dose-response (NMDR) in BPA exposure, which will help to improve the overall understanding of the harmful effects of BPA on the male reproductive system.

A systematic review of biocompatibility and safety of orthodontic clear aligners and transparent vacuum-formed thermoplastic retainers: Bisphenol-A release, adverse effects, cytotoxicity, and estrogenic effects

Background

An ever-increasing demand is seen for clear aligners and transparent vacuum-formed retainers. They are esthetic and convenient. However, the biomaterials used in these appliances might pose biological safety and biocompatibility threats in terms of their bisphenol-A (BPA) release, cytotoxicity, adverse effects, and estrogenic effects. Due to the controversial results and the lack of any systematic reviews in this regard, we conducted this systematic review.

Materials and Methods

Web of Science, PubMed, Cochrane, Scopus, and Google Scholar as well as references of the found articles were searched (independently by 3 researchers) up to December 22, 2021, to find studies relevant to the biocompatibility of clear aligners and thermoplastic retainers. The search keywords were a combination of the following (and more): Essix, vacuum-formed aligner, thermoplastic aligner, clear aligner, Invisalign, vacuum-formed retainer, BPA release, monomer release, cytotoxicity, estrogenicity, biocompatibility, chemical properties, and oral epithelial cell. As eligibility criteria, articles in all languages would be included as long as their text could be translated clearly using online translators or by professional translators; all types of publications (article, book, and thesis) would be included if containing relevant studies and information; they should have been on clear liners or thermoplastic retainers; and they should have been on biocompatibility, safety, cytotoxicity, or estrogenicity of clear aligners or thermoplastic retainers. There were no restrictions on the type of study (randomized clinical trials, experimental in vitro studies). Studies focusing merely on the mechanical properties of clear aligners or thermoplastic retainers (without examining their chemical properties) would be excluded. The risk of bias was assessed.

Results

The risk of bias was rather low. However, the methodologies of the studies were quite different. Overall, 16 articles (1 randomized clinical trial and 15 in vitro studies) were identified. The data for BPA release were reported in four articles (1 clinical trial and 3 in vitro studies). Quantitatively speaking, the amount of released BPA reported by in vitro studies was very low, if not zero. However, the BPA level was very high in the only randomized clinical trial. Many adverse effects were linked to using clear aligners or transparent retainers, including pain and soft-tissue issues such as burning, tingling, sore tongue, lip swelling, blisters, ulceration, dry mouth, periodontal problems, and even systemic problems such as difficulty in breathing. Besides these biological adverse effects, oral dysfunctions and speech difficulties and tooth damage may be associated with clear aligners and should as well be taken into consideration.

Conclusion

Given the very high levels of BPA leach observed in the only clinical trial and considering other possible dangers of small traces of BPA (even at low doses) and also given the numerous adverse events linked to clear aligners or transparent retainers, it seems that safety of these appliances might be questionable and more clinical studies of biocompatibility are needed in this regard.

Sperm parameters in the Great Dane: Influence of age on semen quality

Not all sires have sperm suitable for chilled or frozen storage, and success in artificial insemination (AI) varies highly among individual dogs and breeds. Fertilizing potential is further complicated as sperm quality declines with the aging process. Due to the rapidity of aging and senescence in large breed dogs, associated health and fertility changes may be observed over a shorter period, though this period remains undefined for any breed. Working with a population of purebred Great Danes (GD), our aims were (1) to characterize the distribution of a series of sperm parameters, (2) to distinguish sources of variation in sperm quality within this rapidly aging breed, and (3) to identify changes in sperm quality that may accompany aging. Ejaculates collected from young, middle-aged, and senior Great Dane dogs (n = 50) were evaluated for semen volume, total sperm number and viability, and reactive oxygen species (ROS), in addition to sperm morphology and kinematic parameters. Total testicular volume was also determined using ultrasonography. Testicular volume was not a predictor of sperm production in the GD, however, significant differences between coat colors were identified. Age was negatively associated with total motility, progressive motility, and amplitude of lateral head displacement (ALH) (p < .05). We identified significant relationships between GD male age and TM, PM, and immotility with -9.9%, -9.0%, and +8.3% change per year of age, respectively, which support the anecdotal reports of decline of the fertility with the advance of age in this breed. Sperm of younger GD dogs aged 12 ≤ x < 24 months had significantly higher TM, PM, ALH, and nonlinear motility (p < .05) than older dogs (x ≥ 48 months). High ROS levels were positively associated with TM and PM, average pathway distance (DAP) and straight line distance (DSL), average pathway velocity (VAP), straight line velocity (VSL), and the presence of hairpin tails (p < .05). While age and ROS have significant influences on sperm parameters in the GD, the influence of selection for breed specific phenotypes could help explain the functional significance of the diversity among GD males.

Impacts of bisphenol A on growth and reproductive traits of submerged macrophyte Vallisneria natans

Bisphenol A (BPA) is considered a contaminant of emerging concern and interferes with the normal activities of living organisms. The toxicity of BPA is evident in animals and terrestrial plants. However, the response of aquatic plants to low BPA concentrations is still unclear. In the present study, effects of varying BPA loadings (targeting at 0.01, 0.1, and 1 mg/L) on the growth and reproductive traits of the dioecious annual submerged macrophyte Vallisneria natans were assessed through a 5-month experiment. The results showed that BPA inhibited the elongation of V. natans leaves but resulted in an increase in leaf number and ramet number under the highest BPA loading treatment (targeting at 1 mg/L). In addition, detectable biochemical changes in the total carbon and soluble sugar contents were found, which both were significantly higher at the highest BPA loading treatment. However, the total biomass did not alter significantly after the BPA treatments, indicating that BPA did not induce direct toxic effects on the growth of V. natans. At the highest BPA loading treatment, female individuals of V. natans allocated less number for ramet than male ones, showing a clear sexual dimorphism. No significant differences between the five treatments were found for the flower or fruit traits, while the germination rate was significantly inhibited for the seeds collected from the highest BPA loading treatment. In conclusion, V. natans tolerated low concentrations of BPA by making a trade-off between ramet (leaf) number and leaf elongation, as well as modulating the total carbon and soluble sugar contents. However, serious consequence of decline in seed viability implied that the impact of BPA on plant reproduction were usually underestimated.

Ancestral BPA exposure caused defects in the liver of medaka for four generations

Environmental chemicals can induce liver defects in experimental animals due to their direct and acute exposure. It is not clear whether environmental chemical exposures result in the transgenerational passage of liver defects in subsequent generations living in an uncontaminated environment. Bisphenol A (BPA), a plasticizer chemical, has been ubiquitous in the environment in the recent decade. Every organism is exposed to this chemical at some point during its lifetime. Literature suggests that direct BPA exposure can result in several metabolic diseases, including non-alcoholic fatty liver disease (NAFLD). Despite the phasing out of BPA from several consumer goods, it is unclear whether ancestral BPA exposure causes liver health problems in the unexposed future generations. Here, we demonstrate an advanced stage of NAFLD in the grandchildren (F2 generation) of medaka fish (Oryzias latipes) due to embryonic BPA exposure in the grandparental generation (F0), which persists for five generations (F4) even in the absence of BPA. The severity of transgenerational NAFLD phenotype included steatosis together with perisinusoidal fibrosis and apoptosis of hepatocytes. Adult females developed more severe histopathological conditions in the liver than males. Genes encoding enzymes involved in lipolytic pathways were significantly decreased. The present results suggest that ancestral BPA exposure can result in transgenerational metabolic diseases that can persist for five generations and that the NAFLD trait is sexually dimorphic. Given that ancestral BPA exposure can lead to altered metabolic health outcomes in the subsequent unexposed generations, the development of the methods and strategies to mitigate the transgenerational onset of metabolic diseases seem imperative to protect future generations.

Long-term potentiation and depression regulatory microRNAs were highlighted in Bisphenol A induced learning and memory impairment by microRNA sequencing and bioinformatics analysis

The mechanisms of Bisphenol A (BPA) induced learning and memory impairment have still not been fully elucidated. MicroRNAs (miRNAs) are endogenous non-coding small RNA molecules involved in the process of toxicant-induced neurotoxicity. To investigate the role of miRNAs in BPA-induced learning and memory impairment, we analyzed the impacts of BPA on miRNA expression profile by high-throughput sequencing in mice hippocampus. Results showed that mice treated with BPA displayed impairments of spatial learning and memory and changes in the expression of miRNAs in the hippocampus. Seventeen miRNAs were significantly differentially expressed after BPA exposure, of these, 13 and 4 miRNAs were up- and downregulated, respectively. Bioinformatic analysis of Gene Ontology (GO) and pathway suggests that BPA exposure significantly triggered transcriptional changes of miRNAs associated with learning and memory; the top five affected pathways involved in impairment of learning and memory are: 1) Long-term depression (LTD); 2) Thyroid hormone synthesis; 3) GnRH signaling pathway; 4) Long-term potentiation (LTP); 5) Serotonergic synapse. Eight BPA-responsive differentially expressed miRNAs regulating LTP and LTD were further screened to validate the miRNA sequencing data using Real-Time PCR. The deregulation expression levels of proteins of five target genes (CaMKII, MEK1/2, IP3R, AMPAR1 and PLCβ4) were investigated via western blot, for further verifying the results of gene target analysis. Our results showed that LTP and LTD related miRNAs and their targets could contribute to BPA-induced impairment of learning and memory. This study provides valuable information for novel miRNA biomarkers to detect changes in impairment of learning and memory induced by BPA exposure.

The translational genetics of ADHD and related phenotypes in model organisms

Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent neurodevelopmental disorder resulting from the interaction between genetic and environmental risk factors. It is well known that ADHD co-occurs frequently with other psychiatric disorders due, in part, to shared genetics factors. Although many studies have contributed to delineate the genetic landscape of psychiatric disorders, their specific molecular underpinnings are still not fully understood. The use of animal models can help us to understand the role of specific genes and environmental stimuli-induced epigenetic modifications in the pathogenesis of ADHD and its comorbidities. The aim of this review is to provide an overview on the functional work performed in rodents, zebrafish and fruit fly and highlight the generated insights into the biology of ADHD, with a special focus on genetics and epigenetics. We also describe the behavioral tests that are available to study ADHD-relevant phenotypes and comorbid traits in these models. Furthermore, we have searched for new models to study ADHD and its comorbidities, which can be useful to test potential pharmacological treatments.