Immunomodulatory effects of environmental endocrine disrupting chemicals

Interdependency of estradiol-mediated ERα activation and subsequent PR and GREB1 induction to control cell cycle progression

Various groups of chemicals that we encounter in every-day life are known to disrupt the endocrine system, such as estrogen mimics that can disturb normal cellular development and homeostasis. To understand the effect of estrogen on intracellular protein dynamics and how this relates to cell proliferation, we aimed to develop a quantitative description of transcription factor complexes and their regulation of cell cycle progression in response to estrogenic stimulation. We designed a mathematical model that describes the dynamics of three proteins, GREB1, PR and TFF1, that are transcriptionally activated upon binding of 17β-estradiol (E2) to estrogen receptor alpha (ERα). Calibration of this model to imaging data monitoring the expression dynamics of these proteins in MCF7 cells suggests that transcriptional activation of GREB1 and PR depends on the association of the E2-ERα complex with both GREB1 and PR. We subsequently combined this ER signaling model with a previously published cell cycle model and compared this to quantification of cell cycle durations in MCF7 cells following nuclei tracking based on images segmented with deep neural networks. The resulting model predicts the effect of GREB1 and PR knockdown on cell cycle progression, thus providing mechanistic insight in the molecular interactions between ERα-regulated proteins and their relation to cell cycle progression. Our findings form a valuable basis to further investigate the pharmacodynamics of endocrine disrupting chemicals and their influence on cellular behavior.

Bisphenol A triggers activation of ocular immune system and aggravates allergic airway inflammation

Bisphenol A (BPA) is widely used in manufacturing plastic products, and it has been reported that exposure through the airway or orally aggravates allergic airway inflammation. Because BPA is detected in the atmosphere and indoor environments, the eyes can also be exposed to BPA. After ocular exposure to BPA and antigen via eye drops, we observed enhanced antigen uptake of antigen-presenting cells (APCs) in tear duct-associated lymphoid tissue (TALT). Additionally, we observed the formation of germinal center (GC) B cells in TALT and induction of allergic airway inflammation in mice sensitized with BPA and antigen via eye drops, followed by airway antigen exposure. We also found that DNAX-activating protein of 12 kDa (DAP12)-deficient mice displayed impaired activation of APCs enhanced by ocular exposure to BPA. These results indicate that ocular sensitization to BPA and allergen triggers allergic inflammation via TALT activation, and that DAP12 might be a key molecule for modulating the ocular immune system.

The endocrine disruptor vinclozolin causes endothelial injury via eNOS/Nox4/IRE1α signaling

Vinclozolin (VCZ) is a common dicarboximide fungicide used to protect crops from diseases. It is also an endocrine disruptor, and its effects on various organs have been described but its influence on vasculature has not yet been addressed. This study focuses on the potential mechanism of VCZ-induced vascular injury. The effect of VCZ on vascular function in terms of relaxing and contracting response was evaluated in mice aorta. A short exposure to VCZ affected the endothelial but not the smooth muscle component. Specifically, it caused a disruption of the eNOS/NO signaling. In line, a short exposure to VCZ in bovine aortic endothelial cells promoted eNOS uncoupling resulting in a reduction of NO bioavailability and eNOS dimer/monomer ratio, and in turn an increase of nitro-tyrosine levels and ROS formation. Prolonging the exposure to VCZ (3 and 6h) an up-regulation of Nox4, enzyme-generating ROS constitutively expressed in endothelial cells, and an increase in ROS and malondialdehyde content coupled with a reduction in NO levels were found. These events were strictly linked to endoplasmic reticulum stress as demonstrated by the phosphorylation of inositol-requiring transmembrane kinase endoribonuclease 1α (IRE1α), a stress sensor and its reversion by using a selective inhibitor. Collectively, these results demonstrated that VCZ provokes endothelial dysfunction by oxidative stress involving eNOS/Nox4/IRE1α axis. The rapid exposure affected the endothelial function promoting eNOS uncoupling while a post-transcriptional modification, involving Nox4/IRE1α signaling, occurred following prolonged exposure. Thus, exposure to VCZ could contribute to the onset and/or progression of cardiovascular diseases associated with endothelial dysfunction.

Recent use of consumer and personal care products and exposures to select endocrine disrupting chemicals among urban children with asthma

BACKGROUND

Emerging studies suggest that endocrine disrupting chemicals (EDCs) in personal care and other consumer products are linked with various adverse health effects, including respiratory and reproductive effects. Despite Black persons using more personal care products than other demographic groups and having a high asthma burden, little is known regarding their consumer product use patterns and associated EDC exposures.

OBJECTIVE

To examine the association between recent exposure to select EDCs with specific consumer products and behaviors in a cohort of 110 predominantly Black children with asthma, ages 8-17 years, living in Baltimore City, Maryland.

METHODS

We quantified concentrations of bisphenol A (BPA), bisphenol S (BPS), bisphenol F, two dichlorophenols, four parabens, triclosan, benzophenone-3, and triclocarban in spot urine samples. Questionnaires were used to capture recent (last 24-h) consumer product use and behaviors. Associations between EDCs and consumer product uses/behaviors were assessed using multivariable linear regression, adjusting for age, gender, race/ethnicity, and caregiver income level. Effect estimates were expressed as geometric mean ratios of biomarker concentrations of product-users vs non-users.

RESULTS

Increased concentrations to select EDCs were associated with recent use of air freshener (ratios; BPA: 1.9, 95%CI 1.4-2; BPS 1.7, 95%CI 1-2.97; propyl paraben: 3.0, 95%CI 1.6-5.6), scented candles (methyl paraben: 2.6, 95%CI 1.1-6.1), and scented carpet powder (2,5-dichlorophenol: 2.8, 95%CI 1.2-6.3). Additionally, consuming canned food was associated with some increased biomarker concentrations (ratios: BPA: 1.7, 95%CI 1.2-2.4; BPS: 2.1, 95% CI: 1.2-3.6).

SIGNIFICANCE

These findings add to the body of evidence suggesting that recent use of select consumer products in Black children contributes to exposure of chemicals of concern and could potentially inform exposure mitigation interventions. Findings have broad potential health implications for pediatric populations and Black children who may face exposure and health disparities.

IMPACT

Little is known about how children's personal care product use and consumer behaviors affect their exposures to endocrine disrupting chemicals (EDCs). This is particularly true for Black children who often experience a disparate exposure burden to many EDCs. This is a significant knowledge gap among children that are uniquely vulnerable to EDCs as they undergo critical windows of growth and development. Our findings show associations between consumer products and EDC exposures in predominantly Black children in low-income settings. Identifying EDC exposure determinants has broad health implications as many of these chemicals have been associated with adverse health risks.

A review of cumulative toxic effects of environmental endocrine disruptors on the zebrafish immune system: Characterization methods, toxic effects and mechanisms

Environmental endocrine disrupting chemicals (EDCs), are a type of exogenous organic pollutants, are ubiquitous in natural aquatic environments. Currently, in addition to neurological, endocrine, developmental and reproductive toxicity, ecotoxicology studies on immunotoxicity are receiving increasing attention. In this review, the composition of immune system of zebrafish, the common indicators of immunotoxicity, the immunotoxicity of EDCs and their molecular mechanism were summarized. We reviewed the immunotoxicity of EDCs on zebrafish mainly in terms of immune organs, immunocytes, immune molecules and immune functions, meanwhile, the possible molecular mechanisms driving these effects were elucidated in terms of endocrine disruption, dysregulation of signaling pathways, and oxidative damage. Hopefully, this review will provide a reference for further investigation of the immunotoxicity of EDCs.

Influence of triazines and lipopolysaccharide coexposure on inflammatory response and histopathological changes in the testis and liver of BalB/c mice

Background

Triazines are environmental active chemicals that have been reported to alter the inflammatory status of the gonads. We tested the anti-inflammatory effect of the triazines (atrazine; ATZ, simazine; SMZ and cyanazine; CYZ) on the testis and compared it with the more classical liver model that has substantial populations of resident macrophages comparable to the testis.

Methods

BalB/c mice were treated with 25 mg/kg ATZ, SMZ and CYZ for 30 days and injected with lipopolysaccharide (0.5 mg/kg i.p.) 6 h before sacrifice. Myeloperoxidase activity and nitric oxide level in the testis and liver homogenates were determined by spectrophotometry whereas tumor necrosis factor-alpha and interleukin-6 concentrations were evaluated by immunoassay. Haematoxylin and eosin stained sections of the tissues were observed using a light microscope.

Results

Myeloperoxidase activity, nitric oxide, tumor necrosis factor-alpha, and interleukin-6 levels were decreased in the liver and testis of the triazines co-treated animals. SMZ has the most potent inhibitory effect and ATZ the least effect on inflammatory mediators in both tissues. Microscopic evaluation showed loss of inflammatory cells in the inter-tubular areas of the testis and few patchy masses of infiltrating inflammatory cells around the central vein of the liver.

Conclusion

Triazines inhibit the levels of inflammatory mediators in the testis and liver of mice. The anti-inflammatory effect of triazines in a lipopolysaccharide-induced inflammation model was established in this study.

Impact of endocrine disruptors on peripheral blood mononuclear cells in vitro: role of gender

Humans can be exposed to endocrine disruptors (EDs) in numerous ways. EDs can interfere with endogenous hormones at different levels, resulting in numerous adverse human health outcomes, including immunotoxicity. In this regard, this study aimed to investigate in vitro the possible effects of EDs on immune cells and possible gender differences. Peripheral blood mononuclear cells from healthy humans, both males and females, were exposed to 6 different EDs, namely atrazine (herbicide), cypermethrin (insecticide), diethyl phthalate (plasticizer), 17α-ethynylestradiol (contraceptive drug), perfluorooctanesulfonic acid (persistent organic pollutant), and vinclozolin (fungicide). We evaluated the effect of EDs on RACK1 (receptor for activated C kinase 1) expression, considering it as a bridge between the endocrine and the immune system, and putatively used as screening tool of immunotoxic effects of EDs. The exposure to EDs resulted at different extent in alteration in RACK1 expression, pro-inflammatory activity, natural killer lytic ability, and lymphocyte differentiation, with sex-related differences. In particular, diethyl phthalate and perfluorooctanesulfonic acid resulted the most active EDs tested, with gender differences in terms of effects and magnitude. The results from our study evidenced the ability of EDs to directly affect immune cells.

Features of Spleen Development in Newborn Rats Exposed to Endocrine Disrupter Dichlorodiphenyltrichloroethane during the Prenatal Period

The development of the spleen in newborn male Wistar rats exposed to low-dose endocrine disruptor dichlorodiphenyltrichloroethane during the prenatal period was studied. Histological examination of the spleen revealed a more active development of periarterial lymphoid sheaths and lower granulocyte content in the organ. Cytofluorimetry showed a significantly lower content of B cells. Thus, low-dose exposure of the endocrine disruptor dichlorodiphenyltrichloroethane on the developing organism during the prenatal period induced changes in spleen morphogenesis resulting in extensive development of lymphoid formations and a lower intensity of lymphocyte and granulocyte differentiation.

Environmental endocrine disruptors and pregnane X receptor action: A review

The pregnane X receptor (PXR) is a kind of orphan nuclear receptor activated by a series of ligands. Environmental endocrine disruptors (EEDs) are a wide class of molecules present in the environment that are suspected to have adverse effects on the endocrine system by interfering with the synthesis, transport, degradation, or action of endogenous hormones. Since EEDs may modulate human/rodent PXR, this review aims to summarize EEDs as PXR modulators, including agonists and antagonists. The modular structure of PXR is also described, interestingly, the pharmacology of PXR have been confirmed to vary among different species. Furthermore, PXR play a key role in the regulation of endocrine function. Endocrine disruption of EEDs via PXR and its related pathways are systematically summarized. In brief, this review may provide a way to understand the roles of EEDs in interaction with the nuclear receptors (such as PXR) and the related pathways.

Estrogenic potency of endocrine disrupting chemicals and their mixtures detected in environmental waters and wastewaters

Endocrine disrupting chemicals such as natural and synthetic steroid hormones and bisphenols are among the most important pollutants in the aquatic environment. We performed an environmental chemical analysis of five Slovenian water samples, two rivers, one groundwater, and the influent and effluent of wastewater treatment plants, with a highly sensitive analysis of twenty-five endocrine-disrupting compounds belonging to the groups of natural hormones, synthetic hormones, and bisphenols. Since these compounds are simultaneously present in the environment, it is important to study their individual effects as well as the effects of mixtures. We investigated in vitro the estrogenic potency of selected natural and synthetic steroid hormones and bisphenols detected in surface, ground and waste water in Slovenia using the OECD-validated transactivation assay on the cell line Hela9903. We predicted their mixture effects using the concentration addition model and compared them with experimentally determined values. Two mixing designs were used: a balanced design in which chemicals were combined in proportion to their individual EC₅₀ values, and an unbalanced design with compounds in proportion to their measured concentrations in the environmental samples. The estrogenic effects of the experimental mixtures followed the concentration addition model. Real water samples exhibited weaker estrogenic effects, showing the great heterogeneity of the real water samples.

An integrated in silico-in vitro investigation to assess the skin sensitization potential of 4-Octylphenol

One of the major challenges in chemical toxicity testing is the possibility to protect human health against adverse effects with non-animal methods. In this paper, 4-Octylphenol (OP) was tested for skin sensitization and immunomodulatory effects using an integrated in silico-in vitro test approach. In silico tools (QSAR TOOLBOX 4.5, ToxTree and VEGA) were used together with several in vitro tests including HaCaT cells (quantification of IL-6; IL-8; IL-1α and IL-18 by ELISA and expression of genes TNF, IL1A, IL6 and IL8 by RT- qPCR), RHE model (quantification of IL-6; IL-8; IL-1α and IL-18 by ELISA) and THP-1 activation assay (CD86/CD54 expression and IL-8 release). Additionally, the immunomodulatory effect of OP was investigated using lncRNAs MALAT1 and NEAT1 expression and LPS-induced THP-1 activation (CD86/CD54 expression and IL-8 release). The in silico tools predicted OP as a sensitizer. In vitro tests are also concordant with the in silico prediction. OP increased IL-6 expression (HaCaT cells); IL-18 and IL-8 expressions (RHE model). An irritant potential was also shown by a great expression of IL-1α (RHE model); and increased expression of CD54 marker and IL-8 in THP-1 cells. Immunomodulatory effects of OP were demonstrated by the downregulation of NEAT1, MALAT1 (epigenetic markers), IL6 and IL8; and an increase in LPS-induced CD54 and IL-8 expressions. Overall, results indicate that OP is a skin sensitizer, being positive in three key events of the AOP for skin sensitization, also showing immunomodulatory effects.

Environmental endocrine disruptors and amphibian immunity: A bridge between the thyroid hormone axis and T cell development

Immunity is susceptible to reprogramming by environmental chemical and endocrine signals. Notably, numerous thyroid disrupting chemicals (TDCs) have the potential to perturb immune endpoints, but data are lacking on the mechanisms by which TDCs can influence the development of the immune system. T cell immunity is particularly vulnerable to modulation by TDCs during thymic education, differentiation, and selection. The following review discusses the ways in which thyroid hormones may influence T cell development, as well as emerging TDCs with potential to impact both thyroid hormone physiology and immune outcomes. To overcome the challenges of studying TDC impacts on immune toxicological endpoints, a comparative approach using the amphibian Xenopus laevis is recommended. X. laevis are ideally suited to studying TDC impacts on immunity due to the importance of thyroid hormones for metamorphosis, and the wealth of immunological models to measure immune endpoints in both tadpoles and adult frogs.

Developmental Exposure to Endocrine Disrupter DDT Interferes with Age-Related Involution of Thymus

The impact of endocrine-disrupting chemicals on the development and involution of the immune system is a possible reason for the increased incidence of disorders associated with inappropriate immune function. The thymus is a lymphoid and also an endocrine organ, and, accordingly, its development and functioning may be impaired by endocrine disruptors. The aim was to evaluate age-related thymus involution in mature rats exposed to the endocrine disruptor DDT during prenatal and postnatal ontogeny. Methodology included in vivo experiment on male Wistar rats exposed to low doses of DDT during prenatal and postnatal development and morphological assessment of thymic involution, including the immunohistochemical detection of proliferating thymocytes. The study was carried out at the early stage of involution. Results: DDT-exposed rats exhibited a normal anatomy, and the relative weight of the thymus was within the control ranges. Histological and immunohistochemical examinations revealed increased cellularity of the cortex and the medulla, higher content of lymphoblasts, and more intensive proliferation rate of thymocytes compared to the control. Evaluation of thymic epithelial cells revealed a higher rate of thymic corpuscles formation. Conclusion: The data obtained indicate that endocrine disrupter DDT disturbs postnatal development of the thymus. Low-dose exposure to DDT during ontogeny does not suppress growth rate but violates the developmental program of the thymus by slowing down the onset of age-related involution and maintaining high cell proliferation rate. It may result in excessive formation of thymus-dependent areas in peripheral lymphoid organs and altered immune response.

Toxic Effects of Endocrine Disruptor Exposure on Collagen-Induced Arthritis

Endocrine disruptors (EDs) are chemical substances capable of affecting endocrine system functioning and interfering with organ morphogenesis and physiological functions. The development and regeneration of bone tissues have a complex hormonal regulation, and therefore, bone tissue cells can be considered potential targets for endocrine disruptors. In that regard, the aim of this research was to investigate the impact of ED exposure on the inflammatory response and oxidative stress in an experimental model of collagen-induced arthritis (CIA). Arthritis was induced by an emulsion of type II collagen (CII) and complete Freund’s adjuvant, which was administered intradermally on days 0 and 21. Mice from day 21 to day 35 received the following EDs by oral gavage: cypermethrin (CP), diethyl phthalate (DEP), vinclozolin (VCZ), 17α-ethinylestradiol (EE), perfluorooctanesulfonic acid (PFOS) and atrazine (ATR). ED exposure caused worsening of clinical signs (erythema and edema in the hind paws), histological and radiographic changes, as well as behavioral deficits, induced by CII injections. Furthermore, ED exposure significantly increased the degree of inflammation and oxidative damage induced by arthritis; this upregulation was more evident after exposure to ATR than to other EDs. The results from our study suggest that exposure to EDs may play a deleterious role in the progression of RA; therefore, exposure to EDs should be limited.

Impact of polypropylene microplastics and chemical pollutants on European sea bass (Dicentrarchus labrax) gut microbiota and health

Plastic pollution has become a global problem for marine ecosystems. Microplastics (MPs) are consumed by several marine organisms, including benthic and pelagic fish species that confuse them with food sources, thus contributing to bioaccumulation along the food chain. In addition to structural intestinal damage, ingestion of MPs represents a pathway for fish exposure to potentially hazardous chemicals, too. Most of them are endocrine disrupters, genotoxic or induce immune depression in fish. Accordingly, we assessed the combined toxicological effects of microplastics (MPs) and adsorbed pollutants by adding them to marine fish diet. European sea bass (Dicentrarchus labrax) juveniles were fed for 60 days with feeds containing polypropylene MPs, either virgin or contaminated with chemical pollutants (a blend of dichlorodiphenyldichloroethylene, chlorpyrifos, and benzophenone-3). The data demonstrated a synergic action of MPs and chemical pollutants to induce an inflammatory-like response in distal intestine of sea bass as shown by the up regulation of cytokine il-6 and tnf-α expression. Morphological analysis detected the presence of a focus of lymphocytes in anterior and posterior intestinal segments of fish fed with contaminants in the diet. With regard to microbiota, significant changes in bacterial species richness, beta diversity, and composition of gut microbiota were observed as a consequence of both pollutants and polluted MPs ingestion. These perturbations in gut microbial communities, including the reduction of beneficial lactic acid bacteria and the increase in potential pathogenic microorganism (Proteobacteria and Vibrionales), were undeniable signs of intestinal dysbiosis, which in turn confirmed the signs of inflammation caused by pollutants, especially when combined with MPs. The results obtained in this study provide, therefore, new insights into the potential risks of ingesting MPs as pollutant carriers in marine fish.

EDC-induced mechanisms of immunotoxicity: a systematic review

Endocrine-disrupting chemicals (EDCs) refer to a group of chemicals that cause adverse effects in human health, impairing hormone production and regulation, resulting in alteration of homeostasis, reproductive, and developmental, and immune system impairments. The immunotoxicity of EDCs involves many mechanisms altering gene expression that depend on the activation of nuclear receptors such as the aryl hydrocarbon receptor (AHR), the estrogen receptor (ER), and the peroxisome proliferator-activated receptor (PPAR), which also results in skin and intestinal disorders, microbiota alterations and inflammatory diseases. This systematic review aims to review different mechanisms of immunotoxicity and immunomodulation of T cells, focusing on T regulatory (Treg) and Th17 subsets, B cells, and dendritic cells (DCs) caused by specific EDCs such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), bisphenols (BPs) and polyfluoroalkyl substances (PFASs). To achieve this objective, a systematic study was conducted searching various databases including PubMed and Scopus to find in-vitro, in-vivo, and biomonitoring studies that examine EDC-dependent mechanisms of immunotoxicity. While doing the systematic review, we found species- and cell-specific outcomes and a translational gap between in-vitro and in-vivo experiments. Finally, an adverse outcome pathway (AOP) framework is proposed, which explains mechanistically toxicity endpoints emerging from different EDCs having similar key events and can help to improve our understanding of EDCs mechanisms of immunotoxicity. In conclusion, this review provides insights into the mechanisms of immunotoxicity mediated by EDCs and will help to improve human health risk assessment.

An ancestral nuclear receptor couple, PPAR-RXR, is exploited by organotins

Environmental chemicals have been reported to greatly disturb the endocrine and metabolic systems of multiple animal species. A recent example involves the exploitation of the nuclear receptor (NR) heterodimeric pair composed by PPAR/RXR (peroxisome proliferator-activated receptor/retinoid X receptor), which shows lipid perturbation in mammalian species. While gene orthologues of both of these receptors have been described outside vertebrates, no functional characterization of PPAR has been carried in protostome lineages. We provide the first functional analysis of PPAR in Patella sp. (Mollusca), using model obesogens such as tributyltin (TBT), triphenyltin (TPT), and proposed natural ligands (fatty acid molecules). To gain further insights, we used site-directed mutagenesis to PPAR and replaced the tyrosine 277 by a cysteine (the human homologous amino acid and TBT anchor residue) and an alanine. Additionally, we explored the alterations in the fatty acid profiles after an exposure to the model obesogen TBT, in vivo. Our results show that TBT and TPT behave as an antagonist of Patella sp. PPAR/RXR and that the tyrosine 277 is important, but not essential in the response to TBT. Overall, these results suggest a relation between the response of the mollusc PPAR-RXR to TBT and the lipid profile alterations reported at environmentally relevant concentrations. Our findings highlight the importance of comparative analysis between protostome and deuterostome lineages to decipher the differential impact of environmental chemicals.

Impact of phthalates and bisphenols plasticizers on haemocyte immune function of aquatic invertebrates: A review on physiological, biochemical, and genomic aspects

The invertebrate innate immunity is a crucial characteristic that represents a valuable basis for studying common biological responses to environmental pollutants. Cell defence mechanisms are key players in protecting the organism from infections and foreign materials. Many haemocyte-associated immunological parameters have been reported to be immunologically sensitive to aquatic toxins (natural or artificial). Environmental plastic pollution poses a global threat to ecosystems and human health due to plastic vast and extensive use as additives in various consumer products. In recent years, studies have been done to evaluate the effects of plasticizers on humans and the environment, and their transmission and presence in water, air, and indoor dust, and so forth. Hence, the development of biomarkers that evaluate biological responses to different pollutants are essential to obtain important information on plasticizers' sublethal effects. This review analyses the current advances in the adverse effects of plasticizers (as emerging contaminants), such as immunological response disruption. The review also shows a critical analysis of the effects of the most widely used plasticizers on haemocytes. The advantages of an integrative approach that uses chemical, genetic, and immunomarker assays to monitor toxicity are highlighted. All these factors are imperative to ponder when designing toxicity studies to recognize the potential effects of plasticizers like bisphenol A and phthalates.

Contemporary Techniques for Remediating Endocrine-Disrupting Compounds in Various Water Sources: Advances in Treatment Methods and Their Limitations

Over the years, the persistent occurrence of superfluous endocrine-disrupting compounds (EDCs) (sub µg L⁻¹) in water has led to serious health disorders in human and aquatic lives, as well as undermined the water quality. At present, there are no generally accepted regulatory discharge limits for the EDCs to avert their possible negative impacts. Moreover, the conventional treatment processes have reportedly failed to remove the persistent EDC pollutants, and this has led researchers to develop alternative treatment methods. Comprehensive information on the recent advances in the existing novel treatment processes and their peculiar limitations is still lacking. In this regard, the various treatment methods for the removal of EDCs are critically studied and reported in this paper. Initially, the occurrences of the EDCs and their attributed effects on humans, aquatic life, and wildlife are systematically reviewed, as well as the applied treatments. The most noticeable advances in the treatment methods include adsorption, catalytic degradation, ozonation, membrane separation, and advanced oxidation processes (AOP), as well as hybrid processes. The recent advances in the treatment technologies available for the elimination of EDCs from various water resources alongside with their associated drawbacks are discussed critically. Besides, the application of hybrid adsorption–membrane treatment using several novel nano-precursors is carefully reviewed. The operating factors influencing the EDCs’ remediations via adsorption is also briefly examined. Interestingly, research findings have indicated that some of the contemporary techniques could achieve more than 99% EDCs removal.

Genome-wide DNA methylation of the liver reveals delayed effects of early-life exposure to 17-α-ethinylestradiol in the self-fertilizing mangrove rivulus

Organisms exposed to endocrine disruptors in early life can show altered phenotype later in adulthood. Although the mechanisms underlying these long-term effects remain poorly understood, an increasing body of evidence points towards the potential role of epigenetic processes. In the present study, we exposed hatchlings of an isogenic lineage of the self-fertilizing fish mangrove rivulus for 28 days to 4 and 120 ng/L of 17-α-ethinylestradiol. After a recovery period of 140 days, reduced representation bisulphite sequencing (RRBS) was performed on the liver in order to assess the hepatic genome-wide methylation landscape. Across all treatment comparisons, a total of 146 differentially methylated fragments (DMFs) were reported, mostly for the group exposed to 4 ng/L, suggesting a non-monotonic effect of EE2 exposure. Gene ontology analysis revealed networks involved in lipid metabolism, cellular processes, connective tissue function, molecular transport and inflammation. The highest effect was reported for nipped-B-like protein B (NIPBL) promoter region after exposure to 4 ng/L EE2 (+ 21.9%), suggesting that NIPBL could be an important regulator for long-term effects of EE2. Our results also suggest a significant role of DNA methylation in intergenic regions and potentially in transposable elements. These results support the ability of early exposure to endocrine disruptors of inducing epigenetic alterations during adulthood, providing plausible mechanistic explanations for long-term phenotypic alteration. Additionally, this work demonstrates the usefulness of isogenic lineages of the self-fertilizing mangrove rivulus to better understand the biological significance of long-term alterations of DNA methylation by diminishing the confounding factor of genetic variability.

Physiological and metabolic approach of plastic additive effects: Immune cells responses

Human and wildlife are continually exposed to a wide range of compounds and substances, which reach the body through the air, water, food, or personal care products. Plasticizers are compounds added to plastics and can be released to the environment under certain conditions. Toxicological studies have concluded that plasticizers, phthalates, and bisphenols are endocrine disruptors, alter the endocrine system and functioning of the immune system and metabolic process. A functional immune response indicates favourable living conditions for an organism; conversely, a weak immune response could reveal a degraded environment that requires organisms to adapt. There is growing concern about the presence of plastic debris in the environment. In this review, the current knowledge of the action of plasticizers on leukocyte cells will be itemized. We also point out critically the role of some nuclear and membrane receptors as key players in the action of plasticizers on cells possess immune function. We discuss the role of erythrocytes within the immune responses and the alteration caused by plasticizers. Finally, we highlight data evidencing mitochondrial dysfunctions triggered by plasticizing toxic action, which can lead to immunosuppression.

A novel use of the leukocyte coping capacity assay to assess the immunomodulatory effects of organohalogenated contaminants in avian wildlife

Apex predators are characterized by high levels of biomagnifying organohalogenated contaminants (OHCs) which have been found to induce detrimental health effects in wildlife, such as immune system impairment. The leukocyte coping capacity (LCC) assay is a functional real-time measure of an innate immune response essential in pathogen resistance, known as the respiratory burst. The current study suggests the novel use of this tool to test whether OHCs impair the innate immune system of a sentinel top predator, the white-tailed eagle (Haliaeetus albicilla; WTE). The LCC analysis was performed in the field on WTE nestlings (n = 84) from northern Norway over two breeding seasons. Poly- and perfluoroalkyl substances (PFAS) dominated the total OHC load, surpassing the levels of legacy organochlorines. In addition, we detected significant negative correlations between concentrations of all polychlorinated biphenyls, p,p'-dichlorodiphenyldichloroethylene, perfluorohexane sulfonic acid and long-chain perfluorocarboxylic acids and the LCC of WTE nestlings. Based on our current findings reflecting a potential negative effect of both emerging and legacy OHCs on innate immune capacity, we suggest LCC to be a relevant and accessible test expanding the ecotoxicological toolbox to assess sub-lethal effects of OHCs in apex avian wildlife.

How microplastic components influence the immune system and impact on children health: Focus on cancer

BACKGROUND

As a result of human socioeconomic activity, industrial wastes have increased distressingly. Plastic pollution is globally distributed across the world due to its properties of buoyancy and durability. A big health hazard is the sorption of toxicants to plastic while traveling through the environment. Two broad classes of plastic-related chemicals are of critical concern for human health-bisphenols and phthalates. Bisphenol A (BPA) is an endocrine-disruptor compound (EDC) with estrogenic activity. It is used in the production of materials that are used daily. The endocrine modulating activity of BPA and its effects on reproductive health has been widely studied. BPA also has effects on the immune system; however, they are poorly investigated and the available data are inconclusive. Phthalates are also EDCs used as plasticizers in a wide array of daily-use products. Since these compounds are not covalently bound to the plastic matrix, they easily leach out from it, leading to high human exposure. These compounds exert several cell effects through modulating different endocrine pathways, such as estrogen, androgen, peroxisome proliferator-activated receptor gamma, and arylhydrocarbon receptor pathways. The exposure to both classes of plastic derivatives during critical periods has detrimental effects on human health.

METHODS

In this review, we have compiled the most important of their perinatal effects on the function of the immune system and their relationship to the development of different types of cancer.

RESULTS/CONCLUSION

The administration of bisphenols and phthalates during critical stages of development affects important immune system components, and the immune function; which might be related to the development of different diseases including cancer.

Developmental exposure to a mixture of unconventional oil and gas chemicals: A review of experimental effects on adult health, behavior, and disease

Unconventional oil and natural gas extraction (UOG) combines directional drilling and hydraulic fracturing and produces billions of liters of wastewater per year. Herein, we review experimental studies that evaluated the potential endocrine-mediated health impacts of exposure to a mixture of 23 UOG chemicals commonly found in wastewater. The purpose of this manuscript is to synthesize and summarize a body of work using the same UOG-mix but with different model systems and physiological endpoints in multiple experiments. The studies reviewed were conducted in laboratory animals (mice or tadpoles) and human tissue culture cells. A key feature of the in vivo studies was the use of four environmentally relevant doses spanning three orders of magnitude ranging from concentrations found in surface and ground water in UOG dense areas to concentrations found in UOG wastewater. This UOG-mix exhibited potent antagonist activity for the estrogen, androgen, glucocorticoid, progesterone, and thyroid receptors in human tissue culture cells. Subsequently, pregnant mice were administered the UOG-mix in drinking water and offspring were examined in adulthood or to tadpoles. Developmental exposure profoundly impacted pituitary hormone concentrations, reduced sperm counts, altered folliculogenesis, and increased mammary gland ductal density and preneoplastic lesions in mice. It also altered energy expenditure, exploratory and risk-taking behavior, the immune system in three immune models in mice, and affected basal and antiviral immunity in frogs. These findings highlight the diverse systems affected by developmental EDC exposure and the need to examine human and animal health in UOG regions.

Exposure to bisphenols and asthma morbidity among low-income urban children with asthma

BACKGROUND

Bisphenol A (BPA) has been linked with pediatric asthma development and allergic airway inflammation in animal models. Whether exposure to BPA or its structural analogs bisphenol S (BPS) and bisphenol F (BPF) is associated with asthma morbidity remains unknown.

OBJECTIVE

We examined associations between bisphenols and morbidity due to pediatric asthma.

METHODS

We quantified concentrations of BPA, BPS, and BPF in 660 urine samples from 148 predominantly low-income, African American children (aged 5-17 years) with established asthma. We used biobanked biospecimens and data on symptoms, health care utilization, and pulmonary function and inflammation that were collected every 3 months over the course of a year. We used generalized estimating equations to examine associations between concentrations or detection of urinary bisphenols and morbidity outcomes and assessed heterogeneity of associations by sex.

RESULTS

We observed consistent positive associations between BPA exposure and measures of asthma morbidity. For example, we observed increased odds of general symptom days (adjusted odds ratio [aOR] = 1.40 [95% C = 1.02-1.92]), maximal symptom days (aOR = 1.36 [95% CI = 1.00-1.83]), and emergency department visits (aOR = 2.12 [95% CI =1.28-3.51]) per 10-fold increase in BPA concentration. We also observed evidence of sexually dimorphic effects; BPA concentrations were associated with increased odds of symptom days and health care utilization only among boys. Findings regarding BPS and BPF did not consistently point to associations with asthma symptoms or health care utilization.

CONCLUSION

We found evidence to suggest that BPA exposure in a predominantly low-income, minority pediatric cohort is associated with asthma morbidity and that associations may differ by sex. Our findings support additional studies, given the high pediatric asthma burden and widespread exposure to BPA in the United States.

Defining Parallels between the Salivary Glands and Pancreas to Better Understand Pancreatic Carcinogenesis

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant tumor with a dismal prognosis, largely due to its late presentation. Methods for early detection, the development of reliable screening tools, and the identification of sensitive and specific biomarkers have remained essential research priorities to improve early patient management and outcomes. The pancreas and salivary glands share histological and functional similarities, and the salivary glands have demonstrated a role in oral and systemic health. This review focuses on the similarities and differences between the pancreas and salivary glands and how these can inform our understanding of PDAC genesis and early diagnosis. In particular, chemical exposure, which alters salivary gland gene transcription and morphogenesis, may not only directly impact salivary gland regulation but alter pancreatic function via the systemic secretion of growth hormones. Diabetes and obesity are associated with an increased risk of pancreatic cancer, and a link between chemical exposure and the development of diabetes, obesity, and consequently PDAC genesis is proposed. Possible mechanisms include altering salivary or pancreatic morphology and organ function, disrupting endocrine signaling, or altering pro-inflammatory homeostasis. Finally, saliva contains putative specific biomarkers that show promise as non-invasive diagnostic tools for PDAC.

Development of Proliferative Response of Thymic Lymphocytes to T-Cell Mitogen in Rats Exposed to Endocrine Disrupter DDT during Ontogeny

We studied the formation of proliferative response of thymic lymphocytes to T-cell mitogen in rats exposed to endocrine disrupter DDT during prenatal and postnatal ontogeny. Developmental exposure to the endocrine disruptor was found to attenuate proliferative response during puberty and adulthood due to maintenance of higher proliferation rate of thymic lymphocytes in comparison with age-matched controls. Insufficient proliferative response to mitogens in rats developmentally exposed to the endocrine disrupter increases the risk of impairment of cell-mediated reactions of adaptive immunity.

Lung inflammation induced by exposure to Bisphenol-A is associated with mTOR-mediated autophagy in adolescent mice

Epidemiologic studies show that there is a link between Bisphenol A (BPA) exposure and lung inflammation. Despite this, the molecular mechanisms are not entirely known. This study sought to determine whether exposure to BPA affected the development of ovalbumin (OVA) induced lung inflammation in adolescent female mice and whether the mechanism was related to mTOR-mediated autophagy pathway. Female 4-week-old C57BL/6 mice after one week of domestication were randomly divided into five groups (8/group): control group, OVA group, 0.1 μg mL^-1 BPA + OVA group, 0.2 μg mL^-1 BPA + OVA group and 0.4 μg mL^-1 BPA + OVA group. BPA exacerbated airway hyperresponsiveness (AHR), induced the pathological changes in the lung, which also enhanced inflammatory cells and cytokine levels. In addition, BPA exposure affected expression of autophagy associated proteins and genes. This research results indicated that BPA aggravated OVA-induced lung inflammation and induced abnormal immune function in mice, and its mechanism was related to the activation of autophagy pathway by down-regulation expression of mTOR. These findings suggest that therapeutic strategies to target autophagy may offer a new approach for severe asthma therapy.

Effect of estrogen-active compounds on the expression of RACK1 and immunological implications

We previously demonstrated the existence of a balance among steroid hormones, i.e. glucocorticoids and androgens, in RACK1 (receptor for activated C kinase 1) expression and innate immunity activation, which may offer the opportunity to use RACK1 expression as marker to evaluate immunotoxicity of hormone-active substances. Because of the existence of close interconnections between the different steroid hormone receptors with overlapping ligand specificities and signaling pathways, in this study, we wanted to investigate a possible effect of estrogenic active compounds, namely 17β-estradiol, diethylstilbestrol, and zearalenone, on RACK-1 expression and innate immune responses using THP-1 cells as experimental model. All compounds increased RACK1 transcriptional activity as evaluated by reporter luciferase activity, mRNA expression as assessed by real time-PCR and protein expression by western blot analysis, which paralleled an increase in LPS-induced IL-8, TNF-α production, and CD86 expression, which we previously demonstrated to be dependent on RACK1/PKCβ activation. As the induction of RACK1 expression can be blocked by the antagonist G15, induced by the agonist G1 and by the non-cell permeable 17β-estradiol conjugated with BSA, a role of GPER (previously named GPR30) activation in estrogen-induced RACK1 expression could be demonstrated. In addition, a role of androgen receptor (AR) in RACK1 transcription was also demonstrated by the ability of flutamide, a nonsteroidal antiandrogen, to completely prevent diethylstilbestrol-induced RACK1 transcriptional activity and protein expression. Altogether, our data suggest that RACK1 may represent an interesting target of steroid-active compounds, and its evaluation may offer the opportunity to screen the immunotoxic potential of hormone-active substances.

Phthalate Exposure During the Prenatal and Lactational Period Increases the Susceptibility to Rheumatoid Arthritis in Mice

The prenatal and early postnatal period is highly sensitive to environmental exposures that may interfere with the developmental programming of the immune system leading to an altered disease risk in later life. To clarify the role of early influences in activation or exacerbation of autoimmune diseases like rheumatoid arthritis (RA) we investigated the effect of maternal exposure during the prenatal and lactational period of DBA/1 mice to the plasticizer benzyl butyl phthalate (BBP) on the development of RA in the offspring. Using a mild collagen-induced arthritis (CIA) model, maternal BBP-exposure increased both the prevalence and the severity of RA in the progeny compared to un-exposed dams. Additionally, maternal BBP exposure led to elevated serum IgG₁ and IgG_2a level in the offspring and increased the IFN-γ and IL-17 release from collagen-re-stimulated spleen cells. Transcriptome analysis of splenocytes isolated from 3-week-old pups before RA-induction revealed considerable changes in gene expression in the offspring from BBP-exposed dams. Among them were regulator of G-protein signaling 1 (rgs1), interleukin-7 receptor (il-7r) and CXC chemokine 4 (cxcr4), all genes that have previously been described as associated with RA pathology. In summary, our results demonstrate that perinatal exposure to BBP increases the susceptibility of the offspring to RA, probably via a phthalate-induced disturbed regulation of RA-relevant genes or signaling pathways.

Developmental exposure to low doses of dichlorodiphenyltrichloroethane impairs proliferative response of thymic lymphocytes to Concanavalin A in rats

The aim of the research was to study formation of thymic lymphocytes proliferative response to T cell mitogen Concanavalin A in 7, 42, and 70 days-old male Wistar rats developmentally exposed to low doses of endocrine disruptor dichlorodiphenyltrichloroethane (2.90 ± 0.13 μg/kg body weight). The thymus of the exposed rats did not show morphological abnormalities. Exposure to the endocrine disrupter was found to alter age-dependent changes of thymic lymphocyte proliferative activity and attenuate proliferative response to Concanavalin A in puberty and adulthood. Insufficient response to mitogen was mediated by higher content of actively proliferating Ki-67-positive lymphoblasts compared to the control values. Insufficient proliferative response to mitogen in developmentally exposed to the endocrine disruptor rats may provide higher risk of impaired cellular immune reactions.

Urban-level environmental factors related to pediatric asthma

During the 20th century, urbanization has increasing and represented a major demographic and environmental change in developed countries. This ever-changing urban environment has an impact on disease patterns and prevalence, namely on noncommunicable diseases, such as asthma and allergy, and poses many challenges to understand the relationship between the changing urban environment and the children health. The complex interaction between human beings and urbanization is dependent not only on individual determinants such as sex, age, social or economic resources, and lifestyles and behaviors, but also on environment, including air pollution, indoors and outdoors, land use, biodiversity, and handiness of green areas. Therefore, the assessment and identification of the impact of urban environment on children's health have become a priority and many recent studies have been conducted with the goal of better understanding the impacts related to urbanization, characterizing indoor air exposure, identifying types of neighborhoods, or characteristics of neighborhoods that promote health benefits. Thus, this review focuses on the role of urban environmental factors on pediatric asthma.

Concentration-dependent effects of 17β-estradiol and bisphenol A on lipid deposition, inflammation and antioxidant response in male zebrafish (Danio rerio)

Environmental estrogenic compounds are important pollutants, which are widely distributed in natural water bodies. They produce various adverse effects on fish, but their concentration-dependent toxicities in fish metabolism and health are not fully understood. This study investigated the effects of 17β-estradiol (E2) and bisphenol A (BPA) at low and high concentrations on lipid deposition, inflammation and antioxidant response in male zebrafish. We measured fish growth parameters, gonad development, lipid contents and the activities of inflammatory and antioxidant enzymes, as well as their mRNA expressions. All E2 and BPA concentrations used increased body weight, damaged gonad structure and induced feminization in male zebrafish. The exposure of zebrafish to E2 and BPA promoted lipid accumulation by increasing total fat, liver triglycerides and free fatty acid contents, and also upregulated lipogenic genes expression, although they decreased total cholesterol content. Notably, zebrafish exposed to low concentrations of E2 (200 ng/L) and BPA (100 μg/L) had higher lipid synthesis and deposition compared to high concentrations (2000 ng/L and 2000 μg/L, respectively). However, the high concentrations of E2 and BPA increased inflammation and antioxidant response. Furthermore, BPA caused greater damage to fish gonad development and more severe lipid peroxidation compared to E2. Overall, the results suggest that the toxic effects of E2 and BPA on zebrafish are concentration-dependent such that, the relative low concentrations used induced lipid deposition, whereas the high ones caused adverse effects on inflammation and antioxidant response.

The Effects of Endocrine Disrupting Chemicals on Biomarkers of Inflammation Produced by Lipopolysaccharide Stimulated RAW264.7 Macrophages

Endocrine disrupting chemicals (EDCs) are common pollutants in the environment and can induce disruption of the endocrine and immune systems. The present study evaluated the effects of selected common environmental EDCs on secretion of inflammatory biomarkers by RAW264.7 cells. The EDCs investigated were Estradiol (E2), 5α-dihydrotestosterone (DHT), and Bisphenol A (BPA). To evaluate if the effects caused by EDCs were modulated by steroid hormone receptors, antagonists of estrogen and androgen receptors were used. The steroid receptor antagonists used were Tamoxifen, an estrogen receptor antagonist, and Flutamide, an androgen receptor antagonist. Secretion of biomarkers of inflammation, namely nitric oxide (NO) and interleukin 6 (IL-6), were monitored. The NO was determined using Griess reaction and IL-6 was measured by enzyme linked immunosorbent assay (ELISA). Although 5 μg/mL E2, DHT, and BPA were not toxic to RAW264.7 cell cultures, the same treatments significantly (p < 0.001) reduced both NO and IL-6 secretion by lipopolysaccharide (LPS)-stimulated RAW264.7 cell cultures. The suppression of NO and IL-6 secretion indicate inhibition of inflammation by DHT, E2, and BPA. The inhibitory effects of DHT, E2 and BPA are partially mediated via their cellular receptors, because the effects were reversed by their respective receptor antagonists. Flutamide reversed the effects of DHT, while Tamoxifen reversed the effects of E2 and BPA. In conclusion, E2, BPA, and DHT inhibit the synthesis of inflammation biomarkers by LPS-stimulated RAW264.7 cells. The inhibitory effects of EDCs can be partially reversed by the addition of an estrogen receptor antagonist for E2 and BPA, and an androgenic receptor antagonist for DHT. The inhibition of inflammatory response in stimulated RAW264.7 cells may be a useful bioassay model for monitoring estrogenic and androgenic pollutants.

Exposure to indoor endocrine-disrupting chemicals and childhood asthma and obesity

BACKGROUND

Indoor air contaminants may act as endocrine-disrupting chemicals (EDCs). However, to what extent these contaminants affect health is poorly known. We aimed to assess the association between EDCs exposure and asthma, respiratory symptoms and obesity in schoolchildren.

METHODS

Data from a cross-sectional analysis of 815 participants from 20 schools in Porto, Portugal, were analysed. Symptoms were assessed, asthma was defined on lung function, and airway reversibility and body mass index (BMI) were calculated. The concentrations of 13 volatile organic compounds and 2 aldehydes identified as EDCs were measured in 71 classrooms throughout 1 week. Principal component analysis (PCA) was used to assess the effect of co-exposure. Associations were estimated by regression coefficients using linear and logistic regression models.

RESULTS

Increased individual and combined EDCs levels were found in classrooms having more children with asthma and obesity. Higher levels of hexane, styrene, cyclohexanone, butylated hydroxytoluene and 2-butoxyethanol were associated with obesity, and higher levels of cyclohexanone were associated with increased child BMI. Toluene, o-xylene, m/p-xylene and ethylbenzene were significantly associated with nasal obstruction. A positive association was found between PC1 and the risk of obese asthma (OR = 1.43, 95% CI 1.01, 1.98) and between PC2 and overweight (OR = 1.51, 95% CI 1.28, 1.79). PC1 and PC2 were also associated with nasal obstruction, and PC2 was associated with breathing difficulties and lean body mass, although EDCs concentrations were low.

CONCLUSIONS

Our findings further support the role of EDCs in asthma and obesity development. Moreover, even low levels of indoor exposure may influence the risk of asthma, respiratory symptoms and obesity.

Developmental exposure to chemicals associated with unconventional oil and gas extraction alters immune homeostasis and viral immunity of the amphibian Xenopus

Although aquatic vertebrates and humans are increasingly exposed to water pollutants associated with unconventional oil and gas extraction (UOG), the long-term effects of these pollutants on immunity remains unclear. We have established the amphibian Xenopus laevis and the ranavirus Frog Virus 3 (FV3) as a reliable and sensitive model for evaluating the effects of waterborne pollutants. X. laevis tadpoles were exposed to a mixture of equimass amount of UOG chemicals with endocrine disrupting activity (0.1 and 1.0 μg/L) for 3 weeks, and then long-term effects on immune function at steady state and following viral (FV3) infection was assessed after metamorphosis. Notably, developmental exposure to the mixture of UOG chemicals at the tadpole stage affected metamorphic development and fitness by significantly decreasing body mass after metamorphosis completion. Furthermore, developmental exposure to UOGs resulted in perturbation of immune homeostasis in adult frogs, as indicated by significantly decreased number of splenic innate leukocytes, B and T lymphocytes; and a weakened antiviral immune response leading to increased viral load during infection by the ranavirus FV3. These findings suggest that mixture of UOG-associated waterborne endocrine disruptors at low but environmentally-relevant levels have the potential to induce long-lasting alterations of immune function and antiviral immunity in aquatic vertebrates and ultimately human populations.

Hormesis and immunity: A review

The hormesis concept demonstrates that in contrast to the toxic effect of high doses of materials, irradiation, etc., low doses of them are beneficial and, in addition, help to eliminate (prevent) the deleterious effect of high doses given after it. By this effect, it is an important factor of (human) evolution protecting man from harmful impacts, similarly to the role of immunity. However, immunity is also continuously influenced by hormetic effects of environmental [chemical (pollutions), physical (background irradiations and heat), etc.] and medical (drugs and therapeutic irradiations) and food interactions. In contrast to earlier beliefs, the no-threshold irradiation dogma is not valid in low-dose domains and here the hormesis concept is valid. Low-dose therapeutic irradiation, as well as background irradiations (by radon spas or moderately far from the epicenter of atomic bomb or nuclear facilities), is rather beneficial than destructive and the fear from them seems to be unreasonable from immunological point of view. Practically, all immune parameters are beneficially influenced by all forms of low-dose radiations.

Early-life exposure to the endocrine disruptor 17-α-ethinylestradiol induces delayed effects in adult brain, liver and ovotestis proteomes of a self-fertilizing fish

Early-life represents a critically sensitive window to endocrine disrupting chemicals, potentially leading to long-term repercussions on the phenotype later in life. The mechanisms underlying this phenomenon, referred to as the Developmental Origins of Health and Disease (DOHaD), are still poorly understood. To gain molecular understanding of these effects, we exposed mangrove rivulus (Kryptolebias marmoratus) for 28 days post hatching (dph) to 4 and 120 ng/L 17-α-ethinylestradiol, a model xenoestrogen. After 28 days, fish were raised for 140 days in clean water and we performed quantitative label-free proteomics on brain, liver and ovotestis of 168 dph adults. A total of 820, 888 and 420 proteins were robustly identified in the brain, liver and ovotestis, respectively. Effects of 17-α-ethinylestradiol were tissue and dose-dependent: a total of 31, 51 and 18 proteins were differentially abundant at 4 ng/L in the brain, liver and ovotestis, respectively, compared to 20, 25 and 39 proteins at 120 ng/L. Our results suggest that estrogen-responsive pathways, such as lipid metabolism, inflammation, and the innate immune system were affected months after the exposure. In addition, the potential perturbation of S-adenosylmethionine metabolism encourages future studies to investigate the role of DNA methylation in mediating the long-term effects of early-life exposures. SIGNIFICANCE: The Developmental Origins of Health and Disease (DOHaD) states that early life stages of humans and animals are sensitive to environmental stressors and can develop health issues later in life, even if the stress has ceased. Molecular mechanisms supporting DOHaD are still unclear. The mangrove rivulus is a new fish model species naturally reproducing by self-fertilization, making it possible to use isogenic lineages in which all individuals are highly homozygous. This species therefore permits to strongly reduce the confounding factor of genetic variability in order to investigate the effects of environmental stress on the phenotype. After characterizing the molecular phenotype of brain, liver and ovotestis, we obtained true proteomic reaction norms of these three organs in adults after early life stages have been exposed to the common endocrine disruptor 17-α-ethinylestradiol (EE2). Our study demonstrates long-term effects of early-life endocrine disruption at the proteomic level in diverse estrogen-responsive pathways 5 months after the exposure. The lowest tested and environmentally relevant concentration of 4 ng/L had the highest impact on the proteome in brain and liver, highlighting the potency of endocrine disruptors at low concentrations.

Role of Endocrine-Disrupting Engineered Nanomaterials in the Pathogenesis of Type 2 Diabetes Mellitus

Nanotechnology has enabled the development of innovative technologies and products for several industrial sectors. Their unique physicochemical and size-dependent properties make the engineered nanomaterials (ENMs) superior for devising solutions for various research and development sectors, which are otherwise unachievable by their bulk forms. However, the remarkable advantages mediated by ENMs and their applications have also raised concerns regarding their possible toxicological impacts on human health. The actual issue stems from the absence of systematic data on ENM exposure-mediated health hazards. In this direction, a comprehensive exploration on the health-related consequences, especially with respect to endocrine disruption-related metabolic disorders, is largely lacking. The reasons for the rapid increase in diabetes and obesity in the modern world remain largely unclear, and epidemiological studies indicate that the increased presence of endocrine disrupting chemicals (EDCs) in the environment may influence the incidence of metabolic diseases. Functional similarities, such as mimicking natural hormonal actions, have been observed between the endocrine-disrupting chemicals (EDCs) and ENMs, which supports the view that different types of NMs may be capable of altering the physiological activity of the endocrine system. Disruption of the endocrine system leads to hormonal imbalance, which may influence the development and pathogenesis of metabolic disorders, particularly type 2 diabetes mellitus (T2DM). Evidence from many in vitro, in vivo and epidemiological studies, suggests that ENMs generally exert deleterious effects on the molecular/hormonal pathways and the organ systems involved in the pathogenesis of T2DM. However, the available data from several such studies are not congruent, especially because of discrepancies in study design, and therefore need to be carefully examined before drawing meaningful inferences. In this review, we discuss the outcomes of ENM exposure in correlation with the development of T2DM. In particular, the review focuses on the following sub-topics: (1) an overview of the sources of human exposure to NMs, (2) systems involved in the uptake of ENMs into human body, (3) endocrine disrupting engineered nanomaterials (EDENMs) and mechanisms underlying the pathogenesis of T2DM, (4) evidence of the role of EDENMs in the pathogenesis of T2DM from in vitro, in vivo and epidemiological studies, and (5) conclusions and perspectives.

Paraben exposures and asthma-related outcomes among children from the US general population

BACKGROUND

Parabens are synthetic preservatives present in many consumer products. Their antimicrobial and endocrine-disrupting properties have raised concerns that they might play a role in respiratory and allergic diseases; however, studies exploring these associations are scarce.

OBJECTIVE

We examined the cross-sectional association between parabens and asthma morbidity among 450 children with asthma and with asthma prevalence among 4023 children in the US general population participating in the National Health and Nutrition Examination Survey (2005-2014).

METHODS

We conducted multivariable logistic regression to examine associations between urinary paraben biomarker concentrations (butyl paraben, ethyl paraben, methyl paraben [MP], and propyl paraben [PP]) and asthma attacks and emergency department visits among children with asthma and with a current asthma diagnosis among all children. We also examined heterogeneity of associations by sex.

RESULTS

We observed an increased prevalence odds of reporting emergency department visits for every 10-fold increase in MP and PP concentrations among boys with asthma (adjusted prevalence odds ratio, 2.61 [95% CI, 1.40-4.85] and 2.18 [95% CI, 1.22-3.89, respectively; P_{interaction-MP} = .002 and P_{interaction-PP} = .003); associations remained after adjusting for other phenolic compounds previously linked to respiratory outcomes. No other dimorphic effects of exposure by sex were observed. Among children in the general population, no overall associations with current asthma were observed, although there was a positive trend with PP and a current asthma diagnosis.

CONCLUSION

We identified differential effects of exposure to select parabens by sex on asthma morbidity. Further studies are needed to replicate these findings and elucidate mechanisms by which parabens could affect respiratory health and elicit dimorphic effects by sex.

Developmental Exposure to a Mixture of 23 Chemicals Associated With Unconventional Oil and Gas Operations Alters the Immune System of Mice

Chemicals used in unconventional oil and gas (UOG) operations have the potential to cause adverse biological effects, but this has not been thoroughly evaluated. A notable knowledge gap is their impact on development and function of the immune system. Herein, we report an investigation of whether developmental exposure to a mixture of chemicals associated with UOG operations affects the development and function of the immune system. We used a previously characterized mixture of 23 chemicals associated with UOG, and which was demonstrated to affect reproductive and developmental endpoints in mice. C57Bl/6 mice were maintained throughout pregnancy and during lactation on water containing two concentrations of this 23-chemical mixture, and the immune system of male and female adult offspring was assessed. We comprehensively examined the cellularity of primary and secondary immune organs, and used three different disease models to probe potential immune effects: house dust mite-induced allergic airway disease, influenza A virus infection, and experimental autoimmune encephalomyelitis (EAE). In all three disease models, developmental exposure altered frequencies of certain T cell sub-populations in female, but not male, offspring. Additionally, in the EAE model disease onset occurred earlier and was more severe in females. Our findings indicate that developmental exposure to this mixture had persistent immunological effects that differed by sex, and exacerbated responses in an experimental model of autoimmune encephalitis. These observations suggest that developmental exposure to complex mixtures of water contaminants, such as those derived from UOG operations, could contribute to immune dysregulation and disease later in life.

A potential microRNA regulation of immune-related genes in invertebrate haemocytes

Bivalve mollusks have been employed as sentinel organisms in environmental health programs due to their sedentary lifestyle, filter-feeding behavior and their ability to accumulate pathogens or toxin molecules inside tissues. Endocrine disrupting chemicals (EDCs) can be up taken and bioaccumulated, and due to sensibility of mollusks to these EDCs, being able to cause immune alterations. Recently, microRNAs (miRNAs) were shown to be involved in modulation and buffering developmental processes against the effects of environmental alterations and pathogenic microorganisms. Moreover, it is suggested that this miRNAs are incorporated into the estrogen-controlled immune network, regulating mechanism of immune gene expression at the posttranscriptional level, modulating immune responses as phagocytosis, redox reaction and apoptosis in bivalve haemocytes. Thus, miRNAs can be used as biomarkers that specifically elucidate immunotoxic effects caused by exogenous biotic or abiotic factors, and can act as useful tools in integrated monitoring environmental health programs. In this review, we aim to describe the investigations that have been carried out on miRNAs in bivalve mollusks, especially those associated with immune responses against infectious agents and xenobiotic exposure.

Potential Health and Environmental Risks of Three-Dimensional Engineered Polymers

Polymer engineering, such as in three-dimensional (3D) printing, is rapidly gaining popularity, not only in the scientific and medical fields but also in the community in general. However, little is known about the toxicity of engineered materials. Therefore, we assessed the toxicity of 3D-printed and molded parts from five different polymers commonly used for prototyping, fabrication of organ-on-a-chip platforms, and medical devices. Toxic effects of PIC100, E-Shell200, E-Shell300, polydimethylsiloxane, and polystyrene (PS) on early bovine embryo development, on the transactivation of estrogen receptors were assessed, and possible polymer-leached components were identified by mass spectrometry. Embryo development beyond the two-cell stage was inhibited by PIC100, E-Shell200, and E-Shell300 and correlated to the released amount of diethyl phthalate and polyethylene glycol. Furthermore, all polymers (except PS) induced estrogen receptor transactivation. The released materials from PIC100 inhibited embryo cleavage across a confluent monolayer culture of oviduct epithelial cells and also inhibited oocyte maturation. These findings highlight the need for cautious use of engineered polymers for household 3D printing and bioengineering of culture and medical devices and the need for the safe disposal of used devices and associated waste.

Immune System: An Emerging Player in Mediating Effects of Endocrine Disruptors on Metabolic Health

The incidence of metabolic disorders like type 2 diabetes and obesity continues to increase. In addition to the well-known contributors to these disorders, such as food intake and sedentary lifestyle, recent research in the exposure science discipline provides evidence that exposure to endocrine-disrupting chemicals like bisphenol A and phthalates via multiple routes (e.g., food, drink, skin contact) also contribute to the increased risk of metabolic disorders. Endocrine-disrupting chemicals (EDCs) can disrupt any aspect of hormone action. It is becoming increasingly clear that EDCs not only affect endocrine function but also adversely affect immune system function. In this review, we focus on human, animal, and in vitro studies that demonstrate EDC exposure induces dysfunction of the immune system, which, in turn, has detrimental effects on metabolic health. These findings highlight how the immune system is emerging as a novel player by which EDCs may mediate their effects on metabolic health. We also discuss studies highlighting mechanisms by which EDCs affect the immune system. Finally, we consider that a better understanding of the immunomodulatory roles of EDCs will provide clues to enhance metabolic function and contribute toward the long-term goal of reducing the burden of environmentally induced diabetes and obesity.

Exposure to Perfluoroalkyl Substances and Metabolic Outcomes in Pregnant Women: Evidence from the Spanish INMA Birth Cohorts

BACKGROUND

Exposure to perfluoroalkyl substances (PFASs) may increase risk for metabolic diseases; however, epidemiologic evidence is lacking at the present time. Pregnancy is a period of enhanced tissue plasticity for the fetus and the mother and may be a critical window of PFAS exposure susceptibility.

OBJECTIVE

We evaluated the associations between PFAS exposures and metabolic outcomes in pregnant women.

METHODS

We analyzed 1,240 pregnant women from the Spanish INMA [Environment and Childhood Project (INfancia y Medio Ambiente)] birth cohort study (recruitment period: 2003-2008) with measured first pregnancy trimester plasma concentrations of four PFASs (in nanograms/milliliter). We used logistic regression models to estimate associations of PFASs (log₁₀-transformed and categorized into quartiles) with impaired glucose tolerance (IGT) and gestational diabetes mellitus (GDM), and we used linear regression models to estimate associations with first-trimester serum levels of triglycerides, total cholesterol, and C-reactive protein (CRP).

RESULTS

Perfluorooctane sulfonate (PFOS) and perfluorohexane sulfonate (PFHxS) were positively associated with IGT (137 cases) [OR per log₁₀-unit increase=1.99 (95% CI: 1.06, 3.78) and OR=1.65 ( 95% CI: 0.99, 2.76), respectively]. PFOS and PFHxS associations with GDM (53 cases) were in a similar direction, but less precise. PFOS and perfluorononanoate (PFNA) were negatively associated with triglyceride levels [percent median change per log₁₀-unit increase=-5.86% (95% CI: -9.91%, -1.63%) and percent median change per log₁₀-unit increase=-4.75% (95% CI: -8.16%, -0.61%, respectively], whereas perfluorooctanoate (PFOA) was positively associated with total cholesterol [percent median change per log₁₀-unit increase=1.26% (95% CI: 0.01%, 2.54%)]. PFASs were not associated with CRP in the subset of the population with available data (n=640).

CONCLUSIONS

Although further confirmation is required, the findings from this study suggest that PFAS exposures during pregnancy may influence lipid metabolism and glucose tolerance and thus may impact the health of the mother and her child. https://doi.org/10.1289/EHP1062.