Structure-based modeling to assess binding and endocrine disrupting potential of polycyclic aromatic hydrocarbons in Daniorerio.

Environmental contaminants, such as polycyclic aromatic hydrocarbons (PAHs), have raised concerns regarding their potential endocrine-disrupting effects on aquatic organisms, including fish. In this study, molecular docking and molecular dynamics techniques were employed to evaluate the endocrine-disrupting potential of PAHs in zebrafish, as a model organism. A virtual screening with 72 PAHs revealed a correlation between the number of PAH aromatic rings and their binding affinity to proteins involved in endocrine regulation. Furthermore, PAHs with the highest binding affinities for each protein were identified: cyclopenta[cd]pyrene for AR (-9.7 kcal/mol), benzo(g)chrysene for ERα (-11.5 kcal/mol), dibenzo(a,e)pyrene for SHBG (-8.7 kcal/mol), dibenz(a,h)anthracene for StAR (-11.2 kcal/mol), and 2,3-benzofluorene for TRα (-9.8 kcal/mol). Molecular dynamics simulations confirmed the stability of the protein-ligand complexes formed by the PAHs with the highest binding affinities throughout the simulations. Additionally, the effectiveness of the protocol used in this study was demonstrated by the receiver operating characteristic curve (ROC) analysis, which effectively distinguished decoys from true ligands. Therefore, this research provides valuable insights into the endocrine-disrupting potential of PAHs in fish, highlighting the importance of assessing their impact on aquatic ecosystems.

Biodegradation of bisphenol A by a Pichia pastoris whole-cell biocatalyst with overexpression of laccase from Bacillus pumilus and investigation of its potential degradation pathways.

Bisphenol A (BPA), an endocrine disrupter with estrogen activity, can infiltrate animal and human bodies through the food chain. Enzymatic degradation of BPA holds promise as an environmentally friendly approach while it is limited due to lower stability and recycling challenges. In this study, laccase from Bacillus pumilus TCCC 11568 was expressed in Pichia pastoris (fLAC). The optimal catalytic conditions for fLAC were at pH 6.0 and 80 °C, with a half-life T1/2 of 120 min at 70 °C. fLAC achieved a 46 % degradation rate of BPA, and possible degradation pathways were proposed based on identified products and reported intermediates of BPA degradation. To improve its stability and degradation capacity, a whole-cell biocatalyst (WCB) was developed by displaying LAC (dLAC) on the surface of P. pastoris GS115. The functionally displayed LAC demonstrated enhanced thermostability and pH stability along with an improved BPA degradation ability, achieving a 91 % degradation rate. Additionally, dLAC maintained a degradation rate of over 50 % after the fourth successive cycles. This work provides a powerful catalyst for degrading BPA, which might decontaminate endocrine disruptor-contaminated water through nine possible pathways.

Selective biodegradation of octylphenol polyethoxylates with different ethoxylate length chains by aerobic bacterial culture.

Octylphenol polyethoxylates (OPEOn) are composed of a hydrophobic octylphenol (OP) group and a hydrophilic polyethylene oxide (EO) chain and are widely used in commercial products. Shorter EO chains and OPEOn biometabolites have been identified as endocrine-disrupting contaminants and can threaten biotic factors in the ecosystem. In this study, OPEOn at three EO lengths (TX-45, TX-114, and TX-165) were selected in monomer (MN) or micelle (MC) state for batch experiments under aerobic conditions, with results showing biodegradation rates of 90 % within 35-70 h. The pseudo-first-order constant (k) of OPEOn biodegradation was observed in the order TX-45 (0.1414 h-1) > TX-114 (0.0556 h-1) > TX-165 (0.0485 h-1), with biomineralisation reaching at least 80 % for all OPEOn. The selective biodegradation of EO chains was also measured, with initial accumulation of OPEO3 observed along with the depletion of longer EO chains for TX-45 and TX-114 in both the MN and MC states. A similar trend was observed for the MN state of TX-165, with OPEO3-OPEO9 observed to accumulate and reduced after 70 h. MC biodegradation was accomplished via the initial accumulation of OPEO3-OPEO9. The amounts of OPEO3 increased and others reduced; however, OPEO3 remained high at the end of biodegradation for TX-165. Bacterial community analysis indicated that the genera Sphingobium spp., Pseudomonas spp., Flavobacterium spp., Comamonas spp., and Sphingopyxis spp. dominate OPEOn biodegradation, and they have their roles during biodegradation, and the community-level physiological profile (CLPP) was also changed by biodegradation in both the MN and MC states.

Estrogen-related receptor, a molecular target against lepidoptera pests.

Until recently, chemical pesticides were one of the most effective means of controlling agricultural pests; therefore, the search for insecticide targets for agricultural pests has been an ongoing problem. Estrogen-related receptors (ERRs) are transcription factors that regulate cellular metabolism and energy homeostasis in animals. Silkworms are highly sensitive to chemical pesticides, making them ideal models for pesticide screening and evaluation. In this study, we detected ERR expression in key organs involved in pesticide metabolism in silkworms (Bombyx mori), including the fat body and midgut. Using ChIP-seq technology, many estrogen- related response elements were identified in the 2000-bp promoter region upstream of metabolism-related genes, almost all of which were potential ERR target genes. The ERR inhibitor, XCT-790, and the endocrine disruptor, bisphenol A, significantly inhibited expression of the ERR target genes, BmTreh-1, BmTret-1, BmPK, BmPFK, and BmHK, in the fat bodies of silkworms, resulting in pupation difficulties in silkworm larvae that ultimately lead to death. In addition, based on the clarification that the ERR can bind to XCT-790, as observed through biofilm interferometry, its three-dimensional spatial structure was predicted, and using molecular docking techniques, small-molecule compounds with a stronger affinity for the ERR were identified. In summary, utilizing the powerful metabolic regulatory function of ERR in Lepidoptera pests, the developed small molecule inhibitors of ERR can be used for future control of Lepidoptera pests.

Response surface methodology directed modeling of the biosorption of progesterone onto acid activated Moringa oleifera seed biomass: Parameters and mechanisms.

In this study, chemically activated fat-free powdered Moringa oleifera seed biomass (MOSB) was synthesized, characterized, and utilized as a cost-effective biosorbent for the abstraction of progesterone (PGT) hormone from synthetic wastewater. Natural PGT is a human steroid hormone from the progestogen family. Synthetic PGT is approved for the regulation of the menstrual cycle, aiding contraception, and is administered as a hormone replacement therapy in menopausal and post-menopausal women. PGT is an endocrine disrupting chemical (EDC) with negative health impacts on biota. The X-ray diffractogram (XRD), Scanning electron microscopy-Energy-dispersive X-ray spectroscopy (SEM-EDS), and Brunauer-Emmet-Teller (BET) analyses displayed a porous, amorphous biosorbent with an elemental composition of 72.5% carbon and 22.5% oxygen and a specific surface area of 210.0 m2 g-1. The process variables including temperature (298-338 K), pH (2-10), contact time (10-180 min), adsorbate concentration (20-500 µg L-1), and adsorbent dosage (0.1-2.0 g) were optimized using response surface methodology (RSM) to obtain the greatest efficacy of MOSB during biosorption of PGT. The optimum parameters for PGT biosorption onto MOSB were: 86.8 min, 500 µg L-1 adsorbate concentration, 298 K, and 0.1 g adsorbent dosage. PGT removal from aqueous solutions was pH-independent. The Langmuir isotherm best fitted the equilibrium data with maximal monolayer biosorption capacity of 135.8 µg g-1. The biosorption rate followed the pseudo-first-order (PFO) kinetic law. The thermodynamic functions (ΔG < 0, ΔH = -9.258 kJ mol-1 and ΔS = +44.16 J mol-1) confirmed that the biosorption of PGT onto MOSB is a spontaneous and exothermic process with increased randomness at the adsorbent surface. The biosorption mechanism was physisorption and was devoid of electrostatic interactions. The findings from this study indicate that MOSB is an inexpensive, low-carbon, and environmentally friendly biosorbent that can effectively scavenge PGT from aqueous solutions.

Electrochemical degradation of diclofenac generates unexpected thyroidogenic transformation products: Implications for environmental risk assessment.

Diclofenac (DCF) is an environmentally persistent, nonsteroidal anti-inflammatory drug (NSAID) with thyroid disrupting properties. Electrochemical advanced oxidation processes (eAOPs) can efficiently remove NSAIDs from wastewater. However, eAOPs can generate transformation products (TPs) with unknown chemical and biological characteristics. In this study, DCF was electrochemically degraded using a boron-doped diamond anode. Ultra-high performance liquid chromatography coupled with high-resolution mass spectrometry was used to analyze the TPs of DCF and elucidate its potential degradation pathways. The biological impact of DCF and its TPs was evaluated using the Xenopus Eleutheroembryo Thyroid Assay, employing a transgenic amphibian model to assess thyroid axis activity. As DCF degradation progressed, in vivo thyroid activity transitioned from anti-thyroid in non-treated samples to pro-thyroid in intermediately treated samples, implying the emergence of thyroid-active TPs with distinct modes of action compared to DCF. Molecular docking analysis revealed that certain TPs bind to the thyroid receptor, potentially triggering thyroid hormone-like responses. Moreover, acute toxicity occurred in intermediately degraded samples, indicating the generation of TPs exhibiting higher toxicity than DCF. Both acute toxicity and thyroid effects were mitigated with a prolonged degradation time. This study highlights the importance of integrating in vivo bioassays in the environmental risk assessment of novel degradation processes.

Computational study on the endocrine-disrupting metabolic activation of Benzophenone-3 catalyzed by cytochrome P450 1A1: A QM/MM approach.

Predicting the metabolic activation mechanism and potential hazardous metabolites of environmental endocrine-disruptors is a challenging and significant task in risk assessment. Here the metabolic activation mechanism of benzophenone-3 catalyzed by P450 1A1 was investigated by using Molecular Dynamics, Quantum Mechanics/Molecular Mechanics and Density Functional Theory approaches. Two elementary reactions involved in the metabolic activation of BP-3 with P450 1A1: electrophilic addition and hydrogen abstraction reactions were both discussed. Further conversion reactions of epoxidation products, ketone products and the formaldehyde formation reaction were investigated in the non-enzymatic environment based on previous experimental reports. Binding affinities analysis of benzophenone-3 and its metabolites to sex hormone binding globulin indirectly demonstrates that they all exhibit endocrine-disrupting property. Toxic analysis shows that the eco-toxicity and bioaccumulation values of the benzophenone-3 metabolites are much lower than those of benzophenone-3. However, the metabolites are found to have skin-sensitization effects. The present study provides a deep insight into the biotransformation process of benzophenone-3 catalyzed by P450 1A1 and alerts us to pay attention to the adverse effects of benzophenone-3 and its metabolites in human livers.

Functional analysis, diversity, and distribution of the ean cluster responsible for 17ß-estradiol degradation in sphingomonads.

17ß-estradiol (E2) is a natural endocrine disruptor that is frequently detected in surface and groundwater sources, thereby threatening ecosystems and human health. The newly isolated E2-degrading strain Sphingomonas colocasiae C3-2 can degrade E2 through both the 4,5-seco pathway and the 9,10-seco pathway; the former is the primary pathway supporting the growth of this strain and the latter is a branching pathway. The novel gene cluster ean was found to be responsible for E2 degradation through the 4,5-seco pathway, where E2 is converted to estrone (E1) by EanA, which belongs to the short-chain dehydrogenases/reductases (SDR) superfamily. A three-component oxygenase system (including the P450 monooxygenase EanB1, the small iron-sulfur protein ferredoxin EanB2, and the ferredoxin reductase EanB3) was responsible for hydroxylating E1 to 4-hydroxyestrone (4-OH-E1). The enzymatic assay showed that the proportion of the three components is critical for its function. The dioxygenase EanC catalyzes ring A cleavage of 4-OH-E1, and the oxidoreductase EanD is responsible for the decarboxylation of the ring A-cleavage product of 4-OH-E1. EanR, a TetR family transcriptional regulator, acts as a transcriptional repressor of the ean cluster. The ean cluster was also found in other reported E2-degrading sphingomonads. In addition, the novel two-component monooxygenase EanE1E2 can open ring B of 4-OH-E1 via the 9,10-seco pathway, but its encoding genes are not located within the ean cluster. These results refine research on genes involved in E2 degradation and enrich the understanding of the cleavages of ring A and ring B of E2.IMPORTANCESteroid estrogens have been detected in diverse environments, ranging from oceans and rivers to soils and groundwater, posing serious risks to both human health and ecological safety. The United States National Toxicology Program and the World Health Organization have both classified estrogens as Group 1 carcinogens. Several model organisms (proteobacteria) have established the 4,5-seco pathway for estrogen degradation. In this study, the newly isolated Sphingomonas colocasiae C3-2 could degrade E2 through both the 4,5-seco pathway and the 9,10-seco pathway. The novel gene cluster ean (including eanA, eanB1, eanC, and eanD) responsible for E2 degradation by the 4,5-seco pathway was identified; the novel two-component monooxygenase EanE1E2 can open ring B of 4-OH-E1 through the 9,10-seco pathway. The TetR family transcriptional regulator EanR acts as a transcriptional repressor of the ean cluster. The cluster ean was also found to be present in other reported E2-degrading sphingomonads, indicating the ubiquity of the E2 metabolism in the environment.

Microbial synergies drive simultaneous biodegradation of ethoxy and alkyl chains of Nonylphenol Ethoxylate in fluidized bed reactors.

The widely-used surfactant Nonylphenol Ethoxylate (NPEO) produces endocrine-disrupting compounds during biodegradation, with these byproducts being more harmful than untreated NPEO. This study investigates the effectiveness of a Fluidized Bed Reactor (FBR) in reducing the production of 4-Nonylphenol (4-NP) during the biodegradation of NPEO. Two identical FBR filled with sand were used to assess the NPEO degradation and to enhance the microbial consortia capable of breaking down the complex byproducts, ethanol and fumarate were introduced as co-substrates. Our findings demonstrate the significant potential of the FBR, especially when coupled with fumarate, for enhancing the surfactant degradation. It outperforms the efficiency achieved with ethanol as the primary electron donor, albeit with a higher rate of byproduct production. Microbial community taxonomy and metabolic prediction revealed the high abundance of Geobacter (1.51-31.71%) and Methanobacterium (1.08-13.81%) in non-conductive sand. This may hint a new metabolic interaction and expand our understanding of Direct Interspecies Electron Transfer (DIET) in bioreactors applied to micropollutants degradation. Such an intricate relationship between facultative and anaerobes working together to simultaneously biodegrade the ethoxy and alkyl chains presents a new perspective on NPEO degradation and can potentially be extended to other micropollutants.

Gender-specific abdominal fat distribution and insulin resistance associated with organophosphate esters and phthalate metabolites exposure.

The worldwide prevalence of obesity highlights the potential contribution of endocrine-disrupting chemicals (EDCs). However, common epidemiological measures such as body mass index and waist circumference may misrepresent the intricate obesity risks these chemicals pose across genders. This study delves deeper into abdominal fat by differentiating between subcutaneous and visceral regions by analyzing data from National Health and Nutrition Examination Surveys (NHANES). We particularly investigated the gender-specific associations between organophosphorus flame-retardant metabolites (mOPFRs), phthalates (mPAEs) and accumulated fat indexes from 2536 people. Aiding by Bayesian Kernel Machine Regression (BKMR), we found while co-exposure to mOPFRs and mPAEs was linked to general and abdominal obesity across the entire and gender-specific populations, a gender-specific fat distribution emerged. For women, urinary BDCPP and MBzP were linked to an increased subcutaneous fat index (SFI) [BDCPP OR: 1.12 (95% CI: 1.03-1.21), MBzP OR: 1.09 (95% CI: 1.01-1.18)], but not to visceral fat index (VFI). These metabolites had a combined linkage with SFI, with BDCPP (weighting 22.0%) and DPHP (weighting 31.0%) being the most influential in Quantile g-computation model (qgcomp) model. In men, BCEP exposure exclusively associated with the elevated VFI [OR: 1.14 (95% CI: 1.03-1.26)], a trend further highlighted in mixture models with BCEP as the predominant association. Intriguingly, only males displayed a marked correlation between these metabolites and insulin resistance in subpopulation. An attempted mediation analysis revealed that elevated C-reactive protein mediated 12.1% of the association between urinary BCEP and insulin resistance, suggesting a potential role of inflammation. In conclusion, the gender-specific fat distribution and insulin resistance that associated with mOPFRs represented the potential risk of these chemicals to man.

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.

Chlorothalonil as a potential endocrine disruptor in male zebrafish (Danio rerio): Impact on the hypothalamus-pituitary-gonad axis and sperm quality.

Chlorothalonil is a broad-spectrum organochlorine fungicide widely employed in agriculture to control fungal foliar diseases. This fungicide enters aquatic environments through the leaching process, leading to toxicity in non-target organisms. Organic contaminants can impact organism reproduction as they have the potential to interact with the neuroendocrine system. Although there are reports of toxic effects of chlorothalonil, information regarding its impact on reproduction is limited. The aim of the present study was to evaluate the influence of chlorothalonil on male reproductive physiology using the zebrafish (Danio rerio) as ecotoxicological model. Zebrafish were exposed for 7 days to two concentrations of chlorothalonil (0.1 and 10 µg/L) along with a control group (with DMSO - 0.001%). Gene expression of hypothalamus-pituitary-gonad axis components (gnrh2, gnrh3, lhr, fshr, star, hsd17b1, hsd17b3, and cyp19a1), as well as hepatic vitellogenin concentration were assessed. In sperm cells, reactive oxygen species (ROS) content, lipid peroxidation (LPO), mitochondrial functionality, and membrane integrity and fluidity were evaluated. Results indicate that exposure to the higher concentration of chlorothalonil led to a reduction in brain gnr2 expression. In gonads, mRNA levels of lhr, star, and hsd17b1 were decreased at both chlorothalonil concentrations tested. Similarly, hepatic vitellogenin concentration was reduced. Regarding sperm cells, a decreased ROS level was observed, without significant difference in LPO level. Additionally, a higher mitochondrial potential and lower membrane fluidity were observed in zebrafish exposed to chlorothalonil. These findings demonstrate that chlorothalonil acts as an endocrine disruptor, influencing reproductive control mechanisms, as evidenced by changes in expression of genes HPG axis, as well as hepatic vitellogenin concentration. Furthermore, our findings reveal that exposure to this contaminant may compromise the reproductive success of the species, as it affected sperm quality parameters.

Prediction of the Interactions of a Large Number of Per- and Poly-Fluoroalkyl Substances with Ten Nuclear Receptors.

Per- and poly-fluoroalkyl substances (PFASs) are persistent, toxic chemicals that pose significant hazards to human health and the environment. Screening large numbers of chemicals for their ability to act as endocrine disruptors by modulating the activity of nuclear receptors (NRs) is challenging because of the time and cost of in vitro and in vivo experiments. For this reason, we need computational approaches to screen these chemicals and quickly prioritize them for further testing. Here, we utilized molecular modeling and machine-learning predictions to identify potential interactions between 4545 PFASs with ten different NRs. The results show that some PFASs can bind strongly to several receptors. Further, PFASs that bind to different receptors can have very different structures spread throughout the chemical space. Biological validation of these in silico findings should be a high priority.

Environmental bisphenol A disrupts methylation of steroidogenic genes in the ovary of Paradise threadfin Polynemus paradiseus via abnormal DNA methylation: Implications for human exposure and health risk assessment.

Bisphenol A, endocrine-disrupting chemicals (EDCs) impacting disease development via epigenetic modifications, is crucial in transcriptional regulation. However, ecotoxicology's limited exploration of epigenetics prompted our study's objective: examining the extended exposure of riverine Bisphenol A (BPA), a potent EDC, on DNA methylation during female paradise threadfin (Polynemus paradiseus) reproductive maturation. Assessing BPA contamination in riverine water, we collected fish samples from two locations with distinct contamination levels. In the highly contaminated region (Hc), we observed elevated DNA methylation in aromatase (7.5-fold), 20ß-HSD (3-fold), and FSHR (2-fold) genes. Hormone receptor investigation highlighted an escalating connection between transcriptional hyper-methylation and contamination levels. Additionally, our study revealed a positive correlation between oocyte growth and global DNA methylation, suggesting BPA's potential to modify DNA methylation in female paradise threadfins. This effect likely occurs through changes in hormone receptor expression, persisting throughout oocyte maturation. Notably, our research, the first of its kind in estuarine areas, confirmed BPA contamination in paradise threadfins, raising concerns about potential health risks for humans.

Bioaccumulation and thyroid endcrione disruption of 2-ethylhexyl diphenyl phosphate at environmental concentration in zebrafish larvae.

2-ethylhexyl diphenyl phosphate (EHDPP) strongly binds to transthyretin (TTR) and affects the expression of genes involved in the thyroid hormone (TH) pathway in vitro. However, it is still unknown whether EHDPP induces endocrine disruption of THs in vivo. In this study, zebrafish (Danio rerio) embryos (< 2 h post-fertilization (hpf)) were exposed to environmentally relevant concentrations of EHDPP (0, 0.1, 1, 10, and 100 µg·L-1) for 120 h. EHDPP was detected in 120 hpf larvae at concentrations of 0.06, 0.15, 3.71, and 59.77 µg·g-1 dry weight in the 0.1, 1, 10, and 100 µg·L-1 exposure groups, respectively. Zebrafish development and growth were inhibited by EHDPP, as indicated by the increased malformation rate, decreased survival rate, and shortened body length. Exposure to lower concentrations of EHDPP (0.1 and 1 µg·L-1) significantly decreased the whole-body thyroxine (T4) and triiodothyronine (T3) levels and altered the expressions of genes and proteins involved in the hypothalamic-pituitary-thyroid axis. Downregulation of genes related to TH synthesis (nis and tg) and TH metabolism (dio1 and dio2) may be partially responsible for the decreased T4 and T3 levels, respectively. EHDPP exposure also significantly increased the transcription of genes involved in thyroid development (nkx2.1 and pax8), which may stimulate the growth of thyroid primordium to compensate for hypothyroidism. Moreover, EHDPP exposure significantly decreased the gene and protein expression of the transport protein transthyretin (TTR) in a concentration-dependent manner, suggesting a significant inhibitory effect of EHDPP on TTR. Molecular docking results showed that EHDPP and T4 partly share the same mode of action of binding to the TTR protein, which might result in decreased T4 transport due to the binding of EHDPP to the TTR protein. Taken together, our findings indicate that EHDPP can cause TH disruption in zebrafish and help elucidate the mechanisms underlying EHDPP toxicity.

Assessment of endocrine disruptor impacts on lipid metabolism in a fatty acid-supplemented HepaRG human hepatic cell line.

The incidence of metabolic dysfunction-associated steatotic liver disease (MASLD) is increasing worldwide. This disease encompasses several stages, from steatosis to steatohepatitis and, eventually, to fibrosis and cirrhosis. Exposure to environmental contaminants is one of the risk factors and an increasing amount of evidence points to a role for endocrine disrupting compounds (EDCs). This study assesses the impact of selected EDCs on the formation of lipid droplets, the marker for steatosis in a hepatic model. The mechanisms underlying this effect are then explored. Ten compounds were selected according to their obesogenic properties: bisphenol A, F and S, butyl-paraben, cadmium chloride, p,p'-DDE, DBP, DEHP, PFOA and PFOS. Using a 2D or 3D model, HepaRG cells were exposed to the compounds with or without fatty acid supplementation. Then, the formation of lipid droplets was quantified by an automated fluorescence-based method. The expression of genes and proteins involved in lipid metabolism and the impact on cellular respiration was analyzed. The formation of lipid droplets, which is revealed or enhanced by oleic acid supplementation, was most effectively induced by p,p'-DDE and DEHP. Experiments employing either 2D or 3D culture conditions gave similar results. Both compounds induced the expression of PLIN2. p,p'-DDE also appears to act by decreasing in fatty acid oxidation. Some EDCs were able to induce the formation of lipid droplets, in HepaRG cells, an effect which was increased after supplementation of the cells with oleic acid. A full understanding of the mechanisms of these effects will require further investigation. The novel automated detection method described here may also be useful in the future as a regulatory test for EDC risk assessment.

Systematic transcriptome-wide meta-analysis across endocrine disrupting chemicals reveals shared and unique liver pathways, gene networks, and disease associations.

Cardiometabolic disorders (CMD) are a growing public health problem across the world. Among the known cardiometabolic risk factors are compounds that induce endocrine and metabolic dysfunctions, such as endocrine disrupting chemicals (EDCs). To date, how EDCs influence molecular programs and cardiometabolic risks has yet to be fully elucidated, especially considering the complexity contributed by species-, chemical-, and dose-specific effects. Moreover, different experimental and analytical methodologies employed by different studies pose challenges when comparing findings across studies. To explore the molecular mechanisms of EDCs in a systematic manner, we established a data-driven computational approach to meta-analyze 30 human, mouse, and rat liver transcriptomic datasets for 4 EDCs, namely bisphenol A (BPA), bis(2-ethylhexyl) phthalate (DEHP), tributyltin (TBT), and perfluorooctanoic acid (PFOA). Our computational pipeline uniformly re-analyzed pre-processed quality-controlled microarray data and raw RNAseq data, derived differentially expressed genes (DEGs) and biological pathways, modeled gene regulatory networks and regulators, and determined CMD associations based on gene overlap analysis. Our approach revealed that DEHP and PFOA shared stable transcriptomic signatures that are enriched for genes associated with CMDs, suggesting similar mechanisms of action such as perturbations of peroxisome proliferator-activated receptor gamma (PPARγ) signaling and liver gene network regulators VNN1 and ACOT2. In contrast, TBT exhibited highly divergent gene signatures, pathways, network regulators, and disease associations from the other EDCs. In addition, we found that the rat, mouse, and human BPA studies showed highly variable transcriptomic patterns, providing molecular support for the variability in BPA responses. Our work offers insights into the commonality and differences in the molecular mechanisms of various EDCs and establishes a streamlined data-driven workflow to compare molecular mechanisms of environmental substances to elucidate the underlying connections between chemical exposure and disease risks.

In vivo and in silico toxicity assessment of four common liquid crystal monomers to Daphnia magna: Novel endocrine disrupting chemicals in crustaceans?

Liquid crystal monomers (LCMs) are widely used in liquid crystal displays (LCDs) and are proposed to be a new generation of environmentally persistent, bioaccumulative and toxic (PBT) substances that are increasingly detected in rivers and seas. However, there is a lack of in vivo data that characterize adverse responses and toxic mechanisms of LCMs on aquatic organisms. The aim of this study was to comprehensively investigate the effect of four typical LCMs on the lethality, growth, molting, and reproductive capacity of Daphnia magna (D. magna), a highly studied aquatic species in environmental toxicology. Whole body and enzymatic biomarkers (i.e., body length, chitobiase, acetylcholinesterase, antioxidant defense) were measured to assess the toxicity of LCMs. The 48 h mortality rate and observations of disrupted thorax development and inhibition of ecdysis indicate that D. magna are sensitive to LCMs exposure. Oxidative stress, impaired neurotransmission, and disruptions in molting were observed in short-term biomarker tests using LCMs. A 21 day exposure of D. magna to LCMs resulted in reduced growth, reproduction, and population intrinsic growth rate. In addition, chitobiase and 20-hydroxyecdysone, enzymes important for the molting process, were altered at 7, 14 and 21 d. This is hypothesized to be related to endocrine imbalance resulting from LCM exposure. Based on molecular docking simulations, there is evidence that LCMs bind directly to ecdysteroid receptors; this may explain the observed endocrine disrupting effects of LCMs. These data support the hypothesis that LCMs are endocrine disrupting chemicals in aquatic species, impacting the process of molting. This may subsequently lead to lower reproduction and unbalanced population dynamics.

Pharmaceuticals and endocrine disrupting compounds modulate adverse effects of climate change on resource quality in freshwater food webs.

Freshwater biodiversity, ecosystem functions and services are changing at an unprecedented rate due to the impacts of vast number of stressors overlapping in time and space. Our study aimed at characterizing individual and combined impacts of pollution with pharmaceuticals (PhACs) and endocrine disrupting compounds (EDCs) and increased water temperature (as a proxy for climate change) on primary producers and first level consumers in freshwaters. We conducted a microcosm experiment with a simplified freshwater food web containing moss (Bryophyta) and shredding caddisfly larvae of Micropterna nycterobia (Trichoptera). The experiment was conducted with four treatments; control (C), increased water temperature + 4 °C (T2), emerging contaminants' mix (EC = 15 PhACs & 5 EDCs), and multiple stressor treatment (MS = EC + T2). Moss exhibited an overall mild response to selected stressors and their combination. Higher water temperature negatively affected development of M. nycterobia through causing earlier emergence of adults and changes in their lipidome profiles. Pollution with PhACs and EDCs had higher impact on metabolism of all life stages of M. nycterobia than warming. Multiple stressor effect was recorded in M. nycterobia adults in metabolic response, lipidome profiles and as a decrease in total lipid content. Sex specific response to stressor effects was observed in adults, with impacts on metabolome generally more pronounced in females, and on lipidome in males. Thus, our study highlights the variability of both single and multiple stressor impacts on different traits, different life stages and sexes of a single insect species. Furthermore, our research suggests that the combined impacts of warming, linked to climate change, and contamination with PhACs and EDCs could have adverse consequences on the population dynamics of aquatic insects. Additionally, these findings point to a potential decrease in the quality of resources available for both aquatic and potentially terrestrial food webs.

Ovarian follicular fluid levels of phthalates and benzophenones in relation to fertility outcomes.

BACKGROUND: Many endocrine disrupting chemicals (EDCs), for instance phthalates and benzophenones, are associated with adverse fertility outcomes and semen quality parameters. OBJECTIVE: To evaluate if concentrations of selected phthalate metabolites and benzophenones measured in follicular fluid are associated with fertility outcomes (i.e., reproductive hormones, antral follicle count, detected heartbeat at gestational week 7, and live birth) and, in a supplementary study, if measured concentrations of chemicals in follicular fluid can exert biological effects on human spermatozoa. METHODS: Overall, 111 couples from a fertility clinic in Denmark contributed with 155 follicular fluid samples. Concentrations of 43 metabolites from 19 phthalates and phthalate substitutes and six benzophenones were measured in follicular fluid using liquid chromatography-tandem mass spectrometry. Multiple linear and logistic regression with an applied generalized estimating equation model allowing more than one measurement per woman assessed the association between follicular EDC levels and fertility outcomes. The assessment of biological effects of individual and mixtures of EDCs on human spermatozoa was conducted through a human sperm cell based Ca2+-fluorimetric assay. RESULTS: Benzophenone-3 (BP-3) and seven metabolites of five phthalates were detectable in follicular fluid. Women with metabolites of dibutyl phthalate isomers in the highest tertiles had lower antral follicle count (MiBP: ß = -5.35 [95 % CI: -9.06; -2.00], MnBP: ß = -5.25 [95 % CI: -9.00; -2.00]) and lower odds for detecting a heartbeat at gestational week 7 (MiBP: OR = 0.35 [95 % CI: 0.14; 0.91], MnBP: OR = 0.39 [95 % CI: 0.13; 1.15]). Mixtures of the measured concentrations of BP-3 and the seven phthalate metabolites induced a small significant increase in the intracellular calcium ion concentration in human spermatozoa from healthy donors (n = 3). DISCUSSION: Phthalate metabolites and BP-3 were detectable in follicular fluid and high concentrations of some phthalate metabolites were linked with lower chance of successful fertility treatment outcomes. Chemical mixture concentrations in follicular fluid induced a calcium response in human spermatozoa highlighting possible biological effects at physiologically relevant concentrations.