Spermatogenesis starts with the onset of puberty within the seminiferous epithelium of the testes. It is a complex process under intricate control of the endocrine system. Physiological regulations by steroid hormones in general and by estrogens in particular are due to their chemical nature prone to be disrupted by exogenous factors acting as endocrine disruptors (EDs). 17α-Ethynylestradiol (EE2) is an environmental pollutant with a confirmed ED activity and a well-known effect on spermatogenesis and chromatin remodeling in haploid germ cells. The aim of our study was to assess possible effects of two doses (2.5ng/ml; 2.5 μg/ml) of EE2 on both histone-to-protamine exchange and epigenetic profiles during spermatogenesis performing a multi/transgenerational study in mice. Our results demonstrated an impaired histone-to-protamine exchange with a significantly higher histone retention in sperm nuclei of exposed animals, when this process was accompanied by the changes of histone post-translational modifications (PTMs) abundancies with a prominent effect on H3K9Ac and partial changes in protamine 1 promoter methylation status. Furthermore, individual changes in molecular phenotypes were partially transmitted to subsequent generations, when no direct trans-generational effect was observed. Finally, the uncovered specific localization of the histone retention in sperm nuclei and their specific PTMs profile after EE2 exposure may indicate an estrogenic effect on sperm motility and early embryonic development via epigenetic mechanisms.
- MeSH
- Endocrine Disruptors pharmacology toxicity MeSH
- Epigenesis, Genetic * drug effects MeSH
- Ethinyl Estradiol * pharmacology MeSH
- Histones * metabolism MeSH
- Mice MeSH
- Protein Processing, Post-Translational drug effects MeSH
- Protamines * metabolism genetics MeSH
- Spermatogenesis * drug effects genetics MeSH
- Spermatozoa drug effects metabolism MeSH
- Testis * drug effects metabolism MeSH
- Animals MeSH
- Check Tag
- Male MeSH
- Mice MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
The oestrogen receptor (ER) from the nuclear receptor family is involved in different physiological processes, which can be affected by multiple xenobiotics. Some of these compounds, such as bisphenols, pesticides, and phthalates, are widespread as consequence of human activities and are commonly present also in human organism. Xenobiotics able to interact with ER and trigger a hormone-like response, are known as endocrine disruptors. In this review, we aim to summarize the available knowledge on products derived from human industrial activity and other xenobiotics reported to interact with ER. ER-disrupting chemicals behave differently towards oestrogen-dependent cell lines than endogenous oestradiol. In low concentrations, they stimulate proliferation, whereas at higher concentrations, are toxic to cells. In addition, most of the knowledge on the topic is based on individual compound testing, and only a few studies assess xenobiotic combinations, which better resemble real circumstances. Confirmation from in vivo models is lacking also.
- MeSH
- Endocrine Disruptors * toxicity MeSH
- Estradiol MeSH
- Estrogens toxicity MeSH
- Humans MeSH
- Receptors, Estrogen * metabolism MeSH
- Xenobiotics toxicity MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
Endocrine disruptors (EDs) are ubiquitous substances both in the environment and everyday products that interfere with the hormonal system. Growing evidence demonstrates their adverse effects on the organism, including the reproductive system and the prostate, owing to their (anti)estrogenic or antiandrogenic effects. Since EDs can interact with steroid hormone actions on-site, understanding the levels of intraprostatic EDs in conjunction with steroids may hold particular significance. The aim of this study was to develop and validate a method for determining estrogens, various groups of EDs (bisphenols, parabens, oxybenzone and nonylphenol) and phytoestrogens in their unconjugated and conjugated forms in prostate tissue by liquid chromatography-tandem mass spectrometry, and subsequently analyze 20 human prostate tissue samples. The method enabled 20 compounds to be analyzed: estrogens (estrone, estradiol, estriol), bisphenols (bisphenol A- BPA, BPS, BPF, BPAF, BPAP, BPZ, BPP), parabens (methyl-, ethyl-, propyl-, butyl-, benzyl- paraben), oxybenzone, nonylphenol and phytoestrogens (daidzein, genistein, equol) with LLOQs between 0.017-2.86 pg/mg of tissue. The most frequently detected EDs in prostate tissues were propylparaben (conjugated and unconjugated forms in 100 % of tissues), methylparaben (unconjugated in 45 % and conjugated in 100 %), ethylparaben (unconjugated in 25 % and conjugated in 100 % BPA (unconjugated in 35 % and conjugated in 60 % and oxybenzone (both forms in 45 % To the best of our knowledge, this is the first study detecting EDs, phytoestrogens and estriol conjugate (E3C) in the prostate. E3C was the most abundant estrogen in prostatic tissue. This highlights the need for further explorations into estrogen metabolism within the prostate.
- MeSH
- Benzhydryl Compounds MeSH
- Endocrine Disruptors * MeSH
- Estriol MeSH
- Estrogens * MeSH
- Phytoestrogens MeSH
- Humans MeSH
- Parabens MeSH
- Prostate chemistry MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Publication type
- Journal Article MeSH
Cell-based bioassays are very sensitive and allow integrative effect screening of the whole environmental sample, which is usually composed of a mixture of agonists and antagonists. Measured toxicity is usually expressed as a bioanalytical equivalent concentration. So far, it is not possible to distinguish which part of this value is caused by the agonists and which by the antagonists. In this article, we present a simple method to analyze the dose-response curve of a mixture and to determine an agonistic bioanalytical equivalent concentration: a concentration of a reference chemical that would elicit the same effect as do only agonists in an unknown mixture. The method has been validated using several artificially prepared mixtures of agonists and competitive antagonists measured in a recombinant yeast assay. No difference was observed between the calculated equivalent concentrations and the used concentrations of the agonist in the mixture.
- MeSH
- Biological Assay methods MeSH
- Endocrine Disruptors * MeSH
- Estradiol pharmacology MeSH
- Estriol pharmacology MeSH
- Fulvestrant pharmacology MeSH
- Environmental Pollutants toxicity MeSH
- Drug Interactions MeSH
- Receptors, Estrogen antagonists & inhibitors MeSH
- Saccharomyces cerevisiae drug effects MeSH
- Models, Theoretical MeSH
- Publication type
- Journal Article MeSH
Theoretical basis: The menopause is a period in women’s lives when their ability to reproduce decreases, and as it gradually ends, women move into the so-called post-production phase. In this transitional phase, women are at risk of developing various symptoms, which are affected by more factors than only a deficiency of ovarian hormones (estrogens). Many recent international studies have shown the influence of other factors on women‘s health during this period, such as the family environment, interpersonal relationships, employment, and ethnic and cultural aspects. Goal: The literature review is devoted to the research of published studies dealing with the influence of ethnicity and culture on the occurrence of symptoms and health of women in the post-reproductive phase of their lives. Methods: We searched for the included studies using the method of content analysis. The scientific databases focused on women’s health, and studies published between 2017 and 2022 were found in databases such as PubMed, Scopus, ScienceDirect, and EBSCO. We used the keywords “ethnicity”, “menopause”, “symptom”, “influence”, “woman”, and the Boolean operator “AND”. The content analysis took place from January to February 2022. After checking the eligibility and relevance of studies, we included and analysed eight articles. Results: It is clear from the literature review results that ethnic and cultural factors are involved in vasomotor, somatic, and cognitive symptoms in women with estrogen deficiency. Conclusions: The information obtained can be helpful, and used in providing individual holistic care to women of different ethnicities in both primary care and inpatient health facilities.
Epigenetic modifications are inherited differences in cellular phenotypes, such as cell gene expression alterations, that occur during somatic cell divisions (also, in rare circumstances, in germ line transmission), but no alterations to the DNA sequence are involved. Histone alterations, polycomb/trithorax associated proteins, short non-coding or short RNAs, long non-coding RNAs (lncRNAs), & DNA methylation are just a few biological processes involved in epigenetic events. These various modifications are intricately linked. The transcriptional potential of genes is closely conditioned by epigenetic control, which is crucial in normal growth and development. Epigenetic mechanisms transmit genomic adaptation to an environment, resulting in a specific phenotype. The purpose of this systematic review is to glance at the roles of Estrogen signalling, polycomb/trithorax associated proteins, DNA methylation in breast cancer progression, as well as epigenetic mechanisms in breast cancer therapy, with an emphasis on functionality, regulatory factors, therapeutic value, and future challenges.
- Publication type
- Journal Article MeSH
- Review MeSH
Mixture toxicity, including agonistic and antagonistic effects, is an unrevealed environmental problem. Estrogenic endocrine disruptors are known to cause adverse effects for aquatic biota, but causative chemicals and their contributions to the total activity in sewage sludge remain unknown. Therefore, advanced analytical methods, a yeast bioassay and mixture toxicity models were concurrently applied for the characterization of 8 selected sludges with delectable estrogenic activity (and 3 sludges with no activity as blanks) out of 25 samples from wastewater treatment plants (WWTPs). The first applied full logistic model adequately explained total activity by considering the concentrations of the monitored compounds. The results showed that the activity was primarily caused by natural estrogens in municipal WWTP sludge. Nevertheless, activity in a sample originating from a car-wash facility was dominantly caused by partial agonists - nonylphenols - and only a model enabling prediction of all dose-response curve parameters of the final mixture curve explained these results. Antiestrogenic effects were negligible, and effect-directed analysis identified the causative chemicals.
Aquatic biotests are important tools targeting various effects in ecotoxicology, including endocrine disruption. Unintentional exposure of bioassay organisms to endocrine disruptors during cultivation or testing may interfere with assessed endpoints. We illustrate this issue on the example of laboratory phytoplankton cultivation, where possible sources of estrogenic compounds have been revealed. Fifty-four blank samples (water and fresh or cultivated growth media) were assessed by in vitro biotests for their estrogenicity, and major known estrogens originating from plastic materials, bisphenol A and alkylphenols, were analyzed in selected samples. The samples of freshly prepared growth medium elicited weak estrogenic response in bioassays and some samples of the aerated media caused responses even above the 50% of maximum of the reference compound (17β-estradiol, E2), while the samples from diverse laboratory water sources did not show significant estrogenic activity. The results identified substances contained in the growth medium as minor but reproducible contributors to estrogenicity in the cultivations. Sporadic but significant effects (up to 4.9 ng E2 equivalent/L) can be ascribed to compounds released from the used plastic materials during aeration of the cultivations. The potential sources of unintentional exposure to estrogenic compounds need to be considered in aquatic cultivations and biotests, since they could impact their outcomes, especially in arrangements assessing reproduction or whole life cycle biotests, or production of bioactive compounds by phytoplankton. The findings emphasize the necessity to assess all relevant blanks, ideally by sensitive high throughput in vitro assays that reflect also unknown pollutants and minimize all potential sources of background contamination. In vitro assays show very good applicability for this purpose since they enable to screen for any background estrogenicity of the used media and materials without the need of analyzing individual compounds, which often might not be known.
Obesity is a chronic, relapsing condition characterized by excess body fat. Its prevalence has increased globally since the 1970s, and the number of obese and overweight people is now greater than those underweight. Obesity is a multifactorial condition, and as such, many components contribute to its development and pathogenesis. This is the first of three companion reviews that consider obesity. This review focuses on the genetics, viruses, insulin resistance, inflammation, gut microbiome, and circadian rhythms that promote obesity, along with hormones, growth factors, and organs and tissues that control its development. It shows that the regulation of energy balance (intake vs. expenditure) relies on the interplay of a variety of hormones from adipose tissue, gastrointestinal tract, pancreas, liver, and brain. It details how integrating central neurotransmitters and peripheral metabolic signals (e.g., leptin, insulin, ghrelin, peptide YY3-36) is essential for controlling energy homeostasis and feeding behavior. It describes the distinct types of adipocytes and how fat cell development is controlled by hormones and growth factors acting via a variety of receptors, including peroxisome proliferator-activated receptor-gamma, retinoid X, insulin, estrogen, androgen, glucocorticoid, thyroid hormone, liver X, constitutive androstane, pregnane X, farnesoid, and aryl hydrocarbon receptors. Finally, it demonstrates that obesity likely has origins in utero. Understanding these biochemical drivers of adiposity and metabolic dysfunction throughout the life cycle lends plausibility and credence to the "obesogen hypothesis" (i.e., the importance of environmental chemicals that disrupt these receptors to promote adiposity or alter metabolism), elucidated more fully in the two companion reviews.
- MeSH
- Energy Metabolism physiology MeSH
- Insulin metabolism MeSH
- Leptin * metabolism MeSH
- Humans MeSH
- Obesity * metabolism MeSH
- Adipose Tissue metabolism MeSH
- Adipocytes metabolism MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
- Research Support, N.I.H., Extramural MeSH
In comparison with analytical tools, bioassays provide higher sensitivity and more complex evaluation of environmental samples and are indispensable tools for monitoring increasing in anthropogenic pollution. Nevertheless, the disadvantage in cellular assays stems from the material variability used within the assays, and an interlaboratory adaptation does not usually lead to satisfactory test sensitivities. The aim of this study was to evaluate the influence of material variability on CXCL12 secretion by T47D cells, the outcome of the CXCL-test (estrogenic activity assay). For this purpose, the cell line sources, sera suppliers, experimental and seeding media, and the amount of cell/well were tested. The multivariable linear model (MLM), employed as an innovative approach in this field for parameter evaluation, identified that all the tested parameters had significant effects. Knowledge of the contributions of each parameter has permitted step-by-step optimization. The most beneficial approach was seeding 20,000 cells/well directly in treatment medium and using DMEM for the treatment. Great differences in both basal and maximal cytokine secretions among the three tested cell lines and different impacts of each serum were also observed. Altogether, both these biologically based and highly variable inputs were additionally assessed by MLM and a subsequent two-step evaluation, which revealed a lower variability and satisfactory reproducibility of the test. This analysis showed that not only parameter and procedure optimization but also the evaluation methodology must be considered from the perspective of interlaboratory method adaptation. This overall methodology could be applied to all bioanalytical methods for fast multiparameter and accurate analysis.