The aim of the study was to examine the potential impacts of bisphenol A (BPA) and its analogues BPB, BPF, and BPS on mice TM3 Leydig cells, with respect to basal cell viability parameters such as metabolic activity, cell membrane integrity, and lysosomal activity after 48-h exposure. In addition, monitoring of potential bisphenol´s actions included evaluation of ROS production and gap junctional intercellular communication (GJIC) complemented by determination of testosterone secretion. Obtained results revealed significant inhibition in mitochondrial activity started at 10 microg/ml of bisphenols after 48-h exposure. Cell membrane integrity was significantly decreased at 5 microg/ml of BPA and BPF and 10, 25, and 50 microg/ml of BPA and BPS. The lysosomal activity was significantly affected at 10, 25, and 50 microg/ml of applied bisphenols. A significant overproduction of ROS was recorded mainly at 5 and 10 microg/ml of tested compounds. In addition, significant inhibition of GJIC was observed at 5 microg/ml of BPB followed by a progressive decline at higher applied doses. In the case of testosterone production, a significant decline was confirmed at 10, 25 and 50 microg/ml.

• MeSH
• benzhydrylové sloučeniny metabolismus   MeSH
• endokrinní disruptory * farmakologie   MeSH
• Leydigovy buňky * MeSH
• myši MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• sulfony farmakologie   MeSH
• testosteron metabolismus   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• benzhydrylové sloučeniny MeSH
• bisphenol A MeSH Prohlížeč
• endokrinní disruptory * MeSH
• reaktivní formy kyslíku MeSH
• sulfony MeSH
• testosteron MeSH

The human population is regularly exposed to bisphenols. The first compound of this class, bisphenol A, is burdened by numerous reports of its potential toxicity and has been hence replaced by its analogues, so-called next generation bisphenols. Their widespread use has made them pervasive throughout the environment. These endocrine disrupting chemicals can affect the cardiovascular system, and hence the aim of this study was to test 14 bisphenols (A, AF, AP, B, BP, C, E, F, G, M, P, PH, S and Z), and compare their effects in vitro (human and rat cell lines), ex vivo (isolated rat aorta) and in vivo (Wistar Han rats, acutely or chronically exposed to low environmental and high toxic doses). The majority of the tested bisphenols relaxed rat aorta, but their potency varied markedly. The most potent compound, bisphenol AF, had an EC50 of 57 μM. The mechanism of action was likely based on the inhibition of calcium influx via L-type calcium channels. The cytotoxicity of bisphenols towards 4 human and rat cell lines (H9c2, A-10, MCF7/S0.5 and MCF7/182R-6) showed variable potencies ranging from units of micromolar to millimolar concentrations. Based on these data, an effect on arterial blood pressure and possible cardiotoxicity was expected. Contrarily, the in vivo acute effects of three doses (0.005, 0.05 and 2.5 mg/kg) of bisphenol AF and 3 other analogues (A, S and F) on the cardiovascular system were rather biologically negligible. The most potent bisphenol, AF, was also administered chronically at a dose of 2.5 mg/kg for 4 weeks to rats, but had no impact on arterial blood pressure. Our results showed that bisphenols can relax vascular smooth muscles, but the effective concentrations are too high to produce clear cardiovascular effects in relation to common biological exposure as was confirmed with the most potent bisphenol AF.

• Klíčová slova
• Bisphenol, Blood pressure, Cardiovascular, Cytotoxicity, Vasorelaxation,
• MeSH
• benzhydrylové sloučeniny * toxicita   metabolismus   MeSH
• kardiovaskulární systém * MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• potkani Wistar MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• 4,4'-hexafluorisopropylidene diphenol MeSH Prohlížeč
• benzhydrylové sloučeniny * MeSH
• bisphenol A MeSH Prohlížeč

There is increasing evidence that bisphenols BPS and BPF, which are analogues of BPA, have deleterious effects on reproduction even at extremely low doses. Indirect exposure via the maternal route (i.e. across the placenta and/or by breastfeeding) is underestimated, although it can be assumed to be a cause of idiopathic female infertility. Therefore, we hypothesised the deleterious effects of exposure to BPA analogues during breastfeeding on the ovarian and oocyte quality of offspring. A 15-day exposure period of pups was designed, whilst nursing dams (N ≥ 6 per experimental group) were treated via drinking water with a low (0.2 ng/g body weight/day) or moderate (20 ng/g body weight/day) dose of bisphenol, mimicking real exposure in humans. Thereafter, female pups were bred to 60 days and oocytes were collected. Immature oocytes were used in the in-vitro maturation assay; alternatively, in-vivo-matured oocytes were isolated and used for parthenogenetic activation. Both in-vitro- and in-vivo-matured oocytes were subjected to immunostaining of spindle microtubules (α-tubulin) and demethylation of histone H3 on the lysine K27 (H3K27me2) residue. Although very low doses of both BPS and BPF did not affect the quality of ovarian histology, spindle formation and epigenetic signs were affected. Notably, in-vitro-matured oocytes were significantly sensitive to both doses of BPS and BPF. Although no significant differences in spindle-chromatin quality were identified in ovulated and in-vivo-matured oocytes, developmental competence was significantly damaged. Taken together, our mouse model provides evidence that bisphenol analogues represent a risk to human reproduction, possibly leading to idiopathic infertility in women.

• Klíčová slova
• Bisphenol, Epigenetics, Oocyte maturation, Spindle formation,
• MeSH
• aparát dělícího vřeténka účinky léků   metabolismus   patologie   MeSH
• benzhydrylové sloučeniny metabolismus   toxicita   MeSH
• epigeneze genetická MeSH
• fenoly metabolismus   toxicita   MeSH
• fertilita účinky léků   MeSH
• hodnocení rizik MeSH
• IVM techniky MeSH
• kojená zvířata MeSH
• laktace metabolismus   MeSH
• matka - expozice noxám MeSH
• mléko metabolismus   MeSH
• myši inbrední ICR MeSH
• myši MeSH
• oocyty účinky léků   metabolismus   patologie   MeSH
• ovariální rezerva účinky léků   MeSH
• ovarium účinky léků   metabolismus   patofyziologie   MeSH
• sulfony metabolismus   toxicita   MeSH
• těhotenství MeSH
• vývojová regulace genové exprese MeSH
• ženská infertilita chemicky indukované   metabolismus   patologie   patofyziologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• benzhydrylové sloučeniny MeSH
• bis(4-hydroxyphenyl)sulfone MeSH Prohlížeč
• bisphenol F MeSH Prohlížeč
• fenoly MeSH
• sulfony MeSH

The equilibrium dissociation constant of competitive antagonists represents the affinity of the receptor-ligand interaction, and it is a key characteristic of many therapeutic drugs or toxic compounds. Two commonly used methods by which the affinity of the antagonist can be estimated are Schild analysis and the Cheng-Prusoff method. However, both methods yield different results when applied to systems with slopes not equal to one. The Gaddum equation, which is fundamental for both methods, should be extended to incorporate the slope parameter of the dose-response curves and this extension should diminish the differences between the Schild and Cheng-Prusoff methods. In this study, we derived a novel form of the Gaddum equation with a slope parameter (Hill coefficient) of agonist dose-response curve. We also derived the subsequent equations for Schild and Cheng-Prusoff analysis and we validated the proposed model by the measurement of several known estrogen receptor competitive antagonists. Standardized in vitro yeast reporter gene assay (BMAEREluc/ERα) has been used for the measurements and the range of used antagonist concentrations was 1.37-46.03 μM. By applying our mathematical model, both Schild and Cheng-Prusoff methods provide more similar values of antagonist affinity than the original mathematical approach. The correctness of the model has also been demonstrated by the measurement of a partial agonist with a known receptor affinity. The presented mathematical model significantly reduces the differences in values calculated by the Cheng-Prusoff and Schild methods and yields more accurate estimations of antagonist affinity.

• Klíčová slova
• Antagonists, Equilibrium constant, Gaddum equation, Inhibition curve analysis, Receptor theory, Schild analysis,
• MeSH
• alfa receptor estrogenů antagonisté a inhibitory   metabolismus   MeSH
• antagonisté estrogenového receptoru metabolismus   farmakologie   MeSH
• benzhydrylové sloučeniny metabolismus   toxicita   MeSH
• biologické modely * MeSH
• endokrinní disruptory metabolismus   toxicita   MeSH
• estradiol metabolismus   farmakologie   MeSH
• estrogeny metabolismus   farmakologie   MeSH
• fenoly metabolismus   toxicita   MeSH
• kompetitivní vazba MeSH
• lidé MeSH
• ligandy MeSH
• parciální agonismus léků MeSH
• reprodukovatelnost výsledků MeSH
• vazba proteinů MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• alfa receptor estrogenů MeSH
• antagonisté estrogenového receptoru MeSH
• benzhydrylové sloučeniny MeSH
• bisphenol A MeSH Prohlížeč
• endokrinní disruptory MeSH
• estradiol MeSH
• estrogeny MeSH
• fenoly MeSH
• ligandy MeSH

In modern societies, living organisms are exposed daily to multiform pollution from industrial chemical products. Some of these substances have been shown to affect the endocrine system, and have been termed endocrine disruptors (EDs). Bisphenol A (BPA), which can leach from plastics, and parabens, used in cosmetic products, are among the most well-studied. Prenatal development is a vulnerable phase of human life, and disruptions during this period may have lifelong consequences. Since EDs are known to cross the placental barrier and BPA may accumulate in the fetus, "BPA-free" products have been introduced to the market. However, such products often contain alternative bisphenols (e.g. BPS, BPF) that have not yet been extensively examined or regulated. Moreover, alternative bisphenols often occur together with BPA. The human organism is thus exposed to a mixture of EDs, some of which can have additive or synergic effects. Recent findings have also shown that paraben exposure can alter bisphenol pharmacokinetics. Taking into account the widespread occurrence of various EDs and the potential multiplicity of their effects, doses of EDs currently considered safe may not actually be as safe as they appear, especially during pregnancy.

• MeSH
• benzhydrylové sloučeniny škodlivé účinky   metabolismus   MeSH
• endokrinní disruptory škodlivé účinky   metabolismus   MeSH
• fenoly škodlivé účinky   metabolismus   MeSH
• lidé MeSH
• parabeny škodlivé účinky   metabolismus   MeSH
• těhotenství MeSH
• zpožděný efekt prenatální expozice chemicky indukované   metabolismus   patofyziologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• benzhydrylové sloučeniny MeSH
• bisphenol A MeSH Prohlížeč
• endokrinní disruptory MeSH
• fenoly MeSH
• parabeny MeSH

OBJECTIVES: The aim of this study was to compare in silico data with results obtained in two alternative in vitro methods; and to investigate the potential endocrine activity of bisphenol A analogues. This article contributes to recent findings and brings up-to-date information on development of EU legislation and in vitro testing methods of endocrine disruption. METHODS: In silico approach based on the OECD QSAR Toolbox was used for prediction of potential ligands of human estrogen receptor α. Estrogen Receptor Transactivation in vitro Assay to Detect Estrogen Receptor Agonists and Antagonists (OECD TG 455/457) using the VM7Luc4E2 (formerly designated BG1Luc4E2) cell line was performed for measurement of transactivation activity of the tested substances. Commercially available yeast-based microplate assay (XenoScreen YES/YAS, Xenometrix, Switzerland) for detection of compounds with estrogenic and androgenic agonistic/antagonistic activity was used as a comparative test to estrogen receptor transactivation assay (OECD TG 455/457) and for screening of the agonistic/antagonistic potential of human estrogen receptor and agonistic/antagonistic activity of tested compounds on human androgen receptor. RESULTS: The study showed good correlation between the two in vitro assays and significant correlation with in silico data. All tested substances were identified as agonists for human estrogen receptor α by methods in silico and in vitro, four substances showed a potentially higher estrogenic activity comparing to bisphenol A, two substances were identified as very weak antagonists of human androgen receptor and one compound showed a potential of agonistic activity to human androgen receptor. CONCLUSIONS: The study contributes to recent findings and brings new in silico and in vitro data of bisphenol A analogues, revealing that these analogous substances should be further tested as they may show similar or higher activity in vivo comparing to bisphenol A, which has been recently legislatively regulated.

• MeSH
• alfa receptor estrogenů agonisté   antagonisté a inhibitory   metabolismus   MeSH
• benzhydrylové sloučeniny metabolismus   MeSH
• biotest MeSH
• buněčné linie MeSH
• endokrinní disruptory metabolismus   MeSH
• estrogeny nesteroidní metabolismus   MeSH
• fenoly metabolismus   MeSH
• lidé MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• alfa receptor estrogenů MeSH
• benzhydrylové sloučeniny MeSH
• bisphenol A MeSH Prohlížeč
• endokrinní disruptory MeSH
• estrogeny nesteroidní MeSH
• fenoly MeSH

Without any doubt, endocrine-disrupting compounds (EDCs) represent an environmental risk for wildlife and human beings. Endocrine-disrupting effects were found for many chemicals in products for personal use, industrial compounds and even in classical persistent organic pollutants (POPs). In order to understand the fate of EDCs in the environment, it is highly important to identify and to clarify the biodegradation mechanisms that can lead to their decomposition. Ligninolytic fungi (LF) are interesting microorganisms that are capable of participating in a variety of versatile decomposition mechanisms. The microorganisms represent a useful model group and, moreover, LF or their enzymes can be actively used for decontamination. Potential optimization of the decontamination process provides another important reason why it is necessary for understanding the mechanisms of EDC transformation. This minireview summarizes current knowledge about the LF biodegradation mechanisms of the most important micropollutants (xenoestrogens), including nonylphenols, bisphenol A and 17α-ethinylestradiol and polychlorinated biphenyls as POPs with endocrine-disrupting potency. Generally, LF exhibit the ability to either polymerize the target pollutants or to substantially decompose the original structure using ligninolytic enzymes and cytochrome P-450. Moreover, most of the transformation processes are accompanied by reduction of the endocrine-disrupting activity or ecotoxicity.

• MeSH
• benzhydrylové sloučeniny metabolismus   MeSH
• biodegradace * MeSH
• endokrinní disruptory metabolismus   toxicita   MeSH
• estrogeny nesteroidní metabolismus   toxicita   MeSH
• fenoly metabolismus   MeSH
• houby metabolismus   MeSH
• látky znečišťující životní prostředí metabolismus   toxicita   MeSH
• lidé MeSH
• lignin metabolismus   MeSH
• polychlorované bifenyly metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• benzhydrylové sloučeniny MeSH
• bisphenol A MeSH Prohlížeč
• endokrinní disruptory MeSH
• estrogeny nesteroidní MeSH
• fenoly MeSH
• látky znečišťující životní prostředí MeSH
• lignin MeSH
• nonylphenol MeSH Prohlížeč
• polychlorované bifenyly MeSH

Environmental pollutants parathion, bisphenol A and paraquat were not systematically studied towards the effects on the expression of phase I xenobiotics-metabolizing cytochromes P450 (CYPs). We monitored their effects on the expression of selected CYPs in primary cultures of human hepatocytes. Moreover, we investigated their effects on the receptors regulating these CYPs, particularly arylhydrocarbon receptor (AhR), pregnane X receptor (PXR) and glucocorticoid receptor (GR) by gene reporter assays. We found that parathion and bisphenol A are the activators of AhR. Moreover, they are the inducers of CYP1A1 mRNA in hepatoma cells HepG2 as well as in human hepatocytes by AhR-dependent mechanism via formation of AhR-DNA-binding complex, as revealed by gel shift assay. All three compounds possessed anti-glucocorticoid action as revealed by GR-dependent gene reporter assay and a decline in tyrosine aminotransferase (TAT) gene expression in human hepatocytes. Moreover, parathion and bisphenol A are the activators of PXR and inducers of CYP3A4 mRNA and protein in the primary cultures of human hepatocytes. In conclusion, the studied compounds displayed distinct activities towards nuclear receptors involved in many biological processes and these findings may help us to better understand their adverse actions in pathological states followed after their exposure.

• Klíčová slova
• AhR, CYP3A4, Human hepatocytes, PXR, TAT,
• MeSH
• aktivace transkripce účinky léků   MeSH
• benzhydrylové sloučeniny metabolismus   toxicita   MeSH
• buňky Hep G2 MeSH
• enzymová indukce MeSH
• fenoly metabolismus   toxicita   MeSH
• hepatocyty účinky léků   enzymologie   MeSH
• I. fáze biotransformace MeSH
• kultivované buňky MeSH
• látky znečišťující životní prostředí metabolismus   toxicita   MeSH
• lidé středního věku MeSH
• lidé MeSH
• paraquat metabolismus   toxicita   MeSH
• parathion metabolismus   toxicita   MeSH
• pregnanový X receptor MeSH
• primární buněčná kultura MeSH
• receptory aromatických uhlovodíků genetika   metabolismus   MeSH
• receptory glukokortikoidů genetika   metabolismus   MeSH
• regulace genové exprese enzymů účinky léků   MeSH
• reportérové geny MeSH
• steroidní receptory genetika   metabolismus   MeSH
• systém (enzymů) cytochromů P-450 biosyntéza   genetika   MeSH
• viabilita buněk účinky léků   MeSH
• xenobiotika metabolismus   toxicita   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• benzhydrylové sloučeniny MeSH
• bisphenol A MeSH Prohlížeč
• fenoly MeSH
• látky znečišťující životní prostředí MeSH
• paraquat MeSH
• parathion MeSH
• pregnanový X receptor MeSH
• receptory aromatických uhlovodíků MeSH
• receptory glukokortikoidů MeSH
• steroidní receptory MeSH
• systém (enzymů) cytochromů P-450 MeSH
• xenobiotika MeSH

The general population is potentially exposed to many chemicals that can affect the endocrine system. These substances are called endocrine disruptors (EDs), and among them bisphenol A (BPA) is one of the most widely used and well studied. Nonetheless, there are still no data on simultaneous measurements of various EDs along with steroids directly in the seminal fluid, where deleterious effects of EDs on spermatogenesis and steroidogenesis are assumed. We determined levels of BPA and 3 estrogens using LC-MS/MS in the plasma and seminal plasma of 174 men with different degrees of infertility. These men were divided according their spermiogram values into 4 groups: (1) healthy men, and (2) slightly, (3) moderate, and (4) severely infertile men. Estradiol levels differed across the groups and body fluids. Slightly infertile men have significantly higher BPA plasma and seminal plasma levels in comparison with healthy men (p<0.05 and p<0.01, respectively). Furthermore, seminal BPA, but not plasma BPA, was negatively associated with sperm concentration and total sperm count (-0.27; p<0.001 and -0.24; p<0.01, respectively). These findings point to the importance of seminal plasma in BPA research. Overall, a disruption of estrogen metabolism was observed together with a weak but significant impact of BPA on sperm count and concentration.

• MeSH
• benzhydrylové sloučeniny krev   metabolismus   MeSH
• biologické markery krev   metabolismus   MeSH
• dospělí MeSH
• estrogeny krev   metabolismus   MeSH
• fenoly krev   metabolismus   MeSH
• lidé MeSH
• mužská infertilita krev   diagnóza   metabolismus   MeSH
• počet spermií metody   MeSH
• sperma metabolismus   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• benzhydrylové sloučeniny MeSH
• biologické markery MeSH
• bisphenol A MeSH Prohlížeč
• estrogeny MeSH
• fenoly MeSH