Nickel is a ubiquitous environmental pollutant, which has various effects on reproductive endocrinology. In this study, human adrenocortical carcinoma (NCI-H295R) cell line was used as an in vitro biological model to study the effect of nickel chloride (NiCl2) on the viability and steroidogenesis. The cells were exposed to different concentrations (3.90; 7.80; 15.60; 31.20; 62.50; 125; 250 and 500 microM) of NiCl2 and compared with control group (culture medium without NiCl2). The cell viability was measured by the metabolic activity assay. Production of sexual steroid hormones was quantified by enzyme linked immunosorbent assay. Following 48 h culture of the cells in the presence of NiCl2 a dose-dependent depletion of progesterone release was observed even at the lower concentrations. In fact, lower levels of progesterone were detected in groups with higher doses (>/=125 microM) of NiCl2 (P<0.01), which also elicited cytotoxic action. A more prominent decrease in testosterone production (P<0.01) was also noted in comparison to that of progesterone. On the other hand, the release of 17beta-estradiol was substantially increased at low concentrations (3.90 to 62.50 microM) of NiCl2. The cell viability remained relatively unaltered up to 125 microM (P>0.05) and slightly decreased from 250 microM of NiCl2 (P<0.05). Our results indicate endocrine disruptive effect of NiCl2 on the release of progesterone and testosterone in the NCI-H295R cell line. Although no detrimental effect of NiCl2 (

• MeSH
• adrenokortikální karcinom metabolismus   patologie   MeSH
• adrenokortikální nádory metabolismus   patologie   MeSH
• endokrinní disruptory farmakologie   MeSH
• estradiol metabolismus   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• nikl farmakologie   MeSH
• progesteron metabolismus   MeSH
• techniky in vitro MeSH
• testosteron metabolismus   MeSH
• viabilita buněk MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články 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.

• 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

17β-estradiol (estradiol) is a natural estrogen regulating reproduction including sperm and egg development, sperm maturation-called capacitation-and sperm⁻egg communication. High doses can increase germ cell apoptosis and decrease sperm count. Our aim was to answer the biological relevance of estradiol in sperm capacitation and its effect on motility and acrosome reaction to quantify its interaction with estrogen receptors and propose a model of estradiol action during capacitation using kinetic analysis. Estradiol increased protein tyrosine phosphorylation, elevated rate of spontaneous acrosome reaction, and altered motility parameters measured Hamilton-Thorne Computer Assisted Semen Analyzer (CASA) in capacitating sperm. To monitor time and concentration dependent binding dynamics of extracellular estradiol, high-performance liquid chromatography with tandem mass spectrometry was used to measure sperm response and data was subjected to kinetic analysis. The kinetic model of estradiol action during sperm maturation shows that estradiol adsorption onto a plasma membrane surface is controlled by Langmuir isotherm. After, when estradiol passes into the cytoplasm, it forms an unstable adduct with cytoplasmic receptors, which display a signalling autocatalytic pattern. This autocatalytic reaction suggests crosstalk between receptor and non-receptor pathways utilized by sperm prior to fertilization.

• MeSH
• akrozomální reakce účinky léků   MeSH
• estradiol metabolismus   farmakologie   MeSH
• kapacitace spermií účinky léků   fyziologie   MeSH
• kinetika MeSH
• motilita spermií účinky léků   MeSH
• myši inbrední C57BL MeSH
• progesteron farmakologie   MeSH
• signální transdukce * MeSH
• sperma účinky léků   metabolismus   MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Sexual size dimorphism (SSD) reflects sex-specific solutions to the allocation of energy among growth, reproduction and survival; however, the proximate mechanisms behind these solutions are still poorly known even in vertebrates. In squamates, sexual differences in body size used to be attributed to direct energy allocation to energetically demanding processes, largely to reproduction. In addition, SSD is assumed to be controlled by specific endogenous mechanisms regulating growth in a sex-specific manner, namely masculinization by male gonadal androgens or feminization by ovarian hormones. We performed a manipulative growth experiment in females of the male-larger gecko Paroedura picta in order to test the reproductive cost hypothesis, the male androgen hypothesis and the ovarian hormone hypothesis. Specifically, we investigated the effect of total ovariectomy, prepubertal ovariectomy, unilateral ovariectomy, and total ovariectomy followed by exogenous estradiol, dihydrotestosterone or testosterone treatment, on female growth in comparison to males and reproductively active females. The present results and the results of our previous experiments do not support the hypotheses that SSD reflects direct energy allocation to reproduction and that male gonadal androgens are involved. However, all lines of evidence, particularly the comparable growth of reproducing intact and unilaterally ovariectomized females, were concordant with the control of SSD by ovarian hormones. We suggest that feminization of growth by female gonadal hormones should be taken into consideration as an endogenous pathway responsible for the ontogeny of SSD in squamates.

• MeSH
• dihydrotestosteron metabolismus   MeSH
• estradiol metabolismus   MeSH
• ještěři růst a vývoj   fyziologie   MeSH
• ovarektomie MeSH
• ovarium růst a vývoj   fyziologie   MeSH
• pohlavní dimorfismus MeSH
• rozmnožování MeSH
• testosteron metabolismus   MeSH
• velikost těla MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

This study aimed at examining the secretion activity of steroid hormones progesterone and 17beta-estradiol by porcine ovarian granulosa cells after addition of green tea extract. Granulosa cells were incubated with green tea extract (at doses of 0.01, 0.1, 1, 10 and 100 microg.ml(-1). Another set of cells were incubated with green tea extract at the above doses along with additional supplementation of follicle stimulating hormone (FSH) at 10 microg.ml(-1). Release of hormones by granulosa cells was assessed by EIA after 24 h exposure. Secretion of steroid hormones was not affected either by green tea extract alone or after FSH supplementation with green tea extract. Results indicate that ovarian steroidogenesis is not affected by green tea under conditions used in the experiment.

• MeSH
• čajovník čínský * MeSH
• estradiol metabolismus   sekrece   MeSH
• folikulární buňky účinky léků   metabolismus   sekrece   MeSH
• folikuly stimulující hormon farmakologie   MeSH
• fytoterapie MeSH
• kultivované buňky MeSH
• léčivé rostliny MeSH
• progesteron metabolismus   sekrece   MeSH
• rostlinné extrakty izolace a purifikace   farmakologie   MeSH
• Sus scrofa MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

• MeSH
• aplikace kožní * MeSH
• ateroskleróza komplikace   MeSH
• estradiol aplikace a dávkování   farmakokinetika   metabolismus   škodlivé účinky   MeSH
• estrogenní substituční terapie * metody   MeSH
• gely MeSH
• lidé MeSH
• lipoproteiny metabolismus   účinky léků   MeSH
• postmenopauza * MeSH
• transdermální náplast MeSH
• tromboembolie komplikace   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH

Aquaporin proteins (AQPs) are a family of channels expressed in numerous mammalian tissues, where they play a fundamental role in regulating water transport across cell membranes. Based on reports that AQPs are present in the reproductive system and participate in reproductive processes, our aim was to investigate the effect of progesterone (P(4)), estradiol (E(2)), oxytocin (OT), arachidonic acid (AA), forskolin (FSK) and cyclic adenosine monophosphate (cAMP) on AQP1 and AQP5 expression at mRNA and protein levels in porcine uterine explants from Days 14-16 of gestation in order to determine if they play a role in implantation period in pigs. Quantitative real time PCR and Western-blot analysis revealed that the uterine explants treated with FSK and cAMP produce delayed, but long-term effects on AQP1 abundance (24 h) while AQP5 had a rapid and sustained response to FSK and cAMP in protein content (3 and 24 h). AA increases gene and protein content of AQP1 after longer exposition whereas AQP5 increases after 3 h only at the protein level. Both AQPs potentially remains under control of steroid hormones. OT has been shown to increase AQP1, and decrease AQP5 mRNA, without visible changes in protein content. P(4), E(2), AA, FSK and cAMP caused the appearance of AQP5 expression in the basolateral plasma membrane of the epithelial cells. The staining represents most likely AQP5 functioning mechanism for both absorption and reabsorption across the glandular epithelium.

• MeSH
• akvaporin 1 metabolismus   MeSH
• akvaporin 5 metabolismus   MeSH
• AMP cyklický metabolismus   MeSH
• estradiol metabolismus   MeSH
• implantace embrya * MeSH
• imunohistochemie MeSH
• kolforsin metabolismus   MeSH
• kyselina arachidonová metabolismus   MeSH
• oxytocin metabolismus   MeSH
• prasata MeSH
• progesteron metabolismus   MeSH
• techniky in vitro MeSH
• těhotenství MeSH
• uterus metabolismus   MeSH
• zvířata MeSH
• Check Tag
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The present study suggests and describes the application of a delivery system for antisense oligonucleotides against mRNA encoding estrogen receptor proteins α and β. The delivery system is composed of a cationic liposome envelope containing 17β-estradiol (E2) in its structure. Cationic liposomes protect cargo against the extracellular matrix, and E2 can increase its shuttling efficiency into cells. Using MCF-7 cells derived from estrogen receptor-positive ductal carcinoma, treatment with liposomes against ERα was found to decrease MCF-7 proliferation, and importantly the application of both the antisense against ERα and β exhibited an antiproliferative effect expressed as cell viability. Using qRT-PCR, it was shown that MT1A, NF-κB1 and K-ras genes, but not TFF1, were downregulated using E2-based liposomes (evaluated at P=0.05). Further indicators of oxidative stress were employed to assess the effect on treatment efficiency. Glutathione (GSH/GSSG redox ratio), metallothionein (MT) and malondialdehyde (MDA) confirmed a positive effect of antisense therapy resulting in their decreased levels in the MCF-7 cells. Based on these data, we suggest that E2-based liposomes offer sufficient transfer efficiency and moreover, due to the effect on NF-κB1, MT and GSH, tumor cells can be chemosensitized to increase treatment effectiveness.

• MeSH
• antitumorózní látky chemie   MeSH
• estradiol metabolismus   MeSH
• genetická terapie metody   MeSH
• glutathion chemie   MeSH
• koncentrace vodíkových iontů MeSH
• kyslík chemie   MeSH
• lidé MeSH
• liposomy chemie   MeSH
• malondialdehyd chemie   MeSH
• metalothionein chemie   MeSH
• MFC-7 buňky MeSH
• mikroskopie fázově kontrastní MeSH
• nádorové buněčné linie MeSH
• nádory prsu metabolismus   MeSH
• oxidace-redukce MeSH
• oxidační stres MeSH
• proliferace buněk MeSH
• receptory pro estrogeny metabolismus   MeSH
• regulace genové exprese MeSH
• systémy cílené aplikace léků * MeSH
• viabilita buněk MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Beyond the role of 17β-estradiol (E2) in reproduction and during the menstrual cycle, it has been shown to modulate numerous physiological processes such as cell proliferation, apoptosis, inflammation and ion transport in many tissues. The pathways in which estrogens affect an organism have been partially described, although many questions still exist regarding estrogens' interaction with biomacromolecules. Hence, the present study showed the interaction of four oligonucleotides (17, 20, 24 and/or 38-mer) with E2. The strength of these interactions was evaluated using optical methods, showing that the interaction is influenced by three major factors, namely: oligonucleotide length, E2 concentration and interaction time. In addition, the denaturation phenomenon of DNA revealed that the binding of E2 leads to destabilization of hydrogen bonds between the nitrogenous bases of DNA strands resulting in a decrease of their melting temperatures (Tm). To obtain a more detailed insight into these interactions, MALDI-TOF mass spectrometry was employed. This study revealed that E2 with DNA forms non-covalent physical complexes, observed as the mass shifts for app. 270 Da (Mr of E2) to higher molecular masses. Taken together, our results indicate that E2 can affect biomacromolecules, as circulating oligonucleotides, which can trigger mutations, leading to various unwanted effects.

• MeSH
• DNA metabolismus   MeSH
• estradiol metabolismus   MeSH
• lidé MeSH
• spektrofotometrie ultrafialová MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The fungicide vinclozolin (VZ) is in use globally and known to disrupt reproductive function in male. The present study tested the hypothesis that VZ disrupts testicular function in goldfish (Carassius auratus) by affecting brain-pituitary-testis axis. Goldfish were exposed to 100, 400 and 800 μg/L VZ and 5 μg/L 17β-estradiol (E2) for comparison. In VZ treated goldfish, 11-ketotesteosterone (11-KT) secretion was changed depending on dose and duration period of treatment. Following 7 days of exposure, 11-KT was decreased in goldfish exposed to 800 μg/L VZ, while it was increased in goldfish exposed to 100 μg/L VZ after 30 days of exposure. Circulating E2 level was unchanged in VZ treated goldfish, however the E2/11-KT ratio was increased in a concentration-related manner. In E2 treated goldfish, circulatory 11-KT and E2 levels were decreased and increased, respectively, which resulted in an increase in the E2/11-KT ratio. Exposure to VZ at 100 μg/L caused a significant increase in the circulatory luteinizing hormone (LH) after 30 days. In E2 treated fish circulatory LH was decreased, significantly. Transcripts of genes encoding gonadotropin-releasing hormone and androgen receptor in the brain, and those of genes encoding LH and follicle-stimulating hormone receptors, StAR, CYP17, and 3β-HSD in the testis changed in VZ-treated goldfish depending on concentration and period of treatment. mRNA of genes encoding vitellogenin and estrogen receptor in the liver and cytochrome P450 aromatase in the brain were increased in E2-treated goldfish. The results suggest that VZ-induced changes in 11-KT were due to disruption in brain-pituitary-testis axis and provide integrated characterization of VZ-related reproductive disorders in male fish.

• MeSH
• aromatasa metabolismus   MeSH
• chemické látky znečišťující vodu aplikace a dávkování   toxicita   MeSH
• estradiol metabolismus   MeSH
• hormon uvolňující gonadotropiny metabolismus   MeSH
• hypofýza účinky léků   metabolismus   MeSH
• játra účinky léků   metabolismus   MeSH
• karas zlatý * MeSH
• oxazoly aplikace a dávkování   toxicita   MeSH
• rozmnožování účinky léků   fyziologie   MeSH
• testis účinky léků   metabolismus   MeSH
• vitelogeniny metabolismus   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH