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1.
Toxicol In Vitro ; 41: 1-11, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28179152

RESUMO

Selective serotonin reuptake inhibitors (SSRIs) used as first line of treatment in major depressive disorder (MDD) are known to exert negative effects on the endocrine system and fertility. The aim of the present study was to investigate the possible endocrine disrupting effect of six SSRIs, fluoxetine, paroxetine, citalopram and its active enantiomer escitalopram, sertraline and fluvoxamine using the OECD standardized and validated human in vitro adrenocortical H295R cell assay. All the major steroids, including progestagens, corticosteroids, androgens and estrogens were analysed using a fully validated LC-MS/MS method. All 6 SSRIs were found to exert endocrine disrupting effects on steroid hormone synthesis at concentrations just around Cmax. Although the mechanisms of disruption were all different, they all resulted in decreased testosterone levels, some due to effects on CYP17, some earlier in the pathway. Furthermore, all SSRIs relatively increased the estrogen/androgen ratio, indicating stimulating effects on the aromatase. Our study demonstrates the potential of SSRIs to interfere with steroid production in the H295R cells around Cmax levels and indicates that these drugs should be investigated further to determine any hazards for the users.


Assuntos
Androgênios/metabolismo , Antidepressivos/farmacologia , Disruptores Endócrinos/farmacologia , Estrogênios/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Esteroides/metabolismo , Aromatase/metabolismo , Linhagem Celular , Citalopram/farmacologia , Família 21 do Citocromo P450/metabolismo , Fluoxetina/farmacologia , Fluvoxamina/farmacologia , Humanos , Paroxetina/farmacologia , Sertralina/farmacologia , Esteroide 17-alfa-Hidroxilase/metabolismo
2.
Anal Bioanal Chem ; 408(18): 4883-95, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27150205

RESUMO

Measuring both progestagens, androgens, corticosteroids as well as estrogens with a single method makes it possible to investigate the effects of endocrine-disrupting chemicals (EDCs) on the main pathways in the mammalian steroidogenesis. This paper presents two simple methods for the determination of the major steroid hormones in biological matrixes using liquid chromatography tandem mass spectrometry (LC-MS(2)). A novel method was developed for the determination of 14 steroids in the H295R in vitro assay without the need for solid phase extraction (SPE) purification prior to LC-MS(2) analysis. The in vitro assay was validated by exposing H295R cells to prochloraz for inhibiting steroid hormone secretion and by exposing cells to forskolin for inducing steroid hormone secretion. The developed method fulfills the recommendations for the H295R assay suggested by the OECD. Furthermore, a simple off-line SPE methodology was developed for the necessary clean-up of in vivo assays. Samples, such as gonad tissue, plasma and serum, are complex biological matrixes, and the SPE methodology was optimized to remove salts and proteins prior to elution of target analytes. At the same time, lipophilic compounds were retained on the SPE cartridge during elution. This, combined with the multi-steroid LC-MS(2) method, made it possible to determine 10 steroids in male Sprague-Dawley rat gonad tissue. Furthermore, it was possible to quantify 6 steroids in the plasma. In general, the observed concentration of steroid hormones in plasma, testes, and H295R cell medium corresponded well with previous studies. The off-line SPE method was validated using spiked charcoal-stripped serum. Method recovery, accuracy, precision and robustness were all good. Instrument sensitivity was in the range of 55-530 pg/mL (LLOQ).


Assuntos
Bioensaio/métodos , Cromatografia Líquida/métodos , Disruptores Endócrinos/administração & dosagem , Hormônios Esteroides Gonadais/metabolismo , Espectrometria de Massas/métodos , Manejo de Espécimes/métodos , Testículo/metabolismo , Animais , Linhagem Celular Tumoral , Hormônios Esteroides Gonadais/sangue , Humanos , Técnicas In Vitro , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Testículo/efeitos dos fármacos
3.
Toxicol In Vitro ; 34: 71-80, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27002602

RESUMO

Enantiomers possess different pharmacokinetic and pharmacodynamic properties and this may not only influence the therapeutic effect of a drug but also its toxicological effects. In the present work we investigated the potential enantioselective endocrine disrupting effects of omeprazole (OME) and its two enantiomers on the human steroidogenesis using the H295R cell line. Differences in production of 16 steroid hormones were analyzed using LC-MS/MS. Additionally, to evaluate the differences in binding modes of these enantiomers, docking and molecular dynamics (MD) simulations of S-omeprazole (S-OME) and R-omeprazole (R-OME) in CYP17A1, CYP19A1 and CYP21A2 were carried out. Exposing H295R cells to OME and its enantiomers resulted in an increase of progesterone (PRO) and 17α-hydroxy-progesterone (OH-PRO) levels. At the same time, a decrease in the corticosteroid and androgen synthesis was observed, indicating inhibition of CYP21A2 and CYP17A1. In both cases, the effect of R-OME was smaller compared to that of the S-OME and a certain degree of enantioselectivity of CYP17A1 and CYP21A2 was suggested. Docking indicated that the N-containing rings of OME possibly could interact with the iron atom of the heme for S-OME in CYP17A1 and S- and R-OME in CYP21A2. However, density functional theory calculations suggest that the direct N-Fe interaction is weak. The study demonstrates enantioselective differences in the endocrine disrupting potential of chiral drugs such as omeprazole. These findings may have potential implications for drug safety and drug design.


Assuntos
Disruptores Endócrinos/toxicidade , Modelos Moleculares , Omeprazol/toxicidade , Aromatase/metabolismo , Linhagem Celular , Cromatografia Líquida , Disruptores Endócrinos/química , Humanos , Omeprazol/química , Estereoisomerismo , Esteroide 17-alfa-Hidroxilase/metabolismo , Esteroide 21-Hidroxilase/metabolismo , Espectrometria de Massas em Tandem
4.
Toxicol Sci ; 150(1): 178-89, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26732887

RESUMO

Studies report that fetal exposure to paracetamol/acetaminophen by maternal consumption can interfere with male reproductive development. Moreover, recent biomonitoring data report widespread presence of paracetamol in German and Danish populations, suggesting exposure via secondary (nonpharmaceutical) sources, such as metabolic conversion from the ubiquitous industrial compound aniline. In this study, we investigated the extent to which paracetamol and aniline can interfere with female reproductive development. Intrauterine exposure to paracetamol by gavage of pregnant dams resulted in shortening of the anogenital distance in adult offspring, suggesting that fetal hormone signaling had been disturbed. Female offspring of paracetamol-exposed mothers had ovaries with diminished follicle reserve and reduced fertility. Fetal gonads of exposed animals had also reduced gonocyte numbers, suggesting that the reduced follicle count in adults could be due to early disruption of germ cell development. However, ex vivo cultures of ovaries from 12.5 days post coitum fetuses showed no decrease in proliferation or expression following exposure to paracetamol. This suggests that the effect of paracetamol occurs prior to this developmental stage. Accordingly, using embryonic stem cells as a proxy for primordial germ cells we show that paracetamol is an inhibitor of cellular proliferation, but without cytotoxic effects. Collectively, our data show that intrauterine exposure to paracetamol at levels commonly observed in pregnant women, as well as its precursor aniline, may block primordial germ cell proliferation, ultimately leading to reduced follicle reserves and compromised reproductive capacity later in life.


Assuntos
Acetaminofen/toxicidade , Compostos de Anilina/toxicidade , Fertilidade/efeitos dos fármacos , Genitália Feminina/anormalidades , Folículo Ovariano/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Animais , Feminino , Genitália Feminina/embriologia , Idade Gestacional , Masculino , Camundongos Endogâmicos C57BL , Folículo Ovariano/embriologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/patologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia
5.
Reprod Toxicol ; 58: 174-83, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26476359

RESUMO

Endocrine modulating effects of Simvastatin (SV) and its metabolite, Simvastatin ß-hydroxy acid (SVA), were investigated in H295R cells and in female Sprague-Dawley (SPRD) rats. H295R cells were exposed to SV and SVA concentrations from 0 to 10µM for 48h. Four groups of SPRD rats received 0 (CT), 1.3 (L), 5.0 (M), and 20.0 (H)mg SV/kg bw/day for 14 days. 10 Steroids were investigated in H295R growth media, and in tissues and plasma from rats using GC-MS/MS. Plasma LH and FSH were quantified by ELISA. In the H295R assay, SV and SVA particularly decreased progestagens with IC50-values from 0.10-0.13µM for SV and from 0.019-0.055µM for SVA. In rats, SV decreased progestagens in ovaries, brain and plasma, and plasma FSH in the M (72.4% decrease) and H group (76.6% decrease). Because progestagens and gonadotropins are major players in fertility, administration of SV might exert negative effects on female reproduction.


Assuntos
Córtex Suprarrenal/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Hormônio Foliculoestimulante/biossíntese , Hormônios Esteroides Gonadais/biossíntese , Inibidores de Hidroximetilglutaril-CoA Redutases/toxicidade , Sinvastatina/toxicidade , Córtex Suprarrenal/metabolismo , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Feminino , Fertilidade/efeitos dos fármacos , Hormônio Foliculoestimulante/sangue , Cromatografia Gasosa-Espectrometria de Massas , Hormônios Esteroides Gonadais/sangue , Hormônio Luteinizante/biossíntese , Hormônio Luteinizante/sangue , Ratos Sprague-Dawley , Reprodução/efeitos dos fármacos , Medição de Risco , Espectrometria de Massas em Tandem , Fatores de Tempo
6.
Int J Toxicol ; 34(6): 534-42, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26268768

RESUMO

Mixture effects of 3 model endocrine disruptors, prochloraz, ketoconazole, and genistein, on steroidogenesis were tested in the adrenocortical H295R cell line. Seven key steroid hormones (pregnenolone, progesterone, dehydroepiandrosterone, androstenedione, testosterone, estrone, and 17ß-estradiol) were analyzed using gas chromatography and tandem mass spectrometry (GC-MS/MS) to investigate the effects throughout the steroidogenic pathway. Current modeling approaches often rely on models assuming compounds acting independently and that the individual effects in some way can be summarized to predict a mixture effect. In H295R cells with an intact steroidogenic pathway, such assumptions may not be feasible. The purpose of this study was therefore to evaluate whether effects of a mixture with differing modes of action followed or deviated from additivity (concentration addition) and whether the H295R cell line was suitable for evaluating mixture toxicity of endocrine disruptors with different modes of action. The compounds were chosen because they interfere with steroidogenesis in different ways. They all individually decrease the concentrations of the main sex steroids downstream but exert different effects upstream in the steroidogenic pathway. Throughout the study, we observed lowest observed effect concentrations of mixtures at levels 2 to 10 times higher than the predicted EC(50), strongly indicating antagonistic effects. The results demonstrate that chemical analysis combined with the H295R cell assay is a useful tool also for studying how mixtures of endocrine disruptors with differing modes of action interfere with the steroidogenic pathway and that existing models like concentration addition are insufficient in such cases. Furthermore, for end points where compounds exert opposite effects, no relevant models are available.


Assuntos
Disruptores Endócrinos/toxicidade , Genisteína/toxicidade , Imidazóis/toxicidade , Cetoconazol/toxicidade , Esteroides/biossíntese , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Interações Medicamentosas , Humanos
7.
Toxicol In Vitro ; 29(7): 1729-35, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26162595

RESUMO

Selective serotonin reuptake inhibitors are known to have a range of disorders that are often linked to the endocrine system e.g. hormonal imbalances, breast enlargement, sexual dysfunction, and menstrual cycle disorders. The mechanisms behind most of these disorders are not known in details. In this study we investigated whether the endocrine effect due to SSRI exposure could be detected in well adopted in vitro steroidogenesis assays, two versions of the aromatase enzyme inhibition assay and the H295R cell assay. The five drugs citalopram, fluoxetine, fluvoxamine, paroxetine and sertraline, were shown to inhibit the aromatase enzyme in both types of aromatase assays. The IC50 values ranged from 3 to 600 µM. All five SSRIs, were further investigated in the H295R cell line. All compounds altered the steroid secretion from the cells, the lowest observed effect levels were 0.9 µM and 3.1 µM for sertraline and fluvoxamine, respectively. In general the H295R cell assay was more sensitive to SSRI exposure than the two aromatase assays, up to 20 times more sensitive. This indicates that the H295R cell line is a better tool for screening endocrine disrupting effects. Our findings show that the endocrine effects of SSRIs may, at least in part, be due to interference with the steroidogenesis.


Assuntos
Inibidores da Aromatase/farmacologia , Estradiol/metabolismo , Progesterona/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Testosterona/metabolismo , Aromatase/metabolismo , Linhagem Celular Tumoral , Citalopram/farmacologia , Fluoxetina/farmacologia , Fluvoxamina/farmacologia , Humanos , Paroxetina/farmacologia , Sertralina/farmacologia
8.
Toxicol In Vitro ; 26(2): 343-50, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22198065

RESUMO

The effects of three model endocrine disruptors, prochloraz, ketoconazole and genistein on steroidogenesis were tested in the adrenocortical H295R cell line to demonstrate that a broader mechanistic understanding can be achieved in one assay by applying chemical analysis to the H295R assay. Seven key steroid hormones (pregnenolone, progesterone, dehydroepiandrosterone, androstenedione, testosterone, estrone and 17ß-estradiol) were analyzed using a novel and thoroughly validated GC-MS/MS method. In addition to the simultaneous quantification of 7 steroid hormones, the present method also negates the potential problems of cross-reactivity that can be encountered in some immunoassays. Although all 3 test compounds decrease the concentrations of the main sex steroids, the chemicals exerted different effects upstream in the pathway. Exposure to prochloraz resulted in increased hormone levels upstream of steroid 17 alpha-hydroxylase/17,20 lyase (P450c17) and decreases downstream. Ketoconazole inhibited the entire pathway, while exposure to genistein resulted in increased hormone levels upstream of 3-ß-hydroxysteroid dehydrogenase (3ß-HSD) and decreases downstream. The results demonstrate that chemical analysis combined with the H295R cell assay is an useful tool for studying the mechanisms by which endocrine disruptors interfere with the steroidogenic pathway.


Assuntos
Disruptores Endócrinos/farmacologia , Genisteína/farmacologia , Hormônios Esteroides Gonadais/metabolismo , Imidazóis/farmacologia , Cetoconazol/farmacologia , Esteroides/metabolismo , Bioensaio/métodos , Linhagem Celular Tumoral , Cromatografia Gasosa , Humanos , Espectrometria de Massas em Tandem
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