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1.
J Pharm Biomed Anal ; 162: 34-40, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30219597

RESUMO

BACKGROUND: Comprehensive serum sex hormone profiling is essential for monitoring the occurrence and development of many related diseases. However, the current methods for multi-class sex hormone detection were always lack of Standard Reference Material (SRM) certification and suffered from large sample consumption. For improvement, we developed a new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method focused on SRM certification and minimization of serum consumption for simultaneous quantification of seven mainstream serum sex hormones including estrogens (estrone E1, estradiol E2 and estriol E3), androgens (testosterone T, androstenedione AD, dehydroepiandrosterone DHEA) and progestogens (progesterone P). METHODS: To achieve one-batch analysis, a straightforward strategy was designed and carefully optimized. Schematically, serum was firstly spiked with isotope-labeled internal standards. Then, liquid-liquid extraction was performed with methyl tert-butyl ether. After drying under nitrogen, dansyl chloride was introduced for derivatization. Finally, the mixture was submitted to LC-MS/MS for quantification. RESULTS: The limit of quantification was 0.005 ng/mL for E1, E2 and E3, 0.01 ng/mL for T, P and AD, 0.25 ng/mL for DHEA. Inter- and intra-assay CVs were less than 11.8%. The selectivity was proved satisfactory by interference spiking tests. With systematical SRM validation, the mean bias of -5.4 to 4.7% was observed, which indicated excellent method reliability. We found significant positive bias in chemiluminescence immunoassay (CLIA) detection comparing with current method, which promoted us to reconsider our previous results on sex hormone regulation in male patients with coronary atherosclerotic disease. After redetecting the related samples, modified and improved conclusions were proposed. CONCLUSIONS: A LC-MS/MS method for multi-class serum sex hormone profiling was developed with SRM certification and minimized serum consumption. Taking advantages of such reliable method, the previous CLIA-based research findings on sex hormone regulation in male patients with coronary atherosclerosis were modified and improved after redetecting the same sample-pool.


Assuntos
Análise Química do Sangue/métodos , Cromatografia Líquida , Doença da Artéria Coronariana/sangue , Hormônios Esteroides Gonadais/sangue , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Idoso , Androstenodiona/sangue , Androstenóis/sangue , Análise Química do Sangue/normas , Calibragem , Estudos de Casos e Controles , Cromatografia Líquida/normas , Doença da Artéria Coronariana/diagnóstico , Estranos/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Progesterona/sangue , Padrões de Referência , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/normas , Espectrometria de Massas em Tandem/normas , Testosterona/sangue
2.
Steroids ; 147: 4-9, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30296546

RESUMO

Neurosteroids are endogenous steroidal compounds that can modulate neuronal receptors. N-Methyl-D-aspartate receptors (NMDARs) are glutamate-gated, calcium-permeable ion channels that are of particular interest, as they participate in synaptic transmission and are implicated in various processes, such as learning, memory, or long-term neuronal potentiation. Positive allosteric modulators that increase the activity of NMDARs may provide a therapeutic aid for patients suffering from neuropsychiatric disorders where NMDAR hypofunction is thought to be involved, such as intellectual disability, autism spectrum disorder, or schizophrenia. We recently described a new class of pregn-5-ene and androst-5-ene 3ß-dicarboxylic acid hemiesters (2-24) as potent positive modulators of NMDARs. Considering the recommended guidelines for the early stage development of new, potent compounds, we conducted an in vitro safety assessment and plasma stability screening to evaluate their druglikeness. First, compounds were screened for their hepatotoxicity and mitochondrial toxicity in a HepG2 cell line. Second, toxicity in primary rat postnatal neurons was estimated. Next, the ability of compounds 2-24 to cross a Caco-2 monolayer was also studied. Finally, rat and human plasma stability screening revealed an unforeseen high stability of the C-3 hemiester moiety. In summary, by using potency/efficacy towards NMDARs data along with toxicity profile, Caco-2 permeability and plasma stability, compounds 14 and 15 were selected for further in vivo animal studies.


Assuntos
Androstenóis/farmacologia , Colesterol/farmacologia , Ácidos Dicarboxílicos/farmacologia , Ésteres/farmacologia , Fármacos Neuroprotetores/farmacologia , Pregnenolona/análogos & derivados , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Androstenóis/sangue , Androstenóis/química , Animais , Transtorno do Espectro Autista/tratamento farmacológico , Transtorno do Espectro Autista/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Colesterol/sangue , Colesterol/química , Ácidos Dicarboxílicos/sangue , Ácidos Dicarboxílicos/química , Estabilidade de Medicamentos , Ésteres/sangue , Ésteres/química , Células Hep G2 , Humanos , Deficiência Intelectual/tratamento farmacológico , Deficiência Intelectual/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estrutura Molecular , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/sangue , Fármacos Neuroprotetores/química , Pregnenolona/sangue , Pregnenolona/farmacologia , Ratos , Ratos Wistar , Receptores de N-Metil-D-Aspartato/metabolismo , Esquizofrenia/tratamento farmacológico , Esquizofrenia/metabolismo , Células Tumorais Cultivadas
3.
Steroids ; 138: 1-5, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29883615

RESUMO

The purpose of this study was to identify the C11-oxy C19 and C11-oxy C21 steroids in male and female neonate plasma. At birth, the most abundant C11-oxy steroids detected in neonatal plasma were 11ß-hydroxyandrostenedione, ∼13 nM, and 11-ketoprogesterone, ∼23 nM. C11-oxy C19 steroids were higher than C19 steroids in neonatal plasma, 22.2 nM vs 5.4 nM. The inclusion of C11-oxy C19 and C21 steroid reference ranges in routine steroid analyses will assist the characterization of disorders associated with impaired steroidogenic enzyme expression and the identification of potential biomarkers.


Assuntos
Androstenóis/sangue , Progesterona/análogos & derivados , Esteroides/sangue , Espectrometria de Massas em Tandem/métodos , Testosterona/análogos & derivados , Feminino , Humanos , Recém-Nascido , Masculino , Progesterona/sangue , Testosterona/sangue
6.
J Sex Med ; 12(2): 358-73, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25475395

RESUMO

INTRODUCTION: For women, the correlation between circulating androgens and sexual desire is inconclusive. Substitution with androgens at physiological levels improves sexual function in women who experience decreased sexual desire and androgen deficiency from surgical menopause, pituitary disease, and age-related decline in androgen production in the ovaries. Measuring bioactive testosterone is difficult and new methods have been proposed, including measuring the primary androgen metabolite androsterone glucuronide (ADT-G). AIM: The aim of this study was to investigate a possible correlation between serum levels of androgens and sexual desire in women and whether the level of ADT-G is better correlated than the level of circulating androgens with sexual desire. METHODS: This was a cross-sectional study including 560 healthy women aged 19-65 years divided into three age groups. Correlations were considered to be statistically significant at P<0.05. MAIN OUTCOME MEASURE: Sexual desire was determined as the total score of the sexual desire domain of the Female Sexual Function Index. Total testosterone (TT), calculated free testosterone (FT), androstenedione, dehydroepiandrosterone sulfate (DHEAS), and ADT-G were analyzed using mass spectrometry. RESULTS: Sexual desire correlated overall with FT and androstenedione in the total cohort of women. In a subgroup of women aged 25-44 years with no use of systemic hormonal contraception, sexual desire correlated with TT, FT, androstenedione, and DHEAS. In women aged 45-65 years, androstenedione correlated with sexual desire. No correlations between ADT-G and sexual desire were identified. CONCLUSIONS: In the present study, FT and androstenedione were statistically significantly correlated with sexual desire in the total cohort of women. ADT-G did not correlate more strongly than circulating androgens with sexual desire and is therefore not superior to measuring circulating androgens by mass spectrometry.


Assuntos
Androgênios/sangue , Androstenóis/sangue , Libido/fisiologia , Adulto , Fatores Etários , Idoso , Androstenodiona/sangue , Androsterona/análogos & derivados , Androsterona/sangue , Estudos Transversais , Sulfato de Desidroepiandrosterona/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fatores Socioeconômicos , Testosterona/sangue , Saúde da Mulher
7.
Cancer Sci ; 105(10): 1313-20, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25117615

RESUMO

Persistent androgen synthesis under castration status in adrenal gland, testes and tumor cells is thought to be one of the major causes of development and progression of castration-resistant prostate cancer (CRPC). Abiraterone acetate (AA), the prodrug of abiraterone, which is an inhibitor of androgen synthesis enzymes, was evaluated for pharmacokinetics, pharmacodynamics, preliminary efficacy and safety in Japanese patients with CRPC in a phase-1, open-label and dose-escalation study. Chemotherapy-naïve Japanese CRPC patients (N = 27) received one of four AA daily doses (250 mg [n = 9], 500 mg [n = 6], 1000 [1 h premeal] mg [n = 6] and 1000 [2 h postmeal] mg [n = 6]) continuously through 28-day treatment cycles. In the first cycle, AA monotherapy was given on days 1-7 for pharmacokinetics, and AA plus prednisone (5 mg twice daily) from days 8 to 28. Of 27 patients, 9 continued treatment with AA until the data cut-off date (18 July 2013). Over the evaluated dose range, plasma abiraterone concentrations increased with dose, with median tmax 2-3 h. At each dose level, mean serum corticosterone concentrations increased, while testosterone and dehydroepiandrosterone sulfate concentrations rapidly decreased following a single AA dose and were further reduced to near the quantification limit on day 8 regardless of the dose. At least 3 patients from each dose-group experienced ≥50% prostate-specific antigen reduction, suggesting clinical benefit from AA in Japanese CRPC patients. AA was generally well-tolerated, and, therefore, the recommended AA dosage regimen in Japanese CRPC patients is 1000 mg oral dose under modified fasting conditions (at least 1 h premeal or 2 h postmeal). This study is registered at ClinicalTrials.gov: NCT01186484.


Assuntos
Androstadienos/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Esteroide 17-alfa-Hidroxilase/antagonistas & inibidores , Acetato de Abiraterona , Idoso , Idoso de 80 Anos ou mais , Androstadienos/efeitos adversos , Androstenos , Androstenóis/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Neoplasias de Próstata Resistentes à Castração/sangue
8.
J Fluoresc ; 23(6): 1279-86, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23835913

RESUMO

A novel spectrofluorimetric method to determine abiraterone acetate and its active metabolite, abiraterone was developed, based on the fact that fluorescence intensity of abiraterone acetate and abiraterone could be enhanced in ß-cyclodextrin (ß-CD) due to the formation of the inclusion complex. The inclusion interaction of ß-CD and abiraterone acetate and the ß-cyclodextrin sensitized spectrofluorimetry was examined. The various factors influencing fluorescence were discussed in details. The results showed that under the optimized conditions, the linear range of calibration curve for the determination of biraterone acetate and abiraterone was 0.20 ~ 6.0 µg/mL, and the detection limit (LOD) was 6.8 (r = 0.997) or 6.6 ng/mL (r = 0.996), respectively. No interference was observed from common co-existing substances or pharmaceutical excipient. The method was successfully applied to the analysis of abiraterone acetate in pharmaceutical formulation and abiraterone in human serum/urine.


Assuntos
Androstadienos/sangue , Androstadienos/urina , Androstenóis/sangue , Androstenóis/urina , Corantes Fluorescentes/química , Espectrometria de Fluorescência/métodos , beta-Ciclodextrinas/química , Acetato de Abiraterona , Androstenos , Voluntários Saudáveis , Humanos , Concentração de Íons de Hidrogênio , Estrutura Molecular , Concentração Osmolar , Espectrometria de Fluorescência/instrumentação , Temperatura , Fatores de Tempo
9.
J Clin Endocrinol Metab ; 98(3): 1182-8, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23386646

RESUMO

CONTEXT: A broad analysis of adrenal gland-derived 19-carbon (C19) steroids has not been reported. This is the first study that uses liquid chromatography-tandem mass spectrometry to quantify 9 C19 steroids (androgens and their precursors), estrone, and estradiol in the adrenal vein (AV) of women, before and after ACTH stimulation. OBJECTIVE: The objective of this study was to define the adrenal androgen metabolome in women before and after ACTH infusion. DESIGN: This was a retrospective study. PATIENTS: Seven women, aged 50.4 ± 5.4 years, with suspected diagnosis of an adrenal aldosterone-producing adenoma were included in the study. METHODS: AV and iliac serum samples were collected before and after administration of ACTH (15 minutes). AV samples were analyzed using for concentrations of 9 unconjugated C19 steroids, estrone, and estradiol. Dehydroepiandrosterone sulfate (DHEA-S) was quantified by radioimmunoassay. RESULTS: AV levels of DHEA-S were the highest among the steroids measured. The most abundant unconjugated C19 steroids in AV were 11ß-hydroxyandrostenedione (11OHA), dehydroepiandrosterone (DHEA), and androstenedione (A4). ACTH significantly increased the adrenal output of 9 of the 12 steroids that were measured. ACTH increased the mean AV concentration of DHEA-S by 5-fold, DHEA by 21-fold, A4 by 7-fold, and 11OHA by 5-fold. 11ß-Hydroxytestosterone and testosterone were found to be potent androgen receptor agonists when tested with an androgen-responsive cell reporter model. CONCLUSION: The current study indicates that the adrenal gland secretes primarily 3 weak androgens, namely DHEA, 11OHA, and A4. Active androgens, including testosterone and 11ß-hydroxytestosterone, are also produced but to a lesser degree.


Assuntos
Córtex Suprarrenal/efeitos dos fármacos , Hormônio Adrenocorticotrópico/administração & dosagem , Androgênios/sangue , Córtex Suprarrenal/irrigação sanguínea , Androstenodiona/sangue , Androstenóis/sangue , Células Cultivadas , Cromatografia Líquida , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/sangue , Estradiol/sangue , Estrona/sangue , Feminino , Hormônios/administração & dosagem , Humanos , Metaboloma/fisiologia , Pessoa de Meia-Idade , Receptores Androgênicos/metabolismo , Estudos Retrospectivos , Espectrometria de Massas em Tandem , Testosterona/sangue , Veias
10.
Xenobiotica ; 43(4): 379-89, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23020788

RESUMO

1. Metabolic disposition of (14)C-abiraterone acetate (AA), a prodrug of abiraterone was assessed in a phase I, open-label, single-dose (1000 mg, approximately 100 µCi) study in healthy males (18-55 years, N = 8). Blood, urine, and faecal samples were obtained at specified timepoints for determination of abiraterone concentrations in the plasma, total radioactivity (TR), and the metabolite profile. 2. Most plasma AA concentrations were below the limit of quantification. The mean maximum plasma concentration (Cmax) of abiraterone was 10.4 ng/mL, mean area under the plasma concentration-time curve (AUC) from 0 to the last measurable plasma concentration (AUC0-last) was 74.8 ng·h/mL. The exposures for TR in plasma (Cmax = 3429 ng·eq/mL; AUC0-last = 26,683 ng eq·h/mL) and whole blood (Cmax = 1836 ng·eq/mL; AUC0-last = 12,162 ng·eq·h/mL) were >300-fold higher than abiraterone exposure in plasma. The majority of TR resided in the plasma compartment of blood. 3. Main circulating metabolites were abiraterone sulfate and N-oxide abiraterone sulfate. The main metabolite excreted in urine was N-oxide abiraterone sulfate (4.22% of TR). Major components of TR in faeces were unchanged AA (55.3% of TR) and abiraterone (22.3% of TR). Mean recovery of TR in faeces was 87.9%, indicating faeces as primary route of excretion.


Assuntos
Androstenóis/administração & dosagem , Androstenóis/farmacocinética , Saúde , Administração Oral , Adolescente , Adulto , Androstenos , Androstenóis/sangue , Androstenóis/química , Radioisótopos de Carbono , Relação Dose-Resposta a Droga , Humanos , Masculino , Redes e Vias Metabólicas , Metabolômica , Pessoa de Meia-Idade , Radioatividade , Fatores de Tempo , Adulto Jovem
11.
Biomed Chromatogr ; 27(2): 203-7, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22763809

RESUMO

A novel, simple, specific, sensitive and reproducible high-performance liquid chromatography (HPLC) assay method has been developed and validated for the estimation of abiraterone (ART) in rat plasma. The analytical procedure involves extraction of ART and diclofenac (internal standard, IS) from rat plasma with a simple liquid-liquid extraction process. The chromatographic analysis was performed on a Waters Alliance system with a Betasil C(18) column maintained at ambient room temperature and an isocratic mobile phase [acetonitrile-water-10 mm potassium dihydrogen phosphate (pH 3.0), 55:5:40, v/v/v] at a flow rate of 1.00 mL/min with a total run time of 10 min. The eluate was monitored using an UV detector set at 255 nm. Method validation was performed as per FDA guidelines and the results met the acceptance criteria. The calibration curve was linear over a concentration range of 93.4-3251 ng/mL (r(2) = 0.997). The intra- and inter-day precisions were 0.56-4.98 and 3.03-7.18, respectively, in rat plasma. The validated HPLC method was successfully applied to a pharmacokinetic study of ART in rats.


Assuntos
Androstenóis/sangue , Cromatografia de Fase Reversa/métodos , Androstenos , Androstenóis/química , Androstenóis/farmacocinética , Animais , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Modelos Lineares , Extração Líquido-Líquido , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta
12.
Biomed Chromatogr ; 26(6): 761-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22002259

RESUMO

A highly sensitive, rapid assay method has been developed and validated for the estimation of abiraterone (ART) in rat and human plasma with liquid chromatography coupled to tandem mass spectrometry and electrospray ionization in the positive-ion mode. The assay procedure involves extraction of ART and phenacetin (internal standard, IS) from rat and human plasma with a simple protein precipitation extraction process. Chromatographic separation was achieved using an isocratic mobile (10 mm ammonium acetate:acetonitrile, 10:90, v/v) at a flow-rate of 0.70 mL/min on an Atlantis dC(18) column maintained at 40 °C with a total run time of 3.5 min. The MS/MS ion transitions monitored were 350.3 → 156.0 for ART and 180.2 → 110.1 for IS. Method validation was performed as per FDA guidelines and the results met the acceptance criteria. The lower limit of quantitation achieved was 0.20 ng/mL and the linearity range extended from 0.20 to 201 ng/mL. The intra- and inter-day precisions were in the ranges 2.39-10.4 and 4.84-9.53% in rat plasma and 3.82-10.8 and 6.97-8.94% in human plasma.


Assuntos
Androstenóis/sangue , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Androstenos , Androstenóis/química , Androstenóis/farmacocinética , Animais , Estabilidade de Medicamentos , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray/métodos
13.
Obesity (Silver Spring) ; 19(4): 806-11, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20847733

RESUMO

Metabolic syndrome is marked by perturbed glucocorticoid (GC) signaling, systemic inflammation, and altered immune status. Dehydroepiandrosterone (DHEA), a major circulating adrenal steroid and dietary supplement, demonstrates antiobesity, anti-inflammatory, GC-opposing and immune-modulating activity when administered to rodents. However, plasma DHEA levels failed to correlate with metabolic syndrome and oral replacement therapy provided only mild benefits to patients. Androstene-3ß,7ß,17ß-triol (ß-AET) an anti-inflammatory metabolite of DHEA, also exhibits GC-opposing and immune-modulating activity when administered to rodents. We hypothesized a role for ß-AET in obesity. We now report that plasma levels of ß-AET positively correlate with BMI in healthy men and women. Together with previous studies, the observations reported here may suggest a compensatory role for ß-AET in preventing the development of metabolic syndrome. The ß-AET structural core may provide the basis for novel pharmaceuticals to treat this disease.


Assuntos
Androstenóis/sangue , Anti-Inflamatórios/sangue , Fármacos Antiobesidade/sangue , Síndrome Metabólica/metabolismo , Obesidade/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Desidroepiandrosterona/sangue , Desidroepiandrosterona/uso terapêutico , Feminino , Glucocorticoides/antagonistas & inibidores , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Esteroides/farmacologia , Adulto Jovem
14.
Neuro Endocrinol Lett ; 30(3): 368-72, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19855361

RESUMO

OBJECTIVE: Dehydroepiandrosterone is a long established neuroactive steroid. Some authors documented that 7-oxygenated derivatives of this steroid may be responsive at least by part for its physiological activity. METHODS: In the ventricular cerebrospinal fluid obtained from 15 patients with hydrocephalus (8 postmenopausal women and 7 men) potentially neuroactive steroid 7-oxygenated derivatives of dehydroepiandrosterone were quantified using gas chromatography/mass spectrometry. RESULTS: Besides free dehydroepiandrosterone 7-oxygenated steroids such as 7alpha- and 7beta-hydroxy-dehydroepiandrosterone, 5-androstene-3beta,7alpha,17beta-triol and 5-androstene-3beta,7beta,17beta-triol in picomolar concentration in serum and cerebrospinal fluid were found. CONCLUSION: Dehydroepiandrosterone and its 7-oxygenated derivatives are present in ventricular cerebrospinal fluid in concentration 2 -100 times lower than in serum.


Assuntos
Androstenóis/líquido cefalorraquidiano , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/líquido cefalorraquidiano , Hidrocefalia/líquido cefalorraquidiano , Adulto , Androstenóis/sangue , Desidroepiandrosterona/sangue , Feminino , Humanos , Hidrocefalia/sangue , Hidrocefalia/cirurgia , Masculino , Espectrometria de Massas
15.
Reprod Sci ; 14(2): 151-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17636226

RESUMO

Unlike estrogens plus progestagens, tibolone, a selective tissue estrogenic activity regulator, does not increase breast tenderness and mammographic density. To elucidate this, serum and breast levels of tibolone and estrogenic metabolites are measured. Postmenopausal women (n = 102) with early-stage, ER(+ve), primary breast cancer received tibolone or placebo for 14 days in an exploratory, double-blind, randomized trial (STEM carcinoma tissue). Baseline and presurgery sera were collected; tumor tissues were obtained at surgery. E(1) (estrone), E(2) (estradiol), E(1)S (estrone-sulfate), tibolone-its nonsulfated, monosulfated, and disulfated 3-hydroxymetabolites-and Delta(4)-tibolone were measured by validated gas chromatography and mass spectrometry and liquid chromatography with tandem mass spectrometry assays. More than 12 hours after the final dose, serum E(1), E(2), and E(1)S levels were unchanged with placebo, whereas tibolone significantly increased E(1)S and the E(1)S/(E(1) + E(2)) ratio. In tumors, E(1) and E(2) levels were higher than in serum, and E(1)S levels were lower, with placebo and tibolone administration. The percentage of E(1)S was about 90% in serum and 16% in tissue. Tibolone did not affect tissue levels of endogenous estrogens. Serum levels of estrogenic 3alpha- and 3beta-hydroxytibolone, progestagenic/androgenic Delta(4)-tibolone, and monosulfate metabolites were low. Serum 3alphaS,17betaS-tibolone and 3 betaS,17betaS-tibolone levels were 250 and 52 ng/mL, respectively. Tumor levels of 3alpha- and 3beta-hydroxytibolone and Delta(4)-tibolone were higher than in serum, but disulfate levels were lower. The percentage of sulfated tibolone metabolites was 99% in serum and 96% in tumor. Serum metabolite patterns of estradiol and tibolone are different from those in tissues and are compatible with neutral effects of tibolone on breast Ki67 expression.


Assuntos
Neoplasias da Mama/metabolismo , Mama/metabolismo , Estrenos/metabolismo , Norpregnenos/metabolismo , Moduladores Seletivos de Receptor Estrogênico/metabolismo , Idoso , Androstenóis/sangue , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Cromatografia Líquida , Método Duplo-Cego , Estradiol/sangue , Estradiol/metabolismo , Estrenos/sangue , Estrona/análogos & derivados , Estrona/sangue , Estrona/metabolismo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Norpregnenos/análise , Norpregnenos/sangue , Norpregnenos/uso terapêutico , Pós-Menopausa/sangue , Pós-Menopausa/metabolismo , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Espectrometria de Massas em Tandem , Distribuição Tecidual
16.
Artigo em Inglês | MEDLINE | ID: mdl-16809076

RESUMO

A sensitive and selective LC-MS/MS method has been developed and validated for the quantification of abiraterone acetate and its metabolite, abiraterone (an androgen biosynthesis inhibitor) in human plasma. Analytes were extracted by SPE with cation mixed-mode polymer cartridges. Chromatography was performed on a Luna C5 5 microm, 50 mm x 2.1 mm i.d. column, using a mobile phase of 2% propan-2-ol in acetonitrile and 10mM ammonium acetate. The assay was linear from 5 to 500 nM (r(2)=0.998). The intra- and inter-day coefficients of variation were <13.9% for both analytes. This method will be applied to a clinical trial investigating the pharmacokinetics of abiraterone acetate and abiraterone in patients with prostate cancer.


Assuntos
Androstenóis/sangue , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Androstenos , Estabilidade de Medicamentos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Int J Gynecol Cancer ; 16 Suppl 1: 368-74, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16515626

RESUMO

The clinicopathologic findings of the third case of androgenic adult granulosa cell tumor in patients younger than 15 years was presented and discussed in the light of the literature. A patient complaining of secondary amenorrhea and hirsutism with elevated levels of plasma total testosterone, dehydroepiandrosterone sulfate, free androgen index and serum inhibin A, and a left ovarian septated, cystic mass was admitted to the hospital. The inhibin A level was within normal levels in the first month postoperatively. Inhibin A could be a tumor marker of utmost importance particularly in patients with androgenic or hyperestrogenic symptoms, especially in cases where benign criteria are abundant such as young age, nonincreased levels of classic tumor markers, and ultrasonographic appearance without any suspicion of malignancy.


Assuntos
Biomarcadores Tumorais/sangue , Tumor de Células da Granulosa/diagnóstico , Inibinas/sangue , Neoplasias Ovarianas/diagnóstico , Adolescente , Amenorreia/etiologia , Androgênios/sangue , Androstenóis/sangue , Feminino , Tumor de Células da Granulosa/sangue , Tumor de Células da Granulosa/complicações , Tumor de Células da Granulosa/cirurgia , Procedimentos Cirúrgicos em Ginecologia , Hirsutismo/etiologia , Humanos , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/cirurgia
18.
Psychopharmacology (Berl) ; 186(3): 451-61, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16341848

RESUMO

BACKGROUND: GABAA receptors are an important site of action of endogenous neurosteroids and an important mediator of several behavioral effects of alcohol. This study examined the effects of alcohol on plasma steroid hormone concentrations on the hypothesis that the endocrine effects mediate some of the subjective effects of alcohol. METHODS: Thirty-two healthy subjects (17 men) with no history of a substance use disorder participated in this human laboratory study. All subjects consumed three standard drinks of grain alcohol. Subjective measures and blood samples for steroid concentrations were collected at baseline and 40 min after alcohol consumption. RESULTS: Alcohol increased self-reported stimulation, alcohol liking, and desire for more alcohol. Alcohol also increased pregnenolone (PREG) and dehydroepiandrosterone (DHEA) concentrations, while it decreased progesterone (PROG) and allopregnanolone (ALLO) concentrations, as well as ALLO/PREG and PROG/PREG ratios. In men, the change in PREG concentration was significantly correlated with alcohol liking, while the alcohol-induced change in ALLO concentration correlated significantly with both alcohol liking and desire for more alcohol. DISCUSSION: These findings provide preliminary support for the hypothesis that endogenous neurosteroids mediate some of the subjective effects of alcohol. Efforts to replicate these findings should aim to specify more clearly the nature and time course of the effects.


Assuntos
Androstenóis/sangue , Etanol/farmacologia , Pregnanos/sangue , Adulto , Consumo de Bebidas Alcoólicas/sangue , Consumo de Bebidas Alcoólicas/psicologia , Estimulantes do Sistema Nervoso Central/farmacologia , Feminino , Humanos , Hipnóticos e Sedativos/farmacologia , Masculino
19.
Neurosci Behav Physiol ; 35(9): 931-5, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16270175

RESUMO

The effects of daily immobilization stress applied to female rats on days 15 to 18 of pregnancy on the activity of the enzyme 5 alpha-reductase (isoform I), involved in the synthesis of brain neurosteroids were studied in male offspring. The results demonstrated a decrease in enzyme activity in the cerebral cortex and hypothalamus of male fetuses one day after the last session of stress, while enzyme activity was elevated in the cortex of neonates. Increases in 5 alpha-reductase activity in the cortex, hippocampus, and hypothalamus were also seen in prenatally stressed males on day 5 of life. There were reductions in plasma testosterone and progesterone levels in experimental animals on day 19 of embryonic life and in neonatal rats, the blood progesterone level in prenatally stressed rats remaining decreased at age five days. The possible involvement of neurosteroids in the actions of prenatal stress on sexual differentiation of the brain is discussed.


Assuntos
Androstenóis/sangue , Encéfalo/enzimologia , Colestenona 5 alfa-Redutase/metabolismo , Período Crítico Psicológico , Efeitos Tardios da Exposição Pré-Natal , Diferenciação Sexual/fisiologia , Estresse Fisiológico/enzimologia , Animais , Animais Recém-Nascidos , Encéfalo/anatomia & histologia , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Embrião de Mamíferos , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Masculino , Gravidez , Ratos , Ratos Wistar , Restrição Física/métodos
20.
Cancer Epidemiol Biomarkers Prev ; 13(6): 936-43, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15184249

RESUMO

OBJECTIVE: Light exposure during night work suppresses melatonin production, and night work has been associated with an increased cancer risk. There is little information, however, about the interrelationships of night work, urinary melatonin levels, and levels of plasma steroid hormones in women. METHOD: We examined the reproducibility of morning urinary measurements of 6-sulfatoxymelatonin over a 3-year period in 80 premenopausal women. We assessed correlations between average urinary melatonin and plasma steroid hormone levels and evaluated potential associations between night work and hormone levels, using current and long-term shift work information from two large, prospective cohorts, the Nurses' Health Study cohorts. RESULTS: The intraclass correlation for creatinine-adjusted 6-sulfatoxymelatonin was 0.72 (95% confidence interval, 0.65, 0.82). We found significantly increased levels of estradiol after longer durations of night work (geometric mean levels of estradiol, 8.8 pg/mL for women who never worked night shifts versus 10.1 pg/mL for women who worked 15 or more years of night shifts; P for trend = 0.03). We observed a significant inverse association between increasing number of nights worked within the 2 weeks preceding urine collection and urinary melatonin levels (r = -0.30, P = 0.008), but no association of recent night work with estradiol (r = 0.10, P = 0.41). CONCLUSION: A single morning urinary melatonin measurement is a reasonable marker for long-term melatonin levels among premenopausal women. Women who work on rotating night shifts seem to experience changes in hormone levels that may be associated with the increased cancer risk observed among night-shift workers.


Assuntos
Biomarcadores , Estrona/análogos & derivados , Hormônios/sangue , Luz/efeitos adversos , Melatonina/análogos & derivados , Melatonina/urina , Esteroides/sangue , Tolerância ao Trabalho Programado/fisiologia , Adulto , Androstenodiona/sangue , Androstenóis/sangue , Disponibilidade Biológica , Biomarcadores/sangue , Biomarcadores/urina , Índice de Massa Corporal , Neoplasias da Mama/metabolismo , Estudos de Coortes , Creatinina/sangue , Desidroepiandrosterona/sangue , Estradiol/sangue , Estrona/sangue , Feminino , Humanos , Melatonina/antagonistas & inibidores , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros/estatística & dados numéricos , Prolactina/sangue , Reprodutibilidade dos Testes , Fatores de Risco , Manejo de Espécimes/métodos , Manejo de Espécimes/normas
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