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1.
Anal Bioanal Chem ; 413(22): 5655-5667, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34142201

RESUMO

In order to detect the misuse of testosterone (T), urinary steroid concentrations and concentration ratios are quantified and monitored in a longitudinal manner to enable the identification of samples exhibiting atypical test results. These suspicious samples are then forwarded to isotope ratio mass spectrometry (IRMS)-based methods for confirmation. Especially concentration ratios like T over epitestosterone (E) or 5α-androstanediol over E proved to be valuable markers. Unfortunately, depending on the UGT2B17 genotype and/or the gender of the athlete, these markers may fail to provide evidence for T administrations when focusing exclusively on urine samples. In recent years, the potential of plasma steroids has been investigated and were found to be suitable to detect T administrations especially in female volunteers. A current drawback of this approach is the missing possibility to confirm that elevated steroid concentrations are solely derived from an administration of T and cannot be attributed to confounding factors. Therefore, an IRMS method for plasma steroids was developed and validated taking into account the comparably limited sample volume. As endogenous reference compounds, unconjugated cholesterol and dehydroepiandrosterone sulfate were found suitable, while androsterone and epiandrosterone (both sulfo-conjugated) were chosen as target analytes. The developed method is based on multi-dimensional gas chromatography coupled to IRMS in order to optimize the overall assay sensitivity. The approach was validated, and a reference population encompassing n = 65 males and females was investigated to calculate population-based thresholds. As proof-of-concept, samples from volunteers receiving T replacement therapies and excretion study samples were investigated.


Assuntos
Isótopos de Carbono/análise , Congêneres da Testosterona/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Terapia de Reposição Hormonal , Humanos , Limite de Detecção , Masculino , Estudo de Prova de Conceito , Valores de Referência , Testosterona/administração & dosagem , Congêneres da Testosterona/normas
2.
J Chromatogr A ; 1628: 461445, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822984

RESUMO

Anabolic androgenic steroids (AAS) have been the most commonly abused substances taken by not only professional sportsmen but also recreational bodybuilders. The detection of micro-dose testosterone (T) misuse is particularly challenging as it possesses pseudo-endogenous origin and is sometimes impossible to be identified in urine samples. Dried blood (DB) obtained by finger pricking has been proven to be an alternative matrix for better correlating to physiological responses. Moreover, the introduction of the volumetric absorptive microsampling (VAMS) technology allows overcoming some major limitations of spotting blood onto a filter paper card. In this work, a fast and sensitive GC-MS/MS method was developed and validated for the quantification of AAS in DB collected by means of VAMS. T and the eight top abused synthetic AAS, namely nandrolone, boldenone, mesterolone, drostanolone, metenolone, metandienone, oxandrolone, and dehydrochloromethyl T were selected as the target analytes. The method based on VAMS exhibited good precision, accuracy as well as stability, and superior extraction recoveries over the punched DB spots reported in the literature. The chromatographic separation was achieved within 6.4 min and the detection limit is as little as 50 fg (i.e. able to detect 0.10 ng mL-1 in 20 µL of DB). Confirmed by forty real blood samples, the Deming regression and Bland-Altman analysis revealed that the VAMS DB could be employed for quantifying blood T level in agreement with using the serum specimen. The feasibility of the method was then successfully proven by the analysis of samples collected from a three-arm T administration trial. Our results highlighted that DB total T was a sensitive indicator for identifying transdermal micro-dosing of T. In the groups of receiving T gel administration, T concentrations could rise up to ten times higher than the baseline at 9 h after the application. As a future step, this approach is being expanded to a large cohort screening of bodybuilders at gym and ultimately may allow universal applications on monitoring sports drug misuse.


Assuntos
Androgênios/sangue , Teste em Amostras de Sangue Seco/métodos , Monitoramento de Medicamentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas em Tandem , Congêneres da Testosterona/sangue , Testosterona/análise , Humanos
3.
J Steroid Biochem Mol Biol ; 174: 242-256, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28982631

RESUMO

Dutasteride is a 5alpha-reductase inhibitor in clinical use to treat endocrine conditions. The present study investigated the neuroprotective mechanisms of action of dutasteride in intact and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-lesioned mice using a low dose of MPTP not affecting motor activity modeling early stages of Parkinson's disease (PD). We hypothesized that dutasteride neuroprotection is due to altered steroids levels. Dutasteride pre-treatment prevented loss of striatal dopamine (DA) and its metabolite DOPAC. Dutasteride decreased effects of MPTP on striatal dopamine transporter (DAT), vesicular monoamine transporter 2 (VMAT2) and D2 DA receptor specific binding while D1 receptor specific binding remained unchanged. Dutasteride enhanced DAT specific binding and the glycosylated form of DAT in intact mice. MPTP-lesioned mice had plasma and brain testosterone and dihydrotestosterone levels lower than control mice whereas progesterone and its metabolites (dihydroprogesterone, isopregnanolone and tetrahydroprogesterone) pathway showed increases. Dutasteride treatment by inhibiting transformation of progesterone and testosterone to its metabolites elevated plasma and brain concentrations of testosterone compared to MPTP mice and decreased DHT levels in intact mice. Plasma and brain estradiol levels were low and remained unchanged by MPTP and/or dutasteride treatment. Dutasteride treatment did not affect striatal phosphorylation of Akt and its downstream substrate GSK3ß as well as phosphorylation of ERK1/2 in intact and MPTP lesioned MPTP mice. Striatal glial fibrillary acidic protein (GFAP) levels were markedly elevated in MPTP compared to control mice and dutasteride reduced GFAP levels in MPTP mice. Treatment with dutasteride post-lesion left unchanged striatal DA levels. These results suggest dutasteride as promising drug for PD neuroprotection.


Assuntos
Inibidores de 5-alfa Redutase/farmacologia , Encéfalo/efeitos dos fármacos , Dutasterida/farmacologia , Intoxicação por MPTP/metabolismo , Fármacos Neuroprotetores/farmacologia , Inibidores de 5-alfa Redutase/uso terapêutico , Androgênios/sangue , Androgênios/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/metabolismo , Dopamina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Dutasterida/uso terapêutico , Proteína Glial Fibrilar Ácida/metabolismo , Intoxicação por MPTP/tratamento farmacológico , Intoxicação por MPTP/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/uso terapêutico , Desempenho Psicomotor/efeitos dos fármacos , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Congêneres da Testosterona/sangue , Congêneres da Testosterona/metabolismo , Proteínas Vesiculares de Transporte de Monoamina/metabolismo
4.
Endocr Relat Cancer ; 24(8): 393-404, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28663228

RESUMO

Neoadjuvant androgen deprivation therapy (NADT) is one strategy for the treatment of early-stage prostate cancer; however, the long-term outcomes of NADT with radical prostatectomy including biochemical failure-free survival are not promising. One proposed mechanism is incomplete androgen ablation. In this study, we aimed to evaluate the efficiency of serum hydroxy-androgen suppression in patients with localized high-risk prostate cancer under NADT (leuprolide acetate plus abiraterone acetate and prednisone) and interrogate the primary sources of circulating hydroxy-androgens using our recently described stable isotope dilution liquid chromatography mass spectrometric method. For the first time, three androgen diols including 5-androstene-3ß,17ß-diol (5-adiol), 5α-androstane-3α,17ß-diol (3α-adiol), 5α-androstane-3ß,17ß-diol (3ß-adiol), the glucuronide or sulfate conjugate of 5-adiol and 3α-adiol were measured and observed to be dramatically reduced after NADT. By comparing patients that took leuprolide acetate alone vs leuprolide acetate plus abiraterone acetate and prednisone, we were able to distinguish the primary sources of these androgens and their conjugates as being of either testicular or adrenal in origin. We find that testosterone, 5α-dihydrotestosterone (DHT), 3α-adiol and 3ß-adiol were predominately of testicular origin. By contrast, dehydroepiandrosterone (DHEA), epi-androsterone (epi-AST) and their conjugates, 5-adiol sulfate and glucuronide were predominately of adrenal origin. Our findings also show that NADT failed to completely suppress DHEA-sulfate levels and that two unappreciated sources of intratumoral androgens that were not suppressed by leuprolide acetate alone were 5-adiol-sulfate and epi-AST-sulfate of adrenal origin.


Assuntos
Acetato de Abiraterona/uso terapêutico , Androgênios/sangue , Antineoplásicos Hormonais/uso terapêutico , Leuprolida/uso terapêutico , Prednisona/uso terapêutico , Neoplasias da Próstata/sangue , Neoplasias da Próstata/tratamento farmacológico , Glândulas Suprarrenais/metabolismo , Glucuronídeos/sangue , Humanos , Masculino , Terapia Neoadjuvante , Sulfatos/sangue , Testículo/metabolismo , Testosterona/sangue , Congêneres da Testosterona/sangue
5.
Fertil Steril ; 107(4): 1012-1022.e2, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28366409

RESUMO

OBJECTIVE: To identify reproductive, lifestyle, hormonal, and other correlates of circulating antimüllerian hormone (AMH) concentrations in mostly late premenopausal women. DESIGN: Cross-sectional study. SETTING: Not applicable. PATIENT(S): A total of 671 premenopausal women not known to have cancer. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Concentrations of AMH were measured in a single laboratory using the picoAMH ELISA. Multivariable-adjusted median (and interquartile range) AMH concentrations were calculated using quantile regression for several potential correlates. RESULT(S): Older women had significantly lower AMH concentrations (≥40 [n = 444] vs. <35 years [n = 64], multivariable-adjusted median 0.73 ng/mL vs. 2.52 ng/mL). Concentrations of AMH were also significantly lower among women with earlier age at menarche (<12 [n = 96] vs. ≥14 years [n = 200]: 0.90 ng/mL vs. 1.12 ng/mL) and among current users of oral contraceptives (n = 27) compared with never or former users (n = 468) (0.36 ng/mL vs. 1.15 ng/mL). Race, body mass index, education, height, smoking status, parity, and menstrual cycle phase were not significantly associated with AMH concentrations. There were no significant associations between AMH concentrations and androgen or sex hormone-binding globulin concentrations or with factors related to blood collection (e.g., sample type, time, season, and year of blood collection). CONCLUSION(S): Among premenopausal women, lower AMH concentrations are associated with older age, a younger age at menarche, and currently using oral contraceptives, suggesting these factors are related to a lower number or decreased secretory activity of ovarian follicles.


Assuntos
Hormônio Antimülleriano/sangue , Estilo de Vida , Reserva Ovariana , Pré-Menopausa/sangue , Adulto , Fatores Etários , Ásia , Biomarcadores/sangue , Anticoncepcionais Orais Hormonais/uso terapêutico , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Europa (Continente) , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Globulina de Ligação a Hormônio Sexual/análise , Congêneres da Testosterona/sangue , Estados Unidos , Adulto Jovem
6.
J Vet Diagn Invest ; 29(2): 143-147, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28176608

RESUMO

Platelet-rich plasma has been studied extensively in dogs, but validation of enzyme-linked immunosorbent assays (ELISAs) for quantifying anabolic growth factors and inflammatory cytokines in canine plasma prepared with citrate-based anticoagulants is not available. We performed a validation of commercial ELISAs for transforming growth factor-beta 1 (TGF-ß1), platelet-derived growth factor-BB (PDGF-BB), vascular endothelial growth factor (VEGF), tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1ß) for use with canine plasma prepared with acid-citrate-dextrose, solution A (ACD-A). Platelet-poor plasma (PPP) anticoagulated with ACD-A as well as PPP anticoagulated with ACD-A and spiked with the relevant canine recombinant proteins were evaluated with each ELISA to calculate the efficiency of spike recovery. Replicates of the spiked PPP were also assessed in 2 additional assays to quantify intra-assay and interassay precision. The efficiency of spike recovery was within 75-125% of the expected concentration for the TGF-ß1, PDGF-BB, and VEGF ELISAs. The intra- and interassay variability were <25% for the TGF-ß1, PDGF-BB, VEGF, and TNF-α ELISAs. The TGF-ß1, PDGF-BB, and VEGF ELISAs demonstrate acceptable efficiency of spike recovery and intra- and interassay variability, whereas the TNF-α and IL-1ß ELISAs did not meet industry standards of performance with ACD-A anticoagulated canine plasma.


Assuntos
Citocinas/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Plasma Rico em Plaquetas/química , Animais , Anticoagulantes , Becaplermina , Cães , Proteínas Proto-Oncogênicas c-sis/sangue , Reprodutibilidade dos Testes , Congêneres da Testosterona/sangue , Fator de Crescimento Transformador beta1/sangue , Fator de Necrose Tumoral alfa/sangue , Fator A de Crescimento do Endotélio Vascular/sangue
7.
Toxicology ; 376: 75-82, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27234315

RESUMO

In recent years it was verified there are an alarming growing number of teenagers and young adults using a combination of dietary supplements (DS) anabolic androgenic steroids (AAS) and drugs of abuse. This practice is used to improve physical fitness and appearance, may cause serious side effects. This article shows the alterations in the hematological and renal function parameters associate with these substances in 40 athletes. This research involved three steps: 1-the administration of a self-completion questionnaire ; 2-the assessment of hematological and biochemical parameters of renal function and; 3-toxicological urinalysis. Hematological and biochemical tests were conducted in an accredited laboratory and the toxicological urinalysis was validated in our laboratory using liquid-liquid extraction (LLE) and gas chromatography-mass spectrometry (GC-MS). The testosterone levels in the participants who consumed steroids increased 20-60% and alterations in serum creatinine, urea and uric reached values of up to 1.9; 60.6 and 7.5mg/dL, respectively. The toxicological urinalysis supports self-reports confirming the use of AAS and recreational drugs, putting at risk the health of those athletes increasing the chances of kidney diseases.


Assuntos
Atletas , Suplementos Nutricionais , Drogas Ilícitas/sangue , Drogas Ilícitas/urina , Congêneres da Testosterona/sangue , Congêneres da Testosterona/urina , Adulto , Compreensão , Dopagem Esportivo/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Inquéritos e Questionários , Urinálise/métodos , Adulto Jovem
8.
J Steroid Biochem Mol Biol ; 158: 82-89, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26804970

RESUMO

Testosterone has in recent years been proven essential for normal growth and maturation of small growing follicles. Concomitantly, low functional ovarian reserve (LFOR), characterized by a small growing follicle pool, has been associated with low testosterone levels, which can be of ovarian and/or adrenal origin. In this study we, therefore, investigated whether peripheral sex steroid precursors and testosterone levels potentially reflect on adrenal function. In a retrospective cohort study of 355 consecutive infertile women, who presented to an academically affiliated fertility center in New York City, we investigated in a series of statistical models whether low peripheral sex steroid precursors and testosterone are associated with peripheral cortisol (C) levels, reflecting adrenal function. To determine potential correlations, we investigated the dehydroepiandrosterone (DHEA), DHEA sulfate (DHEAS), androstenedione (AD), total testosterone (TT), free testosterone (FT); sex hormone binding globulin (SHBG), anti-Müllerian hormone (AMH), thyroid stimulating hormone (TSH) and C in a series of multivariate and logistic regression analyses, utilizing C either as a continuous variable or with cut off <5.0µg/dL, and TT only as a continuous variable. Practically all models demonstrated significant predictability of peripheral sex hormone precursors for C levels, with DHEA demonstrating the strongest and most consistent predictability as an individual parameter and as part of the DHEAS/DHEA ratio. We conclude that in infertile women peripheral sex hormone precursors, especially DHEA, reflect C levels and, therefore, adrenal function. In infertile women, at all ages low levels of sex hormone precursors, therefore, should be considered indications for further adrenal assessments.


Assuntos
Androgênios/sangue , Hidrocortisona/sangue , Infertilidade Feminina/sangue , Adulto , Hormônio Antimülleriano/sangue , Feminino , Humanos , Globulina de Ligação a Hormônio Sexual/análise , Congêneres da Testosterona/sangue , Tireotropina/sangue
9.
J Lipid Res ; 56(9): 1843-51, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26239050

RESUMO

Steroids are primarily present in human fluids in their sulfated forms. Profiling of these compounds is important from both diagnostic and physiological points of view. Here, we present a novel method for the quantification of 11 intact steroid sulfates in human serum by LC-MS/MS. The compounds analyzed in our method, some of which are quantified for the first time in blood, include cholesterol sulfate, pregnenolone sulfate, 17-hydroxy-pregnenolone sulfate, 16-α-hydroxy-dehydroepiandrosterone sulfate, dehydroepiandrosterone sulfate, androstenediol sulfate, androsterone sulfate, epiandrosterone sulfate, testosterone sulfate, epitestosterone sulfate, and dihydrotestosterone sulfate. The assay was conceived to quantify sulfated steroids in a broad range of concentrations, requiring only 300 µl of serum. The method has been validated and its performance was studied at three quality controls, selected for each compound according to its physiological concentration. The assay showed good linearity (R(2) > 0.99) and recovery for all the compounds, with limits of quantification ranging between 1 and 80 ng/ml. Averaged intra-day and between-day precisions (coefficient of variation) and accuracies (relative errors) were below 10%. The method has been successfully applied to study the sulfated steroidome in diseases such as steroid sulfatase deficiency, proving its diagnostic value. This is, to our best knowledge, the most comprehensive method available for the quantification of sulfated steroids in human blood.


Assuntos
Ésteres do Colesterol/sangue , Progestinas/sangue , Sulfatos/sangue , Congêneres da Testosterona/sangue , Cromatografia Líquida , Humanos , Espectrometria de Massas em Tandem
10.
Prostate ; 75(12): 1255-63, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25939591

RESUMO

BACKGROUND: Resveratrol is a naturally occurring polyphenol with purported inhibitory effects on prostate growth and cancer development. A number of studies have demonstrated that resveratrol reduces prostate growth in animal models and reduces prostate cell growth in vitro. Based on these pre-clinical findings, interest in resveratrol is increasing in relation to the management of benign prostate hyperplasia (BPH) and prostate cancer. So far, no human trials have evaluated the effects of resveratrol on circulating androgens, prostate size, or biochemical markers of prostate size. METHODS: In a randomized placebo controlled clinical study using two doses of resveratrol (150 mg or 1,000 mg resveratrol daily) for 4 months, we evaluated the effects on prostate size, prostate specific antigen (PSA) and sex steroid hormones in 66 middle-aged men suffering from the metabolic syndrome(MetS). RESULTS: At baseline, prostate size and PSA were positively correlated (R = 0.34, P < 0.007) as was prostate size and age (R = 0.37, P < 0.003). Prostate size did not correlate with testosterone, free testosterone, dihydrotestosterone (DHT), or any other androgen precursor at baseline. The highest dose of resveratrol lowered the serum level of androstenedione 24% (P = 0.052), dehydroepiandrosterone (DHEA) 41% (P < 0.01), and dehydroepiandrosterone-sulphate (DHEAS) 50% (p<0.001), compared to the control group. However, prostate size and levels of PSA, testosterone, free testosterone and DHT remained unchanged. CONCLUSION: In this population of middle-aged men suffering from MetS, high dose resveratrol (1,000 mg daily) administration for 4 months significantly lowered serum levels of the androgen precursors androstenedione, DHEA and DHEAS, whereas prostate size and circulating levels of PSA, testosterone, free testosterone, and dihydrotestosterone were unaffected. The present study suggests that resveratrol does not affect prostate volume in healthy middle-aged men as measured by PSA levels and CT acquired prostate volumes. Consequently, we find no support for the use of resveratrol in the treatment of benign prostate hyperplasia.


Assuntos
Androgênios/metabolismo , Antineoplásicos Fitogênicos/administração & dosagem , Biomarcadores Tumorais/sangue , Di-Hidrotestosterona/sangue , Antígeno Prostático Específico/sangue , Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Estilbenos/administração & dosagem , Congêneres da Testosterona/sangue , Testosterona/sangue , Idoso , Método Duplo-Cego , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Próstata/metabolismo , Neoplasias da Próstata/sangue , Análise de Regressão , Resveratrol
11.
Addiction ; 110(5): 823-31, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25598171

RESUMO

AIMS: To assess the frequency and severity of hypogonadal symptoms in male long-term anabolic-androgenic steroid (AAS) misusers who have discontinued AAS use. DESIGN: Cross-sectional, naturalistic. SETTING: Out-patient facility. PARTICIPANTS: Twenty-four male former long-term AAS users and 36 non-AAS-using weightlifters, recruited by advertisement in Massachusetts, USA. Five of the former users were currently receiving treatment with physiological testosterone replacement, leaving 19 untreated users for the numerical comparisons below. MEASUREMENTS: The Structured Clinical Interview for DSM-IV, questions regarding history of AAS use, physical examination, serum hormone determinations and the International Index of Erectile Function (IIEF). FINDINGS: Compared with the 36 non-AAS-using weightlifters, the 19 untreated former AAS users displayed significantly smaller testicular volumes [estimated difference, 95% confidence interval (CI) = 2.3 (0.1, 4.5) ml; P = 0.042] and lower serum testosterone levels [estimated difference: 95% CI = 131 (25, 227) dl; P = 0.009], with five users showing testosterone levels below 200 ng/dl despite abstinence from AAS for 3-26 months. Untreated former users also displayed significantly lower scores on the IIEF sexual desire subscale [estimated difference: 95% CI = 2.4 (1.3, 3.4) points on a 10-point scale; P < 0.001]. In the overall group of 24 treated plus untreated former users, seven (29%) had experienced major depressive episodes during AAS withdrawal; four of these had not experienced major depressive episodes at any other time. Two men (8%) had failed to regain normal libidinal or erectile function despite adequate replacement testosterone treatment. CONCLUSIONS: Among long-term anabolic-androgenic steroid misusers, anabolic-androgenic steroid-withdrawal hypogonadism appears to be common, frequently prolonged and associated with substantial morbidity.


Assuntos
Androgênios/intoxicação , Hipogonadismo/induzido quimicamente , Uso Indevido de Medicamentos sob Prescrição/efeitos adversos , Congêneres da Testosterona/intoxicação , Adolescente , Adulto , Androgênios/sangue , Estudos Transversais , Humanos , Hipogonadismo/sangue , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Testosterona/sangue , Congêneres da Testosterona/sangue , Levantamento de Peso , Adulto Jovem
13.
Endocrinology ; 154(9): 3410-22, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23766127

RESUMO

We recently created a mouse model displaying precocious Sertoli cell (SC) and spermatogenic development induced by SC-specific transgenic androgen receptor expression (TgSCAR). Here we reveal that TgSCAR regulates the development, function, and absolute number of Leydig cells (LCs). Total fetal and adult type LC numbers were reduced in postnatal and adult TgSCAR vs control testes, despite normal circulating LH levels. Normal LC to SC ratios found in TgSCAR testes indicate that SC androgen receptor (SCAR)-mediated activity confers a quorum-dependent relationship between total SC and LC numbers. TgSCAR enhanced LC differentiation, shown by elevated ratios of advanced to immature LC types, and reduced LC proliferation in postnatal TgSCAR vs control testes. Postnatal TgSCAR testes displayed up-regulated expression of coupled ligand-receptor transcripts (Amh-Amhr2, Dhh-Ptch1, Pdgfa-Pdgfra) for potential SCAR-stimulated paracrine pathways, which may coordinate LC differentiation. Neonatal TgSCAR testes displayed normal T and dihydrotestosterone levels despite differential changes to steroidogenic gene expression, with down-regulated Star, Cyp11a1, and Cyp17a1 expression contrasting with up-regulated Hsd3b1, Hsd17b3, and Srd5a1 expression. TgSCAR males also displayed elevated postnatal and normal adult serum testosterone levels, despite reduced LC numbers. Enhanced adult-type LC steroidogenic output was revealed by increased pubertal testicular T, dihydrotestosterone, 3α-diol and 3ß-diol levels per LC and up-regulated steroidogenic gene (Nr5a1, Lhr, Cyp11a1, Cyp17a1, Hsd3b6, Srd5a1) expression in pubertal or adult TgSCAR vs control males, suggesting regulatory mechanisms maintain androgen levels independently of absolute LC numbers. Our unique gain-of-function TgSCAR model has revealed that SCAR activity controls temporal LC differentiation, steroidogenic function, and population size.


Assuntos
Diferenciação Celular , Células Intersticiais do Testículo/citologia , Receptores Androgênicos/metabolismo , Células de Sertoli/metabolismo , Testículo/citologia , Congêneres da Testosterona/metabolismo , Animais , Animais Recém-Nascidos , Biomarcadores/metabolismo , Contagem de Células , Hemizigoto , Isoenzimas/biossíntese , Isoenzimas/genética , Isoenzimas/metabolismo , Células Intersticiais do Testículo/metabolismo , Ligantes , Masculino , Camundongos , Camundongos Transgênicos , Receptores Patched , Receptor Patched-1 , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/biossíntese , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores Androgênicos/biossíntese , Receptores Androgênicos/genética , Receptores de Superfície Celular/biossíntese , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Receptores de Peptídeos/biossíntese , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Células de Sertoli/citologia , Desenvolvimento Sexual , Testículo/crescimento & desenvolvimento , Testículo/metabolismo , Congêneres da Testosterona/sangue , Regulação para Cima
14.
Food Chem Toxicol ; 59: 261-71, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23774258

RESUMO

Ethylenethiourea (ETU) is the common metabolite of the widely used ethylenebisdithiocarbamate fungicides. It is identified as Endocrine Disruptor given its ability to interfere with thyroid hormone biosynthesis by inhibiting thyroid peroxidase activity. As far as we know, no studies have been performed to assess potential effects of ETU exposure at low dose levels, i.e. below the established LOAEL and NOAEL, during critical phases of development. Therefore, the aim of the present study was to verify the short- and long-term effects on thyroid function, reproduction and development of oral exposure to ETU levels comparable to and lower than LOAEL/NOAEL in rats. Sixty dams were treated daily by gavage during pregnancy and lactation with 0, 0.1, 0.3, 1.0 mg/kg bw per day of ETU. F1 generation was similarly treated from weaning to sexual maturity. Thyroid biomarkers were analyzed in dams and in offspring. Reproductive biomarkers were analyzed in F1 rats. For the first time this study has demonstrated reproductive toxicity and hypothyroidism at a lower than LOAEL dose exposure in pregnant dams and F1 generation. Our data suggest that even low doses of ETU can interfere with thyroid homeostasis and reproductive hormone profile if exposure starts in critical stages of development.


Assuntos
Disruptores Endócrinos/toxicidade , Etilenotioureia/toxicidade , Hipotireoidismo/induzido quimicamente , Infertilidade Feminina/induzido quimicamente , Infertilidade Masculina/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal , Glândula Tireoide/efeitos dos fármacos , Administração Oral , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Hipotireoidismo Congênito/induzido quimicamente , Hipotireoidismo Congênito/fisiopatologia , Relação Dose-Resposta a Droga , Disruptores Endócrinos/administração & dosagem , Congêneres do Estradiol/sangue , Etilenotioureia/administração & dosagem , Feminino , Fungicidas Industriais/metabolismo , Fungicidas Industriais/toxicidade , Hipotireoidismo/sangue , Hipotireoidismo/patologia , Hipotireoidismo/fisiopatologia , Infertilidade Feminina/sangue , Infertilidade Masculina/sangue , Lactação , Masculino , Resíduos de Praguicidas/toxicidade , Gravidez , Ratos , Ratos Sprague-Dawley , Congêneres da Testosterona/sangue , Glândula Tireoide/patologia , Glândula Tireoide/fisiopatologia
15.
J Clin Endocrinol Metab ; 98(7): 3058-67, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23780369

RESUMO

CONTEXT: Physiological transient imbalance typical of adolescence needs to be distinguished from hyperandrogenism-related dysfunction. The accurate determination of circulating androgens is the best indicator of hyperandrogenism. However, reliable reference intervals for adolescent and young women are not available. OBJECTIVE: The aim of the study was to define androgen reference intervals in young women and to analyze the impact of the menstrual phase and ovulation efficiency over the androgen profile as assessed by reliable liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique. PARTICIPANTS: Female high school students aged 16-19 years were included in the study. MAIN OUTCOME MEASURES: The study was performed on reference subjects properly selected among an unbiased population. Normal-weight, drug and disease free, eumenorrheic females with no signs of hyperandrogenism were included. The steroid hormone profile was determined by a validated in-house LC-MS/MS method. A statistical estimation of overall and menstrual phase-specific reference intervals was performed. A subgroup of anovulatory females was identified based on progesterone circulating levels. The impact of ovulation efficiency over hormonal profile was analyzed. RESULTS: A total of 159 females satisfied healthy criteria. Androgen levels did not vary according to menstrual phase, but a significantly higher upper reference limit was found for T in the luteal phase compared to the follicular phase. Higher T and androstenedione levels were observed in anovulatory compared to ovulatory females, paralleled by higher LH and FSH and lower 17-hydroxyprogesterone and 17ß-estradiol levels. CONCLUSIONS: This is the first study providing LC-MS/MS-based, menstrual phase-specific reference intervals for the circulating androgen profile in young females. We identified a subgroup of anovulatory healthy females characterized by androgen imbalance.


Assuntos
Androgênios/sangue , Anovulação/sangue , Ovulação/sangue , 17-alfa-Hidroxiprogesterona/sangue , 17-alfa-Hidroxiprogesterona/química , Adolescente , Algoritmos , Androgênios/química , Cromatografia Líquida de Alta Pressão , Estudos de Coortes , Estudos Transversais , Estradiol/sangue , Estradiol/química , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Itália , Hormônio Luteinizante/sangue , Ciclo Menstrual/sangue , Progesterona/sangue , Progesterona/química , Valores de Referência , Espectrometria de Massas em Tandem , Congêneres da Testosterona/sangue , Congêneres da Testosterona/química
16.
J Clin Endocrinol Metab ; 98(7): 3049-57, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23709655

RESUMO

CONTEXT: It is unknown whether intensive lifestyle modification (ILS) or metformin changes sex steroids among premenopausal women without a history of polycystic ovarian syndrome (PCOS). OBJECTIVES: We examined 1-year intervention impact on sex steroids (estradiol, testosterone, dehydroepiandrosterone, and androstenedione [A4]) and SHBG and differences by race/ethnicity. PARTICIPANTS: A subgroup of Diabetes Prevention Program participants who were premenopausal, not using estrogen, without a history of PCOS or irregular menses, and who reported non-Hispanic white (NHW), Hispanic, or African-American race/ethnicity (n = 301). INTERVENTIONS: Randomization arms were 1) ILS with the goals of weight reduction of 7% of initial weight and 150 minutes per week of moderate intensity exercise, 2) metformin 850 mg twice a day, or 3) placebo. RESULTS: Neither intervention changed sex steroids compared to placebo. ILS, but not metformin, increased median SHBG by 3.1 nmol/L (~11%) compared to decreases of 1.1 nmol/L in the placebo arm (P < .05). This comparison remained significant after adjustment for changes in covariates including waist circumference. However, associations with glucose were not significant. Median baseline A4 was lower in Hispanics compared to NHWs (5.7 nmol/L vs 6.5 nmol/L, P < .05) and increases in A4 were greater in Hispanics compared to NHWs (3.0 nmol/ vs 1.2 nmol/L, P < .05), and these differences did not differ significantly by intervention arm. No other racial/ethnic differences were significant. CONCLUSIONS: Among premenopausal glucose-intolerant women, no intervention changed sex steroids. ILS increased SHBG, although associations with glucose were not significant. SHBG and sex steroids were similar by race/ethnicity, with the possible exception of lower baseline A4 levels in Hispanics compared to NHWs.


Assuntos
Diabetes Mellitus/prevenção & controle , Dieta Redutora , Exercício Físico , Intolerância à Glucose/terapia , Sobrepeso/terapia , Globulina de Ligação a Hormônio Sexual/análise , Adulto , Negro ou Afro-Americano , Índice de Massa Corporal , Terapia Combinada , Diabetes Mellitus/etnologia , Diabetes Mellitus/etiologia , Estradiol/sangue , Feminino , Seguimentos , Intolerância à Glucose/sangue , Intolerância à Glucose/etnologia , Intolerância à Glucose/fisiopatologia , Hispânico ou Latino , Humanos , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Pessoa de Meia-Idade , Sobrepeso/sangue , Sobrepeso/etnologia , Sobrepeso/fisiopatologia , Pré-Menopausa , Congêneres da Testosterona/sangue , Estados Unidos , População Branca
17.
Hum Reprod ; 28(1): 224-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23019297

RESUMO

STUDY QUESTION: What is the final hormonal milieu of pre-ovulatory follicles of low-responder (LR) patients undergoing unstimulated cycles? SUMMARY ANSWER: Neither androgen secretion nor LH was impaired in pre-ovulatory follicles of LR women. WHAT IS KNOWN ALREADY: Therapies currently used to improve ovarian response in LR women have an impact on the final hormonal follicular milieu, and these changes are believed to be partially responsible for determining the success rate in these women. Surprisingly, as far as we know, there is no report of the final hormonal profile of LR women undergoing unstimulated cycles or evidence that follicular androgen secretion in LR women is impaired. STUDY DESIGN, SIZE AND DURATION: A prospective case-control study including 94 women, 36 normal controls and 58 LR patients (19 Young ≤ 35 years LR and 39 Aged >35 years LR) from 2009 to 2011. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Fifty-eight LR women were divided into two groups: Young LR (age ≤ 35; n = 19) and Aged LR (ALR; age >35; n = 39). The control group (group C) comprised 36 egg donors undergoing an unstimulated cycle in our IVF unit. Serum and follicular fluid hormonal concentrations for estradiol (E2), progesterone, testosterone and androstendione were measured. The spindle parameters of metaphase II oocytes generated from these groups were also analysed. MAIN RESULTS AND THE ROLE OF CHANCE: Pre-ovulatory follicles from LR patients had similar androgenic and LH concentrations to those observed in the control group. However, higher intrafollicular concentrations of FSH and progesterone were observed in ALR. Moreover, no differences were found for the spindle evaluation of oocytes between groups by the Oosight technology. LIMITATIONS, REASONS FOR CAUTION: The controls were younger and had a lower BMI than the LR women. The sample size available restricted statistical power. WIDER IMPLICATIONS OF THE FINDINGS: This study suggests that the problem with LR women is not the final pre-ovulatory follicular androgen concentration since this is similar to normal responders, but in the ability to respond to controlled ovarian stimulation protocols. Therefore, efforts should be focused on long-interval androgen priming to potentially increase the recruitment of small antral follicles rather than increasing the intraovarian androgen levels within the current cycle. STUDY FUNDING/COMPETING INTEREST: The present project has been supported by the R+D programme from the Generalitat Valenciana (Regional Valencian Government) IMPIVA MIDTF/2010/95. The authors have no conflict of interest to declare.


Assuntos
Líquido Folicular/metabolismo , Fase Folicular/sangue , Infertilidade Feminina/metabolismo , Hormônio Luteinizante/metabolismo , Folículo Ovariano/metabolismo , Congêneres da Testosterona/metabolismo , Adulto , Fatores Etários , Estudos de Casos e Controles , Resistência a Medicamentos , Feminino , Fármacos para a Fertilidade Feminina/farmacologia , Fertilização in vitro , Hormônio Foliculoestimulante/análise , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/metabolismo , Líquido Folicular/química , Fase Folicular/metabolismo , Humanos , Infertilidade Feminina/sangue , Infertilidade Feminina/patologia , Infertilidade Feminina/terapia , Hormônio Luteinizante/análise , Hormônio Luteinizante/sangue , Metáfase , Doação de Oócitos , Oócitos/patologia , Folículo Ovariano/efeitos dos fármacos , Indução da Ovulação , Progesterona/análise , Progesterona/sangue , Progesterona/metabolismo , Estudos Prospectivos , Fuso Acromático/patologia , Congêneres da Testosterona/análise , Congêneres da Testosterona/sangue
18.
J Biochem ; 153(1): 63-71, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23055536

RESUMO

The actual levels of steroid hormones in organs are vital for endocrine, reproductive and neuronal health and disorders. We developed an accurate method to determine the levels of steroid hormones and steroid conjugates in various organs by an efficient preparation using a solid-phase-extraction cartridge. Each steroid was identified by the precursor ion spectra using liquid chromatography-electrospray ionization time-of-flight mass spectrometry, and the respective steroids were quantitatively analysed in the selected reaction monitoring mode by liquid chromatograph-mass spectrometry/mass spectrometry (LC-MS/MS). The data showed that significant levels of testosterone, corticosterone and precursors of both hormones were detected in all organs except liver. The glucuronide conjugates of steroid hormones and the precursors were detected in all organs except liver, but sulfate conjugates of these steroids were observed only in the target organs of the hormones and kidney. Interestingly, these steroids and the conjugates were not observed in the liver except pregnenolone. In conclusion, an accurate determination of tissue steroids was developed using LC-MS analysis. Biosynthesis of steroid hormones from the precursors was estimated even in the target organs, and the delivery of these steroid conjugates was also suggested via the circulation without any significant hepatic participation.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Corticosterona/análise , Congêneres do Estradiol/análise , Espectrometria de Massas em Tandem/métodos , Congêneres da Testosterona/análise , Glândulas Suprarrenais/química , Glândulas Suprarrenais/metabolismo , Animais , Calibragem , Corticosterona/biossíntese , Corticosterona/sangue , Corticosterona/metabolismo , Congêneres do Estradiol/biossíntese , Congêneres do Estradiol/sangue , Congêneres do Estradiol/metabolismo , Glucuronídeos/química , Glucuronídeos/metabolismo , Rim/química , Rim/metabolismo , Limite de Detecção , Fígado/química , Fígado/metabolismo , Masculino , Especificidade de Órgãos , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Extração em Fase Sólida , Espectrometria de Massas por Ionização por Electrospray , Sulfatos/química , Sulfatos/metabolismo , Testículo/química , Testículo/metabolismo , Congêneres da Testosterona/biossíntese , Congêneres da Testosterona/sangue , Congêneres da Testosterona/metabolismo
19.
Gynecol Endocrinol ; 28(12): 965-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22780885

RESUMO

OBJECTIVE: To assess effects of vitamin D and Calcium (Ca) on hormonal and metabolic milieu of polycystic ovary syndrome (PCOS). DESIGN: Single arm open label trial. METHODS: Twelve overweight and vitamin D deficient women with PCOS underwent a 2 hour oral glucose tolerance testing at baseline and following 3-month supplementation with vitamin D (daily dose of 3533 IU, increased to 8533 IU after the first five participants) and 530 mg elemental Ca daily. MAIN OUTCOME MEASURES: Blood pressure (BP), plasma glucose, insulin, total testosterone (T) androstenedione (A), sex hormone binding globulin, lifestyle parameters were assessed at baseline and following 3-month intervention. Insulin resistance (IR) and area under the curve for glucose and insulin were computed; paired analyses were conducted. RESULTS: Improved serum 25OHD (p < 0.001) and reductions in total T (p = 0.036) and A (p = 0.090) levels were noted following 3-month supplementation, compared to baseline. Significant lowering in BP parameters was seen in participants with baseline BP ≥ 120/80 mmHg (n = 8) and in those with baseline serum 25OHD ≤20 ng/ml (n = 9). Parameters of glucose homeostasis and IR remained unchanged (p > 0.05). CONCLUSIONS: Androgen and BP profiles improved followed three month intervention, suggesting therapeutic implications of vitamin D and Ca in overweight and vitamin D deficient women with PCOS.


Assuntos
Cálcio da Dieta/uso terapêutico , Colecalciferol/uso terapêutico , Suplementos Nutricionais , Ergocalciferóis/uso terapêutico , Sobrepeso/complicações , Síndrome do Ovário Policístico/dietoterapia , Deficiência de Vitamina D/dietoterapia , 25-Hidroxivitamina D 2/sangue , Adulto , Índice de Massa Corporal , Calcifediol/sangue , Cálcio da Dieta/efeitos adversos , Colecalciferol/administração & dosagem , Colecalciferol/efeitos adversos , Colecalciferol/metabolismo , Estudos de Coortes , Suplementos Nutricionais/efeitos adversos , Ergocalciferóis/administração & dosagem , Ergocalciferóis/efeitos adversos , Ergocalciferóis/metabolismo , Feminino , Humanos , Hiperandrogenismo/etiologia , Hiperandrogenismo/prevenção & controle , Hipertensão/etiologia , Hipertensão/prevenção & controle , Pacientes Desistentes do Tratamento , Projetos Piloto , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/fisiopatologia , Congêneres da Testosterona/sangue , Deficiência de Vitamina D/complicações , Adulto Jovem
20.
Am J Physiol Endocrinol Metab ; 302(3): E297-306, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22045316

RESUMO

Hyperandrogenism and chronic low-grade inflammation are related in polycystic ovary syndrome (PCOS), but it is unknown whether hyperandrogenemia can activate inflammation. We determined the effect of oral androgen administration on fasting and glucose-stimulated nuclear factor-κB (NF-κB) activation and expression and related markers of inflammation in mononuclear cells (MNC) of lean reproductive-age women. Sixteen lean, ovulatory reproductive-age women were treated with 130 mg of DHEA or placebo (n = 8 each) for 5 days in a randomized, controlled, double-blind fashion. Nuclear activation of NF-κB, p65 and p105 NF-κB subunit RNA, TNFα and IL-1ß mRNA, and NF-κB p65 and inhibitory-κB (IκB) protein were quantified from MNC obtained while fasting and 2 h after glucose ingestion, before and after DHEA or placebo administration. Before treatment, subjects receiving DHEA or placebo exhibited no differences in androgens or any inflammatory markers while fasting and after glucose ingestion. Compared with placebo, DHEA administration raised levels of testosterone, androstenedione, and DHEA-S, increased the percent change in fasting and glucose-challenged activated NF-κB, p65, p105, TNFα, and IL-1ß RNA and p65 protein, and decreased the percent change in fasting and glucose-challenged IκB protein. We conclude that elevation of circulating androgens to the range observed in PCOS upregulates the NF-κB inflammation pathway in lean reproductive-age women. Thus, hyperandrogenemia activates and sensitizes MNC to glucose in this population.


Assuntos
Citocinas/metabolismo , Regulação da Expressão Gênica , Hiperandrogenismo/imunologia , Hiperglicemia/etiologia , Leucócitos Mononucleares/imunologia , Adulto , Índice de Massa Corporal , Núcleo Celular/metabolismo , Citocinas/sangue , Citocinas/genética , Desidroepiandrosterona , Método Duplo-Cego , Feminino , Humanos , Hiperandrogenismo/sangue , Hiperandrogenismo/etiologia , Hiperandrogenismo/metabolismo , Proteínas I-kappa B/metabolismo , Leucócitos Mononucleares/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Síndrome do Ovário Policístico/fisiopatologia , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Congêneres da Testosterona/sangue , Adulto Jovem
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