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1.
Drug Test Anal ; 15(11-12): 1361-1370, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37339884

RESUMO

This work focused on the possible alterations of the markers of the steroidal module of the athlete biological passport, considering samples of athletes declaring and not-declaring the supplementation of thyroid hormones (TH) in the Doping Control Form (DCF). Concentrations of 5α-androstane-3α,17ß-diol (5α-Adiol), 5ß-androstane-3α,17ß-diol (5ß-Adiol), testosterone (T), androsterone (A), etiocholanolone (Etio), epitestosterone (E), pregnanediol (PD), dehydroepiandrosterone (DHEA), and 11ß-hydroxy-androsterone (OHA) were calculated using internal standards and external calibration by gas chromatography-tandem mass spectrometry. Also, ratios between the above biomarkers were also estimated. The data set was composed of samples from females and males declaring and not-declaring TH supplementation in the DCF. To corroborate these observations, a controlled urinary excretion study was carried out with multiple doses of sodium liothyronine (T3). Female data showed significant differences for the concentrations of 5α-Adiol, A, DHEA, E, OHA, and T and the ratio A/Etio between FD and FND groups, whereas the male groups only showed significant differences in OHA concentration. In both cases, males and females declaring the consumption of levothyroxine showed narrower data distribution and diminished percentiles from 17% to 67% with respect to the not-declaring corresponding groups (p < 0.05). Concentrations of 5α-metabolites showed a higher depression for the FND, and both FD and MD groups showed a peculiar behavior for the PD concentrations. The controlled study agreed with the observations, mainly for the female group with significant differences for concentrations of E, Etio, 5α-Adiol, and 5ß-Adiol after TH administration. The interpretation of the steroid markers of the ABP should consider TH administrations.


Assuntos
Androsterona , Dopagem Esportivo , Humanos , Masculino , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Testosterona/urina , Esteroides/urina , Atletas , Etiocolanolona , Desidroepiandrosterona/urina
2.
Drug Test Anal ; 15(3): 324-333, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36414566

RESUMO

The steroidal module of the athlete biological passport (ABP) targets the use of pseudo-endogenous androgenous anabolic steroids in elite sport by monitoring urinary steroid profiles. Urine and blood samples were collected weekly during two consecutive oral contraceptive pill (OCP) cycles in 15 physically active women to investigate the low urinary steroid concentrations and putative confounding effect of OCP. In urine, testosterone (T) and epitestosterone (E) were below the limit of quantification of 1 ng/ml in 62% of the samples. Biomarkers' variability ranged between 31% and 41%, with a significantly lesser variability for ratios (except for T/E [41%]): 20% for androsterone/etiocholanolone (p < 0.001) and 25% for 5α-androstane-3α,17ß-diol/5ß-androstane-3α,17ß-diol (p < 0.001). In serum, markers' variability (testosterone: 24%, androstenedione: 23%, dihydrotestosterone: 19%, and T/A4: 16%) was significantly lower than in urine (p < 0.001). Urinary A/Etio increased by >18% after the first 2 weeks (p < 0.05) following withdrawal blood loss. In contrast, serum T (0.98 nmol/l during the first week) and T/A4 (0.34 the first week) decreased significantly by more than 25% and 17% (p < 0.05), respectively, in the following weeks. Our results outline steroidal variations during the OCP cycle, highlighting exogenous hormonal preparations as confounder for steroid concentrations in blood. Low steroid levels in urine samples have a clear negative impact on the subsequent interpretation of steroid profile of the ABP. With a greater analytical sensitivity and lesser variability for steroids in healthy active women, serum represents a complementary matrix to urine in the ABP steroidal module.


Assuntos
Dopagem Esportivo , Humanos , Feminino , Esteroides/urina , Testosterona/urina , Di-Hidrotestosterona/urina , Anticoncepção
3.
Drug Test Anal ; 14(5): 833-850, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-33817997

RESUMO

In women, hormonal fluctuations related to the menstrual cycle may impose a great source of variability for some biomarkers of testosterone (T) administration, which can ultimately disrupt the sensitivity of their longitudinal monitoring. In this study, the sensitivity of the current urinary and haematological markers of the Athlete Biological Passport (ABP), as well as serum steroid biomarkers, was investigated for the monitoring of a 28-day T gel treatment combined with endogenous fluctuation of the menstrual cycle in 14 healthy female subjects. Additionally, the analysis of urinary target compounds was performed on a subset of samples for endogenous/exogenous origin via isotope ratio mass spectrometry (IRMS). In serum, concentrations of T and dihydrotestosterone (DHT) increased significantly during the treatment, whereas in urine matrix the most affected biomarkers were found to be the ratios of testosterone/epitestosterone (T/E) and 5α-androstane-3α,17ß-diol/epitestosterone (5αAdiol/E). The detection capability of both urinary biomarkers was heavily influenced by [E], which fluctuated depending on the menstrual cycle, and resulted in low sensitivity of the urinary steroidal ABP module. On the contrary, an alternative approach by the longitudinal monitoring of serum T and DHT concentrations with the newly proposed T/androstenedione ratio showed higher sensitivity. The confirmatory IRMS results demonstrated that less than one third of the tested urine samples fulfilled the criteria for positivity. Results from this study demonstrated that the 'blood steroid profile' represents a powerful complementary approach to the 'urinary module' and underlines the importance of gathering bundle of evidence to support the scenario of an endogenous prohibited substance administration.


Assuntos
Dopagem Esportivo , Epitestosterona , Biomarcadores/urina , Di-Hidrotestosterona , Feminino , Humanos , Ciclo Menstrual , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Testosterona/urina , Congêneres da Testosterona
4.
Drug Test Anal ; 9(9): 1328-1336, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27717154

RESUMO

Detection of testosterone and/or its pro-drugs in the gelding is currently regulated by the application of an international threshold for urinary testosterone of 20 ng/mL. The use of steroid ratios may provide a useful supplementary approach to aid in differentiating between the administration of these steroids and unusual physiological conditions that may result in atypically high testosterone concentrations. In the current study, an ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was developed to quantify testosterone (T) and epitestosterone (E). The method was used to analyze 200 post-race urine samples from geldings in order to generate the ratios for the reference population. Following statistical analysis of the data, an upper limit of 5 for T:E ratio in geldings is proposed. Samples collected from 15 geldings with atypical urinary testosterone concentrations (>15 ng/mL) but otherwise normal steroid profile, had T:E ratios within those observed for the reference population. The applicability of an upper T:E ratio to detect an administration was demonstrated by the analysis of a selection of incurred samples from testosterone propionate, dehydroepiandrosterone (DHEA), and a mixture of DHEA and pregnenolone (Equi-Bolic®) administrations. These produced testosterone concentrations above the threshold of 20 ng/mL, but also T:E ratios above the proposed limit of 5. In conclusion, consideration of the T:E ratio appears to be a valuable complementary aid to evaluate whether an atypical testosterone concentration could be caused by a natural biological outlier as opposed to the administration of these steroids. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Líquidos Corporais/química , Desidroepiandrosterona/análise , Dopagem Esportivo/estatística & dados numéricos , Epitestosterona/análise , Esteroides/análise , Espectrometria de Massas em Tandem/métodos , Testosterona/análise , Animais , Cromatografia Líquida , Desidroepiandrosterona/urina , Epitestosterona/urina , Cavalos , Humanos , Pró-Fármacos , Esteroides/urina , Detecção do Abuso de Substâncias , Testosterona/urina
5.
Scand J Work Environ Health ; 42(5): 435-46, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27501065

RESUMO

OBJECTIVES: The aims of our study were to (i) investigate the association between rotating night shift work and blood concentrations of estradiol, testosterone and dehydroepiandrosterone sulfate (DHEAS) and (2) evaluate the role of their non-occupational determinants. METHODS: A cross-sectional study was conducted on 345 premenopausal and 187 postmenopausal nurses and midwives (263 women working rotating night shifts and 269 women working during days). Data from in-person interviews were used, anthropometric measurements were performed, and body mass index (BMI) and waist- to-hip ratio were calculated. Morning blood and spot urine samples were collected. Multiple linear regression models were fitted with hormone concentrations as dependent variables, and night shift work characteristics and demographic, reproductive, lifestyle and anthropometric determinants as independent variables. Modification of the effect by chronotype was examined. RESULTS: Among postmenopausal women, we observed a statistically significant positive association between the total duration of night shift work >15 years and estradiol level (P<0.05 when compared to night work duration <5 years). Night shift work characteristics were significantly associated with estradiol among morning-type postmenopausal women. The well-established associations between hormones and their major determinants, such as age and BMI, were confirmed. CONCLUSIONS: The findings of our study imply that prolonged night shift work may be associated with increased estradiol levels among postmenopausal women, especially among the morning-type postmenopausal women.


Assuntos
Sulfato de Desidroepiandrosterona/análise , Estradiol/análise , Tocologia/estatística & dados numéricos , Enfermeiras e Enfermeiros/estatística & dados numéricos , Testosterona/análise , Tolerância ao Trabalho Programado/psicologia , Ritmo Circadiano , Estudos Transversais , Sulfato de Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/urina , Estradiol/sangue , Estradiol/urina , Humanos , Testosterona/sangue , Testosterona/urina
6.
Drug Test Anal ; 8(5-6): 525-34, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27443207

RESUMO

To ensure fair competition and to protect the horse's welfare, horses have to compete on their own merits, without any unfair advantage that might follow the use of drugs. Therefore, regulatory authorities list all substances that are not allowed in competition, including most anabolic-androgenic steroids. As zero-tolerance is retained, the question arose whether the consumption of mouldy feed could lead to the excretion of steroids, due to the biotransformation of plant phytosterols to steroids. A rapid ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analytical method, previously validated according to AORC (Association of Official Racing Chemists) and EC (European Commission) guidelines, was used to measure steroids in different sample types. Multiple mouldy feed samples were tested for the presence of steroids. The effect of digestion was tested by in vitro simulation of the horse's hindgut in batch incubations. In most feed samples no steroids were detected, even when the products were mouldy. Mouldy corn however showed to contain up to 3.0 ± 0.4 µg/kg AED (4-androstenedione), the main testosterone precursor. This concentration increased when mouldy corn (with added phytosterols) was digested in vitro. An herbal phytosupplement also showed to contain α-testosterone. These results demonstrate that it is important to caution against the consumption of any feed or (herbal) supplement of which the detailed ingredients and quantitative analysis are unknown. The consumption of mouldy corn should especially be avoided, not only from a horse health and welfare point of view, but also to avoid possible inadvertent positive doping results. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Anabolizantes/análise , Androgênios/análise , Ração Animal/análise , Ração Animal/microbiologia , Fezes/química , Cavalos/urina , Esteroides/análise , Aerobiose , Anabolizantes/metabolismo , Anabolizantes/urina , Androgênios/metabolismo , Androgênios/urina , Animais , Biotransformação , Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Suplementos Nutricionais/microbiologia , Dopagem Esportivo , Cavalos/metabolismo , Mucor/metabolismo , Mycobacterium/metabolismo , Fitosteróis/análise , Fitosteróis/metabolismo , Fitosteróis/urina , Esteroides/metabolismo , Esteroides/urina , Espectrometria de Massas em Tandem/métodos , Testosterona/análise , Testosterona/metabolismo , Testosterona/urina , Zea mays/química , Zea mays/microbiologia
7.
Steroids ; 114: 68-77, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27016128

RESUMO

Chronic and heavy alcohol consumption disrupts lipid metabolism and hormonal balance including testosterone levels. However, studies doubt the relationship between moderate alcohol intake and sex hormone levels. Therefore, the aim of the present investigation was to establish the direct impact of chronic and moderate alcohol intake on cholesterol homeostasis and steroid hormone synthesis. Asymptomatic chronic and moderate alcoholics (n=12) without chronic liver disease and healthy volunteers (n=14) were selected for the study. Furthermore, effects of standardized water extract of Tinospora cordifolia (Willd) Mier. (Menispermaceae) (TCJ), a well reported anti-alcoholic herbal drug, on urinary steroids was studied. This study included four groups, i.e. a) healthy; b) healthy+TCJ; c) alcoholic; d) alcoholic+TCJ. The blood and urine samples from each group were collected on day 0 and 14 of the post-treatment with TCJ and analyzed. Alcoholic blood samples showed the significantly higher values of traditional biomarkers γ-GT and MCV along with cholesterol, LDL, TGL and urinary methylglucuronide compared to healthy. Qualitative analysis of steroids showed that moderate alcohol intake in a chronic manner increased the cholesterol synthesis and directed its flow toward C-21 steroids; shown by increased levels of corticosterone (2.456 fold) and cortisol (3.7 fold). Moreover, alcohol intake also increased the synthesis of estradiol and clearance rate of other steroids through the formation of glucuronides. Therefore, it decreased the synthesis and increased the clearance rate of testosterone (T) and androstenedione (A). Quantitative analysis confirmed decreased T/A ratio from 2.31 to 1.59 in plasma and 2.47 to 1.51 in urine samples of alcoholics. TCJ intervention normalized the levels of steroids and significantly improved the T:A ratio to 2.0 and 2.12 in plasma and urine. The study revealed that TCJ modulated lipid metabolism by inhibiting cholesterol and glucuronides synthesis.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Esteroides/sangue , Esteroides/urina , Tinospora/química , Adulto , Alcoolismo/sangue , Alcoolismo/tratamento farmacológico , Alcoolismo/urina , Androstenodiona/sangue , Androstenodiona/urina , Cromatografia Líquida , Estradiol/sangue , Estradiol/urina , Voluntários Saudáveis , Humanos , Masculino , Espectrometria de Massas , Extratos Vegetais/uso terapêutico , Testosterona/sangue , Testosterona/urina
8.
PLoS One ; 10(10): e0140728, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26491965

RESUMO

Cigarette use is an independent risk factor for the development of erectile dysfunction (ED). While the association between chronic smoking and ED is well established, the fundamental mechanism(s) of cigarette-related ED are incompletely understood, partly due to no reliable animal model of smoking-induced ED. The present study was designed to validate an in vivo rat model of chronic cigarette-induced ED. Forty 12-week old male Sprague-Dawley rats were divided into 4 groups. Ten rats served as control group and were exposed only to room air. The remaining 30 rats were passively exposed to cigarette smoke (CS) for 4 weeks (n = 10), 12 weeks (n = 10), and 24 weeks (n = 10). At the 24-week time point all rats were assessed with intracavernous pressure (ICP) during cavernous nerve electrostimulation. Blood and urine were collected to measure serum testosterone and oxidative stress, respectively. Corporal tissue was assessed by Western blot for neuronal nitric oxide synthase (nNOS). Penile tissues were subjected to immunohistochemistry for endothelial, smooth muscle, and apoptotic content. Mean arterial pressure (MAP) was significantly higher in 24-week cigarette exposed animals compared to the control animals. Mean ICP/MAP ratio and cavernosal smooth muscle/endothelial contents were significantly lower in the 12- and 24-week rats compared to control animals. Oxidative stress was significantly higher in the 24-week cigarette exposed group compared to control animals. Mean nNOS expression was significantly lower, and apoptotic index significantly higher, in CS-exposed animals compared to control animals. These findings indicate that the rat model exposure to CS increases apoptosis and oxidative stress and decreases nNOS, endothelial and smooth muscle contents, and ICP in a dose dependent fashion. The rat model is a useful tool for further study of the molecular and cellular mechanisms of CS-related ED.


Assuntos
Apoptose , Endotélio/patologia , Músculo Liso/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Estresse Oxidativo , Ereção Peniana , Fumar , Animais , Western Blotting , Peso Corporal , Modelos Animais de Doenças , Estimulação Elétrica , Endotélio/enzimologia , Endotélio/fisiopatologia , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Ratos Sprague-Dawley , Testosterona/sangue , Testosterona/urina
9.
J Steroid Biochem Mol Biol ; 152: 180-92, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26094581

RESUMO

Traditionally, steroids other than testosterone are considered to be synthetic, anabolic steroids. Nevertheless, in stallions, it has been shown that ß-Bol can originate from naturally present testosterone. Other precursors, including phytosterols from feed, have been put forward to explain the prevalence of low levels of steroids (including ß-Bol and ADD) in urine of mares and geldings. However, the possible biotransformation and identification of the precursors has thus far not been investigated in horses. To study the possible endogenous digestive transformation, in vitro simulations of the horse hindgut were set up, using fecal inocula obtained from eight different horses. The functionality of the in vitro model was confirmed by monitoring the formation of short-chain fatty acids and the consumption of amino acids and carbohydrates throughout the digestion process. In vitro digestion samples were analyzed with a validated UHPLC-MS/MS method. The addition of ß-Bol gave rise to the formation of ADD (androsta-1,4-diene-3,17-dione) or αT. Upon addition of ADD to the in vitro digestions, the transformation of ADD to ß-Bol was observed and this for all eight horses' inocula, in line with previously obtained in vivo results, again confirming the functionality of the in vitro model. The transformation ratio proved to be inoculum and thus horse dependent. The addition of pure phytosterols (50% ß-sitosterol) or phytosterol-rich herbal supplements on the other hand, did not induce the detection of ß-Bol, only low concentrations of AED, a testosterone precursor, could be found (0.1 ng/mL). As such, the digestive transformation of ADD could be linked to the detection of ß-Bol, and the consumption of phytosterols to low concentrations of AED, but there is no direct link between phytosterols and ß-Bol.


Assuntos
Androstadienos/urina , Androstenodiona/urina , Digestão/fisiologia , Fitosteróis/metabolismo , Testosterona/análogos & derivados , Aminoácidos/metabolismo , Anabolizantes/metabolismo , Androgênios/metabolismo , Androstadienos/metabolismo , Androstenodiona/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Carboidratos da Dieta/metabolismo , Ácidos Graxos Voláteis/biossíntese , Feminino , Cavalos , Masculino , Mycobacterium/metabolismo , Esteroides/metabolismo , Espectrometria de Massas em Tandem , Testosterona/metabolismo , Testosterona/urina
10.
Drug Test Anal ; 7(1): 39-47, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25242721

RESUMO

In order to ensure the welfare of performance horses and riders as well as the integrity of the sport, the use of both therapeutic and illegal agents in horse racing is tightly regulated. While Dehydroepiandrosterone (DHEA) is not specifically banned from administration to racehorses in the United States and no screening limit or threshold concentration exists, the metabolic conversion of DHEA to testosterone make its presence in nutritional supplements a regulatory concern. The recommended regulatory threshold for total testosterone in urine is 55 and 20 ng/mL for mares and geldings, respectively. In plasma, screening and confirmation limits for free testosterone (mares and geldings), of no greater than 0.1 and 0.025 ng/mL, respectively are recommended. DHEA was administered orally, as part of a nutritional supplement, to 8 exercised female thoroughbred horses and plasma and urine samples collected at pre-determined times post administration. Using liquid chromatography-mass spectrometry (LC-MS), plasma and urine samples were analyzed for DHEA, DHEA-sulfate, testosterone, testosterone-sulfate, pregnenolone, androstenedione, and androstenediol. DHEA was rapidly absorbed with maximal plasma concentrations reaching 52.0 ± 43.8 ng/mL and 32.1 ± 12.9 ng/mL for DHEA and DHEA sulfate, respectively. Free testosterone was not detected in plasma or urine samples at any time. Maximum sulfate conjugated testosterone plasma concentrations were 0.98 ± 1.09 ng/mL. Plasma testosterone-sulfate concentrations did not fall below 0.1 ng/mL and urine testosterone-sulfate below 55 ng/mL until 24-36 h post DHEA administration. Urine testosterone sulfate concentrations remained slightly above baseline levels at 48 h for most of the horses studied.


Assuntos
Desidroepiandrosterona/sangue , Desidroepiandrosterona/urina , Cavalos/sangue , Cavalos/urina , Animais , Cromatografia Líquida , Desidroepiandrosterona/administração & dosagem , Desidroepiandrosterona/metabolismo , Suplementos Nutricionais/análise , Dopagem Esportivo , Feminino , Cavalos/metabolismo , Espectrometria de Massas , Metaboloma , Metabolômica , Testosterona/sangue , Testosterona/metabolismo , Testosterona/urina
11.
Artigo em Inglês | MEDLINE | ID: mdl-25156963

RESUMO

This study proposes a new analytical methodology for the determination of trace levels of testosterone (T) and epitestosterone (E) in urine matrices using bar adsorptive microextraction combined with liquid desorption followed by high-performance liquid chromatography with diode array detection (BAµE-LD/HPLC-DAD). The comparison of different sorbent coatings (five activated carbons, one styrene-divinylbenzene, two modified pyrrolidone, one ciano and one n-vinylpyrrolidone polymers) through BAµE showed that the latter phase presented much higher selectivity and capacity offering multiple mechanisms of interaction. Assays using this phase were performed on 25mL of water samples spiked at the 8.0µg/L level, yielded average recoveries of 92.1 and 93.4% for T and E, respectively, under optimized experimental conditions; BAµE (n-vinylpyrrolidone): 16h (1000rpm), pH 5.5; LD: acetonitrile, 30min under sonication treatment. From the developed analytical methodology, suitable detection limits were achieved (0.4µg/L) and good linear dynamic ranges (1.4-16.0µg/L) with remarkable determination coefficients (r(2)>0.9978). By using the standard addition methodology, the application of the present analytical approach on urine samples revealed good sensitivity. The proposed method, which operated under the floating sampling technology, proved to be a suitable sorption-based static microextraction alternative for screening T, E and the T/E ratio in urine samples for doping control purposes. The methodology showed to be easy to implement, demonstrating good reproducibility, sensitivity and robustness, allowing the possibility to choose the most selective sorbent coating according to the compounds of interest.


Assuntos
Fracionamento Químico/métodos , Dopagem Esportivo , Avaliação Pré-Clínica de Medicamentos/métodos , Epitestosterona/urina , Testosterona/urina , Adulto , Cromatografia Líquida de Alta Pressão , Epitestosterona/química , Epitestosterona/isolamento & purificação , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Reprodutibilidade dos Testes , Testosterona/química , Testosterona/isolamento & purificação
12.
Reproduction ; 143(1): 123-32, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22016382

RESUMO

Androgen-dependent urinary constituents from males hasten reproductive maturation (the Vandenbergh effect) and disrupt peri-implantation pregnancy (the Bruce effect) in nearby females. Each of these effects can be mimicked in socially isolated females by direct administration of exogenous oestrogens. The current experiments were designed to determine the role of males' urinary 17ß-oestradiol (E(2)) in their capacities to induce these effects. A preliminary experiment showed that both males on a phyto-oestrogen-rich soy-based diet and those on a phyto-oestrogen-free diet could induce both effects. For subsequent experiments, males were castrated and treated with either oil vehicle or E(2). Enzyme immunoassay was conducted on non-invasively collected urine samples from these males. Concentrations of urinary testosterone were subnormal in both conditions, but urinary E(2) was restored to the normal range for intact males in castrates given E(2). Urinary creatinine was also quantified as a measure of hydration and was significantly reduced in males treated with E(2). Castration diminished the capacity of males to promote growth of the immature uterus and also their capacity to disrupt blastocyst implantation in inseminated females. Injections of E(2) to castrated males restored both capacities. These data converge with other studies indicating that E(2) is the main constituent of male urine responsible for induction of both the Vandenbergh and the Bruce effects.


Assuntos
Estradiol/farmacologia , Reprodução/efeitos dos fármacos , Reprodução/fisiologia , Animais , Creatinina/urina , Dieta , Implantação do Embrião/efeitos dos fármacos , Implantação do Embrião/fisiologia , Estradiol/urina , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Orquiectomia , Fitoestrógenos/administração & dosagem , Gravidez , Comportamento Sexual Animal/efeitos dos fármacos , Comportamento Sexual Animal/fisiologia , Testosterona/urina
13.
Steroids ; 76(6): 540-7, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21310167

RESUMO

New analogues of androgens that had never been available as approved drugs are marketed as "dietary supplement" recently. They are mainly advertised to promote muscle mass and are considered by the governmental authorities in various countries, as well as by the World Anti-doping Agency for sport, as being pharmacologically and/or chemically related to anabolic steroids. In the present study, we report the detection of a steroid in a product seized by the State Bureau of Criminal Investigation Schleswig-Holstein, Germany. The product "1-Androsterone" of the brand name "Advanced Muscle Science" was labeled to contain 100mg of "1-Androstene-3b-ol,17-one" per capsule. The product was analyzed underivatized and as bis-TMS derivative by GC-MS. The steroid was identified by comparison with chemically synthesized 3ß-hydroxy-5α-androst-1-en-17-one, prepared by reduction of 5α-androst-1-ene-3,17-dione with LS-Selectride (Lithium tris-isoamylborohydride), and by nuclear magnetic resonance. Semi-quantitation revealed an amount of 3ß-hydroxy-5α-androst-1-en-17-one in the capsules as labeled. Following oral administration to a male volunteer, the main urinary metabolites were monitored. 1-Testosterone (17ß-hydroxy-5α-androst-1-en-3-one), 1-androstenedione (5α-androst-1-ene-3,17-dione), 3α-hydroxy-5α-androst-1-en-17-one, 5α-androst-1-ene-3α,17ß-diol, and 5α-androst-1-ene-3ß,17ß-diol were detected besides the parent compound and two more metabolites (up to now not finally identified but most likely C-18 and C-19 hydroxylated 5α-androst-1-ene-3,17-diones). Additionally, common steroids of the urinary steroid profile were altered after the administration of "1-Androsterone". Especially the ratios of androsterone/etiocholanolone and 5α-/5ß-androstane-3α,17ß-diol and the concentration of 5α-dihydrotestosterone were influenced. 3α-Hydroxy-5α-androst-1-en-17-one appears to be suitable for the long-term detection of the steroid (ab-)use, as this characteristic metabolite was detectable in screening up to nine days after a single administration of one capsule.


Assuntos
Anabolizantes/análise , Androsterona/análogos & derivados , Suplementos Nutricionais/análise , Detecção do Abuso de Substâncias/métodos , Testosterona/análogos & derivados , Idoso , Anabolizantes/farmacocinética , Androstano-3,17-diol/urina , Androsterona/química , Androsterona/farmacocinética , Androsterona/urina , Di-Hidrotestosterona/urina , Etiocolanolona/urina , Humanos , Masculino , Testosterona/química , Testosterona/urina
14.
Eur J Clin Nutr ; 63(1): 65-70, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17882141

RESUMO

OBJECTIVES: To investigate whether the administration of the zinc-containing nutritional supplement ZMA causes an increase of serum testosterone levels, which is an often claimed effect in advertising for such products; to monitor the urinary excretion of testosterone and selected steroid hormone metabolites to detect potential changes in the excretion patterns of ZMA users. SUBJECTS: Fourteen healthy, regularly exercising men aged 22-33 years with a baseline zinc intake between 11.9 and 23.2 mg day(-1) prior to the study. RESULTS: Supplementation of ZMA significantly increased serum zinc (P=0.031) and urinary zinc excretion (P=0.035). Urinary pH (P=0.011) and urine flow (P=0.045) were also elevated in the subjects using ZMA. No significant changes in serum total and serum free testosterone were observed in response to ZMA use. Also, the urinary excretion pattern of testosterone metabolites was not significantly altered in ZMA users. CONCLUSIONS: The present data suggest that the use of ZMA has no significant effects regarding serum testosterone levels and the metabolism of testosterone in subjects who consume a zinc-sufficient diet.


Assuntos
Androgênios/metabolismo , Suplementos Nutricionais , Testosterona/metabolismo , Zinco/farmacologia , Adulto , Androgênios/sangue , Combinação de Medicamentos , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Magnésio/farmacologia , Masculino , Testosterona/sangue , Testosterona/urina , Micção/efeitos dos fármacos , Urina/química , Vitamina B 6/farmacologia , Adulto Jovem , Zinco/sangue , Zinco/urina
15.
Steroids ; 73(11): 1143-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18550137

RESUMO

The classical analytical method for detection of anabolic steroid abuse is gas chromatography followed by mass spectrometry (GC/MS). However, even molecules with a chemical structure typical for this class of substances, are sometimes not identified in routine screening by GC/MS when their precise chemical structure is still unknown. A supplementary approach to identify anabolic steroid abuse could be a structure-independent identification of anabolic steroids based on their biological activity. To test the suitability of such a system, we have analyzed the yeast androgen receptor (AR) reporter gene system to identify anabolic steroids in human urine samples. Analysis of different anabolic steroids dissolved in buffer demonstrated that the yeast reporter gene system is able to detect a variety of different anabolic steroids and their metabolites with high specificity, including the so-called 'designer steroid' tetrahydrogestrinone. In contrast, other non-androgenic steroids, like glucocordicoids, progestins, mineralocordicoids and estrogens had a low potency to stimulate transactivation. To test whether the system would also allow the detection of androgens in urine, experiments with spiked urine samples were performed. The androgen reporter gene in yeast responds very sensitive to 5alpha-dihydrotestosterone (DHT), even at high urine concentrations. To examine whether the test system would also be able to detect anabolic steroids in the urine of anabolic steroid abusers, anonymous urine samples previously characterized by GCMS were analyzed with the reporter gene assay. Even when the concentration of the anabolic metabolites was comparatively low in some positive samples it was possible to identify the majority of positive samples by their biological activity. In conclusion, our results demonstrate that the yeast reporter gene system detects anabolic steroids and corresponding metabolites with high sensitivity even in urine of anabolic steroid abusing athletes. Therefore we believe that this system can be developed towards a powerful (pre) screening tool for the established doping tests. The system is easy to handle, robust, cost-efficient and needs no high-tech equipment. But most importantly, a biological test system does not require knowledge of the chemical structure of androgenic substances and therefore suitable to detect previously unidentified substances, especially those of the class of so-called designer steroids.


Assuntos
Anabolizantes/urina , Androgênios/urina , Saccharomyces cerevisiae/metabolismo , Detecção do Abuso de Substâncias/métodos , Ativação Transcricional , Anabolizantes/metabolismo , Bioensaio , Drogas Desenhadas/análise , Di-Hidrotestosterona/metabolismo , Di-Hidrotestosterona/urina , Relação Dose-Resposta a Droga , Genes Reporter , Gestrinone/análogos & derivados , Gestrinone/metabolismo , Gestrinone/urina , Humanos , Masculino , Norpregnenos/metabolismo , Norpregnenos/urina , Receptores Androgênicos/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Saccharomyces cerevisiae/genética , Sensibilidade e Especificidade , Testosterona/análogos & derivados , Testosterona/metabolismo , Testosterona/urina , beta-Galactosidase/metabolismo
16.
Int J Sports Med ; 25(2): 124-9, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14986195

RESUMO

Several recent studies have shown evidence of some nutritional supplements containing prohibited anabolic androgenic steroids, so-called prohormones, which were not declared on the label. Therefore, a broad-based investigation of the international nutritional supplement market was initiated to clarify the extent of this problem. From October 2000 until November 2001, 634 non-hormonal nutritional supplements were purchased in 13 countries from 215 different suppliers. Most supplements were bought in shops in the respective countries (578 samples = 91.2 %) and on the internet (52 samples = 8.2 %). 289 supplements were from prohormone-selling companies and 345 supplements came from companies which do not offer prohormones. After isolation from the supplement matrix 11 different anabolic androgenic steroids, mainly prohormones of testosterone and nandrolone, were analysed by gas-chromatography/mass spectrometry. Out of the 634 samples analysed 94 (14.8 %) contained anabolic androgenic steroids not declared on the label ("positive supplements"). We could not obtain reliable data for 66 samples (10.4 %) due to matrix effects. In relation to the total number of products purchased per country, most of the positive supplements were bought in the Netherlands (25.8 %), in Austria (22.7 %), in the UK (18.8 %) and the USA (18.8 %). According to the label, all positive supplements were from companies located in only five countries: the USA, the Netherlands, the UK, Italy and Germany. 21.1 % of the nutritional supplements from prohormone-selling companies contained anabolic androgenic steroids, whereas 9.6 % of the supplements from companies not selling prohormones were positive. The positive supplements showed anabolic androgenic steroid concentrations of 0.01 micro g/g up to 190 micro g/g. The administration of supplements containing nandrolone prohormones adding up to a total uptake of more than 1 micro g resulted in positive doping results for norandrosterone for several hours.


Assuntos
Anabolizantes , Suplementos Nutricionais , Adulto , Anabolizantes/análise , Suplementos Nutricionais/análise , Dopagem Esportivo/prevenção & controle , Epitestosterona/urina , Glucuronídeos/urina , Humanos , Internacionalidade , Masculino , Pessoa de Meia-Idade , Vigilância de Produtos Comercializados/métodos , Testosterona/urina
17.
Cancer Epidemiol Biomarkers Prev ; 12(6): 497-502, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12814993

RESUMO

Steroid sex hormones play a central role in breast carcinogenesis. Evidence from in vitro and animal studies suggests that phytoestrogens may inhibit the development of mammary tumors through their role in regulating the synthesis, metabolism, and signal transduction of steroid hormones. In a study of 117 case-control pairs of postmenopausal women in Shanghai, we investigated whether the association between urinary phytoestrogen excretion and breast cancer risk may differ by levels of endogenous steroid sex hormones, sex hormone binding globulin (SHBG), body mass index (BMI), and waist:hip ratio (WHR). Fasting morning blood and urine samples were collected for the analysis of urinary isoflavonoids and mammalian lignans, as well as blood levels of SHBG and selected steroid hormones. For cancer patients, samples were collected before any cancer therapy. Conditional logistic regression models were used to estimate odds ratios and 95% confidence intervals after adjusting for potential confounding factors. The inverse associations between urinary phytoestrogens and breast cancer risk were found to be more evident among women with a high BMI or WHR than those with a low level of these anthropometric measurements. Although a reduced risk of breast cancer was observed among women with a high excretion rate of urinary isoflavonoids in all of the strata defined by blood SHBG and steroid hormones, the inverse association was more pronounced among women with a high blood concentration of estradiol, a low level of estrone sulfate, or a low level of SHBG. The risks of breast cancer were also reduced with increasing excretion rate of mammalian lignans, although no test for a linear association was statistically significant in stratified analyses. Findings from this study suggest that the potential protective association of phytoestrogens may be modified by BMI, WHR, and blood levels of SHBG, and steroid hormones.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/metabolismo , Fibroadenoma/epidemiologia , Fibroadenoma/metabolismo , Isoflavonas/urina , Preparações de Plantas/urina , Adulto , Fatores Etários , Antropometria , Biomarcadores Tumorais/urina , Índice de Massa Corporal , Peso Corporal , Estudos de Casos e Controles , China/epidemiologia , Sulfato de Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona/urina , Ingestão de Alimentos , Estrogênios/sangue , Estrogênios/urina , Feminino , Humanos , Isoflavonas/sangue , Menopausa/metabolismo , Pessoa de Meia-Idade , Fitoestrógenos , Fatores de Risco , Globulina de Ligação a Hormônio Sexual/metabolismo , Estatística como Assunto , Testosterona/sangue , Testosterona/urina , Saúde da Mulher
18.
J Med Food ; 6(4): 387-90, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14977449

RESUMO

The equilibrium of sexual hormones in both sexes is controlled in vertebrates by the enzyme aromatase, a member of the cytochrome P450 superfamily, which catalyzes the conversion of androstenedione and testosterone into estrone and estradiol, respectively. Flavonoids are diphenolic compounds present in whole grains, legumes, fruits, and vegetables that are strongly implicated as protective in coronary heart disease, stroke, and cancer. One flavonoid, chrysin, found in high concentrations in honey and propolis, has been shown to be an inhibitor of aromatase enzyme activity. These foods are often used as supplements, particulary by sportsmen for their energetic and antioxidant properties. The aim of this study was to verify if daily treatment for 21 days with propolis and honey, containing chrysin, would modify urinary concentrations of testosterone in volunteer male subjects. In fact, aromatase inhibition by chrysin could block the conversion of androgens into estrogens with a consequent increase of testosterone, eventually measurable in urine samples. The obtained data did not show alterations of the levels of testosterone in the volunteers after 7, 14, and 21 days of treatment in comparison with baseline values and compared with measurements on the control subjects at the same time. In conclusion, the use of these foods for 21 days at the doses usually taken as oral supplementation does not have effects on the equilibrium of testosterone in human males.


Assuntos
Inibidores da Aromatase , Flavonoides/farmacologia , Testosterona/urina , Administração Oral , Adulto , Antagonistas de Androgênios/farmacologia , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais , Cromatografia Gasosa-Espectrometria de Massas , Mel , Humanos , Masculino , Própole/química
19.
Life Sci ; 70(23): 2769-82, 2002 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-12269381

RESUMO

To investigate the pituitary-testicular function in nephrotic rats, a sequence of experiments was undertaken in adult male rats after a single dose of puromycin aminonucleoside (PAN). Endocrine modifications were evaluated chronologically throughout the experimental disease in order to determine the appearance of hormone alterations which lead to the axis dysfunction. Serum concentration of LH, FSH, androstenedione, total and free testosterone, estradiol as well as urine testosterone were measured by specific RIAs on days 3, 7 and 10 after treatment on nephrotic and control groups. Prolactin was also evaluated on day 10. Likewise, total weight of various androgen responsive tissues from both groups was recorded, and the number of androgen receptor (AR) binding sites were determined. To know the functional status of the hipophyseal-testicular unit, groups of nephrotic and control rats were stimulated with LHRH (300 ng/100 g b.w.) or with one or four doses of hCG (8 UI), respectively. Additionally, the relative in vitro biological activity of FSH from nephrotic and control rats before and after LHRH stimulus was determined. The results from the hormonal profile revealed clear endocrine disorders characterized by a progressive diminution of all serum hormones except prolactin and urine testosterone, which remained unmodified. The weight of the main androgen responsive tissues, the ventral prostate and the seminal vesicle, decreased parallelly to androgen diminution. The binding analysis of AR shows a significant elevation of the available androgen sites in all analyzed tissues except kidney and hypothalamus. The secretion of LH and FSH from nephrotic animals after LHRH administration was lower than that from intact animals at the registered times. Interestingly, the biological activity of FSH from nephrotic rats was not detectable at both, before and after LHRH administration. Testicular response to hCG stimuli, in terms of testosterone synthesis was not significantly different in the two groups analyzed with respect to the intact animals. By contrast, no response was observed in terms of estradiol production at either one or four doses of hCG. On the whole, the results presented herein allow us to conclude that experimental nephrosis has a harmful effect on the pituitary-testicular axis, and strongly suggests that the endocrine dysfunction is initiated at the hypophyseal level; even though a specific testicular damage is also present.


Assuntos
Nefrose/fisiopatologia , Hipófise/fisiopatologia , Testículo/fisiopatologia , Androstenodiona/sangue , Animais , Gonadotropina Coriônica/administração & dosagem , Gonadotropina Coriônica/farmacologia , AMP Cíclico/imunologia , AMP Cíclico/metabolismo , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/farmacologia , Hipotálamo/fisiologia , Hormônio Luteinizante/sangue , Masculino , Nefrose/sangue , Nefrose/induzido quimicamente , Prolactina/sangue , Puromicina Aminonucleosídeo/toxicidade , Radioimunoensaio , Ratos , Ratos Wistar , Receptores Androgênicos/metabolismo , Testosterona/sangue , Testosterona/urina
20.
J Sci Med Sport ; 3(1): 79-83, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10839231

RESUMO

Six healthy, recreationally active, males undertook two weeks supplementation with beta-Hydroxy beta-Methylbutyrate (HMB). Supplementation was in capsule form with 3 g consumed each day in three even doses of 1 g at main meals. Mid stream urine samples were collected prior to, as well as, after one and two weeks of supplementation and subsequently analysed for testosterone and epitestosterone. The testosterone: epitestosterone ratio was not affected by 2 weeks of HMB supplementation (mean +/- SD baseline 1.02 +/- 0.68; week one 0.98 +/- 0.61; week two 0.92 +/- 0.62). Our results support the claim that supplementation with HMB at the doses recommended will not influence the urinary testosterone: epitestosterone ratio and thus not breach doping policies of the International Olympic Committee for exogenous testosterone or precursor administration.


Assuntos
Dopagem Esportivo , Epitestosterona/urina , Testosterona/urina , Valeratos/administração & dosagem , Adulto , Suplementos Nutricionais , Humanos , Agências Internacionais , Masculino
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