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1.
Rapid Commun Mass Spectrom ; 36(17): e9343, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35737649

RESUMO

RATIONALE: The anabolic steroid 5α-androst-2-en-17-one (2EN) is sold as a prohormone and has been investigated regarding its potential as a steroidal aromatase inhibitor. The administration of 2EN was detected in a doping control sample in 2015, and investigations into its metabolism allowed for the identification and characterization of three urinary metabolites. Unfortunately, the utility of the main metabolite 2ß,3α-dihydroxy-5α-androstan-17-one for doping control purposes was hampered under routine doping control conditions due to chromatographic issues, thus warranting further studies on the metabolism of the prohibited substance. METHODS: The metabolism of 2EN was reinvestigated after oral administration of twofold-deuterated 2EN employing hydrogen isotope ratio mass spectrometry (IRMS) in combination with high-accuracy/high-resolution mass spectrometry. After a single dose of 50 mg of doubly labeled 2EN, urine samples were collected for 9 days. All samples were processed using routine doping control methods for IRMS analysis, and all detected metabolites were further characterized by mass spectrometry-based investigations. RESULTS: More than 15 different metabolites still containing the deuterium label were detected after administration. The presence of steroids exhibiting a 5ß-configuration was unexpected as the administered 2EN features a 5α-configured pharmacophore. Further investigations corroborated a significant impact of the administered 2EN on etiocholanolone and 5ß-androstanediol. Seven metabolites of 2EN not present as endogenous compounds were identified as potential candidates for routine doping controls and could be detected for up to 9 days after administration. CONCLUSIONS: The new metabolites identified in this study enable the detection of the misuse of 2EN for up to 9 days. The conversion of a 5α-steroid to urinary metabolites with 5ß-configuration has not been reported so far and should be further investigated.


Assuntos
Dopagem Esportivo , Etiocolanolona , Androstenos , Etiocolanolona/urina , Espectrometria de Massas/métodos , Esteroides/urina , Detecção do Abuso de Substâncias/métodos
2.
Drug Test Anal ; 13(11-12): 1835-1851, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34648228

RESUMO

The testing strategy for the detection of testosterone (T) or T-prohormones is based on the longitudinal evaluation of urinary steroid concentrations accompanied by subsequent isotope ratio mass spectrometry (IRMS)-based confirmation of samples showing atypical concentrations or concentration ratios. In recent years, the IRMS methodology focussed more and more on T itself and on the metabolites of T, 5α- and 5ß-androstanediol. These target analytes showed the best sensitivity and retrospectivity, but their use has occasionally been challenging due to their comparably low urinary concentrations. Conversely, the carbon isotope ratios (CIR) of the main urinary metabolites of T, androsterone (A) and etiocholanolone (EITO), can readily be measured even from low urine volumes; those however, commonly offer a lower sensitivity and shorter retrospectivity in uncovering T misuse. Within this study, the CIRs of A and ETIO were combined with their urinary concentrations, resulting in a single parameter referred to as 'difference from weighted mean' (DWM). Both glucuronidated and sulfated steroids were investigated, encompassing a reference population (n = 110), longitudinal studies on three individuals, influence of ethanol in two individuals, and re-analysis of several administration studies including T, dihydrotestosterone, androstenedione, epiandrosterone, dehydroepiandrosterone, and T-gel. Especially DWM calculated for the sulfoconjugated steroids significantly prolonged the detection time of steroid hormone administrations when individual reference ranges were applied. Administration studies employing T encompassing CIR common for Europe (-23.8‰ and -24.4‰) were investigated and, even though for a significantly shorter time period and less pronounced, DWM could demonstrate the exogenous source of T metabolites.


Assuntos
Androsterona/análise , Etiocolanolona/análise , Congêneres da Testosterona/análise , Testosterona/análise , Androsterona/urina , Isótopos de Carbono , Dopagem Esportivo/prevenção & controle , Etanol/administração & dosagem , Etanol/farmacologia , Etiocolanolona/urina , Feminino , Humanos , Estudos Longitudinais , Masculino , Espectrometria de Massas/métodos , Pessoa de Meia-Idade , Detecção do Abuso de Substâncias/métodos , Testosterona/urina , Congêneres da Testosterona/urina
3.
Minerva Urol Nephrol ; 73(1): 98-106, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-31833333

RESUMO

BACKGROUND: The serum prostate-specific antigen is the most widespread biomarker for prostate disease. Its low specificity for prostatic malignancies is a matter of concern and the reason why new biomarkers for screening purposes are needed. The correlation between altered production of the main steroids and prostate carcinoma (PCa) occurrence is historically known. The purpose of this study is to evaluate the modifications of a comprehensive urinary endogenous steroidal profile (USP) induced by PCa, by multivariate statistical methods. METHODS: A total of 283 Italian subjects were included in the study, 139 controls and 144 PCa-affected patients. The USP, including 17 steroids and five urinary steroidal ratios, was quantitatively evaluated using gas chromatography coupled with single quadrupole mass spectrometry (GC-MS). The data were interpreted using a chemometric, multivariate approach (intrinsically more sensible to alterations with respect to traditional statistics) and a model for the discrimination of cancer-affected profiles was built. RESULTS: Two multivariate classification models were calculated, the former including three steroids with the highest statistical significance (e.g. testosterone, etiocholanolone and 7ß-OH-DHEA) and PSA values, the latter considering the three steroids' levels only. Both models yielded high sensitivity and specificity scores near to 70%, resulting significantly higher than PSA alone. CONCLUSIONS: Three USP steroids resulted significantly altered in our PCa population. These preliminary results, combined with the simplicity and low-cost of the analysis, open to further investigation of the potential role of this restricted USP in PCa diagnosis.


Assuntos
Desidroepiandrosterona/análogos & derivados , Neoplasias da Próstata/urina , Esteroides/urina , Idoso , Biomarcadores/urina , Desidroepiandrosterona/urina , Etiocolanolona/urina , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Análise Multivariada , Estudos Prospectivos , Antígeno Prostático Específico/urina , Sensibilidade e Especificidade , Testosterona/urina
4.
J Pharmacol Toxicol Methods ; 106: 106938, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33080389

RESUMO

BACKGROUND: Urinary sulfate fraction of the anabolic androgenic steroids is not analyzed routinely in anti-doping analyses but has demonstrated in the last years an increasing interest among the anti-doping community. Sulfate conjugates are linked to plasma proteins increasing the residence time in the body compared to glucuro-conjugated metabolites, and then their analyses may allow improving the detection time window of specific metabolites. Hydrolysis of sulfates can be made enzymatically or chemically and can be challenging, depending on the strategy selected. METHODS: Hydrolysis by solvolysis was validated for metabolic studies, focusing on setting a quality control able to assess the hydrolytic step. To the internal standards mixture, androsterone-D4 and etiocholanolone-D5 sulfate were added. The proposed protocol was applied over samples collected after dehydroepiandrosterone (DHEA) administrations. RESULTS: The stability of the structures showed good results, and no evident formation of degradation products was observed. Internal standard to monitor the efficiency of hydrolysis, recovery, and retention time was successfully introduced. Additional analytes (4ß-hydroxy-DHEA, 5-androstene-3ß,17ß-diol and 5α-androstane-3ß,17ß-diol) were found to be affected besides of DHEA and epiandrosterone (epiA) as previously described. CONCLUSIONS: Results in terms of linearity, precision, and accuracy, showed that the method is suitable to quantify seven analytes in urine in the sulfated fraction. The validated method was successfully applied to urine samples after administration of DHEA to detect this compound in the sulfate fraction and preliminarily to negative samples from athletes of both sexes, to determine Q1 and Q3 inter-quartiles. A quality control assessment for the hydrolysis efficiency was established for every individual sample.


Assuntos
Sulfato de Desidroepiandrosterona/análise , Dopagem Esportivo/prevenção & controle , Detecção do Abuso de Substâncias/métodos , Administração Oral , Adulto , Androsterona/análogos & derivados , Androsterona/análise , Androsterona/química , Androsterona/urina , Sulfato de Desidroepiandrosterona/administração & dosagem , Sulfato de Desidroepiandrosterona/química , Sulfato de Desidroepiandrosterona/urina , Etiocolanolona/análise , Etiocolanolona/química , Etiocolanolona/urina , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Voluntários Saudáveis , Humanos , Hidrólise , Masculino , Pessoa de Meia-Idade , Padrões de Referência
5.
Rapid Commun Mass Spectrom ; 33(6): 579-586, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30589473

RESUMO

RATIONALE: Isotope ratio mass spectrometry (IRMS) is an analytical technique required by the World Antidoping Agency (WADA) before releasing of an adverse finding for the abuse of pseudoendogenous steroids (i.e. testosterone). For every single individual, the delta 13 C values (‰) of the selected target compounds (TCs, i.e. testosterone and/or its precursors/metabolites) are compared with those of endogenous reference compounds (ERCs). The aim of this work is to investigate the individual variation in the delta values of four different commonly used ERCs to establish the maximum acceptable variation, in order to detect potential outliers. METHODS: Routine urine samples collected for antidoping purposes were submitted to IRMS confirmation. After a specific liquid chromatographic purification of the analytes of interest, the final extracts were analyzed by gas chromatography/combustion (GC/C)-IRMS. The selected ERCs monitored were pregnanediol, pregnanetriol, 11-keto-etiocholanolone and 11ß-hydroxyandrosterone. The obtained 13 C delta values were statistically analyzed to evaluate their inter- and intra-individual distribution. RESULTS: The delta values of the ERCs studied showed a normal distribution and no major differences among genders were observed. As expected, there are differences depending on the geographical origin of the samples, reflecting different dietary habits and food sources. The intra-individual dispersion, expressed as the standard deviation (SD) of the values of the studied ERCs, did not greatly exceed the instrumental error (0.5‰), demonstrating the good preservation of the delta values along the metabolic pathway. CONCLUSIONS: For the selected ERCs of non-sporting volunteers and the urinary specimens from more than 1000 sportsmen, we can propose a maximum SD of 0.54‰ and range of 1.2‰ for delta 13 C values as acceptance criteria to detect potential outliers. These cases can be caused by the external masking effect of the administration of a substance modifying the delta values or outliers due to unforeseen procedural artifacts.


Assuntos
Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , Adulto , Anabolizantes/urina , Androsterona/análogos & derivados , Androsterona/urina , Isótopos de Carbono , Dopagem Esportivo , Etiocolanolona/análogos & derivados , Etiocolanolona/urina , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa-Espectrometria de Massas/normas , Humanos , Masculino , Espectrometria de Massas/normas , Pregnanotriol/urina , Controle de Qualidade , Padrões de Referência , Detecção do Abuso de Substâncias/normas
6.
Clin Biochem ; 55: 36-41, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29608891

RESUMO

BACKGROUND: The effects of the administration of dutasteride (DUT) on steroid metabolite pathways in BPH patients have not been examined. METHODS: Urine and blood samples as well as clinical parameters were prospectively collected after the administration of DUT to 60 BPH patients, and after its withdrawal in another set of 25 BPH patients. Urine samples were assessed using gas chromatography/mass spectrometry for the urinary steroid profile (USP), which simultaneously measures 63 steroid metabolites. We examined pharmacological changes in the 5α/5ß ratio of urinary metabolites and their relationships with clinical parameters in patients treated with DUT. RESULTS: The mean urinary androsterone/etiocholanolone (An/Et) ratio in sex-steroid pathways significantly decreased from 1.39 to 0.02 (p < 0.01). Urinary metabolites in other steroid pathways such as 5αTHF/5ßTHF in the glucocorticoid pathway and 5αTHB/5ßTHB in the mineralocorticoid pathway also significant decreased after the DUT treatment. As compared to baseline level, the mean An/Et ratios in patients with the withdrawal of DUT were 0.7%, 1.4%, 12.6%, and 82.4% at just before, one month, 3 months, and 6 months after the withdrawal of DUT, respectively. All other steroid pathways changed in a similar manner without the aggravation of urinary symptoms. The recovery ratio of An/Et in USP before and 3 months after the withdrawal of DUT correlated with the recovery ratio of serum PSA levels (ρ = 0.61, p < 0.01). CONCLUSION: Urinary 5α/5ß metabolites in all pathways were strongly suppressed after the administration of DUT for one month and the pharmacological effect of DUT prolonged even after withdrawal of DUT.


Assuntos
Androsterona/urina , Dutasterida/administração & dosagem , Etiocolanolona/urina , Cromatografia Gasosa-Espectrometria de Massas , Hiperplasia Prostática/tratamento farmacológico , Hiperplasia Prostática/urina , Adulto , Humanos , Masculino
7.
Drug Test Anal ; 8(11-12): 1204-1211, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27739243

RESUMO

Measuring carbon isotope ratios (CIRs) of urinary analytes represents a cornerstone of doping control analysis and has been particularly optimized for the detection of the misuse of endogenous steroids. Isotope ratio mass spectrometry (IRMS) of appropriate quality, however, necessitates adequate purities of the investigated steroids, which requires extensive pre-analytical sample clean-up steps due to both the natural presence of the target analytes and the high complexity of the matrix. In order to accelerate the sample preparation and increase the automation of the process, the use of multidimensional gas chromatography (MDGC) prior to IRMS experiments, was investigated. A well-established instrumental configuration based on two independent GC ovens and one heart-cutting device was optimized. The first dimension (1D) separation was obtained by a non-polar column which assured high efficiency and good loading capacity, while the second dimension (2D), based on a mid-polar stationary phase, provided good selectivity. A flame ionization detector monitored the 1D, and the 2D was simultaneously recorded by isotope ratio and quadrupole mass spectrometry. The assembled MDGC set-up was applied for measuring testosterone, 5α- and 5ß-androstanediol, androsterone, and etiocholanolone as target compounds and pregnanediol as endogenous reference compound. The urine sample were pretreated by conventional sample preparation steps comprising solid-phase extraction, hydrolysis, and liquid-liquid extraction. The extract obtained was acetylated and different aliquots were injected into the MDGC system. Two high performance liquid chromatography steps, conventionally adopted prior to CIR measurements, were replaced by the MDGC approach. The obtained values were consistent with the conventional ones. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Anabolizantes/urina , Androsterona/urina , Isótopos de Carbono/urina , Cromatografia Líquida de Alta Pressão/métodos , Etiocolanolona/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Esteroides/análise , Testosterona/urina , Anabolizantes/química , Androsterona/análise , Androsterona/química , Cromatografia Gasosa , Dopagem Esportivo , Etiocolanolona/análise , Etiocolanolona/química , Humanos , Espectrometria de Massas , Esteroides/química , Esteroides/metabolismo , Testosterona/análise
8.
Exp Gerontol ; 69: 148-58, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26079649

RESUMO

This study investigated the effects of resistance training (RT) on the metabolism of testosterone (T) in younger (n=5, 28±3yrs.) and older (n=8, 70±2yrs.) men. Experimental heavy resistance exercises (5×10RM leg presses) were performed before and after a 12-month of RT. No age differences were found in the production or metabolic clearance rate of T (determined by stable isotope dilution method), skeletal muscle androgen receptor content or serum LH concentrations due to acute or chronic RT. The T production capacity response to gonadotropin stimulation and the concentrations of the urinary T metabolites (androsterone and etiocholanolone) were lower in the older compared to younger men (p<0.05-0.01). This study further showed that RT may have acute effect on T production and clearance rates, while the exercise-induced increases in serum T appeared to be induced by decreased metabolic clearance rate of T. Attenuated T production capacity and urinary excretion of T metabolites in older men may reflect the known reduction in testicular steroidogenesis upon aging. No changes were observed in T metabolism due to RT indicating a homeostatic stability for this hormone in men of different ages.


Assuntos
Envelhecimento/fisiologia , Exercício Físico/fisiologia , Músculo Esquelético/metabolismo , Receptores Androgênicos/sangue , Treinamento Resistido/métodos , Testosterona , Adulto , Fatores Etários , Idoso , Androsterona/urina , Etiocolanolona/urina , Humanos , Marcação por Isótopo/métodos , Masculino , Avaliação de Resultados da Assistência ao Paciente , Eliminação Renal/fisiologia , Testosterona/sangue , Testosterona/metabolismo
9.
Anal Bioanal Chem ; 405(16): 5455-66, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23568614

RESUMO

Carbon isotope ratio (CIR) analysis has been routinely and successfully applied to doping control analysis for many years to uncover the misuse of endogenous steroids such as testosterone. Over the years, several challenges and limitations of this approach became apparent, e.g., the influence of inadequate chromatographic separation on CIR values or the emergence of steroid preparations comprising identical CIRs as endogenous steroids. While the latter has been addressed recently by the implementation of hydrogen isotope ratios (HIR), an improved sample preparation for CIR avoiding co-eluting compounds is presented herein together with newly established reference values of those endogenous steroids being relevant for doping controls. From the fraction of glucuronidated steroids 5ß-pregnane-3α,20α-diol, 5α-androst-16-en-3α-ol, 3α-Hydroxy-5ß-androstane-11,17-dione, 3α-hydroxy-5α-androstan-17-one (ANDRO), 3α-hydroxy-5ß-androstan-17-one (ETIO), 3ß-hydroxy-androst-5-en-17-one (DHEA), 5α- and 5ß-androstane-3α,17ß-diol (5aDIOL and 5bDIOL), 17ß-hydroxy-androst-4-en-3-one and 17α-hydroxy-androst-4-en-3-one were included. In addition, sulfate conjugates of ANDRO, ETIO, DHEA, 3ß-hydroxy-5α-androstan-17-one plus 17α- and androst-5-ene-3ß,17ß-diol were considered and analyzed after acidic solvolysis. The results obtained for the reference population encompassing n = 67 males and females confirmed earlier findings regarding factors influencing endogenous CIR. Variations in sample preparation influenced CIR measurements especially for 5aDIOL and 5bDIOL, the most valuable steroidal analytes for the detection of testosterone misuse. Earlier investigations on the HIR of the same reference population enabled the evaluation of combined measurements of CIR and HIR and its usefulness regarding both steroid metabolism studies and doping control analysis. The combination of both stable isotopes would allow for lower reference limits providing the same statistical power and certainty to distinguish between the endo- or exogenous origin of a urinary steroid.


Assuntos
Isótopos de Carbono/análise , Dopagem Esportivo/prevenção & controle , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrogênio/análise , Esteroides/urina , Administração Oral , Adulto , Androstano-3,17-diol/urina , Desidroepiandrosterona/urina , Etiocolanolona/urina , Feminino , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Esportes , Testosterona/administração & dosagem , Testosterona/análise , Testosterona/farmacologia
10.
Clin Biochem ; 46(9): 819-24, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23499585

RESUMO

OBJECTIVE: Acute intermittent porphyria (AIP) is an autosomal dominant disease that results from a deficiency of hydroxymethylbilane synthase, the third enzyme of the heme biosynthetic pathway. AIP carriers may present acute neurovisceral attacks with hepatic overproduction of heme-precursors. In some patients, remission of the acute symptoms leads to long-term hepatic metabolic abnormalities. In this study, gas chromatography-mass spectrometry (GC/MS) was used to investigate urinary steroid metabolome of AIP patients. DESIGN AND METHODS: Steroid profiling in urine was performed in a group of AIP patients with biochemically active disease (n=22) and healthy controls (n = 20). Five asymptomatic AIP family carriers were also studied. Commonly used ratios for the evaluation of disturbances in the steroid metabolism were calculated. RESULTS: We found that etiocholanolone/androsterone and tetrahydrocortisol/5α-tetrahydrocortisol (THF/5α-THF) metabolic ratios were significantly increased in the urine of AIP patients compared to controls (2.3 ± 0.3 vs 0.8 ± 0.1; p < 0.001 and 2.9 ± 0.7 vs 0.9 ± 0.1; p < 0.01). The (THF+5α-THF)/tetrahydrocortisone ratio was reduced among the AIP patients (p < 0.01). Quantification of the steroid absolute concentrations showed that these variations were due to a decrease of the 5α metabolites. Other ratios, like cortisol/cortisone and 6ß-hydroxycortisol/cortisol in the free steroid fraction did not show differences between patients and controls. All ratios were normal among the family carriers. CONCLUSION: A significant number of AIP patients present a basal decrease of steroid 5α-reductase activity in the liver. The deficiency may be related to malnutrition and hepatic energy misbalance associated with active AIP. Urinary steroid profiling by GC/MS may be a valuable tool to assess hepatic metabolome in AIP.


Assuntos
Androsterona/urina , Etiocolanolona/urina , Cromatografia Gasosa-Espectrometria de Massas/normas , Porfiria Aguda Intermitente/urina , Tetra-Hidrocortisol/análogos & derivados , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Porfiria Aguda Intermitente/diagnóstico , Padrões de Referência , Esteroides/urina , Tetra-Hidrocortisol/urina , Urinálise/normas , Adulto Jovem
11.
Drug Test Anal ; 5(7): 534-40, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23303562

RESUMO

Isotope ratio mass spectrometry (IRMS) testing is performed to determine if an atypical steroid profile is due to administration of an endogenous steroid. Androsterone (Andro) and etiocholanolone (Etio), and/or the androstanediols (5α- and 5ß-androstane-3α,17ß-diol) are typically analyzed by IRMS to determine the (13) C/(12) C ratio. The ratios of these target compounds are compared to the (13) C/(12) C ratio of an endogenous reference compound (ERC) such as 5ß-pregnane-3α,20α-diol (Pdiol). Concentrations of Andro and Etio are high so (13) C/(12) C ratios can easily be measured in most urine samples. Despite the potentially improved sensitivity of the androstanediols for detecting the use of some testosterone formulations, additional processing steps are often required that increase labour costs and turnaround times. Since this can be problematic when performing large numbers of IRMS measurements, we established thresholds for Andro and Etio that can be used to determine the need for additional androstanediol testing. Using these criteria, 105 out of 2639 urine samples exceeded the Andro and/or Etio thresholds, with 52 of these samples being positive based on Andro and Etio IRMS testing alone. The remaining 53 urine samples had androstanediol IRMS testing performed and 3 samples were positive based on the androstanediol results. A similar strategy was used to establish a threshold for Pdiol to identify athletes with relatively (13) C-depleted values so that an alternative ERC can be used to confirm or establish a true endogenous reference value. Adoption of a similar strategy by other laboratories can significantly reduce IRMS sample processing and analysis times, thereby increasing testing capacity.


Assuntos
Atletas , Isótopos de Carbono , Dopagem Esportivo , Espectrometria de Massas/métodos , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Androsterona/urina , Etiocolanolona/urina , Humanos , Espectrometria de Massas/normas , Detecção do Abuso de Substâncias/normas
12.
Steroids ; 77(11): 1050-60, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22728892

RESUMO

In doping control, an athlete can only be convicted with the misuse with endogenous steroids like testosterone (T), if abnormal values of steroid metabolites and steroid ratios are observed and if the subsequent analysis with isotope ratios mass spectrometry (IRMS) confirms the presence of exogenously administered androgens. In this work, we compare the results of a novel steroid profiling approach with the performance an in-house developed IRMS method. The developed IRMS has the advantage over other methods to be relatively short in time and with target compounds androsterone, etiocholanolone, 5ß-androstane 3α,17ß-diol and 5α-androstane 3α,17ß-diol. Pregnanediol was used as an endogenous reference compound (ERC). Reference limits for the IRMS values were established and applied as decision limits for the evaluation of excretion urine from administration with oral T, T-gel, dihydrotestosterone (DHT) - gel and dehydroepiandrosterone (DHEA). Results indicated the importance of both androstanediols as important IRMS markers where relative values compared to an ERC (Δδ(13)C) yielded better detection accuracy than absolute δ(13)C-values. The detection times of all administered endogenous steroids were evaluated using the proposed thresholds. The results of traditional steroid profiling and a new approach based upon minor steroid metabolites monitoring introduced in a longitudinal framework were evaluated with IRMS. With traditional steroid profiling methods, 95% of the atypical samples could be confirmed whereas an additional 74% of IRMS confirmed was provided by a new biomarkers strategy. These results prove that the other steroid profiling strategies can improve the efficiency in detection of misuse with endogenous steroids.


Assuntos
Androstano-3,17-diol/urina , Androsterona/urina , Dopagem Esportivo , Etiocolanolona/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , Adulto , Isótopos de Carbono , Cromatografia Líquida de Alta Pressão , Desidroepiandrosterona/administração & dosagem , Desidroepiandrosterona/urina , Di-Hidrotestosterona/administração & dosagem , Di-Hidrotestosterona/urina , Feminino , Humanos , Masculino , Pregnanodiol/urina , Padrões de Referência , Valores de Referência , Estereoisomerismo
13.
Drug Test Anal ; 4(12): 928-33, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22544546

RESUMO

An accurate method for the measurement of carbon isotope ratios of steroids in human urine has been developed at the National Measurement Institute, Australia (NMIA) for the certification of a freeze-dried human urine reference material (CRM NMIA MX005). The method measures δ(13)C values by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) analysis following hydrolysis, solvent extraction and high performance liquid chromatography (HPLC) purification. Reference δ(13)C values for testosterone metabolites etiocholanolone, androsterone, and endogenous reference compounds (ERCs) 11ß-hydroxyandrosterone and pregnanediol were determined, as well as information δ(13)C values for testosterone, epitestosterone, 11-oxoetiocholanolone, and a range of differences (Δ(13)C) between testosterone metabolites and ERCs. The measurement uncertainty was rigorously evaluated with expanded uncertainties for the reference δ(13)C values between 1.1 and 1.6 ‰ at the 95% coverage level.


Assuntos
Anabolizantes/urina , Isótopos de Carbono/urina , Certificação/normas , Dopagem Esportivo , Liofilização/normas , Cromatografia Gasosa-Espectrometria de Massas/normas , Substâncias para Melhoria do Desempenho/urina , Detecção do Abuso de Substâncias/normas , Testosterona/urina , Androsterona/análogos & derivados , Androsterona/urina , Austrália , Biomarcadores/urina , Biotransformação , Calibragem , Cromatografia Líquida de Alta Pressão , Etiocolanolona/urina , Humanos , Hidrólise , Valor Preditivo dos Testes , Pregnanodiol/urina , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Solventes/química , Detecção do Abuso de Substâncias/métodos , Incerteza
14.
Acta Obstet Gynecol Scand ; 91(5): 625-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22375705

RESUMO

OBJECTIVE: The aim of the study was to compare the levels of urinary steroid metabolites of patients with successful in vitro fertilization and patients who failed to achieve pregnancy. DESIGN: Comparison of urinary steroid profiles prior to oocyte pick-up and three weeks after embryo transfer. SETTING: University hospital. SAMPLE: Eleven women in the same age range with pregnancy after in vitro fertilization and eleven women who failed to achieve pregnancy. METHODS: The standard "long" protocol was used for ovarian stimulation and intracytoplasmic sperm injection for assisted in vitro fertilization. The steroid metabolites in urine samples collected for 24 h were determined by gas chromatography-mass spectrometry. MAIN OUTCOME MEASURES: Steroid metabolite levels in urine samples determined in the early pregnancy period. RESULTS: The levels of androsterone, etiocholanolone, pregnanediol, tetrahydro-11-dehydrocorticosterone and tetrahydro-corticosterone were significantly higher (p < 0.05) in the urine of women with successful pregnancy three weeks after the embryo transfer, while the levels of tetrahydrocortisone, tetrahydrocortisol, allo-tetrahydrocortisol and α-cortolone became higher in the group of patients with unsuccessful pregnancy. CONCLUSIONS: The production of androgens, progesterone and corticoid steroid metabolites is altered in the early pregnancy period after in vitro fertilization.


Assuntos
Androsterona/urina , Corticosterona/análogos & derivados , Etiocolanolona/urina , Fertilização in vitro , Primeiro Trimestre da Gravidez/urina , Pregnanodiol/urina , Adulto , Corticosterona/urina , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Indução da Ovulação , Gravidez , Resultado da Gravidez , Injeções de Esperma Intracitoplásmicas
15.
Anal Chem ; 83(18): 7158-65, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21846122

RESUMO

We report the first demonstration of comprehensive two-dimensional gas chromatography combustion-isotope ratio mass spectrometry (GC×GCC-IRMS) for the analysis of urinary steroids to detect illicit synthetic testosterone use, of interest in sport doping. GC coupled to IRMS (GCC-IRMS) is currently used to measure the carbon isotope ratios (CIRs, δ(13)C) of urinary steroids in antidoping efforts; however, extensive cleanup of urine extracts is required prior to analysis to enable baseline separation of target steroids. With its greater separation capabilities, GC×GC has the potential to reduce sample preparation requirements and enable CIR analysis of minimally processed urine extracts. Challenges addressed include online reactors with minimized dimensions to retain narrow peak shapes, baseline separation of peaks in some cases, and reconstruction of isotopic information from sliced steroid chromatographic peaks. Difficulties remaining include long-term robustness of online reactors and urine matrix effects that preclude baseline separation and isotopic analysis of low-concentration and trace components. In this work, steroids were extracted, acetylated, and analyzed using a refined, home-built GC×GCC-IRMS system. 11-Hydroxyandrosterone and 11-ketoetiocolanolone were chosen as endogenous reference compounds because of their satisfactory signal intensity, and their CIR was compared to target compounds androsterone and etiocholanolone. Separately, a GC×GC-quadrupole MS system was used to measure testosterone (T)/epitestosterone (EpiT) concentration ratios. Urinary extracts of urine pooled from professional athletes and urine from one individual that received testosterone gel (T-gel) and one individual that received testosterone injections (T-shots) were analyzed. The average precisions of δ(13)C and Δδ(13)C measurements were SD(δ(13)C) approximately ±1‰ (n = 11). The T-shot sample resulted in a positive for T use with a T/EpiT ratio of >9 and CIR measurements of Δδ(13)C > 5‰, both fulfilling World Anti-Doping Agency criteria. These data show for the first time that synthetic steroid use is detectable by GC×GCC-IRMS without the need for extensive urine cleanup.


Assuntos
Dopagem Esportivo/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Testosterona/urina , Isótopos de Carbono/química , Epitestosterona/urina , Etiocolanolona/análogos & derivados , Etiocolanolona/normas , Etiocolanolona/urina , Cromatografia Gasosa-Espectrometria de Massas/normas , Humanos , Marcação por Isótopo , Padrões de Referência
16.
Acta Paediatr ; 100(12): e280-2, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21535128

RESUMO

AIM: To analyse the urinary steroid metabolome in a boy who had true precocious puberty after a Leydig cell tumour. METHOD: Case report and detailed description of clinical and metabolic findings in a 7-year-old-boy with a Leydig cell tumour. RESULTS: Before surgery, the urinary steroid metabolome showed an activation of an alternative route to gonadal androgens independent of dehydroepiandrosterone (DHEA). After surgery, the boy entered true precocious puberty. Under leuprolide acetate treatment, clinical and laboratory findings normalized. CONCLUSION: Central precocious puberty after precocious pseudopuberty may be more common than expected and should be considered in children with persistent or recurrent symptoms after initial treatment of precocious pseudopuberty. Patients with a Leydig cell tumour seem to reactivate the so-called 'back door pathway' of androgen production, which is independent of the classical route via DHEA.


Assuntos
Leuprolida/uso terapêutico , Tumor de Células de Leydig/urina , Puberdade Precoce/tratamento farmacológico , Neoplasias Testiculares/urina , Androsterona/urina , Antineoplásicos Hormonais/uso terapêutico , Criança , Desidroepiandrosterona/urina , Etiocolanolona/urina , Humanos , Tumor de Células de Leydig/metabolismo , Tumor de Células de Leydig/cirurgia , Masculino , Metaboloma/fisiologia , Pregnanolona/urina , Puberdade Precoce/etiologia , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/cirurgia , Testosterona/urina
17.
Am J Clin Nutr ; 93(5): 911-7, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21367953

RESUMO

BACKGROUND: To our knowledge, changes in steroid metabolism in subjects with anorexia nervosa (AN) after weight gain have not been elucidated. OBJECTIVE: We characterized urinary steroid excretion and metabolism in AN patients and investigated the effects of refeeding. DESIGN: In an intervention study, we recruited 7 women with life-threatening weight loss upon admission and after a median [interquartile range (IQR)] of 95 d (88-125 d) of intensive refeeding; 15 age-matched women were recruited as control subjects. The major urinary metabolites were quantified in 24-h collections by capillary gas chromatography. A single examiner measured weights, heights, and skinfold thicknesses. RESULTS: The median (IQR) age of patients was 24 y (21-26 y), and the duration of AN was 4.0 y (3.3-8.0 y). Body mass index (BMI; in kg/m(2)) increased from 12.8 (12.7-13.1) to 18.6 (18.0-19.6) after refeeding (P < 0.0001). Steroid values [median pre-, post-refeeding (P value)] were as follows: androgen metabolites [472, 1017 µg/24 h (0.93)], cortisol metabolites [1960, 3912 µg/24 h (0.60)], and ratios of androsterone (5α)/etiocholanolone (5ß) [0.28, 0.63 (<0.001)], 5α-/5ß-tetrahydrocortisol [0.20, 0.48 (0.02)], tetrahydrocortisols/tetrahydrocortisone [0.87, 0.61 (0.09)], 20-hydroxy-/20-oxocortisol metabolites [0.29, 0.47 (0.01)], and 20α-/20ß-reduced cortisol metabolites [1.18, 1.89 (≥1.00)]. BMI change was positively correlated with 5α-/5ß-tetrahydrocortisol (r = 0.95, P < 0.001). Before refeeding, the following metabolites were lower in patients than in control subjects: androsterone, 5α-tetrahydrocortisol, α-cortolone and α-cortol, 5α-/5ß-tetrahydrocortisol, androsterone/etiocholanolone, and 20-hydroxy/20-oxocortisol (all P < 0.05). After refeeding, all steroid metabolites in patients were at concentrations that were comparable with those in control subjects. CONCLUSIONS: Significant changes in urine steroid-metabolite excretion occurred upon starvation, which were reversed upon refeeding. For cortisol, there were decreases in 5α-/5ß-tetrahydrocortisol and 20-hydroxy-/20-oxometabolites; for androgen, there was a decrease in androsterone/etiocholanolone.


Assuntos
Androgênios/metabolismo , Androgênios/urina , Anorexia Nervosa/dietoterapia , Anorexia Nervosa/urina , Dieta , Hidrocortisona/metabolismo , Hidrocortisona/urina , Adulto , Algoritmos , Androsterona/urina , Anorexia Nervosa/metabolismo , Índice de Massa Corporal , Etiocolanolona/urina , Feminino , Humanos , Hidrocortisona/análogos & derivados , Isomerismo , Tetra-Hidrocortisol/urina , Adulto Jovem
18.
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
19.
Anal Chim Acta ; 683(2): 221-6, 2011 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-21167974

RESUMO

The presence of microorganisms in urine samples, under favourable conditions of storage and transportation, may alter the concentration of steroid hormones, thus altering the correct evaluation of the urinary steroid profile in doping control analysis. According to the rules of the World Anti-Doping Agency (WADA technical document TD2004 EAAS), a testosterone deconjugation higher than 5% and the presence of 5α-androstane-3,17-dione and 5ß-androstane-3,17-dione in the deconjugated fraction, are reliable indicators of urine degradation. The determination of these markers would require an additional quantitative analysis since the steroids screening analysis, in anti-doping laboratories, is performed in the total (free+conjugated) fraction. The aim of this work is therefore to establish reliable threshold values for some representative compounds (namely 5α-androstane-3,17-dione and 5ß-androstane-3,17-dione) in the total fraction in order to predict directly at the screening stage the potential microbial degradation of the urine samples. Preliminary evidence on the most suitable degradation indexes has been obtained by measuring the urinary concentration of testosterone, epitestosterone, 5α-androstane-3,17-dione and 5ß-androstane-3,17-dione by gas chromatography-mass spectrometric every day for 15 days in the deconjugated, glucuronide and total fraction of 10 pools of urines from 60 healthy subjects, stored under different pH and temperature conditions, and isolating the samples with one or more markers of degradation according to the WADA technical document TD2004EAAS. The threshold values for 5α-androstane-3,17-dione and 5ß-androstane-3,17-dione were therefore obtained correlating the testosterone deconjugation rate with the urinary concentrations of 5α-androstane-3,17-dione and 5ß-androstane-3,17-dione in the total fraction. The threshold values suggested as indexes of urine degradation in the total fraction were: 10 ng mL(-1) for 5α-androstane-3,17-dione and 20 ng mL(-1) for 5ß-androstane-3,17-dione. The validity of this approach was confirmed by the analysis of routine samples for more than five months (i.e. on a total of more than 4000 urine samples): samples with a concentration of total 5α-androstane-3,17-dione and 5ß-androstane-3,17-dione higher than the threshold values showed a percentage of free testosterone higher than 5 of its total amount; whereas free testosterone in a percentage higher than 5 of its total amount was not detected in urines with a concentration of total 5α-androstane-3,17-dione and 5ß-androstane-3,17-dione lower than the threshold values.


Assuntos
Epitestosterona/urina , Etiocolanolona/análogos & derivados , Cromatografia Gasosa-Espectrometria de Massas/métodos , Testosterona/urina , Dopagem Esportivo , Etiocolanolona/urina , Glucuronídeos/química , Humanos , Concentração de Íons de Hidrogênio , Temperatura , Fatores de Tempo
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