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1.
Drug Test Anal ; 14(5): 851-863, 2022 May.
Article in English | MEDLINE | ID: mdl-33982451

ABSTRACT

The most frequently detected substances prohibited by the World Anti-Doping Agency (WADA) belong to the anabolic steroids class. The most challenging compounds among this class are the endogenous anabolic steroids, which are detected by quantitative measurement of testosterone (T) and its metabolites with a so-called "steroid profiling" method. The current steroid profile is based on the concentrations and ratios of the sum of free and glucuronidated steroids. Recently, our group developed a steroid profiling method for the detection of three free steroids and 14 intact steroid conjugates, including both the glucuronic acid conjugated and sulfated fraction. The study aimed at evaluating the long-term stability of steroid conjugate concentrations and ratios, and the influence of different endogenous steroids on this extended steroid profile. A single dose of oral T undecanoate (TU), topical T gel, topical dihydrotestosterone (DHT) gel, and oral dehydroepiandrosterone (DHEA) was administered to six healthy male volunteers. One additional volunteer with a homozygote deletion of the UGT2B17 gene (del/del genotype) received a single topical dose of T gel. An intramuscular dose of TU was administered to another volunteer. To avoid fluctuation of steroid concentrations caused by variations in urinary flow rates, steroid ratios were calculated and evaluated as possible biomarkers for the detection of endogenous steroid abuse with low doses. Overall, sulfates do not have substantial additional value in prolonging detection times for the investigated endogenous steroids and administration doses. The already monitored glucuronides were overall the best markers and were sufficient to detect the administered steroids.


Subject(s)
Doping in Sports , Dihydrotestosterone/metabolism , Humans , Male , Steroids , Substance Abuse Detection/methods , Sulfates , Testosterone/metabolism , Testosterone Congeners
2.
J Steroid Biochem Mol Biol ; 209: 105851, 2021 05.
Article in English | MEDLINE | ID: mdl-33610798

ABSTRACT

OBJECTIVE: Men with obesity often have low total and, with increasing adiposity, also low free testosterone (T) levels, which can partially restore during weight loss. Although this is partly explained by lower sex hormone binding globulin (SHBG) production and hypothalamic-pituitary downregulation, it is still not unravelled whether changes in androgen metabolism contribute to this phenomenon. Therefore, early changes in urinary excretion of T and its metabolites, during weight loss, in men with obesity are investigated. DESIGN: Longitudinal study. METHODS: Fourteen men with obesity (age 52(45-60)years, BMI 42.6(41.8-44.8)kg/m²) underwent gastric bypass surgery (GBS). Before surgery and 3 weeks, 6 weeks, 6 months and 1 year thereafter, 24 h urine and fasting serum samples were collected. Serum T and estradiol (E2) levels were analyzed using LC-MS/MS and urinary metabolites of T with GC-MS/MS. RESULTS: Already three weeks after GBS, serum SHBG and total T levels increased and remained increased as compared to baseline (all,p < 0.0125). Gonadotropins and (free) E2 levels were unchanged, serum E2/T ratio decreased (p < 0.0125). Total amount of urinary T increased non-significantly with mean increases of 53 % one year after GBS (p = 0.026). Urinary E2/T, estrone/T, 3α-androstanediol/T and androsterone/T ratios decreased after GBS (p < 0.0125). CONCLUSIONS: Restoration of circulating T levels during weight loss in this population is not only brought about by normalization of circulating SHBG levels, but increased production of and alterations in T metabolism also contribute. More specifically, relative decreases in aromatization and lower 5α-reductase activity might also be involved in restoring T levels in men with obesity.


Subject(s)
Hydroxysteroid Dehydrogenases/metabolism , Obesity/metabolism , Sex Hormone-Binding Globulin/metabolism , Testosterone/metabolism , Weight Loss , Humans , Hydroxysteroid Dehydrogenases/genetics , Longitudinal Studies , Male , Middle Aged , Obesity/pathology , Prospective Studies
4.
Clin Chim Acta ; 510: 391-399, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32739215

ABSTRACT

Quantification of IGF-I is relevant in both doping control as a biomarker of growth hormone (GH) misuse in sports, and in the clinical field for longitudinal follow-up of patients with disorders related to the GH axis. Currently, better standardization of IGF-I measurements using mass spectrometry is in our best interest as it would enable long-term monitoring of an athletes' IGF-I levels by its addition to the Athlete Biological Passport (ABP). Here, a simplified and rapid top-down LC-HRMS method for quantification of IGF-I in human serum is presented. A ten-minute precipitation-based offline sample preparation is combined with online sample clean-up and separation on a conventional LC, resulting in a total runtime of nine minutes in between injections. The method was validated in the relevant range of 50-1000 ng/mL for the following parameters: linearity, precision, bias, Limit Of Quantification (LOQ), carry-over, selectivity, recovery and ion suppression. As proof of concept, the presented LC-HRMS assay was compared with results from a previous inter-laboratory study on intact IGF-I quantification using four human GH administration samples. It was additionally compared with the IDS-iSYS immunoassay using 47 athlete serum samples, showing good overall agreement with a slight positive bias of 24.2 ng/mL for the LC-HRMS assay at a mean sample concentration of 234 ng/mL. Also, a discrepancy between commercially available IGF-I reference material for the calibration of quantitative assays is discussed. This is of importance if LC-MS assays for IGF-I are to be harmonized.


Subject(s)
Human Growth Hormone , Insulin-Like Growth Factor I , Chromatography, Liquid , Humans , Immunoassay , Tandem Mass Spectrometry
5.
J Chromatogr A ; 1624: 461231, 2020 Aug 02.
Article in English | MEDLINE | ID: mdl-32540072

ABSTRACT

Detection of endogenous anabolic androgenic steroids (EAAS) misuse is a major challenge in doping control analysis. Currently, a number of endogenous steroids, which constitute the steroid profile, are quantified using gas chromatography (GC). With this methodology, only the sum of the free and glucuronidated steroids is measured together. A dilute-and-shoot LC-MS method, which is compliant with the quality requirements for measuring EAAS established by the World Anti-Doping Agency (WADA), was developed and validated containing glucuronidated and sulfated steroids in order to gain some extra information and to expand the existing steroid profile. The developed method is, to the best of our knowledge, the first method to combine both steroid glucuronides and sulfates, which is compliant with the quality standards of the technical document on EAAS, established by WADA. The first advantage of this new steroid profile is the reduced sample preparation time, as it is a direct injection method of diluted urine. A second advantage is the ability of the used gradient to separate 5α-androstane-3α,17ß-diol-3-glucuronide (5ααßdiol3G), 5α-androstane-3α,17ß-diol-17-glucuronide (5ααßdiol17G), 5ß-androstane-3α,17ß-diol-3-glucuronide (5ßαßdiol3G) and 5ß-androstane-3α,17ß-diol-17-glucuronide (5ßαßdiol17G) allowing to gain specific information on these isomers, which cannot be accomplished in GC-MS screening due to hydrolysis. This steroid profile also contains free testosterone, 5α-androstane-3,17-dione and 5ß-androstane-3,17-dione as markers of degradation. In total, 17 compounds and 10 isotopically labelled internal standards are included in this method.


Subject(s)
Steroids/urine , Chromatography, High Pressure Liquid , Doping in Sports , Glucuronides/analysis , Glucuronides/chemistry , Glucuronides/urine , Humans , Mass Spectrometry , Steroids/chemistry
6.
Drug Test Anal ; 12(8): 1006-1018, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32267625

ABSTRACT

In doping control, to confirm the exogenous origin of exogenously administered anabolic androgenic steroids (AAS), a gas chromatography combustion isotope ratio mass spectrometry (GC-C-IRMS) analysis is performed. Recently published work suggests that epiandrosterone sulfate (EpiAS) is a promising IRMS target compound for the detection of AAS, capable of prolonging the detection window. However, EpiAS is only excreted in urine in its sulfoconjugated form, while all other IRMS target compounds are excreted glucuronidated, meaning that EpiAS cannot be incorporated in the existing IRMS methods. A separate extensive sample preparation needs to be performed on this compound with a different hydrolysis and extraction procedure and a different liquid chromatography (LC) clean-up. The current work presents a new, fast, and easy to implement EpiAS IRMS method. The approach was based on the direct GC analysis of non-hydrolyzed EpiAS, making the solid phase extraction, hydrolysis, and acetylation step redundant. Sample preparation consisted of a simple liquid-liquid extraction, followed by LC fraction collection. A population study was performed to check compliance with the criteria drafted by the World Anti-Doping Agency (WADA). To verify the applicability of the developed approach, the method was applied to the samples of four administration studies (i.e. dehydroepiandrosterone (DHEA), testosterone gel (T gel), androstenedione (ADION), and intramuscular testosterone undecanoate. In contrast to previously published data, the strength of EpiAS as the target compound and the prolongation of the detection window in comparison with the conventional IRMS target compounds was less pronounced.


Subject(s)
Androsterone/analogs & derivatives , Gas Chromatography-Mass Spectrometry/methods , Substance Abuse Detection/methods , Adult , Androsterone/urine , Chromatography, Liquid/methods , Doping in Sports/prevention & control , Female , Humans , Male , Young Adult
7.
Article in English | MEDLINE | ID: mdl-32109748

ABSTRACT

The standard approach to detect misuse with testosterone in sport is based on the determination and evaluation of the urinary steroid profile followed by the confirmation of atypical profiles using isotope ratio mass spectrometry. The detection capacity of these methods can be attenuated by confounding factors or testosterone preparations with endogenous isotopic fingerprints. An alternative detection method for misuse of an endogenous steroid in sports is the direct detection of the administered steroid ester present in most preparations. Thus unambiguous proof for doping misuse can be delivered. In this work, the sensitivity of gas chromatography coupled to a triple quadrupole with chemical ionization (GC-CI-MS/MS) is applied to detect trace levels of 10 testosterone and 2 nandrolone esters in plasma for in human doping analysis. The detection method was developed employing a liquid-liquid extraction and HPLC cleanup step before analysis on the GC-CI-MS/MS. The quantitative method was validated in a linear range of 100-2000 pg/ml and proved to be selective, reproducible and very sensitive with limits of detection as low as to 10 pg/ml. A clinical study with the administration of testosterone undecanoate in 3 volunteers was carried out and the compound was detectable up to 86 days after administration.


Subject(s)
Doping in Sports , Gas Chromatography-Mass Spectrometry/methods , Steroids/blood , Tandem Mass Spectrometry/methods , Esters , Humans , Linear Models , Liquid-Liquid Extraction , Male , Reproducibility of Results , Sensitivity and Specificity , Steroids/chemistry , Steroids/isolation & purification , Testosterone/analogs & derivatives , Testosterone/blood
8.
Anal Chim Acta ; 999: 1-12, 2018 Jan 25.
Article in English | MEDLINE | ID: mdl-29254559

ABSTRACT

Urine and blood samples are the primary matrices for the detection of exogenous substances in doping control and toxicology. Although these matrices are, in general, very suitable for a wide range of substances, they do show some issues in particular cases. Here, alternative matrices may provide an answer. In this work, a quantitative method for steroid profiling (5 endogenous steroids and their ratios) in oral fluid was developed and validated. In total, 826 saliva samples were analyzed, and inter-individual reference population thresholds for saliva steroid profile parameters were set up. Alterations of this steroid profile after administration of naturally occurring anabolic androgenic steroids (e.g. testosterone (T) or dehydroepiandrosterone (DHEA)) were investigated. In addition, intra-individual short and long-term natural fluctuations were investigated. For longitudinal monitoring in oral fluid, steroid profile ratios (e.g., T/DHEA) were superior to absolute concentrations due to lower susceptibility towards the diurnal pattern. For the detection of a transdermal application of T, the salivary parameter T/DHEA proved to have the highest sensitivity. In contrast with the current screening procedures in urine, there is no need for an additional expensive and time-consuming isotope ratio mass spectrometry confirmation procedure to unequivocally attribute the elevated parameter to an exogenous origin.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Saliva/chemistry , Steroids/analysis , Substance Abuse Detection/methods , Female , Gas Chromatography-Mass Spectrometry/standards , Humans , Limit of Detection , Male , Reference Standards , Steroids/urine , Substance Abuse Detection/standards
9.
Drug Test Anal ; 6(10): 978-84, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24515835

ABSTRACT

Recent publications have shown that the concentrations of minor metabolites such as formestane and 6a-hydroxy-androstenedione (6aOHADION) are import parameters, capable of increasing the specificity and efficiency of steroid abuse screening. The importance of such minor metabolites has been recognized for some time, but setting up concentration thresholds is not that straightforward with a single quadrupole gas chromatograph mass spectrometer (GC-MS) because of the low concentrations; this is especially the case for 6aOH-ADION. The main aim of this study was to propose a concentration threshold above which the detected 6aOH-ADION is considered suspicious and isotope ratio mass spectrometry (IRMS) is recommended. Routine doping control samples (2128) from athletes that entered our lab and were not found suspicious for the intake of any doping substance were used to determine the baseline concentrations of 6a-OH-ADION. For this purpose, the more sensitive gas chromatography-tandem mass spectrometry (GC-MS/MS) was used, capable of quantifying these low concentrations with high reliability. A urinary concentration threshold of 5 ng/mL was set. Concentrations above this threshold are considered suspicious and are forwarded to IRMS for confirmation in routine practice. In addition, an IRMS method was developed, capable of determining the 13C value of 6aOH-ADION. If a urine sample has an elevated 6aOH-ADION concentration and normal 13C values for the traditional IRMS target compounds, we are still able to check the 13C value of 6aOH-ADION. Six excretion studies were executed to stress the applicability of the threshold by visualizing the concentration and δ13C value time profiles of 6aOH-ADION.


Subject(s)
Anabolic Agents/metabolism , Androstenedione/analogs & derivatives , Doping in Sports/prevention & control , Substance Abuse Detection/methods , Adult , Anabolic Agents/analysis , Androgens/analysis , Androgens/metabolism , Androstenedione/analysis , Androstenedione/metabolism , Gas Chromatography-Mass Spectrometry/methods , Humans , Male , Reproducibility of Results , Tandem Mass Spectrometry/methods , Young Adult
10.
Steroids ; 78(11): 1103-9, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23933120

ABSTRACT

Formestane (F, androst-4-en-4-ol-3,17-dione) is an irreversible aromatase inhibitor with the ability to suppress the estrogen production from anabolic steroids. Consequently, F is mentioned on the World Anti-Doping Agency (WADA) prohibited list and because studies have shown that F is produced endogenously in small amounts, a threshold for urinary excreted F of 150 ng/mL was introduced. Lower concentrations could be due to endogenous production and need further investigation to prove the exact origin through determination of the carbon isotope ratio. However, because the current screening methods are a lot more sensitive, F is detected in practically every urine sample. A strict implementation of this WADA rule would imply that almost every urine sample needs additional investigation to verify an exogenous or endogenous origin. The main aim of this study was to propose and introduce a lower concentration limit of 25 ng/mL beneath which the detected F is considered as being endogenous and no further investigation is needed. The data presented in this paper suggests that this threshold provides a good balance between a sufficiently large detection window and not having to perform isotope ratio mass spectrometry (IRMS) analyses on negative urine samples.


Subject(s)
Androstenedione/analogs & derivatives , Mass Spectrometry/methods , Urinalysis/methods , Adult , Androstenedione/urine , Carbon Isotopes/chemistry , Doping in Sports/prevention & control , Female , Humans , Limit of Detection , Male , Reproducibility of Results , Young Adult
11.
Anal Chim Acta ; 768: 41-8, 2013 Mar 20.
Article in English | MEDLINE | ID: mdl-23473248

ABSTRACT

Due to their performance enhancing properties, use of anabolic steroids (e.g. testosterone, nandrolone, etc.) is banned in elite sports. Therefore, doping control laboratories accredited by the World Anti-Doping Agency (WADA) screen among others for these prohibited substances in urine. It is particularly challenging to detect misuse with naturally occurring anabolic steroids such as testosterone (T), which is a popular ergogenic agent in sports and society. To screen for misuse with these compounds, drug testing laboratories monitor the urinary concentrations of endogenous steroid metabolites and their ratios, which constitute the steroid profile and compare them with reference ranges to detect unnaturally high values. However, the interpretation of the steroid profile is difficult due to large inter-individual variances, various confounding factors and different endogenous steroids marketed that influence the steroid profile in various ways. A support vector machine (SVM) algorithm was developed to statistically evaluate urinary steroid profiles composed of an extended range of steroid profile metabolites. This model makes the interpretation of the analytical data in the quest for deviating steroid profiles feasible and shows its versatility towards different kinds of misused endogenous steroids. The SVM model outperforms the current biomarkers with respect to detection sensitivity and accuracy, particularly when it is coupled to individual data as stored in the Athlete Biological Passport.


Subject(s)
Gas Chromatography-Mass Spectrometry , Steroids/urine , Support Vector Machine , Doping in Sports , Humans , Male , Nandrolone/analysis , ROC Curve , Testosterone/analysis
12.
Steroids ; 77(11): 1050-60, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22728892

ABSTRACT

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.


Subject(s)
Androstane-3,17-diol/urine , Androsterone/urine , Doping in Sports , Etiocholanolone/urine , Gas Chromatography-Mass Spectrometry/methods , Substance Abuse Detection/methods , Adult , Carbon Isotopes , Chromatography, High Pressure Liquid , Dehydroepiandrosterone/administration & dosage , Dehydroepiandrosterone/urine , Dihydrotestosterone/administration & dosage , Dihydrotestosterone/urine , Female , Humans , Male , Pregnanediol/urine , Reference Standards , Reference Values , Stereoisomerism
13.
Drug Test Anal ; 3(11-12): 828-35, 2011.
Article in English | MEDLINE | ID: mdl-21998068

ABSTRACT

The natural occurrence of endogenous anabolic steroids together with their availability in different administration forms makes the detection of their misuse a great challenge for doping control laboratories. Nowadays, the detection of endogenous steroids abuse is performed by the analysis of the steroid profile. Recently, androst-1,4-dien-3,17-dione (1,4-AD), androst-4,6-dien-3,17-dione (4,6-AD), 17ß-hydroxy-androst-4,6-dien-3-one (6-T), and androst-15-en-3,17-dione (15-AD) have been described as testosterone (T) metabolites released after basic treatment of the urine. In the present work, the usefulness of these metabolites has been evaluated detecting the use of three different forms of endogenous steroids in a single dose: dihydrotestosterone gel (DHT), oral dehydroepiandrosterone (DHEA), and T gel. After the independent administration of these endogenous steroids, a rise in the value of several of the ratios calculated between the tested metabolites was noticed. For DHT, a small increase was observed for the ratios 1,4-AD/15-AD, 6-T/15-AD and 4,6-AD/15-AD although only for one volunteer. Better results were obtained for oral DHEA and T gel where an increase was observed in all volunteers for several of the tested ratios. The detection time in which the misuse can be detected (DT) has been evaluated using two different approaches: (1) comparison with population based reference limits, and (2) comparison with individual threshold levels. The obtained DTs were compared with the results of previously published markers for the misuse of such substances. When using basic released metabolites, shorter DTs were obtained for DHT, similar DTs for DHEA, and the detectability was substantially improved for T gel.


Subject(s)
Dehydroepiandrosterone/metabolism , Dehydroepiandrosterone/urine , Dihydrotestosterone/metabolism , Dihydrotestosterone/urine , Substance Abuse Detection/methods , Testosterone/metabolism , Testosterone/urine , Administration, Oral , Administration, Topical , Adult , Dehydroepiandrosterone/administration & dosage , Dihydrotestosterone/administration & dosage , Doping in Sports , Gas Chromatography-Mass Spectrometry/methods , Humans , Male , Sensitivity and Specificity , Testosterone/administration & dosage , Young Adult
14.
Clin Endocrinol (Oxf) ; 75(1): 134-40, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21521264

ABSTRACT

CONTEXT: Until now, the testosterone/epitestosterone (T/E) ratio is the main marker for the detection of testosterone (T) misuse in athletes. As this marker can be influenced by a number of confounding factors, additional steroid profile parameters indicating T misuse can provide substantiating evidence of doping with endogenous steroids. The evaluation of a steroid profile is currently based upon population statistics. As large inter-individual variations exist, a paradigm shift towards subject-based references is ongoing in doping analysis. OBJECTIVE: Proposition of new biomarkers for the detection of testosterone in sports using extensive steroid profiling and an adaptive model based upon Bayesian inference. SUBJECTS: Six healthy male volunteers were administered with testosterone undecanoate. Population statistics were performed upon steroid profiles from 2014 male Caucasian athletes participating in official sport competition. DESIGN: An extended search for new biomarkers in a comprehensive steroid profile combined with Bayesian inference techniques as used in the athlete biological passport resulted in a selection of additional biomarkers that may improve detection of testosterone misuse in sports. RESULTS: Apart from T/E, 4 other steroid ratios (6α-OH-androstenedione/16α-OH-dehydroepiandrostenedione, 4-OH-androstenedione/16α-OH-androstenedione, 7α-OH-testosterone/7ß-OH-dehydro-epiandrostenedione and dihydrotestosterone/5ß-androstane-3α,17ß-diol) were identified as sensitive urinary biomarkers for T misuse. These new biomarkers were rated according to relative response, parameter stability, detection time and discriminative power. CONCLUSION: Newly selected biomarkers were found suitable for individual referencing within the concept of the Athlete's Biological Passport. The parameters showed improved detection time and discriminative power compared to the T/E ratio. Such biomarkers can support the evidence of doping with small oral doses of testosterone.


Subject(s)
Androgens/urine , Androstanes/urine , Biomarkers/urine , Substance Abuse Detection/methods , Adult , Androgens/administration & dosage , Androgens/pharmacology , Doping in Sports/prevention & control , Humans , Male , Pilot Projects , Reference Values , Testosterone/administration & dosage , Testosterone/analogs & derivatives , Testosterone/pharmacology , Young Adult
15.
Steroids ; 75(13-14): 1047-57, 2010 Dec 12.
Article in English | MEDLINE | ID: mdl-20688095

ABSTRACT

Steroid profiling provides valuable information to detect doping with endogenous steroids. Apart from the traditionally monitored steroids, minor metabolites can play an important role to increase the specificity and efficiency of current detection methods. The applicability of several minor steroid metabolites was tested on administration studies with low doses of oral testosterone (T), T gel, dihydrotestosterone (DHT) gel and oral dehydroepiandrosterone (DHEA). The collected data for all monitored parameters were evaluated with the respective population based reference ranges. Besides the traditional markers T/E, T and DHT, minor metabolites 4-OH-Adion and 6α-OH-Adion were found as most sensitive metabolites to detect oral T administration. The most sensitive metabolites for the detection of DHEA were identified as 16α-OH-DHEA and 7ß-OH-DHEA but longest detection up to three days (after oral administration of 50 mg) was obtained with non-specific 5ß-steroids and its ratios. Steroids applied as a gel had longer effects on the metabolism but were generally not detectable with universal decision criteria. It can be concluded that population based reference ranges show limited overall performance in detecting misuse of small doses of natural androgens. Although some minor metabolites provide additional information for the oral testosterone and DHEA formulations, the topical administered steroids could not be detected for all volunteers using universal reference limits. Application of other population based threshold limits did not lead to longer detection times.


Subject(s)
Androstenols/administration & dosage , Androstenols/urine , Urinalysis/standards , Administration, Oral , Adult , Androstenols/metabolism , Dehydroepiandrosterone/administration & dosage , Dehydroepiandrosterone/metabolism , Dehydroepiandrosterone/urine , Dihydrotestosterone/administration & dosage , Dihydrotestosterone/metabolism , Dihydrotestosterone/urine , Doping in Sports , Humans , Male , ROC Curve , Reference Values , Testosterone/administration & dosage , Testosterone/analogs & derivatives , Testosterone/metabolism , Testosterone/urine , Young Adult
16.
Drug Test Anal ; 2(11-12): 582-8, 2010.
Article in English | MEDLINE | ID: mdl-21204290

ABSTRACT

Doping with natural steroids can be detected by evaluating the urinary concentrations and ratios of several endogenous steroids. Since these biomarkers of steroid doping are known to present large inter-individual variations, monitoring of individual steroid profiles over time allows switching from population-based towards subject-based reference ranges for improved detection. In an Athlete Biological Passport (ABP), biomarkers data are collated throughout the athlete's sporting career and individual thresholds defined adaptively. For now, this approach has been validated on a limited number of markers of steroid doping, such as the testosterone (T) over epitestosterone (E) ratio to detect T misuse in athletes. Additional markers are required for other endogenous steroids like dihydrotestosterone (DHT) and dehydroepiandrosterone (DHEA). By combining comprehensive steroid profiles composed of 24 steroid concentrations with Bayesian inference techniques for longitudinal profiling, a selection was made for the detection of DHT and DHEA misuse. The biomarkers found were rated according to relative response, parameter stability, discriminative power, and maximal detection time. This analysis revealed DHT/E, DHT/5ß-androstane-3α,17ß-diol and 5α-androstane-3α,17ß-diol/5ß-androstane-3α,17ß-diol as best biomarkers for DHT administration and DHEA/E, 16α-hydroxydehydroepiandrosterone/E, 7ß-hydroxydehydroepiandrosterone/E and 5ß-androstane-3α,17ß-diol/5α-androstane-3α,17ß-diol for DHEA. The selected biomarkers were found suitable for individual referencing. A drastic overall increase in sensitivity was obtained. The use of multiple markers as formalized in an Athlete Steroidal Passport (ASP) can provide firm evidence of doping with endogenous steroids.


Subject(s)
Dehydroepiandrosterone/urine , Dihydrotestosterone/urine , Doping in Sports , Substance Abuse Detection/methods , Adult , Humans , ROC Curve , Sensitivity and Specificity , Steroids/urine , Young Adult
17.
Steroids ; 75(2): 154-63, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19962394

ABSTRACT

The detection of misuse with naturally occurring steroids is a great challenge for doping control laboratories. Intake of natural anabolic steroids alters the steroid profile. Thus, screening for exogenous use of these steroids can be established by monitoring a range of endogenous steroids, which constitute the steroid profile, and evaluate their concentrations and ratios against reference ranges. Elevated values of the steroid profile constitute an atypical finding after which a confirmatory IRMS procedure is needed to unequivocally establish the exogenous origin of a natural steroid. However, the large inter-individual differences in urinary steroid concentrations and the recent availability of a whole range of natural steroids (e.g. dehydroepiandrosterone and androstenedione) which each exert a different effect on the monitored parameters in doping control complicate the interpretation of the current steroid profile. The screening of an extended steroid profile can provide additional parameters to support the atypical findings and can give specific information upon the steroids which have been administered. The natural concentrations of 29 endogenous steroids and 11 ratios in a predominantly Caucasian population of athletes were determined. The upper reference values at 97.5%, 99% and 99.9% levels were assessed for male (n=2027) and female (n=1004) populations. Monitoring minor metabolites and evaluation of concentration ratios with respect to their natural abundances could improve the interpretation of the steroid profile in doping analysis.


Subject(s)
Athletes , Biomarkers/urine , Doping in Sports , Steroids/pharmacokinetics , Steroids/urine , Substance Abuse Detection/methods , Female , Gas Chromatography-Mass Spectrometry , Humans , Male , Reference Values
18.
Drug Test Anal ; 1(11-12): 531-7, 2009 Nov.
Article in English | MEDLINE | ID: mdl-20355169

ABSTRACT

Anabolic androgenic steroids are considered to be doping agents and are prohibited in sports. Their metabolism needs to be elucidated to allow for urinary detection by gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-tandem mass spectrometry (LC-MS/MS). Steroid metabolism was assessed using uPA(+/+) SCID mice with humanized livers (chimeric mice). This study presents the results of 19-norandrost-4-ene-3,17-dione (19-norAD) administration to these in vivo mice. As in humans, 19-norandrosterone and 19-noretiocholanolone are the major detectable metabolites of 19-norAD in the urine of chimeric mice.A summary is given of the metabolic pathways found in chimeric mice after administration of three model steroid compounds (methandienone, androst-4-ene-3,17-dione and 19-norandrost-4-ene-3,17-dione). From these studies we can conclude that all major metabolic pathways for anabolic steroids in humans are present in the chimeric mouse. It is hoped that, in future, this promising chimeric mouse model might assist the discovery of new and possible longer detectable metabolites of (designer) steroids.


Subject(s)
Androstenedione/pharmacokinetics , Estrenes/pharmacokinetics , Liver/metabolism , Methandrostenolone/pharmacokinetics , Steroids/pharmacokinetics , Transplantation Chimera/metabolism , Animals , Doping in Sports , Humans , Mice , Mice, SCID , Models, Animal , Molecular Structure , Placebos
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