Formation of 19-norsteroids by in situ demethylation of endogenous steroids in stored urine samples

Simultaneous quantitation and identification of intact Nandrolone phase II oxo-metabolites based on derivatization and inject LC-MS/(HRMS) methodology

Α sensitive and selective derivatization and inject method for the quantification of intact nandrolone phase II oxo-metabolites was developed and validated using liquid chromatography - (tandem high resolution) mass spectrometry (LC-MS/(HRMS)). For the derivatization, Girard's reagent T (GRT) was used directly in natural urine samples and the analysis of the metabolites of interest was performed by direct injection into LC-MS/(HRMS) system operating in positive ionization mode. Derivatization enabled the efficient detection of nandrolone oxo-metabolites, while at the same time producing intense product ions under collision-induced dissociation (CID) conditions that are related to metabolites of the steroid backbone and not to the conjugated moieties. Glucuronide and sulfate metabolites of nandrolone were chromatographically resolved and quantified in the same run in the range of 1-100 ng mL-1, while at the same time structure identification could be performed for each metabolite. Full validation of the method was performed according to the World Anti-Doping Agency (WADA) International Standard for Laboratories (ISL). Nandrolone oxo-metabolites were quantified in two sets of urine samples, the first set consisted of real urine samples previously detected as negative and the second set consisted of urine samples collected from two excretion studies after nandrolone decanoate administration. The results for 19-norandrosterone glucuronide (19-NAG) and 19-noretiocholanolone glucuronide (19-NEG) were compared with those obtained by traditional gas chromatography - (tandem) mass spectrometry (GC-MS/[MS]) method.

δ13 C values of urinary 19-norandrosterone in antidoping samples and potential for adverse findings from boar offal consumption

19-Norandrosterone (19NA) is the preferred urinary target compound to identify doping with nandrolone or related 19-norsteroids. At concentrations between 2.5 and 15 ng/mL, isotope ratio mass spectrometry (IRMS) is required to establish exogenous origin of urinary 19NA. An absolute difference of 3‰ between urinary 19NA and an endogenous reference compound (ERC) constitutes a finding for exogenous origin of 19NA. Over the last 3 years, 77 samples containing urinary 19NA between 2.5 and 15 ng/mL were analyzed at our laboratory. The measured δ13 C values for 19NA ranged from -29.5‰ to -16.8‰. In comparison, the δ13 C values for the corresponding urinary ERCs ranged from -22.4‰ to -16.2‰. Due to the considerable overlap in values between the target compound and the natural range of urinary ERCs, it can be challenging to distinguish between endogenous and exogenous origins of urinary 19NA. In addition, it is well known that consumption of offal from non-castrated pigs can produce 19NA in urine. To determine whether this could cause a positive IRMS finding under the current IRMS positivity criteria, meat from non-castrated boars fed a mixture of corn and soy was consumed by 13 volunteers. Two volunteers produced 19NA findings above 2.5 ng/mL, and the measured isotope values, while inconsistent with documented 19-norsteroid preparations, did meet IRMS positivity criteria. However, these increases in 19NA urinary concentrations were short-lived due to rapid elimination. Timely follow-up collections may help support a claim for dietary exposure when low urinary concentrations of 19NA with pseudo-endogenous isotope values are observed.

Recent advances in identifying and utilizing metabolites of selected doping agents in human sports drug testing

Probing for evidence of the administration of prohibited therapeutics, drugs and/or drug candidates as well as the use of methods of doping in doping control samples is a central assignment of anti-doping laboratories. In order to accomplish the desired analytical sensitivity, retrospectivity, and comprehensiveness, a considerable portion of anti-doping research has been invested into studying metabolic biotransformation and elimination profiles of doping agents. As these doping agents include lower molecular mass drugs such as e.g. stimulants and anabolic androgenic steroids, some of which further necessitate the differentiation of their natural/endogenous or xenobiotic origin, but also higher molecular mass substances such as e.g. insulins, growth hormone, or siRNA/anti-sense oligonucleotides, a variety of different strategies towards the identification of employable and informative metabolites have been developed. In this review, approaches supporting the identification, characterization, and implementation of metabolites exemplified by means of selected doping agents into routine doping controls are presented, and challenges as well as solutions reported and published between 2010 and 2020 are discussed.

Detecting the abuse of 19-norsteroids in doping controls: A new gas chromatography coupled to isotope ratio mass spectrometry method for the analysis of 19-norandrosterone and 19-noretiocholanolone

The detection of 19-norsteroids abuse in doping controls currently relies on the determination of 19-norandrosterone (19-NA) by gas chromatography-tandem mass spectrometry (GC-MS/MS). An additional confirmatory analysis by gas chromatography coupled to isotope ratio mass spectrometry (GC-C-IRMS) is performed on samples showing 19-NA concentrations between 2.5 and 15 ng/ml and not originated from pregnant female athletes or female treated with 19-norethisterone. 19-Noretiocholanolone (19-NE) is typically produced to a lesser extent as a secondary metabolite. The aim of this work was to improve the GC-C-IRMS confirmation procedure for the detection of 19-norsteroids misuse. Both 19-NA and 19-NE were analyzed as target compounds (TCs), whereas androsterone (A), pregnanediol (PD), and pregnanetriol (PT) were selected as endogenous reference compounds (ERCs). The method was validated and applied to urine samples collected by three male volunteers after the administration of nandrolone-based formulations. Before the instrumental analysis, urine samples (<25 ml) were hydrolyzed with β-glucuronidase from Escherichia coli and extracted with n-pentane. Compounds of interest were purified through a single (for PT) or double (for 19-NE, 19-NA, A, and PD) liquid chromatographic step, to reduce the background noise and eliminate interferences that could have affect the accuracy of δ¹³ C values. The limit of quantification (LOQ) of 2 ng/ml was ensured for both 19-NA and 19-NE. The 19-NE determination could be helpful in case of "unstable" urine samples, in late excretion phases or when coadministration with 5α-reductase inhibitors occur.

Evaluation of nandrolone and ractopamine in the urine of veal calves: liquid chromatography-tandem mass spectrometry approach

Under European legislation, the use of growth promoters is forbidden in food-producing livestock. The application of unofficial protocols with diverse combinations of veterinary drugs, administered in very low concentrations, hinders reliable detection and subsequent operative prevention. It was observed that nandrolone (anabolic steroid) and ractopamine (β-adrenergic agonist) are occasionally administered to animals, but little is known about their synergic action when they are administered together. Two specific analytical methods based on liquid chromatography-tandem mass spectrometry have been developed, both of which include hydrolysis of the corresponding conjugates. For the nandrolone method, solid-phase extraction was necessary for the complete elimination of the interferences, while employment of the Quantitation Enhanced Data-Dependent scan mode during MS acquisition of ractopamine enabled the utilization of simple liquid-liquid extraction. The nandrolone method was linear in the range of 0.5-25 ng/mL, while the ractopamine calibration curve was constructed from 0.5 to 1000 ng/mL. The corresponding coefficients of correlations were >0.9907. The lower limit of quantification for both methods was 0.5 ng/mL, followed by overall recoveries >81%. Precisions expressed as relative standard deviations were <17%, while matrix effects were minimal. Urine samples taken at the slaughterhouse from veal calves enrolled in an experimental treatment consisting of intramuscular administration of β-nandrolone-phenylpropionate accompanied with a ractopamine-enriched diet were analysed. Those methods might be useful for studying the elimination patterns of the administered compounds along with characterization of the main metabolic pathways. Copyright © 2016 John Wiley & Sons, Ltd.

Atypical excretion profile and GC/C/IRMS findings may last for nine months after a single dose of nandrolone decanoate

The use of the anabolic androgenic steroid nandrolone and its prohormones is prohibited in sport. A common route of nandrolone administration is intramuscular injections of a nandrolone ester. Here we have investigated the detection time of nandrolone and 19-norandrosterone and 19-noretiocholanolone metabolites in eleven healthy men after the administration of a 150 mg dose of nandrolone decanoate. The urinary concentrations of nandrolone and the metabolites were monitored by GC-MS/MS for nine months and in some samples the presence of 19-norandrosterone was confirmed by GC/C/IRMS analysis. The participants were genotyped for polymorphisms in PDE7B1 and UGT2B15 genes previously shown to influence the activation and inactivation of nandrolone decanoate. There were large inter-individual variations in the excretion rate of nandrolone and the metabolites, although not related to genetic variations in the UGT2B15 (rs1902023) and PDE7B1 (rs7774640) genes. After the administration, 19-norandrosterone was found at 2-8-fold higher concentrations than 19-noretiocholanolone. We showed that nandrolone doping can be identified 4 and 9 months after the injection of only one single dose in six and three individuals, respectively. We also noted that GC/C/IRMS confirms the presence of exogenous 19-norandrosterone in the urine samples, showing δ13 values around -32 ‰. This was true even in a sample that was not identified as an atypical finding after the GC-MS/MS analysis further showing the power of using GC/C/IRMS in routine anti-doping settings.

Confounding factors and genetic polymorphism in the evaluation of individual steroid profiling

In the fight against doping, steroid profiling is a powerful tool to detect drug misuse with endogenous anabolic androgenic steroids. To establish sensitive and reliable models, the factors influencing profiling should be recognised. We performed an extensive literature review of the multiple factors that could influence the quantitative levels and ratios of endogenous steroids in urine matrix. For a comprehensive and scientific evaluation of the urinary steroid profile, it is necessary to define the target analytes as well as testosterone metabolism. The two main confounding factors, that is, endogenous and exogenous factors, are detailed to show the complex process of quantifying the steroid profile within WADA-accredited laboratories. Technical aspects are also discussed as they could have a significant impact on the steroid profile, and thus the steroid module of the athlete biological passport (ABP). The different factors impacting the major components of the steroid profile must be understood to ensure scientifically sound interpretation through the Bayesian model of the ABP. Not only should the statistical data be considered but also the experts in the field must be consulted for successful implementation of the steroidal module.

Carbon isotope ratios of nandrolone, boldenone, and testosterone preparations seized in Norway compared to those of endogenously produced steroids in a Nordic reference population

Determining the origin of anabolic androgenic steroids (AAS) that also are produced endogenously in the human body is a major issue in doping control. In some cases, the presence of nandrolone and boldenone metabolites might result from endogenous production. The GC-C-IRMS technique (gas chromatography-combustion-isotope ratio mass spectrometry) enables the carbon isotopic ratio (CIR) to be measured to determine the origin of these metabolites. The aim of this study was to use GC-C-IRMS to determine the δ(13) CVPDB values of seized boldenone and nandrolone preparations to decide if the steroids themselves were depleted in (13) C, compared to what is normally seen in endogenously produced steroids. In addition, several testosterone preparations were analyzed. A total of 69 seized preparations were analyzed. The nandrolone preparations showed δ(13) CVPDB values in the range of -31.5 ‰ to -26.7 ‰. The boldenone preparations showed δ(13) CVPDB values in the range of -32.0 ‰ to -27.8 ‰, and for comparison the testosterone preparations showed δ(13) CVPDB values of -31.0 ‰ to -24.2 ‰. The results showed that the values measured in the nandrolone and boldenone preparations were in the same range as those measured in the testosterone preparations. The study also included measurements of CIR of endogenously produced steroids in a Norwegian/Danish reference population. The δ(13) CVPDB values measured for the endogenous steroids in this population were in the range of -21.7 to -26.8. In general, most of the preparations investigated in this study show (13) C-depleted delta values compared to endogenously produced steroids reflecting a northern European diet.

Investigations of the microbial transformation of cortisol to prednisolone in urine samples

Doping control samples are normally collected under non-sterile conditions and sometimes, storage and transportation are influenced by parameters such as the temperature. Therefore, microbial contamination and subsequent alteration of a sample's composition are possible. Studies regarding sample collection in cattle breeding have already shown enzymatic transformation of endogenous testosterone to boldenone causing false-positive findings. The aim of the present study was to investigate whether positive doping cases with the synthetic corticosteroids prednisolone and prednisone may result from microbial transformation of the endogenous corticosteroids cortisol and cortisone, respectively. A method comprising parameters such as pH values and screening results for synthetic glucocorticosteroids as well as incubation experiments followed by liquid chromatographic and mass spectrometric analysis was employed to test for contaminating germs with Δ(1)-dehydrogenase activity. Over 700 urine samples comprising inpatient and doping control specimens were investigated. In none of them, 1,2-dehydrogenating activity was confirmed. These findings are in accordance with other studies. However, the problem of microbial alteration of doping control specimens with special respect to 1,2-dehydrogenation must not be underestimated. Article from a special issue on steroids and microorganisms.

Detection of the misuse of steroids in doping control

The list of prohibited substances of the World Anti-Doping Agency (WADA) classifies the administration of several steroids in sports as doping. Their analysis is generally performed using urine specimen as matrix. Lots of the steroids are extensively metabolised in the human body. Thus, knowledge of urinary excretion is extremely important for the sensitive detection of steroid misuse in doping control. The methods routinely used in steroid screening mainly focus on substances, that are excreted unconjugated or as glucuronides. Common procedures include deconjugation using a beta-glucuronidase enzyme. Following extraction and concentration the analytes are submitted to LC-MS(/MS) analysis and/or GC-MS(/MS) analyses. Besides the classical steroids, more and more products appear on the market for "dietary supplements" containing steroids that have never been marketed as approved drugs, mostly without proper labelling of the contents. To cover the whole range of potential products comprehensive screening tools have to be utilised in addition to the classical methods. Endogenous steroids, e.g. testosterone, represent a special group of compounds. As classical chemical methodology is incapable of discriminating synthetic hormones from the biosynthesised congeners, the method of steroid profiling is used for screening purpose. Additionally, based on isotope signatures a discrimination of synthetic and natural hormones can be achieved.

Presence and metabolism of endogenous androgenic-anabolic steroid hormones in meat-producing animals: a review

The presence and metabolism of endogenous steroid hormones in meat-producing animals has been the subject of much research over the past 40 years. While significant data are available, no comprehensive review has yet been performed. Species considered in this review are bovine, porcine, ovine, equine, caprine and cervine, while steroid hormones include the androgenic-anabolic steroids testosterone, nandrolone and boldenone, as well as their precursors and metabolites. Information on endogenous steroid hormone concentrations is primarily useful in two ways: (1) in relation to pathological versus 'normal' physiology and (2) in relation to the detection of the illegal abuse of these hormones in residue surveillance programmes. Since the major focus of this review is on the detection of steroids abuse in animal production, the information gathered to date is used to guide future research. A major deficiency in much of the existing published literature is the lack of standardization and formal validation of experimental approach. Key articles are cited that highlight the huge variation in reported steroid concentrations that can result when samples are analysed by different laboratories under different conditions. These deficiencies are in most cases so fundamental that it is difficult to make reliable comparisons between data sets and hence it is currently impossible to recommend definitive detection strategies. Standardization of the experimental approach would need to involve common experimental protocols and collaboratively validated analytical methods. In particular, standardization would need to cover everything from the demographic of the animal population studied, the method of sample collection and storage (especially the need to sample live versus slaughter sampling since the two methods of surveillance have very different requirements, particularly temporally), sample preparation technique (including mode of extraction, hydrolysis and derivatization), the end-point analytical detection technique, validation protocols, and the statistical methods applied to the resulting data. Although efforts are already underway (at HFL and LABERCA) to produce more definitive data and promote communication among the scientific community on this issue, the convening of a formal European Union working party is recommended.

Characterization of the oestrogenic activity of non-aromatic steroids: are there male-specific endogenous oestrogen receptor modulators?

BACKGROUND AND PURPOSE

The endogenous oestrogens have important biological functions in men as well as in women. Because 17beta-oestradiol and oestrone are also formed in the male body, these aromatic oestrogens are generally thought to be responsible for exerting the required oestrogenic functions in the male. In the present study, we tested the hypothesis that some of the non-aromatic steroids that are androgen precursors or metabolites with hydroxyl groups at C-3 and/or C-17 positions may also be able to serve as ligands for the oestrogen receptors (ER) in the male.

EXPERIMENTAL APPROACH

A total of sixty non-aromatic steroids (selected from families of androstens, androstans, androstadiens, oestrens and oestrans) were analysed for their ability to bind and activate the human ERalpha and ERbetain vitro and in cultured cells.

KEY RESULTS

Six of the non-aromatic steroids, that is, 5-androsten-3beta,17beta-diol, 5alpha-androstan-3beta,17beta-diol, 5(10)-oestren-3alpha,17beta-diol, 5(10)-oestren-3beta,17beta-diol, 4-oestren-3beta,17beta-diol and 5alpha-oestran-3beta,17beta-diol, were found to have physiologically relevant high binding affinity ( approximately 50% of that of oestrone) for human ERalpha and ERbeta. These non-aromatic steroids also activated the transcriptional activity of human ERs and elicited biological responses (such as growth stimulation) in two representative ER-positive human cancer cell lines (MCF-7 and LNCaP) with physiologically relevant potency and efficacy. Molecular docking analysis of these six active compounds showed that they could bind to ERalpha and ERbeta in a manner similar to that of 17beta-oestradiol.

CONCLUSIONS AND IMPLICATIONS

These results provide evidence for the possibility that some of the endogenous androgen precursors or metabolites could serve as male-specific ER ligands.

Nandrolone: a multi-faceted doping agent

Nandrolone or nortestosterone, an anabolic-androgenic steroid, has been prohibited by doping control regulations for more than 30 years. Although its main metabolism in the human body was already known at that time, and detection of its misuse by gas or liquid chromatographic separation with mass spectrometric detection is straightforward, many interesting aspects regarding this doping agent have appeared since.Over the years, nandrolone preparations have kept their position among the prohibited substances that are most frequently detected in WADA-accredited laboratories. Their forms of application range from injectable fatty acid esters to orally administered nandrolone prohormones. The long detection window for nandrolone ester preparations and the appearance of orally available nandrolone precursors have changed the pattern of misuse.At the same time, more refined analytical methods with lowered detection limits led to new insights into the pharmacology of nandrolone and revelation of its natural production in the body.Possible contamination of nutritional supplements with nandrolone precursors, interference of nandrolone metabolism by other drugs and rarely occurring critical changes during storage of urine samples have to be taken into consideration when interpreting an analytical finding.A set of strict identification criteria, including a threshold limit, is applied to judge correctly an analytical finding of nandrolone metabolites. The possible influence of interfering drugs, urine storage or natural production is taken into account by applying appropriate rules and regulations.

Two-step silylation procedure for the unified analysis of 190 doping control substances in human urine samples by GC–MS

Background: While a number of different derivatization procedures for screening GC–MS analysis of prohibited substances are followed by doping control laboratories, a unified derivatization procedure for the GC–MS analysis of 190 different doping agents was developed. Results: Following preliminary experiments, a two-step derivatization procedure was selected. The evaluation of various silylation parameters, such as reagent composition, reaction time, reaction temperature, catalysts and microwave oven reaction time, for this procedure was carried out. Conclusion: The suitability of the developed procedure was demonstrated through application on urine samples at concentration levels of the minimum required performance limit for all tested substances. This new derivatization procedure, which significantly decreases time and cost, is suitable for a routine basis application.

Excretion of norsteroids' phase II metabolites of different origin in human

The urinary phase II metabolites of norsteroids, 19-norandrosterone, 19-noretiocholanolone and 19-norepiandrosterone glucuronide and sulphate, were analyzed in samples collected during the pregnancy, following the administration of norsteroids or the consumption of edible parts of non-castrated pig and in athletes' samples in which they were found during routine controls. The level of the sulfo- and glucuroconjugated metabolites was precisely determined by GC/HRMS, after selective hydrolysis. The goal was to evaluate whether the fine analysis of the norsteroid conjugates produced and excreted in different conditions would show a pattern that could be linked to their origin. The delta (13)C values of the metabolites formed following the ingestion of edible parts of non-castrated pig were measured by isotope ratio mass spectrometry. Our results indicated that it is not possible to determine the origin of the urinary metabolites based upon the sole evaluation of the different metabolites and conjugates. The GC/C/IRMS is the only method permitting to distinguish between the exogenous and endogenous origin of the metabolites.

Profiling of 19-norandrosterone sulfate and glucuronide in human urine: implications in athlete's drug testing

19-Norandrosterone (19-NA) as its glucuronide derivative is the target metabolite in anti-doping testing to reveal an abuse of nandrolone or nandrolone prohormone. To provide further evidence of a doping with these steroids, the sulfoconjugate form of 19-norandrosterone in human urine might be monitored as well. In the present study, the profiling of sulfate and glucuronide derivatives of 19-norandrosterone together with 19-noretiocholanolone (19-NE) were assessed in the spot urines of 8 male subjects, collected after administration of 19-nor-4-androstenedione (100mg). An LC/MS/MS assay was employed for the direct quantification of sulfoconjugates, whereas a standard GC/MS method was applied for the assessment of glucuroconjugates in urine specimens. Although the 19-NA glucuronide derivative was always the most prominent at the excretion peak, inter-individual variability of the excretion patterns was observed for both conjugate forms of 19-NA and 19-NE. The ratio between the glucuro- and sulfoconjugate derivatives of 19-NA and 19-NE could not discriminate the endogenous versus the exogenous origin of the parent compound. However, after ingestion of 100mg 19-nor-4-androstenedione, it was observed in the urine specimens that the sulfate conjugates of 19-NA was detectable over a longer period of time with respect to the other metabolites. These findings indicate that more interest shall be given to this type of conjugation to deter a potential doping with norsteroids.

Doping in sport--1. Excretion of 19-norandrosterone by healthy women, including those using contraceptives containing norethisterone

19-Norandrosterone (19-NA) is the principal urinary metabolite of the anabolic steroid nandrolone and its prohormones. The administration of these 19-nor androgens is prohibited in sport by the World Anti-Doping Agency (WADA) but, even so, adverse findings for 19-NA continue to be commonly reported. Little is known about the urinary concentrations of 19-NA that can occur in women who are not using anabolic steroids, including those using oral contraceptives containing the 19-nor progestogen norethisterone. In 2004, WADA lowered the reporting threshold for 19-NA for females from 5 to 2ng/mL. The lack of any substantial data on 19-NA excretion in women prompted this large-scale investigation. In this investigation, single untimed urines collected from 1202 female volunteers, 38 of whom were taking norethisterone containing contraceptives, were analysed for 19-NA. None of the women was a competitive athlete and pregnancy had been excluded by a urinary test for human chorionic gonadotropin (hCG). Only one sample exceeded the 19-NA reporting threshold having a concentration of 4.1ng/mL. This sample was from a user of a norethisterone-containing contraceptive.

Nandrolone excretion in sedentary vs physically trained young women

We investigated the effects of the menstrual cycle, oral contraception and physical training on exhaustive exercise-induced changes in the excretion of nandrolone metabolites [19-norandrosterone (19-NA), and 19-noretiocholanolone (19-NE)] in young women. Twenty-eight women were allocated to an untrained group (n=16) or a trained group (n=12), depending on their physical training background. The untrained group was composed of nine oral contraceptive users (OC+) and seven eumenorrheic women (OC-), while the trained group was entirely composed of OC+ subjects. Three laboratory sessions were conducted in a randomized order: a prolonged exercise test, a short-term exercise test and a control session. Urine specimens were collected before and 30, 60 and 90 min after the exercise test and at the same times of the day during the control session. Urinary concentrations of nandrolone metabolites were determined by gas chromatography coupled to mass spectrometry. Urinary concentrations of 19-NA and 19-NE ranged from undetectable levels to 1.14 and 0.47 ng/mL, respectively. Nandrolone excretion was not affected by the menstrual cycle phase (early follicular vs mid-luteal), prior physical training, oral contraception or acute physical exercise. Therefore, a urinary concentration of 2 ng/mL of 19-NA appears to be fair as the upper acceptable limit in doping control tests for female athletes.

Quantitative analysis of DHEA and androsterone in female urine: investigating the effects of menstrual cycle, oral contraception and training on exercise-induced changes in young women

Dehydroepiandrosterone (DHEA) and its metabolite androsterone (A) are natural steroids secreted in high quantities in human body. To assess the influence of oral contraceptives, menstrual cycle phase, and also physical exercise (acute and chronic such as training) on these metabolites excretions, a collection of 28 female urine specimens was organized. A three-extraction-step method was developed, and the analyses were performed by gas chromatography-mass spectrometry using deuterated 19-noretiocholanolone as the internal standard. Sample hydration state was found to be of great importance for kinetic studies, as it directly influenced the concentrations. No influence of menstrual cycle and training was found for androsterone and DHEA. However, oral contraceptive intake lowered DHEA excretion in urine and A seems to be slightly affected by exercise.

Urinary metabolic profile of 19-norsteroids in humans: glucuronide and sulphate conjugates after oral administration of 19-nor-4-androstenediol

19-Nor-4-androstenediol (NOL) is a prohormone of nandrolone (ND). Both substances are included in the WADA List of Prohibited Classes of Substances and their administration is determined by the presence of 19-norandrosterone (NA) with the urinary threshold concentration of 2 ng mL(-1). Routine analytical procedures allow the determination of NA excreted free and conjugated with glucuronic acid, but amounts of ND and NOL metabolites are also excreted in the sulphate fraction. The aim of this study is to determine the urinary metabolic profile after oral administration of a nutritional supplement containing NOL. Urine samples were collected up to 96 h following supplement administration and were extracted to obtain separately three metabolic fractions: free, glucuronide and sulphate. Extraction with tert-butyl methyl ether was performed after the hydrolysis steps and trimethylsilyl derivatives were analyzed by gas chromatography/mass spectrometry (GC/MS). After oral administration of NOL, the main metabolites detected were NA and noretiocholanolone (NE) in the glucuronide and sulphate fractions. The relative abundances of each metabolite in each fraction fluctuate with time; a few hours after administration the main metabolite was NA glucuronide whereas in the last sample (4 days after administration) the main metabolite was the NA sulphate and the second was the NE glucuronide. During the studied period almost half of the dose was excreted and the main metabolites were still found in urine after 96 h. Norepiandrosterone and norepietiocholanolone were also detected only in the sulphate fraction. Our results suggest that sulphate metabolites should be taken into consideration in order to increase the retrospectivity in the detection of 19-norsteroids after oral administration.

Factors influencing the steroid profile in doping control analysis

Steroid profiling is one of the most versatile and informative screening tools for the detection of steroid abuse in sports drug testing. Concentrations and ratios of various endogenously produced steroidal hormones, their precursors and metabolites including testosterone (T), epitestosterone (E), dihydrotestosterone (DHT), androsterone (And), etiocholanolone (Etio), dehydroepiandrosterone (DHEA), 5alpha-androstane-3alpha,17beta-diol (Adiol), and 5beta-androstane-3alpha,17beta-diol (Bdiol) as well as androstenedione, 6alpha-OH-androstenedione, 5beta-androstane-3alpha,17alpha-diol (17-epi-Bdiol), 5alpha-androstane-3alpha,17alpha-diol (17-epi-Adiol), 3alpha,5-cyclo-5alpha-androstan-6beta-ol-17-one (3alpha,5-cyclo), 5alpha-androstanedione (Adion), and 5beta-androstanedione (Bdion) add up to a steroid profile that is highly sensitive to applications of endogenous as well as synthetic anabolic steroids, masking agents, and bacterial activity. Hence, the knowledge of factors that do influence the steroid profile pattern is a central aspect, and pharmaceutical (application of endogenous steroids and various pharmaceutical preparations), technical (hydrolysis, derivatization, matrix), and biological (bacterial activities, enzyme side activities) issues are reviewed.

History of mass spectrometry at the Olympic Games

Mass spectrometry has played a decisive role in doping analysis and doping control in human sport for almost 40 years. The standard of qualitative and quantitative determinations in body fluids has always attracted maximum attention from scientists. With its unique sensitivity and selectivity properties, mass spectrometry provides state-of-the-art technology in analytical chemistry. Both anti-doping organizations and the athletes concerned expect the utmost endeavours to prevent false-positive and false-negative results of the analytical evidence. The Olympic Games play an important role in international sport today and are milestones for technical development in doping analysis. This review of the part played by mass spectrometry in doping control from Munich 1972 to Beijing 2008 Olympics gives an overview of how doping analysis has developed and where we are today. In recognizing the achievements made towards effective doping control, it is of the utmost importance to applaud the joint endeavours of the World Anti-Doping Agency, the International Olympic Committee, the international federations and national anti-doping agencies to combat doping. Advances against the misuse of prohibited substances and methods, which are performance-enhancing, dangerous to health and violate the spirit of sport, can be achieved only if all the stakeholders work together.

Significance of 19-norandrosterone in athletes' urine samples

Nandrolone and other 19-norsteroid potent anabolic steroids have been prohibited in sports for 30 years. The detection of the main urinary metabolite--19-norandrosterone--in amounts greater than 2 ng/ml constitutes an adverse analytical finding. The presence in nutritional sport supplements of steroids not listed on the label has undoubtedly resulted in positive tests, but inadvertent consumption of meat containing residues of hormonal treatment should not realistically cause apprehension. Although highly improbable, athletes should prudently avoid meals composed of pig offal in the hours preceding the test since the consumption of edible parts of a non-castrated pig, containing 19-nortestosterone, has been shown to results in the excretion of 19-norandrosterone in the following hours. Norsteroid metabolites are formed during pregnancy and excreted as minor metabolites of norethisterone, and minute amounts have been identified in some male and female samples when using more sensitive techniques of detection. Whereas exercise does not seem to be a significant factor in 19-norandrosterone excretion, some rare urine samples were found to be a suitable medium for in situ 19-demethylation of urinary metabolites.

Metabolism and excretion of anabolic steroids in doping control--new steroids and new insights

The use of anabolic steroids in sports is prohibited by the World Anti-Doping Agency. Until the 1990s, anabolic steroids were solely manufactured by pharmaceutical companies, albeit sometimes on demand from national sports agencies as part of their doping program. Recently the list of prohibited anabolic steroids in sports has grown due to the addition of numerous steroids that have been introduced on the market by non-pharmaceutical companies. Moreover, several designer steroids, specifically developed to circumvent doping control, have also been detected. Because anabolic steroids are most often intensively subjected to phase I metabolism and seldom excreted unchanged, excretion studies need to be performed in order to detect their misuse. This review attempts to summarise the results of excretion studies of recent additions to the list of prohibited steroids in sports. Additionally an update and insight on new aspects for "older" steroids with respect to doping control is given.

Detection and quantification of glucuro- and sulfoconjugated metabolites in human urine following oral administration of xenobiotic 19-norsteroids

Recently, the endogenous origin of nandrolone (19-nortestosterone) and other 19-norsteroids has been a focus of research in the field of drug testing in sport. In the present study, we investigated metabolites conjugated to a glucuronic acid and to a sulfuric acid in urine following administration of four xenobiotic 19-norsteroids. Adult male volunteers administered a single oral dose (10 mg) of each of four 19-norsteroids. Urinary samples collected from 0 to 120 h were subjected to methanolysis and beta-glucuronidase hydrolysis and were derivatized by N-methyl-N-trimethylsilyltrifluoroacetamide (MSTFA) before gas chromatography-mass spectrometry analysis. We confirmed that 19-norandrosterone (19-NA) and 19-noretiocholanolone (19-NE) were present in both glucuronide (g) and sulfate (s) conjugates and 19-norepiandrosterone (19-NEA) was excreted exclusively as a sulfate fraction in urine of all 19-norsteroids tested. The overall levels of the three metabolites can be ranked as follows: 19-NA(g+s)>19-NE(g+s)>19-NEA(s). The concentration profiles of these three metabolites in urine peaked between 2 to 12h post-administration and declined thereafter until approximately 72-96 h. 19-NA was most prominent throughout the first 24 h post-administration, except for a case in which an inverse relationship was found after 6h post-administration of nandrolone. Furthermore, we found that sulfate conjugates were present in both 19-NA and 19-NE metabolites in urine of all 19-norsteroids tested. The averaged total amounts of metabolites (i.e. 19-NA(s+g)+19-NE(s+g)+19-NEA(s)) excreted in urine were 38.6, 42.9, 48.3 and 21.6% for nandrolone, 19-nor-4-androsten-3,17-dione, 19-nor-4-androsten-3beta,17beta-diol and 19-nor-5-androstene-3beta,17beta-diol, respectively. Results from the excretion studies demonstrate significance of sulfate-conjugated metabolites on interpretation of misuse of the 19-norsteroids.

Quantitative determination of metabolic products of 19-norandrostenediol in human plasma using gas chromatography/mass spectrometry

Prohormones such as 19-norandrostenediol (estr-4-ene-3beta,17beta-diol) have been added to the list of prohibited substances of the World Anti-Doping Agency because they are metabolized to the common nandrolone metabolites norandrosterone and noretiocholanolone. So far, no studies on the metabolism and in vivo conversion of 19-norandrostenediol after oral or sublingual administration have been reported nor have had quantified data on resulting plasma nandrolone levels. In the present study, an open-label crossover trial with eight healthy male volunteers was conducted. After application of capsules or sublingual tablets of 19-norandrostenediol plasma concentrations of 19-norandrostenediol, nandrolone as well as major metabolites (19-norandrosterone and 19-noretiocholanolone) were determined using a validated assay based on gas chromatography/mass spectrometry. The administration of 100-mg capsules of 19-norandrostenediol yielded maximum plasma total concentrations (i.e., conjugated plus unconjugated compounds) of 1.1 ng/ml (+/-0.7) for 19-norandrostenediol, 4.0 ng/ml (+/-2.6) for nandrolone, 154.8 ng/ml (+/-130.8) for 19-norandrosterone, and 37.7 ng/ml (+/-6.9) for 19-noretiocholanolone. The use of 25-mg sublingual tablets resulted in 3.3 ng/ml (+/-1.0) for 19-norandrostenediol, 11.0 ng/ml (+/-6.4) for nandrolone, 106.3 ng/ml (+/-40.1) for 19-norandrosterone, and 28.5 ng/ml (+/-20.8) for 19-noretiocholanolone. Most interestingly, the pharmacologically active unconjugated nandrolone was determined after administration of sublingual tablets (up to 5.7 ng/ml) in contrast to capsule applications. These results demonstrate the importance of prohibiting prohormones such as 19-norandrostenediol, in particular, since plasma concentrations of nandrolone between 0.3 to 1.2 ng/ml have been reported to influence endocrinological parameters.

Determination of urinary norandrosterone excretion in females during one menstrual cycle by gas chromatography/mass spectrometry

Conjugated norandrosterone is the main urinary metabolite of anabolic steroids like nandrolone, norandrostenedione and norandrostenediol. Nandrolone traces of endogenous origin have been identified in human follicular fluid, and further investigations revealed urinary excretion of norandrosterone in pregnant and non-pregnant females and even males. A threshold level for the norandrosterone concentration in urine has been established when controlling the administration of prohibited nandrolone or its precursors in human doping control. This level has been set to 2 ng/mL for males and females. To investigate the excretion of conjugated norandrosterone in females more systematically, we collected daily urine samples from 12 female volunteers during a whole menstrual cycle. These samples were analysed for norandrosterone down to a limit of quantification and identification of 0.05 ng/mL (180 pmol/L). The results clearly show that all the volunteers excreted norandrosterone glucuronide in a characteristic pattern during one menstrual cycle. Concentrations in urine were considerably lower at the beginning of the follicular and the end of the luteal phases than midcyclic. Peak concentrations up to 0.8 ng/mL (2.9 nmol/L) were recorded and they were three to four times higher than the values at the beginning and end of the cycle. The time of the peak concentration was clearly related to the increased excretion of luteinizing hormone. These results strongly support the possibility of endogenous nandrolone production as a side reaction to enzymatic aromatisation. However, a threshold value of 2 ng/mL for reporting adversed findings in doping control of females was never reached in any of the samples.

Steroids: partial synthesis in medicinal chemistry

This article reviews the progress in the chemistry of the steroids that was published between January and December 2005. The reactions and partial synthesis of estrogens, androgens, pregnanes, bile acid derivatives, cholestanes and vitamin D analogues are covered. There are 139 references.

Determination of the origin of urinary norandrosterone traces by gas chromatography combustion isotope ratio mass spectrometry

On the one hand, 19-norandrosterone (NA) is the most abundant metabolite of the synthetic anabolic steroid 19-nortestosterone and related prohormones. On the other hand, small amounts are biosynthesized by pregnant women and further evidence exists for physiological origin of this compound. The World Anti-Doping Agency (WADA) formerly introduced threshold concentrations of 2 or 5 ng of NA per ml of urine to discriminate 19-nortestosterone abuse from biosynthetic origin. Recent findings showed however, that formation of NA resulting in concentrations in the range of the threshold levels might be due to demethylation of androsterone in urine, and the WADA 2006 Prohibited List has defined NA as endogenous steroid. To elucidate the endogenous or exogenous origin of NA, (13)C/(12)C-analysis is the method of choice since synthetic 19-nortestosterone is derived from C(3)-plants by partial synthesis and shows delta(13)C(VPDB)-values of around -28 per thousand. Endogenous steroids are less depleted in (13)C due to a dietary mixture of C(3)- and C(4)-plants. An extensive cleanup based on two high performance liquid chromatography cleanup steps was applied to quality control and doping control samples, which contained NA in concentrations down to 2 ng per ml of urine. (13)C/(12)C-ratios of NA, androsterone and etiocholanolone were measured by gas chromatography/combustion/isotope ratio mass spectrometry. By comparing delta(13)C(VPDB)-values of androsterone as endogenous reference compound with NA, the origin of NA in doping control samples was determined as either endogenous or exogenous.