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1.
Metabolites ; 14(3)2024 Feb 26.
Article in English | MEDLINE | ID: mdl-38535301

ABSTRACT

Adrenosterone (Androst-4-ene-3,11,17-trione, 11OXO) is forbidden in sports according to the Prohibited List of the World Anti-Doping Agency. The administration of 11OXO may be detected by monitoring the urinary concentrations of its main human metabolites 11ß-hydroxy-androsterone and 11ß-hydroxy-etiocholanolone. Preliminary urinary concentration and concentration ratio thresholds have been established for sports drug testing purposes, but adaptations are desirable as the suggested limits would result in numerous suspicious findings due to naturally elevated concentrations and ratios. Recently, the metabolism of 11-oxo-testosterone (KT) was investigated in the context of anti-doping research, resulting in a preliminary urinary concentration threshold and a confirmation procedure based on the determination of carbon isotope ratios (CIRs). Gas chromatography coupled to isotope ratio mass spectrometry was employed to investigate the CIRs of selected steroids. As KT is also a metabolite of 11OXO, the developed protocols for KT have been tested to elucidate their potential to detect the administration of 11OXO after a single oral dose of 100 mg. In order to further improve the analytical approach, the threshold for urinary concentrations of KT was re-investigated by employing a reference population of n = 5232 routine doping control samples. Quantification of urinary steroids was conducted by employing gas chromatography coupled to triple quadrupole mass spectrometry. Derived from these, a subset of n = 106 samples showing elevated concentrations of KT was investigated regarding their CIRs. By means of this, potentially positive samples due to the illicit administration of 11OXO or KT could be excluded, and the calculation of reference population-derived thresholds for the concentrations and CIR of KT was possible. Based on the results, the urinary concentration threshold for KT is suggested to be established at 130 ng/mL.

2.
Drug Test Anal ; 15(1): 27-41, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35633098

ABSTRACT

Consumption of hemp products is continuously growing, with an expanding scope of applications. Suppliers operate through different distribution channels, but the Internet is a major retail platform. Hemp products are prepared from cannabis plants and, therefore, might contain a variety of different natural cannabinoids. According to the regulations of the World Anti-Doping Agency, all natural and synthetic cannabinoids are prohibited in-competition, with the explicit exemption of cannabidiol. Therefore, an investigation of 23 hemp products for the presence of cannabinoids was performed to determine the likelihood of unintentional violations of anti-doping regulations. An assay for the detection of 16 cannabinoids in nutritional supplements was developed and validated. The sample preparation consisted of QuEChERS extraction, trimethylsilylation, and analysis by gas chromatography/tandem mass spectrometry. All 23 commercially available hemp products were analyzed, and assay characteristics such as selectivity, limit of detection, limit of identification, limit of quantification, linearity, imprecision, recovery, and accuracy were determined. Twenty of 23 hemp products included a variety of cannabinoids at, occasionally, substantial concentrations, with four products covering the entire spectrum of tested cannabinoids. An ethics committee-approved single-dose administration study was conducted with the commercially available hemp products, investigating the presence of 16 cannabinoids in urine collected pre- and post-consumption. Variable patterns of cannabinoids or their metabolites in urine were observed. In 30% of the urine samples collected 8 h after ingestion, the presence of a prohibited cannabinoid would have resulted in an unintentional violation of anti-doping regulations.


Subject(s)
Cannabidiol , Cannabinoids , Cannabis , Cannabis/chemistry , Gas Chromatography-Mass Spectrometry , Cannabinoids/analysis , Cannabidiol/analysis , Biological Assay
3.
Rapid Commun Mass Spectrom ; 36(17): e9343, 2022 Sep 15.
Article in English | MEDLINE | ID: mdl-35737649

ABSTRACT

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.


Subject(s)
Doping in Sports , Etiocholanolone , Androstenes , Etiocholanolone/urine , Mass Spectrometry/methods , Steroids/urine , Substance Abuse Detection/methods
4.
Drug Test Anal ; 13(11-12): 1835-1851, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34648228

ABSTRACT

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.


Subject(s)
Androsterone/analysis , Etiocholanolone/analysis , Testosterone Congeners/analysis , Testosterone/analysis , Androsterone/urine , Carbon Isotopes , Doping in Sports/prevention & control , Ethanol/administration & dosage , Ethanol/pharmacology , Etiocholanolone/urine , Female , Humans , Longitudinal Studies , Male , Mass Spectrometry/methods , Middle Aged , Substance Abuse Detection/methods , Testosterone/urine , Testosterone Congeners/urine
5.
Drug Test Anal ; 13(11-12): 1915-1920, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34378339

ABSTRACT

Little information on the human metabolism and urinary elimination of hydrafinil (9-fluorenol) exists. In order to support preventive anti-doping activities concerning compounds such as hydrafinil, a pilot elimination study was conducted with three healthy male volunteers receiving a single oral dose of 50 mg of hydrafinil. Urine samples were collected prior to and up to 72-h post-administration and were subjected to both gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry, which allowed for the identification of the intact drug as well as Phase I and Phase II metabolites, primarily hydroxylated and/or glucuronidated or sulfo-conjugated hydrafinil. The identity of these metabolites was corroborated by high-resolution/high-accuracy tandem mass spectrometry, and the applicability of routine doping control workflows for the detection of hydrafinil and its main metabolites was assessed. Therefore, two findings of hydrafinil and its metabolites were recorded, which concerned out-of-competition doping control samples and, hence, were not pursued with confirmatory analyses. Yet, the initial testing procedure results indicate that hydrafinil might require consideration in sports drug testing programs to ensure its detection, if classified as prohibited by the World Anti-Doping Agency (WADA).


Subject(s)
Doping in Sports/prevention & control , Mass Spectrometry/methods , Substance Abuse Detection/methods , Chromatography, Liquid/methods , Gas Chromatography-Mass Spectrometry/methods , Humans , Male
6.
Drug Test Anal ; 13(3): 539-549, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33125823

ABSTRACT

According to the World Anti-Doping Agency (WADA) regulations, cannabinoids use is prohibited in competition except for cannabidiol (CBD) use. For an adverse analytical finding (AAF) in doping control, cannabinoid misuse is based on identification of the pharmacologically inactive metabolite 11-nor-delta-9-carboxy-tetrahydrocannabinol-9-carboxylic acid (carboxy-THC) in urine at a concentration greater than 180 ng/ml. All other (minor) cannabinoids are reported as AAF when identified, except for CBD that has been explicitly excluded from the class of cannabinoids on WADA's Prohibited List since 2018. However, due to the fact that CBD isolated from cannabis plants may contain additional minor cannabinoids, the permissible use of CBD can lead to unintentional violations of antidoping regulations. An assay for the detection of 16 cannabinoids in human urine was established. The sample preparation consisted of enzymatic hydrolysis of glucuronide conjugates, liquid-liquid extraction, trimethylsilylation, and analysis by gas chromatography/tandem mass spectrometry (GC-MS/MS). Spot urine samples from CBD users, as well as specimens obtained from CBD administration studies conducted with 15 commercially available CBD products, were analyzed, and assay characteristics such as selectivity, reproducibility of detection at the minimum required performance level, limit of detection, and limit of identification were determined. An ethical committee approved controlled single dose commercially available CBD products administration study was conducted to identify 16 cannabinoids in urine samples collected after ingestion or application of the CBD products as well as their presence in spot urine samples of habitual CBD users. Variable patterns of cannabinoids or their metabolites were observed in the urine samples, especially when full spectrum CBD products were consumed. The presence of minor cannabinoids or their metabolites in an athlete's in-competition urine sample represents a substantial risk of an antidoping rule violation.


Subject(s)
Cannabidiol/analysis , Cannabinoids/analysis , Doping in Sports/prevention & control , Substance Abuse Detection/methods , Adult , Aged , Cannabidiol/urine , Cannabinoids/urine , Female , Gas Chromatography-Mass Spectrometry , Humans , Liquid-Liquid Extraction , Male , Middle Aged , Reproducibility of Results , Tandem Mass Spectrometry
7.
Drug Test Anal ; 12(11-12): 1581-1586, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33125835

ABSTRACT

The consumption of the offal of noncastrated pigs can lead to the excretion of 19-norandrosterone (NorA) in urine of humans. In doping control, GC/C/IRMS is the method of choice to differentiate between an endogenous or exogenous origin of urinary NorA. In some cases, after the consumption of wild boar offal, the δ13 C values of urinary NorA fulfill the criteria of an adverse analytical finding due to differing food sources of boar and consumer. However, consumption of wild boar's offal is not very common in Germany, and thus, the occurrence of such an analytical finding is unlikely. In contrast, the commerce with wild boar meat has increased in Germany within the last years. Up to 20,000 tons of wild boar meat are annually consumed. In order to probe for the probability of the occurrence of urinary NorA after consumption of wild boar meat, human urine samples were tested following the ingestion of commercially available game. In approximately half of the urine samples, traces of NorA were detected postadministration of 200 to 400 g boar meat. The highest urinary concentration was 2.9 ng/ml, and significant amounts were detected up to 9 h after the meal. δ13 C values ranged from -18.5‰ to -23.5‰, which would have led to at least two adverse analytical findings if the samples were collected in an antidoping context. IRMS analysis on German boar tissue samples showed that δ13 C values for wild boar's steroids are unpredictable and may vary seasonally.


Subject(s)
Doping in Sports/prevention & control , Estranes/urine , Meat/analysis , Substance Abuse Detection/methods , Animals , Doping in Sports/methods , Female , Gas Chromatography-Mass Spectrometry/methods , Gas Chromatography-Mass Spectrometry/standards , Germany , Humans , Male , Substance Abuse Detection/standards , Swine
8.
Rapid Commun Mass Spectrom ; 34(12): e8776, 2020 Jun 30.
Article in English | MEDLINE | ID: mdl-32143236

ABSTRACT

RATIONALE: The misuse of 7-oxo-DHEA (3ß-hydroxyandrost-5-ene-7,17-dione) is prohibited according to the World Anti-Doping Agency (WADA) code. Nevertheless, it is easily available as a dietary supplement and from black market sources. In two recent doping control samples, significant amounts of its main metabolite 7ß-OH-DHEA were identified, necessitating further investigations. METHODS: As both 7-oxo-DHEA and 7ß-OH-DHEA are endogenously produced steroids and no concentration thresholds applicable to routine doping controls exist, the development and validation of a carbon isotope ratio (CIR) mass spectrometry method ha been desirable. Excretion studies encompassing 7-oxo-DHEA, 7-oxo-DHEA-acetate, and in-house deuterated 7-oxo-DHEA were conducted and evaluated with regard to urinary CIR and potential new metabolites of 7-oxo-DHEA. RESULTS: Numerous urinary metabolites were identified, some of which have not been reported before, while others corroborate earlier findings on the metabolism of 7-oxo-DHEA. The CIRs of both 7-oxo-DHEA and 7ß-OH-DHEA were significantly influenced for more than 50 h after a single oral dose of 100 mg, and a novel metabolite (5α-androstane-3ß,7ß-diol-17-one) was found to prolong this detection time window by approximately 25 h. Applying the validated method to routine doping control specimens presenting atypically high urinary 7ß-OH-DHEA levels clearly demonstrated the exogenous origin of 7-oxo-DHEA and 7ß-OH-DHEA. CONCLUSIONS: As established for other endogenously produced steroids such as testosterone, the CIR allows for a clear differentiation between endo- and exogenous sources of 7-oxo-DHEA and 7ß-OH-DHEA. The novel metabolites detected after administration may help to improve the detection of 7-oxo-DHEA misuse and simplify its detection in doping control specimens.

9.
Drug Test Anal ; 11(11-12): 1644-1655, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31733090

ABSTRACT

The anabolic-androgenic steroid methylstenbolone (MSTEN; 2α,17α-dimethyl-17ß-hydroxy-5α-androst-1-en-3-one) is available as a so-called designer steroid or nutritional supplement. It is occasionally detected in doping control samples, predominantly tested and confirmed as the glucuronic acid conjugate of methylstenbolone. The absence of other meaningful metabolites reported as target analytes for sports drug testing purposes can be explained by the advertised metabolic stability of methylstenbolone. In 2013, a first investigation into the human metabolism of methylstenbolone was published, and two hydroxylated metabolites were identified as potential targets for initial testing procedures in doping controls. These metabolites were not observed in recent doping control samples that yielded adverse analytical findings for methylstenbolone, and in the light of additional data originating from a recent publication on the in vivo metabolism of methylstenbolone in the horse, revisiting the metabolic reactions in humans appeared warranted. Therefore, deuterated methylstenbolone together with hydrogen isotope ratio mass spectrometry (IRMS) in combination with high accuracy/high resolution mass spectrometry were employed. After oral administration of a single dose of 10 mg of doubly labeled methylstenbolone, urine samples were collected for 29 days. Up to 40 different deuterated methylstenbolone metabolites were detected in post-administration samples, predominantly as glucuronic acid conjugates, and all were investigated regarding their potential to prolong the detection window for doping controls. Besides methylstenbolone excreted glucuronidated, three additional metabolites were still detectable at the end of the study on day 29. The most promising candidates for inclusion into routine sports drug testing methods (2α,17α-dimethyl-5α-androst-1-ene-3ß,17ß-diol and 2α,17α-dimethyl-5α-androst-1-ene-3α,17ß-diol) were synthesized and characterized by NMR.


Subject(s)
Anabolic Agents/metabolism , Anabolic Agents/urine , Androstenols/metabolism , Androstenols/urine , Substance Abuse Detection/methods , Adult , Doping in Sports , Gas Chromatography-Mass Spectrometry/methods , Humans , Hydrogen Deuterium Exchange-Mass Spectrometry/methods , Male , Middle Aged
10.
Drug Test Anal ; 11(11-12): 1755-1760, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31670462

ABSTRACT

According to class M2.1 of the World Anti-Doping Agency (WADA) Prohibited List, the manipulation of doping control urine samples to alter their integrity and validity is prohibited both in- and out-of-competition. However, some paraplegic athletes with an overactive bladder need to be regularly treated with anti-cholinergic and anti-spasmodic drugs such as oxybutynin, which are often administered intravesically to reduce the substantial side effects observed after oral application. So far, it remains unclear whether such bladder instillations have a negative impact on analytical procedures and thus represent an anti-doping rule violation. Within this pilot study, urine samples were collected from five paraplegic athletes before and after an intravesical oxybutynin hydrochloride instillation. The samples were routinely tested for the presence of performance-enhancing drugs and afterwards fortified with 25 model compounds representing different classes of doping agents (anabolic agents, cannabinoids, diuretics, glucocorticoids, hormone and metabolic modulators, and stimulants) at low and medium concentrations. Additionally, the pH value and specific gravity were measured and the presence of oxybutynin was qualitatively determined by gas chromatography-mass spectrometry (GC-MS). In initial testing procedures, all samples were tested negative. Oxybutynin was present in most of the samples but found to have no significant effect on the detectability of the 25 model compounds subsequently added to each urine specimen. Therefore, it can be concluded that intravesical instillations with oxybutynin hydrochloride do not alter the integrity and validity of doping control urine samples.


Subject(s)
Mandelic Acids/urine , Performance-Enhancing Substances/urine , Substance Abuse Detection/methods , Urinalysis/methods , Urological Agents/urine , Administration, Intravesical , Doping in Sports , Female , Gas Chromatography-Mass Spectrometry/methods , Humans , Male , Mandelic Acids/administration & dosage , Pilot Projects , Urological Agents/administration & dosage
11.
Drug Test Anal ; 10(11-12): 1646-1656, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30379415

ABSTRACT

A steroidal compound was recently detected in a seized black market product and was identified as (17α,20E)-17,20-[(1-methoxyethylidene) bis (oxy)]-3-oxo-19-norpregna-4,20-diene-21-carboxylic acid methyl ester (YK11). This compound is described to possess selective androgen receptor modulator- and myostatin inhibitor-like properties. As YK11 is an experimental drug candidate and a non-approved substance for humans, scientific data on its metabolism is scarce. Due to its steroidal backbone and the arguably labile orthoester-derived moiety positioned at the D-ring, substantial metabolic conversion in vivo was anticipated. To unambiguously detect urinary metabolites of YK11, an elimination study with six-fold deuterated YK11 was conducted. Post-administration specimens were analyzed using hydrogen isotope ratio mass spectrometry coupled to single quadrupole mass spectrometry to identify metabolites alongside basic mass spectrometric data. Further characterization of those metabolites relevant to sports drug testing was accomplished using gas chromatography-high resolution-high accuracy mass spectrometry. Fourteen deuterated urinary metabolites were detected comprising unconjugated, glucuronidated, and sulfoconjugated metabolites. As expected, no intact YK11 was observed in the elimination study urine samples. While the unconjugated metabolites disappeared within 24 hours post-administration, both glucuronidated and sulfated metabolites were traceable for more than 48 hours. The chemical structures of the two most promising glucuronidated metabolites (5ß-19-nor-pregnane-3α,17ß,20-triol and 5ß-19-nor-pregnane-3α,17ß-diol-20-one) were verified by in-house synthesis of both metabolites and confirmed by nuclear magnetic resonance analysis. In order to elucidate their potential in sports drug testing, both were successfully implemented into the currently applied analytical method for the detection of anabolic agents.


Subject(s)
Androgens/metabolism , Androgens/urine , Norpregnadienes/metabolism , Norpregnadienes/urine , Androgens/administration & dosage , Androgens/chemistry , Doping in Sports , Gas Chromatography-Mass Spectrometry/methods , Humans , Magnetic Resonance Spectroscopy/methods , Male , Norpregnadienes/administration & dosage , Norpregnadienes/chemistry , Substance Abuse Detection/methods , Tandem Mass Spectrometry/methods
12.
Drug Test Anal ; 10(11-12): 1728-1733, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30230253

ABSTRACT

Isotope ratio mass spectrometry (IRMS) has been established in doping control analysis to identify the endogenous or exogenous origin of a variety of steroidal analytes including the 19-norsteroid metabolite norandrosterone (NorA). NorA can be found naturally in human urine in trace amounts due to endogenous demethylation or in situ microbial degradation. The administration of nortestosterone (nandrolone) or different prohormones results in the excretion of urinary NorA. Usually, this can be detected by IRMS due to differing δ13 C values of synthetic 19-norsteroids compared to endogenous reference compounds. The consumption of uncastrated pig edible parts like offal or even meat may also lead to a urinary excretion of NorA. In order to determine the δ13 C values of such a scenario, urine samples collected after consumption of a wild-boar-testicle meal were analyzed. IRMS revealed highly enriched δ13 C values for urinary NorA, which could be related to the completely corn-based nutrition of the animal. Isotopic analysis of the boar's bristles demonstrated a dietary change from C3 -based forage, probably in winter and spring, to a C4 -based diet in the last weeks to months prior to death. These results supported the interpretation of an atypical test result of a Central European athlete's doping control sample with δ13 C values for NorA of -18 ‰, most probably caused by the consumption of a wild boar ragout. As stated before, athletes should be fully aware of the risk that consumption of wild boar may result in atypical or even adverse analytical findings in sports drug testing.


Subject(s)
Estranes/analysis , Estranes/urine , Meat/analysis , Sus scrofa , Testis/chemistry , Animal Nutritional Physiological Phenomena , Animals , Carbon Isotopes/analysis , Carbon Isotopes/metabolism , Diet , Doping in Sports , Estranes/metabolism , Gas Chromatography-Mass Spectrometry/methods , Humans , Male , Nandrolone , Substance Abuse Detection/methods , Sus scrofa/physiology , Swine , Testis/metabolism
13.
Toxicol Lett ; 213(3): 381-91, 2012 Sep 18.
Article in English | MEDLINE | ID: mdl-22885098

ABSTRACT

The metabolism of a variety of anabolic steroids frequently misused for doping purposes has been investigated in the last years. This research mainly focused on main and long-term metabolites suitable for detection, but detailed clearance mechanisms have rarely been elucidated. Recent studies on metandienone focused on the identification of 17ß-hydroxymethyl-17α-methyl-18-norandrosta-1,4,13-trien-3-one (20ßOH-NorMD) as long-term metabolite, however, the metabolic pathway of its generation remained unclear. Metandienone and its Wagner-Meerwein rearrangement product 17,17-dimethyl-18-norandrosta-1,4,13-trien-3-one (NorMD) were hydroxylated by different human cytochrome P450 enzymes (CYPs). Some of their hydroxylation products were chemically synthesized and characterized by mass spectrometry to allow for their trace detection in urine samples. Following oral administration of metandienone or NorMD in one human volunteer each the post administration urines were checked for the presence of those hydroxylated metabolites using GC-MS/MS analysis. The human mitochondrial steroid hydroxylating enzymes CYP11B1 and CYP11B2 were capable to metabolize metandienone leading to the formation of 11ß-hydroxymetandienone and 18-hydroxymetandienone. Following Wagner-Meerwein rearrangement, the resulting products could be assigned to 20ßOH-NorMD and 11ßOH-NorMD. The contribution of CYP11B1 and CYP11B2 in human metabolism of metandienone was confirmed by analysis of post-administration samples of metandienone and NorMD. Combined with the results from a previous study, enzymatic pathways were identified that involve CYP21 and CYP3A4 in the hydroxylation of NorMD, while CYP21, CYP3A4 and CYP11B2 take part in 20ßOH-NorMD generation from MD. The current study represents a valuable contribution to the elucidation of clearance mechanisms of anabolic steroids and also indicates that mainly non-liver CYPs seem to be involved in these processes.


Subject(s)
Anabolic Agents/pharmacokinetics , Cytochrome P-450 CYP11B2/metabolism , Cytochrome P-450 CYP3A/metabolism , Methandrostenolone/pharmacokinetics , Performance-Enhancing Substances/pharmacokinetics , Steroid 21-Hydroxylase/metabolism , Administration, Oral , Anabolic Agents/administration & dosage , Anabolic Agents/urine , Biotransformation , Doping in Sports , Gas Chromatography-Mass Spectrometry , Humans , Hydroxylation , Male , Methandrostenolone/administration & dosage , Methandrostenolone/analogs & derivatives , Methandrostenolone/urine , Middle Aged , Performance-Enhancing Substances/administration & dosage , Performance-Enhancing Substances/urine , Recombinant Proteins/metabolism , Substance Abuse Detection/methods , Substrate Specificity , Tandem Mass Spectrometry
14.
Drug Test Anal ; 4(12): 942-50, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22354842

ABSTRACT

The aromatase inhibitor formestane (4-hydroxy-androst-4-ene-3,17-dione, F) is prohibited in sports by the World Anti-Doping Agency (WADA). F possesses only weak androgenic properties and is presumed to be employed in order to suppress estrogen production during the illicit intake of anabolic steroids by athletes. Former studies additionally showed that F is an endogenous steroid produced in low amounts. According to the regulations of WADA, urinary concentrations above 100 ng/ml are assumed to be due to ingestion of F. To distinguish between endogenous or exogenous sources of urinary F, isotope ratio mass spectrometry (IRMS) is the method of choice. Therefore, a method to determine the carbon isotope ratio (CIR) of F in urine samples was developed and validated. Routine samples (n = 42) showing concentrations of F above 5 ng/ml were investigated and enabled elucidation of the CIR of endogenous F and subsequent the calculation of a reference limit. A reference population encompassing n = 90 males and females was investigated regarding endogenous concentrations of F. An excretion study with one male volunteer was conducted to test and validate the developed method and to identify possible impact of F administration on other endogenous steroids. By CIR determination of F it is clearly possible to elucidate its endogenous or exogenous source. Taking into account the CIR of other target analytes like testosterone, a differentiation between F and androstenedione intake is possible. In 2011, the first exogenous F below the WADA threshold could be detected by means of the developed IRMS method.


Subject(s)
Androstenedione/analogs & derivatives , Aromatase Inhibitors/urine , Carbon Isotopes/urine , Doping in Sports , Gas Chromatography-Mass Spectrometry , Performance-Enhancing Substances/urine , Substance Abuse Detection/methods , Adult , Androstenedione/pharmacokinetics , Androstenedione/urine , Aromatase Inhibitors/pharmacokinetics , Biomarkers/urine , Calibration , Female , Gas Chromatography-Mass Spectrometry/standards , Humans , Limit of Detection , Male , Middle Aged , Performance-Enhancing Substances/pharmacokinetics , Predictive Value of Tests , Reference Values , Reproducibility of Results , Substance Abuse Detection/standards , Young Adult
15.
Drug Test Anal ; 3(11-12): 777-83, 2011.
Article in English | MEDLINE | ID: mdl-22095651

ABSTRACT

Zeranol ((7R,11S)-7,15,17-trihydroxy-11-methyl-12-oxabicyclo[12.4.0]octadeca-1(14),15,17-trien-13-one, also referred to as 7α-zearalanol, Ralone®, Frideron®, Ralgro®, etc.) is a semi-synthetic estrogenic veterinary drug with growth-promoting properties. Its use regarding animal husbandry has been prohibited in the European Union since 1981 and, due to its anabolic effects, it is further recognized as a banned substance in sport. Numerous studies were conducted concerning the identification of the illicit application of zeranol to domestic livestock. These studies also considered the natural occurrence of zeranol as a metabolite of the mycotoxin zearalenone and the issue of differentiating both scenarios, i.e. illegal use or unintended contamination. Human sports drug testing authorities are facing comparable challenges since the deliberate misuse of the (for human application non-approved) drug should be discriminated from adverse analytical findings resulting from the biotransformation of the mycotoxin zearalenone possibly ingested with contaminated food. The active drug (zeranol), its major human metabolites (zearalanone, 7ß-zearalanol) and the mycotoxin (zearalenone) plus its major and unique metabolic products (α-zearalenol, ß-zearalenol) have been monitored in routine doping controls by means of validated gas chromatography-(tandem) mass spectrometry (GC-(MS/)MS) methods since 1996, and between 2005 and 2010 four samples providing suspicious signals were detected. In agreement with literature data, in vitro metabolism studies demonstrated the metabolic pathway from zearalenone towards zeranol (and common metabolites). In contrast, an administration study urine sample (collected after oral application of 20 mg of zeranol) yielded only ultra-trace amounts of zearalenone and its characteristic metabolites, which supported the assumption that a mycotoxin contamination caused the finding of zeranol in the doping control specimens rather than a misuse of the anabolic agent.


Subject(s)
Estrogens, Non-Steroidal/metabolism , Gas Chromatography-Mass Spectrometry , Mycotoxins/metabolism , Substance Abuse Detection , Zearalenone/metabolism , Zeranol/metabolism , Animals , Doping in Sports , Estrogens, Non-Steroidal/urine , Female , Gas Chromatography-Mass Spectrometry/methods , Humans , Male , Mycotoxins/urine , Substance Abuse Detection/methods , Zearalenone/urine , Zeranol/analogs & derivatives , Zeranol/urine
16.
Endocrinology ; 152(12): 4718-28, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21990312

ABSTRACT

Various products containing rarely characterized anabolic steroids are nowadays marketed as dietary supplements. Herein, the designer steroid methyl-1-testosterone (M1T) (17ß-hydroxy-17α-methyl-5α-androst-1-en-3-one) was identified, and its biological activity, potential adverse effects, and metabolism were investigated. The affinity of M1T toward the androgen receptor (AR) was tested in vitro using a yeast AR transactivation assay. Its tissue-specific androgenic and anabolic potency and potential adverse effects were studied in a Hershberger assay (sc or oral), and tissue weights and selected molecular markers were investigated. Determination of M1T and its metabolites was performed by gas chromatography mass spectrometry. In the yeast AR transactivation assay, M1T was characterized as potent androgen. In rats, M1T dose-dependently stimulated prostate and levator ani muscle weight after sc administration. Oral administration had no effect but stimulated proliferation in the prostate and modulated IGF-I and AR expression in the gastrocnemius muscle in a dose-dependent manner. Analysis of tyrosine aminotransferase expression provided evidence for a strong activity of M1T in the liver (much higher after oral administration). In rat urine, 17α-methyl-5α-androstane-3α,17ß-diol, M1T, and a hydroxylated metabolite were identified. In humans, M1T was confirmed in urine in addition to its main metabolites 17α-methyl-5α-androst-1-ene-3α,17ß-diol and 17α-methyl-5α-androstane-3α,17ß-diol. Additionally, the corresponding 17-epimers as well as 17ß-hydroxymethyl-17α-methyl-18-nor-5α-androsta-1,13-dien-3-one and its 17-epimer were detected, and their elimination kinetics was monitored. It was demonstrated that M1T is a potent androgenic and anabolic steroid after oral and sc administration. Obviously, this substance shows no selective AR modulator characteristics and might exhibit liver toxicity, especially after oral administration.


Subject(s)
Endocrine System/drug effects , Methyltestosterone/metabolism , Methyltestosterone/pharmacology , Anabolic Agents , Androgens , Animals , Designer Drugs/administration & dosage , Designer Drugs/metabolism , Designer Drugs/pharmacology , Dietary Supplements , Humans , Methyltestosterone/administration & dosage , Organ Specificity , Rats , Steroids/administration & dosage , Steroids/metabolism , Steroids/pharmacology , Testosterone/analogs & derivatives
17.
Toxicol Lett ; 201(2): 101-4, 2011 Mar 05.
Article in English | MEDLINE | ID: mdl-21134425

ABSTRACT

Since a few years more and more products have appeared on the market for dietary supplements containing steroids that had never been marketed as approved drugs, mostly without proper labeling of the contents. Syntheses and few data on pharmacological effects are available dated back mainly to the 1950s or 1960s. Only little knowledge exists about effects and side effects of these steroids in humans. The present study reports the identification of Δ6-methyltestosterone in a product named "Jungle Warfare", which was obtained from a web-based supplement store. The main urinary metabolites, 17α-hydroxy-17ß-methylandrosta-4,6-dien-3-one (Δ6-epimethyl-testosterone), 17α-methyl-5ß-androstane-3α,17ß-diol (3α,5ß-THMT), and 17ß-methyl-5ß-androstane-3α,17α-diol, as well as the parent compound excreted after a single oral administration were monitored by GC-MS/MS. Δ6-Epimethyltestosterone and 3α,5ß-THMT served for long-term detection (still present in the 181-189 h urine). 17α-Methyltestosterone and its 17-epimer were not detected in the urines (LOD 0.3ng/mL). The highest concentrations were found in the 14-20.5h urine for Δ6-epimethyltestosterone (600 ng/mL), and 3α,5ß-THMT (240 ng/mL) and in the 36-44.5h urine for 17ß-methyl-5ß-androstane-3α,17α-diol (7 ng/mL). For reference methyltestosterone and epimethyltestosterone were dehydrogenated with chloranil. The characterization of the products was performed by GC-MS(/MS) and NMR.


Subject(s)
Dietary Supplements/analysis , Gas Chromatography-Mass Spectrometry/methods , Methyltestosterone/analysis , Tandem Mass Spectrometry/methods , Doping in Sports , Humans , Male , Methyltestosterone/metabolism , Middle Aged , Reference Standards
18.
Rapid Commun Mass Spectrom ; 24(15): 2245-54, 2010 Aug 15.
Article in English | MEDLINE | ID: mdl-20623476

ABSTRACT

Selective androgen receptor modulators (SARMs) are potent anabolic agents with tissue-selective properties. Due to their potential misuse in elite sport, the World Anti-Doping Agency (WADA) has prohibited SARMs since 2008, and although no representative drug candidate has yet received full clinical approval, recent findings of SARMs illegally sold via the internet have further supported the need to efficiently test for these compounds in doping controls. In the present communication, the mass spectrometric characterization of urinary metabolites of the SARM Andarine (also referred to as S-4) compared with earlier in vitro and animal studies is reported. Liquid chromatography interfaced to high-resolution/high-accuracy (tandem) mass spectrometry was used to identify phase I and II metabolites, confirming the predicted target analytes for sports drug testing purposes including the glucuronic acid conjugates of the active drug, its monohydroxylated and/or deacetylated product, the hydrolysis product resulting from the removal of the compound's B-ring, as well as the sulfate of the monohydroxylated and the deacetylated phase I metabolite. The obtained data will support future efforts to effectively screen for and confirm the misuse of the non-approved drug candidate Andarine.


Subject(s)
Acetamides/urine , Aminophenols/urine , Anabolic Agents/urine , Androgens , Doping in Sports , Mass Spectrometry/methods , Substance Abuse Detection/methods , Acetamides/metabolism , Aminophenols/metabolism , Anabolic Agents/metabolism , Doping in Sports/prevention & control , Humans , Male , Middle Aged
19.
Drug Test Anal ; 2(11-12): 637-42, 2010.
Article in English | MEDLINE | ID: mdl-21204295

ABSTRACT

The testosterone/epitestosterone (T/E) ratio was implemented as an indirect parameter for the detection of testosterone administration with an empirically established threshold value at T/E = 6. In 2005, the T/E reporting threshold was lowered from six to four. Between 2005 and 2009, 63 510 doping control urine samples were analyzed in the Cologne laboratory. A total of 1442 specimens (2.3%) showed a T/E > 4; 80 (5.5%) of which were tested positive by means of isotope ratio mass spectrometry (IRMS); and most of which (68) originated from strength sport disciplines. Specimens of high T/E ratio showed a much higher probability for being confirmed to contain exogenous testosterone using IRMS analysis than samples of low T/E values. Considering the small number of adverse analytical findings triggered by lowering the T/E reporting threshold (978 urine specimens with T/E ratios between 4 and 6 yielded only 4 (0.4%) positive IRMS findings) and the known limitations of the T/E ratio as discriminating parameter (UGT2B17 polymorphism), the currently mandatory approach shows only marginal overall efficiency. A more effective tool for the detection of the misuse of testosterone would be the implementation of individual reference ranges. Until athlete steroidal passports are available, it is suggested to exceed the threshold level for T/E from 4 to 6 and perform obligatory IRMS analysis for specimens showing T/E > 6. Further conditions triggering IRMS analysis could be suppressed luteinizing hormone (LH) values in males and disproportionate changes of relevant parameters in individual profiles evidently not resulting from ethanol consumption.


Subject(s)
Doping in Sports , Epitestosterone/urine , Substance Abuse Detection/trends , Testosterone/urine , Female , Humans , Male , Substance Abuse Detection/methods
20.
Rapid Commun Mass Spectrom ; 23(15): 2363-70, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19575395

ABSTRACT

New insights into the biochemistry of cardiac arrhythmia and skeletal muscle fatigue have yielded new drug candidates to counteract these phenomena. Major biological targets have become ryanodine receptor (RyR)-based Ca(2+)-release channels, which tend to 'leak' under various circumstances including strenuous exercise and, thus, cause aberrant calcium sparks that entail impaired muscle function. Therapeutics, which are referred to as rycals, are currently being developed to treat cardiac arrhythmia via enhancement of calstabin-ryanodine affinities that causes a stabilization of the RyR. These therapeutics possess potential for misuse in sports, and an early implementation of target analytes such as the benzothiazepine derivatives S-107 and JTV-519 or putative metabolites into doping control screening procedures is recommended. Reference compounds, deuterated analogues, and a putative metabolic product were synthesized, and electron ionization mass spectra of these products were studied and dissociation pathways elucidated by means of tandem mass spectrometry (MS/MS) and accurate mass measurements. The characterized analytes were incorporated into existing sports drug testing assays based on liquid-liquid extraction and subsequent gas chromatography/mass spectrometry (GC/MS) analysis, and specificity, lower limit of detection (4-6 ng/mL), intraday and interday precision (1.5-17.2%), as well as recovery (63-66%) were determined. The established procedure proved suitable for routine doping control analysis to detect a potential misuse of the drug candidate S-107 in elite sport.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Spectrometry, Mass, Electrospray Ionization/methods , Substance Abuse Detection/methods , Thiazepines/chemical synthesis , Thiazepines/urine , Female , Humans , Male , Molecular Structure , Sensitivity and Specificity , Thiazepines/metabolism
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