Studies on anabolic steroids--12. Epimerization and degradation of anabolic 17 beta-sulfate-17 alpha-methyl steroids in human: qualitative and quantitative GC/MS analysis

The in vivo metabolism of Jungle Warfare in greyhounds

Δ6-Methyltestosterone was reported as the main active ingredient of the purported "dietary supplement" Jungle Warfare. This compound is structurally similar to 17α-methyltestosterone, containing an additional Δ6 double bond, and is reported to possess notable androgenic activity, raising concerns over the potential for abuse of Jungle Warfare in sport. The in vivo metabolism of Δ6-methyltestosterone in greyhounds was investigated. Urinary phase I (unconjugated) and phase II (glucuronide) metabolites were detected following oral administration using liquid chromatography-mass spectrometry. No phase II sulfate metabolites were detected. The major phase I metabolite was confirmed as 16α,17β-dihydroxy-17α-methylandrosta-4,6-dien-3-one by comparison with a synthetically-derived reference material. Minor amounts of the parent drug were also confirmed. Glucuronide conjugated metabolites were also observed, but were found to be resistant to hydrolysis using the Escherichia coli β-glucuronidase enzyme. Qualitative excretion profiles, limits of detection, and extraction recoveries were determined for the parent drug and the major phase I metabolite. These results provide a method for the detection of Jungle Warfare abuse in greyhounds suitable for incorporation into routine screening methods conducted by anti-doping laboratories.

Synthesis of stable isotope labelled steroid bis(sulfate) conjugates and their behaviour in collision induced dissociation experiments

Steroid bis(sulfate) metabolites derived from the two-fold sulfation of unconjugated precursors represent an important yet understudied portion of the steroid profile. The investigation of these compounds in fields such as medicine or anti-doping science relies on mass spectrometry (MS) as the principal tool to identify and quantify biomarkers of interest and depends in turn on access to steroid reference materials and their stable isotope labelled (SIL) derivatives. A new [¹⁸O] stable isotope label for sulfate metabolites is reported, which allows for the selective, late-stage and 'one-pot' synthesis of a variety of SIL-steroid conjugates suitable as MS probes and internal standards. The method is applied to more comprehensively study the MS behaviour of steroid bis(sulfate) compounds through collision-induced dissociation (CID) experiments.

Medaka embryos as a model for metabolism of anabolic steroids

In anti-doping science, the knowledge of drug metabolism is a prerequisite to identify analytical targets for the detection of misused prohibited substances. As the most obvious way to study xenobiotic metabolism, the administration to human volunteers, faces ethical concerns, there is a need for model systems. In the present study, we investigated whether Oryzias latipes (medaka) embryos might be an alternative, non-animal test model to study human-like metabolism. In the present study, we exposed medaka embryos at the morula stage to the anabolic steroid metandienone (10 µM or 50 µM) for a period of 2 or 8 days. According to the fish embryo toxicity test (OECD test), we assessed the developmental status of the embryos. We further investigated metandienone metabolites by high-performance liquid chromatography- and gas chromatography-mass spectrometry. Medaka embryos produced three mono-hydroxylated and one reduced metabolite known from human biotransformation. Developmental malformations were observed for the exposition to 50 µM metandienone, while a significant elevation of the heart beat was also present in those individuals exposed to the lower dose for 8 days. The present study demonstrates that the medaka embryo represents a promising model to study human-like metabolism. Moreover, the judgement of developmental parameters of the fish embryos enables for the simultaneous assessment of toxicity.

MASS SPECTROMETRIC FRAGMENTATION OF TRIMETHYLSILYL AND RELATED ALKYLSILYL DERIVATIVES

This review describes the mass spectral fragmentation of trimethylsilyl (TMS) and related alkylsilyl derivatives used for preparing samples for analysis, mainly by combined gas chromatography and mass spectrometry (GC/MS). The review is divided into three sections. The first section is concerned with the TMS derivatives themselves and describes fragmentation of derivatized alcohols, thiols, amines, ketones, carboxylic acids and bifunctional compounds such as hydroxy- and amino-acids, halo acids and hydroxy ethers. More complex compounds such as glycerides, sphingolipids, carbohydrates, organic phosphates, phosphonates, steroids, vitamin D, cannabinoids, and prostaglandins are discussed next. The second section describes intermolecular reactions of siliconium ions such as the TMS cation and the third section discusses other alkylsilyl derivatives. Among these latter compounds are di- and trialkyl-silyl derivatives, various substituted-alkyldimethylsilyl derivatives such as the tert-butyldimethylsilyl ethers, cyclic silyl derivatives, alkoxysilyl derivatives, and 3-pyridylmethyldimethylsilyl esters used for double bond location in fatty acid spectra. © 2019 Wiley Periodicals, Inc. Mass Spec Rev 0000:1-107, 2019.

Replacing PAPS: In vitro phase II sulfation of steroids with the liver S9 fraction employing ATP and sodium sulfate

In vitro technologies provide the capacity to study drug metabolism where in vivo studies are precluded due to ethical or financial constraints. The metabolites generated by in vitro studies can assist anti-doping laboratories to develop protocols for the detection of novel substances that would otherwise evade routine screening efforts. In addition, professional bodies such as the Association of Official Racing Chemists (AORC) currently permit the use of in-vitro-derived reference materials for confirmation purposes providing additional impetus for the development of cost effective in vitro metabolism platforms. In this work, alternative conditions for in vitro phase II sulfation using human, equine or canine liver S9 fraction were developed, with adenosine triphosphate (ATP) and sodium sulfate in place of the expensive and unstable co-factor 3'-phosphoadenosine-5'-phosphosulfate (PAPS), and employed for the generation of six representative steroidal sulfates. Using these conditions, the equine in vitro phase II metabolism of the synthetic or so-called designer steroid furazadrol ([1',2']isoxazolo[4',5':2,3]-5α-androstan-17β-ol) was investigated, with ATP and Na₂ SO₄ providing comparable metabolism to reactions using PAPS. The major in vitro metabolites of furazadrol matched those observed in a previously reported equine in vivo study. Finally, the equine in vitro phase II metabolism of the synthetic steroid superdrol (methasterone, 17β-hydroxy-2α,17α-dimethyl-5α-androstan-3-one) was performed as a prediction of the in vivo metabolic profile.

Constant Ion Loss Method for the Untargeted Detection of Bis-sulfate Metabolites

The untargeted detection of phase II metabolites is a key issue for the study of drug metabolism in biological systems. Sensitive and selective mass spectrometric (MS) techniques coupled to ultrahigh performance liquid chromatographic (UHPLC) systems are the most effective for this purpose. In this study, we evaluate different MS approaches with a triple quadrupole instrument for the untargeted detection of bis-sulfate metabolites. Bis-sulfates of 23 steroid metabolites were synthesized and their MS behavior was comprehensively studied. Bis-sulfates ionized preferentially as the dianion ([M - 2H]^2-) with a small contribution of the monoanion ([M - H]^-). Product ion spectra generated from the [M - 2H]^2- precursor ions were dominated by the loss of HSO₄^- to generate two product ions, that is, the ion at m/z 97 (HSO₄^-) and the ion corresponding to the remaining monosulfate fragment. Other product ions were found to be specific for some structures. As an example, the loss of [CH₃ + SO₃]^- was found to be important for several compounds with unsaturation adjacent to the sulfate. On the basis of the common behavior of the bis-sulfate metabolites two alternatives were evaluated for the untargeted detection of bis-sulfate metabolites (i) a precursor ion scan method using the ion at m/z 97 and (ii) a constant ion loss (CIL) method using the loss of HSO₄^-. Both methods allowed for the untargeted detection of the model compounds. Eight steroid bis-sulfates were synthesized in high purity in order to quantitatively evaluate the developed strategies. Lower limits of detection (2-20 ng/mL) were obtained using the CIL method. Additionally, the CIL method was found to be more specific in the detection of urinary bis-sulfates. The applicability of the CIL approach was demonstrated by determining progestogens altered during pregnancy and by detecting the bis-sulfate metabolites of tibolone.

Sulfate metabolites as alternative markers for the detection of 4-chlorometandienone misuse in doping control

Sulfate metabolites have been described as long-term metabolites for some anabolic androgenic steroids (AAS). 4-chlorometandienone (4Cl-MTD) is one of the most frequently detected AAS in sports drug testing and it is commonly detected by monitoring metabolites excreted free or conjugated with glucuronic acid. Sulfation reactions of 4Cl-MTD have not been studied. The aim of this work was to evaluate the sulfate fraction of 4Cl-MTD metabolism by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to establish potential long-term metabolites valuable for doping control purposes. 4Cl-MTD was administered to two healthy male volunteers and urine samples were collected up to 8 days after administration. A theoretical selected reaction monitoring (SRM) method working in negative mode was developed. Ion transitions were based on ionization and fragmentation behaviour of sulfate metabolites as well as specific neutral losses (NL of 15 Da and NL of 36 Da) of compounds with related chemical structure. Six sulfate metabolites were detected after the analysis of excretion study samples. Three of the identified metabolites were characterized by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS). Results showed that five out of the six identified sulfate metabolites were detected in urine up to the last collected samples from both excretion studies. Copyright © 2016 John Wiley & Sons, Ltd.

LC-MS/MS detection of unaltered glucuronoconjugated metabolites of metandienone

The aim of this study was to evaluate the direct detection of glucuronoconjugated metabolites of metandienone (MTD) and their detection times. Metabolites resistant to enzymatic hydrolysis were also evaluated. Based on the common mass spectrometric behaviour of steroid glucuronides, three liquid chromatography-tandem mass spectrometry (LC-MS/MS) strategies were applied for the detection of unpredicted and predicted metabolites: precursor ion scan (PI), neutral loss scan (NL), and theoretical selected reaction monitoring (SRM) methods. Samples from four excretion studies of MTD were analyzed for both the detection of metabolites and the establishment of their detection times. Using PI and NL methods, seven metabolites were observed in post-administration samples. SRM methods allowed for the detection of 13 glucuronide metabolites. The detection times, measured by analysis with an SRM method, were between 1 and 22 days. The metabolite detected for the longest time was 18-nor-17β-hydroxymethyl-17α-methyl-5β-androsta-1,4,13-triene-3-one-17-glucuronide. One metabolite was resistant to hydrolysis with β-glucuronidase; however it was only detected in urine up to four days after administration. The three glucuronide metabolites with the highest retrospectivity were identified by chemical synthesis or mass spectrometric data, and although they were previously reported, this is the first time that analytical data of the intact phase II metabolites are presented for some of them. The LC-MS/MS strategies applied have demonstrated to be useful for detecting glucuronoconjugated metabolites of MTD, including glucuronides resistant to enzymatic hydrolysis which cannot be detected by conventional approaches. Copyright © 2016 John Wiley & Sons, Ltd.

A simple method for the small scale synthesis and solid-phase extraction purification of steroid sulfates

Steroid sulfates are a major class of steroid metabolite that are of growing importance in fields such as anti-doping analysis, the detection of residues in agricultural produce or medicine. Despite this, many steroid sulfate reference materials may have limited or no availability hampering the development of analytical methods. We report simple protocols for the rapid synthesis and purification of steroid sulfates that are suitable for adoption by analytical laboratories. Central to this approach is the use of solid-phase extraction (SPE) for purification, a technique routinely used for sample preparation in analytical laboratories around the world. The sulfate conjugates of sixteen steroid compounds encompassing a wide range of steroid substitution patterns and configurations are prepared, including the previously unreported sulfate conjugates of the designer steroids furazadrol (17β-hydroxyandrostan[2,3-d]isoxazole), isofurazadrol (17β-hydroxyandrostan[3,2-c]isoxazole) and trenazone (17β-hydroxyestra-4,9-dien-3-one). Structural characterization data, together with NMR and mass spectra are reported for all steroid sulfates, often for the first time. The scope of this approach for small scale synthesis is highlighted by the sulfation of 1μg of testosterone (17β-hydroxyandrost-4-en-3-one) as monitored by liquid chromatography-mass spectrometry (LCMS).

Stereochemistry and Mechanism of Enzymatic and Non-Enzymatic Hydrolysis of Benzylic sec-Sulfate Esters

The substrate scope of inverting alkylsulfatase Pisa1 was extended towards benzylic sec-sulfate esters by suppression of competing non-enzymatic autohydrolysis by addition of dimethyl sulfoxide as co-solvent. Detailed investigation of the mechanism of autohydrolysis in ¹⁸O-labeled buffer by using an enantiopure sec-benzylic sulfate ester as substrate revealed that from the three possible pathways (i) inverting S_N2-type nucleophilic attack of [OH^–] at the benzylic carbon represents the major pathway, whereas (ii) S_N1-type formation of a planar benzylic carbenium ion leading to racemization was a minor event, and (iii) Retaining S_N2-type nucleophilic attack at sulfur took place at the limits of detection. The data obtained are interpreted by analysis of Hammett constants of meta substituents.

A new sulphate metabolite as a long-term marker of metandienone misuse

Metandienone is one of the most frequently detected anabolic androgenic steroids in sports drug testing. Metandienone misuse is commonly detected by monitoring different metabolites excreted free or conjugated with glucuronic acid using gas chromatography mass spectrometry (GC-MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS) after hydrolysis with β-glucuronidase and liquid-liquid extraction. It is known that several metabolites are the result of the formation of sulphate conjugates in C17, which are converted to their 17-epimers in urine. Therefore, sulphation is an important phase II metabolic pathway of metandienone that has not been comprehensively studied. The aim of this work was to evaluate the sulphate fraction of metandienone metabolism by LC-MS/MS. Seven sulphate metabolites were detected after the analysis of excretion study samples by applying different neutral loss scan, precursor ion scan and SRM methods. One of the metabolites (M1) was identified and characterised by GC-MS/MS and LC-MS/MS as 18-nor-17β-hydroxymethyl-17α-methylandrost-1,4,13-triene-3-one sulphate. M1 could be detected up to 26 days after the administration of a single dose of metandienone (5 mg), thus improving the period in which the misuse can be reported with respect to the last long-term metandienone metabolite described (18-nor-17β-hydroxymethyl-17α-methylandrost-1,4,13-triene-3-one excreted in the glucuronide fraction).

Alternative long-term markers for the detection of methyltestosterone misuse

Methyltestosterone (MT) is one of the most frequently detected anabolic androgenic steroids in doping control analysis. MT misuse is commonly detected by the identification of its two main metabolites excreted as glucuronide conjugates, 17α-methyl-5α-androstan-3α,17β-diol and 17α-methyl-5β-androstan-3α,17β-diol. The detection of these metabolites is normally performed by gas chromatography-mass spectrometry, after previous hydrolysis with β-glucuronidase enzymes, extraction and derivatization steps. The aim of the present work was to study the sulphate fraction of MT and to evaluate their potential to improve the detection of the misuse of the drug in sports. MT was administered to healthy volunteers and urine samples were collected up to 30days after administration. After an extraction with ethyl acetate, urine extracts were analysed by liquid chromatography tandem mass spectrometry using electrospray ionisation in negative mode by monitoring the transition m/z 385 to m/z 97. Three diol sulphate metabolites (S1, S2 and S3) were detected. Potential structures for these metabolites were proposed after solvolysis and mass spectrometric experiments: S1, 17α-methyl-5β-androstan-3α,17β-diol 3α-sulphate; S2, 17β-methyl-5α-androstan-3α,17α-diol 3α-sulphate; and S3, 17β-methyl-5β-androstan-3α,17α-diol 3α-sulphate. Synthesis of reference compounds will be required in order to confirm the structures. The retrospectivity of these sulphate metabolites in the detection of MT misuse was compared with the obtained with previously described metabolites. Metabolite S2 was detected up to 21days after MT administration, improving between 2 and 3 times the retrospectivity of the detection compared to the last long-term metabolite of MT previously described, 17α-hydroxy-17β-methylandrostan-4,6-dien-3-one.

Reaction of pregnenolone with cyanoacetylhydrazine: novel synthesis of hydrazide-hydrazone, pyrazole, pyridine, thiazole, thiophene derivatives and their cytotoxicity evaluations

Pregnenolone (1) was used as a template to develop new anticancer compounds. Ring D modification of 1 through its reaction with cyanoacetylhydrazine (2) gave the hydrazide-hydrazone derivative 3. The latter compound underwent heterocyclization reactions to give the pyrazole, pyridine, thiazole and thiophene derivatives of pregnenolone. The cytotoxicity of the newly synthesized heterocyclic steroids against three human tumor cell lines namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) were studied. Some of tested compounds were found to exhibit much higher inhibitory effects towards the three tumor cell lines than the reference drug, doxorubicin.

Schemes of metabolic patterns of anabolic androgenic steroids for the estimation of metabolites of designer steroids in human urine

Unified metabolism schemes of anabolic androgenic steroids (AAS) in human urine based on structure classification of parent molecules are presented in this paper. Principal components analysis (PCA) was applied to AAS molecules referred in the World Anti-Doping Agency (WADA) list of prohibited substances, resulting to their classification into six distinct groups related to structure features where metabolic alterations usually occur. The metabolites of the steroids participating to these six groups were treated using the Excel(c) classification filters showing that common metabolism routes are derived for each of the above PCA classes, leading to the proposed metabolism schemes of the present study. This rule-based approach is proposed for the prediction of the metabolism of unknown, chemically modified steroids, otherwise named as designer steroids. The metabolites of three known, in the literature, AAS are estimated using the proposed metabolism schemes, confirming that their use could be a useful tool for the prediction of metabolic pathways of unknown AAS.

The anabolic androgenic steroid oxandrolone in the treatment of wasting and catabolic disorders: review of efficacy and safety

There has been increasing interest in the development of effective agents that can be safely used to promote anabolism in the clinical setting for patients with chronic wasting conditions as well as in the prevention and treatment of frailty associated with loss of muscle tissue in aging (sarcopenia). One such agent is the anabolic androgenic steroid (AAS) oxandrolone, which has been used in such clinical situations as HIV-related muscle wasting, severe burn injury, trauma following major surgery, neuromuscular disorders and alcoholic hepatitis for over 30 years. In the US, oxandrolone is the only AAS that is US FDA-approved for restitution of weight loss after severe trauma, major surgery or infections, malnutrition due to alcoholic cirrhosis, and Duchenne's or Becker's muscular dystrophy. Our review of the use of oxandrolone in the treatment of catabolic disorders, HIV and AIDS-related wasting, neuromuscular and other disorders provides strong evidence of its clinical efficacy. Improvements in body composition, muscle strength and function, status of underlying disease or recovery from acute catabolic injury and nutritional status are significant in the vast majority of well designed trials. However, oxandrolone has not yet been studied in sarcopenia.Unlike other orally administered C17alpha-alkylated AASs, the novel chemical configuration of oxandrolone confers a resistance to liver metabolism as well as marked anabolic activity. In addition, oxandrolone appears not to exhibit the serious hepatotoxic effects (jaundice, cholestatic hepatitis, peliosis hepatis, hyperplasias and neoplasms) attributed to the C17alpha-alkylated AASs. Oxandrolone is reported to be generally well tolerated and the most commonly documented adverse effects are transient elevations in transaminase levels and reductions in high density lipoprotein cholesterol level.However, optimal risk:benefit ratios for oxandrolone and other agents in its class will need to be refined before widespread clinical acceptance of AASs as a therapeutic option in sarcopenia and other chronic wasting conditions.

Metabolism of methandrostenolone in the horse: a gas chromatographic-mass spectrometric investigation of phase I and phase II metabolism

The phase I and phase II metabolism of the anabolic steroid methandrostenolone was investigated following oral administration to a standardbred gelding. In the phase I study, metabolites were isolated from the urine by solid-phase extraction, deconjugated by acid catalysed methanolysis and converted to their O-methyloxime trimethylsilyl derivatives. GC-MS analysis indicated the major metabolic processes to be sequential reduction of the A-ring and hydroxylation at C6 and C16. In the phase II study, unconjugated, beta-glucuronidated and sulfated metabolites were fractionated and deconjugated using a combination of liquid-liquid extraction, enzyme hydrolysis, solid-phase extraction and acid catalysed methanolysis. Derivatization followed by GC-MS analysis revealed extensive conjugation to both glucuronic and sulfuric acids, with only a small proportion of metabolites occurring in unconjugated form.

Long-term detection and identification of metandienone and stanozolol abuse in athletes by gas chromatography-high-resolution mass spectrometry

The misuse of anabolic androgenic steroids (AAS) in human sports is controlled by gas chromatography-mass spectrometric analysis of urine specimens obtained from athletes. The analysis is improved with modern high-resolution mass spectrometry (HRMS). The detection and identification of metabolites of stanozolol (I) [3'-hydroxystanozolol (II) and 4 beta-hydroxystanozolol (III)] and metandienone (IV) I17 beta-methyl-5 beta-androst-1-ene-3 alpha,17 alpha-diol (V) and 18-nor-17,17-dimethyl-5 beta-androsta-1,13-dien-3 alpha-ol (VI)] with GC-HRMS at 3000 resolution yielded a large increase in the number of positive specimens. A total of 116 anabolic steroid positives were found in this laboratory in 1995 via GC-MS and GC-HRMS screening of 6700 human urine specimens collected at national and international sporting events and at out-of-competition testing. Of the 116 positive cases, 41 were detected using conventional (quadrupole) GC-MS screening. The other 75 positives were identified via GC-HRMS screening. To confirm the HRMS screening result, the urine sample was reanalyzed using a specific sample workup procedure to selectively isolate the metabolites of the identified substance. II and III were selectively isolated via immunoaffinity chromatography (IAC) using an antibody which was prepared for methyltestosterone and shows high cross reactivity to II and III. V and VI were isolated using high-performance liquid chromatography (HPLC) fractionation.

Testing for natural and synthetic anabolic agents in human urine

This paper describes a comprehensive method for the detection of natural and synthetic anabolic agents, including some veterinary preparations such as trenbolone, zeranol (a non-steroidal agent) and clenbuterol (a beta 2-agonist). For the natural steroids such as testosterone, the precise determination of urinary androgens during routine procedures allowed the description of statistical distribution of relevant parameters of the endogenous steroid profile amongst male athletes. The validity of the results is discussed, taking into account some factors that may cause the degradation of the specimen.