A screening method for the quantitative determination of selective androgen receptor modulators (SARMs) in capsules by high resolution 19F- and 1H-NMR spectroscopy

A new method for rapid determination of the content of selective androgenic receptor modulators (SARMs) andarine, cardarine, ligandrol, ostarine and S-23 in capsules by 1H- and 19F-high resolution nuclear magnetic resonance spectroscopy was described and validated. Specificity, linearity, accuracy, precision, detection and quantification limits were considered as validation parameters. Full 1H-, 13C- and 19F-NMR structural assignment of the SARMs is provided as a tool for self-standing identification without a reference standard. Amounts of 7-15 mg of SARMs/capsule were detected in different products with an intermediate precision of 0.8-1.7% in 4 to 20 minutes of analysis time. The validation results and rapidity of analysis confirm the applicability of the method for large-scale screening. The statistical analysis of the results from 19F- and 1H-quantitative NMR showed that both approaches were equally effective, thus expanding the potential use of the methodology to non-fluorinated SARMs. At present, no SARM has been approved for human consumption; however, SARMs are actually used by bodybuilders and recreational athletes, who purchase them even though the risk-benefit ratio of these molecules has not been definitively established.

Androgens, sports, and detection strategies for anabolic drug use

For decades, anabolic androgenic agents have represented the substance class most frequently observed in doping control samples. They comprise synthetic and pseudoendogenous anabolic androgenic steroids and other, mostly non-steroidal compounds with (presumed) positive effects on muscle mass and function. While exogenous substances can easily be detected by gas/liquid chromatography and mass spectrometry, significantly more complex methodologies including the longitudinal monitoring of individual urinary steroid concentrations/ratios and isotope ratio mass spectrometry are required to provide evidence for the exogenous administration of endogenous compounds. This narrative review summarizes the efforts made within the last 5 years to further improve the detection of anabolic agents in doping control samples. Different approaches such as the identification of novel metabolites and biomarkers, the acquisition of complementary mass spectrometric data, and the development of new analytical strategies were employed to increase method sensitivity and retrospectivity while simultaneously reducing method complexity to facilitate a higher and faster sample throughput.

Detection of DHCMT long-term metabolite glucuronides with LC-MSMS as an alternative approach to conventional GC-MSMS analysis

Dehydrochloromethyltestosterone (DHCMT) is one of the most detected illicit used anabolic-androgenic steroids in professional sports. Therefore, a fast and accurate analysis of this substance is of great importance for a constructive fight against doping abuse. The conventional method for the analysis of this drug, GC-MSMS, is very sensitive and selective but also very time- and resource-consuming. With the presented work, a new approach for simple detection with LC-HRMSMS without any sample preparation is introduced. The method is based on the direct analysis of two newly described phase-II metabolites of the DHCMT long-term metabolite 4-chloro-18-nor-17β-hydroxymethyl-17α-methyl-5β-androst-13-en-3α-ol (M3). LC-HRMSMS, GC-MSMS, fractionation and derivatization experiments are combined to identify and characterize for the first time two different glucuronide-acid conjugates of this metabolite in positive human urine samples. In addition, a third glucuronide metabolite was identified, however without isomeric structure determination. The detection of these metabolites is particularly interesting for confirmation analyses, as the method is rapid and requires little sample material.

Structurally different anabolic androgenic steroids reduce neurite outgrowth and neuronal viability in primary rat cortical cell cultures

The illicit use of anabolic androgenic steroids (AAS) among adolescents and young adults is a major concern due to the unknown and unpredictable impact of AAS on the developing brain and the consequences of this on mental health, cognitive function and behaviour. The present study aimed to investigate the effects of supra-physiological doses of four structurally different AAS (testosterone, nandrolone, stanozolol and trenbolone) on neurite development and cell viability using an in vitro model of immature primary rat cortical cell cultures. A high-throughput screening image-based approach, measuring the neurite length and number of neurons, was used for the analysis of neurite outgrowth. In addition, cell viability and expression of the Tubb3 gene (encoding the protein beta-III tubulin) were investigated. Testosterone, nandrolone, and trenbolone elicited adverse effects on neurite outgrowth as deduced from an observed reduced neurite length per neuron. Trenbolone was the only AAS that reduced the cell viability as indicated by a decreased number of neurons and declined mitochondrial function. Moreover, trenbolone downregulated the Tubb3 mRNA expression. The adverse impact on neurite development was neither inhibited nor supressed by the selective androgen receptor (AR) antagonist, flutamide, suggesting that the observed effects result from another mechanism or mechanisms of action that are operating apart from AR activation. The results demonstrate a possible AAS-induced detrimental effect on neuronal development and regenerative functions. An impact on these events, that are essential mechanisms for maintaining normal brain function, could possibly contribute to behavioural alterations seen in AAS users.

New Insights into the Metabolism of Methyltestosterone and Metandienone: Detection of Novel A-Ring Reduced Metabolites

Metandienone and methyltestosterone are orally active anabolic-androgenic steroids with a 17α-methyl structure that are prohibited in sports but are frequently detected in anti-doping analysis. Following the previously reported detection of long-term metabolites with a 17ξ-hydroxymethyl-17ξ-methyl-18-nor-5ξ-androst-13-en-3ξ-ol structure in the chlorinated metandienone analog dehydrochloromethyltestosterone ("oral turinabol"), in this study we investigated the formation of similar metabolites of metandienone and 17α-methyltestosterone with a rearranged D-ring and a fully reduced A-ring. Using a semi-targeted approach including the synthesis of reference compounds, two diastereomeric substances, viz. 17α-hydroxymethyl-17β-methyl-18-nor-5β-androst-13-en-3α-ol and its 5α-analog, were identified following an administration of methyltestosterone. In post-administration urines of metandienone, only the 5β-metabolite was detected. Additionally, 3α,5β-tetrahydro-epi-methyltestosterone was identified in the urines of both administrations besides the classical metabolites included in the screening procedures. Besides their applicability for anti-doping analysis, the results provide new insights into the metabolism of 17α-methyl steroids with respect to the order of reductions in the A-ring, the participation of different enzymes, and alterations to the D-ring.

A photochemical approach to 18-nor-17β-hydroxymethyl-17α-methylandrost-13-ene steroids

A photochemical approach to 18-nor-17β-hydroxymethyl-17α-methylandrost-13-ene unit of the long-term metabolites of 17-methylated androgenic anabolic steroids (AAS) is reported. It is based on a visible light-promoted radical decarboxylative alkynylation of steroidal redox-active ester. The developed method was used in synthesis of the long-term metabolite of AAS oxymesterone.

Development of a method using gas chromatography-mass spectrometry for profiling of oil-based androgenic anabolic steroid products

A GC-MS based analytical method was developed for the profiling of oil-based AAS products using 15 organic constituents as target compounds. A total of 219 compounds were identified in 109 seized AAS products, among them 15 target compounds were selected. The selection was based on each compound's occurrence, reproducibility, and variance between products. The 15 target compounds did not include the active steroid itself, but only compounds found in the carrier oil. The subsequent method validation included assessment of specificity, linearity, precision, robustness and sample stability. The method was finally applied for the classification of a set of 27 seizures of AAS products supplied by the police. The classification was based on the Pearson correlation coefficient using pre-treated peak area data from the 15 target compounds. A successful classification was obtained, with only a small overlap between linked and unlinked samples. A 1% false-positive rate could be obtained at a threshold of 0.625 in terms of the Pearson distance. The present study thus demonstrates that it is possible to profile and classify AAS products with regard to a common origin. As the profiling method is not specific with regards to the steroid content, it may potentially be used to profile and compare other kinds of oil-based liquids.

The synthesis of 4-chloro-17β-hydroxymethyl-17α-methyl-18-norandrosta-4,13-diene-3α-ol - Proposed long term metabolite (M4) of oralturinabol

4-Chloro-17β-hydroxymethyl-17α-methyl-18-norandrosta-4,13-diene-3α-ol is one of proposed long term metabolites of oralturinabol (anabolic androgenic steroid restricted in sport). The synthesis of 4-chloro-17β-hydroxymethyl-17α-methyl-18-norandrosta-4,13-diene-3α-ol was achieved. Isomerisation of configuration of 13-carbon was used for construction of 17β-hydroxymethyl-17α-methyl fragment. The proposed route of synthesis allows to obtain 3β-hydroxy isomer as well.

Design, synthesis and characterization of a PEGylated stanozolol for potential therapeutic applications

Stanozolol (STZ) is a drug used to treat serious disorders like aplastic anemia and hereditary angioedema. It is also indicated as an adjunct therapy for the treatment of vascular disorders and growth failures. Encouraging results obtained using animal models demonstrated that STZ increases bone formation and mineralization, thus improving both density and biomechanical properties. Like natural androgens, such as TST and 5α-dihydrotestosterone (5α-DHT), STZ binds androgen receptor (AR) to activate AR-mediated signaling. Despite its therapeutic effects, this synthetic anabolic-androgenic steroid (AAS), or 5α-DHT derivative, due to its high lipophilicity, is poor soluble in water. Thus, to increase the water solubility and stability of STZ, as well as its bioavailability and efficacy, an innovative PEGylated STZ (STZ conjugated with (MeO-PEG-NH₂)_10kDa, (MeO-PEG-NH)_10kDa-STZ) was synthesized. As confirmed by chromatography (RP-HPLC) and spectrometry (ATR-FTIR, ¹H NMR, elemental CHNS(O) analysis, MALDI-TOF/TOF) analyses, a very pure, stable and soluble compound was obtained. Acetylcholinesterase (AChE) competitive ELISA demonstrated that the resulting PEGylated STZ competes against biological TST, especially at lower concentrations. Cytotoxicity of increasing concentrations (1, 10, 25 or 50 µM) of STZ and/or (MeO-PEG-NH)_10kDa-STZ was also evaluated for up 80 h by performing the MTT assay on human osteosarcoma Saos-2 cells, which express AR and are responsive to STZ. PEGylation mitigated cytotoxicity of STZ, by increasing the cell viability values, especially at higher drug concentrations. Furthermore, these results suggest that (MeO-PEG-NH)_10kDa-STZ is a promising and reliable drug to be used in clinical conditions in which TST is required.

Doping substances in dietary supplements

BACKGROUND

International studies have shown that 12-58 % of all dietary supplements intended for people who exercise and engage in sports contain substances prohibited by the World Anti-Doping Code (WADC). In some cases, the doping substances are not declared on the product label, and the consumer may therefore be unaware of what he/she ingests. Many of the substances may cause adverse health effects, and sale of such products is illegal in Norway.

MATERIAL AND METHOD

To investigate the prevalence of doping substances in dietary supplements sold on the Norwegian market, a total of 93 high-risk products from online shops targeting Norwegian consumers were analysed for substances on the WADC Prohibited List and pharmaceutical drugs. All supplements were marketed as able to boost energy levels and/or having a muscle-building or fat-burning effect. The products were selected on the basis of tips received, online forums and/or international lists.

RESULTS

Altogether 21 of 93 (23 %) products analysed contained prohibited substances, pharmaceutical drugs and/or illegal amounts of caffeine. Substances on the WADC Prohibited List were detected in 8 of the 93 (9 %) dietary supplements. All products containing doping substances were declared as containing one or more banned substances.

INTERPRETATION

The results show that using apparently legal dietary supplements purchased in online shops targeting Norwegian consumers involves a risk of inadvertent doping and adverse health effects.

Development of an extraction method for anabolic androgenic steroids in dietary supplements and analysis by gas chromatography-mass spectrometry: Application for doping-control

Several studies have highlighted that nutritional supplements may contain undeclared anabolic steroids that are banned by the International Olympic Committee/World Anti-Doping Agency. Any kind of abuse with these drugs is extremely dangerous because of their side effects. Thus, the control of food additives in order to protect the best consumer health and to limit fraudulent practices in the field of sports is essential. This paper describes a simple and effective qualitative gas chromatography-mass spectrometry (GC-MS) method to detect anabolic androgenic steroids (AAS): androsterone, nandrolene, dehydroepiandrosterone, 5ɑ-androstane-3β, 17β-diol, dihydrotestosterone, testosterone, methenolone acetate, methandienone, boldenone and fluoxymesterone, in food supplements. Methyltestosterone was used as internal standard. Target compounds were extracted with a mixture of N-pentane and di-ethylether (7.5:2.5, v/v). A good extraction recovery was obtained by our method for all the AAS (R > 88%). Crude extract was derivatized with N-methyl-N-trimethylsilyl-trifluoracetamide. Separation was performed on a GC connected to quadrupole MS detector using a 5% phenylmethylsiloxane fused silica capillary column (30 m × 0.25 mm i.d.; film thickness, 0.25 µm). Helium was used as carrier gas with a flow rate of 0.3 µl min^-1 (measured at 6.1 psi 190 °C). The MS was operated in electron ionization mode (70 eV) and in selected ion monitoring (SIM). The mass spectra of the standard compounds were acquired in full SCAN mode (50-700 m/z) by infusion of a reference solution at 50 µg/ml. Three higher diagnostic ions were monitored for each compound of interest. All AAS get separated with good peak shapes and resolution factor. The total analysis time by our optimised method was only 20 min. The developed method was validated according to Laboratories International Standard regulations for specificity, precision in both liquid and solid matrixes, and memory effect. The Tolerance Interval was judged true. The limit of detection was about 10 ng/g for solid samples and 10 ng/ml for liquid samples. The developed method was then applied to the research of steroids in nine Tunisian commercially dietary supplements using for each compound of interest SIM mode for screening then SCAN mode for confirmation. One of the monitoring samples was positive to methandienone not declared on the label. Our analytical method can be beneficial for AAS screening in dietary supplements.

Chemical Composition and Labeling of Substances Marketed as Selective Androgen Receptor Modulators and Sold via the Internet

IMPORTANCE

Recent reports have described the increasing use of nonsteroidal selective androgen receptor modulators, which have not been approved by the US Food and Drug Administration (FDA), to enhance appearance and performance. The composition and purity of such products is not known.

OBJECTIVE

To determine the chemical identity and the amounts of ingredients in dietary supplements and products marketed and sold through the internet as selective androgen receptor modulators and compare the analyzed contents with product labels.

DESIGN AND SETTING

Web-based searches were performed from February 18, 2016, to March 25, 2016, using the Google search engine on the Chrome and Internet Explorer web browsers to identify suppliers selling selective androgen receptor modulators. The products were purchased and the identities of the compounds and their amounts were determined from April to August 2016 using chain-of-custody and World Anti-Doping Association-approved analytical procedures. Analytical findings were compared against the label information.

EXPOSURES

Products marketed and sold as selective androgen receptor modulators.

MAIN OUTCOMES AND MEASURES

Chemical identities and the amount of ingredients in each product marketed and sold as selective androgen receptor modulators.

RESULTS

Among 44 products marketed and sold as selective androgen receptor modulators, only 23 (52%) contained 1 or more selective androgen receptor modulators (Ostarine, LGD-4033, or Andarine). An additional 17 products (39%) contained another unapproved drug, including the growth hormone secretagogue ibutamoren, the peroxisome proliferator-activated receptor-δ agonist GW501516, and the Rev-ErbA agonist SR9009. Of the 44 tested products, no active compound was detected in 4 (9%) and substances not listed on the label were contained in 11 (25%). In only 18 of the 44 products (41%), the amount of active compound in the product matched that listed on the label. The amount of the compounds listed on the label differed substantially from that found by analysis in 26 of 44 products (59%).

CONCLUSIONS AND RELEVANCE

In this limited investigation involving chemical analyses of 44 products marketed as selective androgen receptor modulators and sold via the internet, most products contained unapproved drugs and substances. Only 52% contained selective androgen receptor modulators and many were inaccurately labeled.

3-Piperidylethoxypterocarpan: A potential bone anabolic agent that improves bone quality and restores trabecular micro-architecture in ovariectomized osteopenic rats

A series of new 6H-benzofuro[3, 2-c]chromenes (BFC, pterocarpans) with structure-activity relationships were investigated for their potential use in osteoporosis treatment. One of the BFCs 3-piperidylethoxypterocarpan 20 promotes osteoblast differentiation and mineralization at a dose as low as 1 pM via activation of ER/P38MAPK/BMP-2 pathway. When evaluated for in-vivo osteogenic activity in female Sprague-Dawley rats, BFC 20 increased bone mineral density and new bone formation, compared with control at 1.0 and 10.0 mg/kg/body weight by oral gavage for 30 days. The compound was devoid of any uterotrophic effect and led to the new bone formation in adult ovariectomized osteopenic rats. BFC 20 compound also inhibited bone resorption by reducing Ovx induced increase in urinary CTx, thus exhibiting both bone anabolic and anti-catabolic action. Finally, BFC 20 treatment to Ovx rats led to improved trabecular microarchitectural restoration and exhibited therapeutic potential as a dual acting anti-osteoporotic agent for the management of osteoporosis.

In silico discovery of substituted pyrido[2,3-d]pyrimidines and pentamidine-like compounds with biological activity in myotonic dystrophy models

Myotonic dystrophy type 1 (DM1) is a rare multisystemic disorder associated with an expansion of CUG repeats in mutant DMPK (dystrophia myotonica protein kinase) transcripts; the main effect of these expansions is the induction of pre-mRNA splicing defects by sequestering muscleblind-like family proteins (e.g. MBNL1). Disruption of the CUG repeats and the MBNL1 protein complex has been established as the best therapeutic approach for DM1, hence two main strategies have been proposed: targeted degradation of mutant DMPK transcripts and the development of CUG-binding molecules that prevent MBNL1 sequestration. Herein, suitable CUG-binding small molecules were selected using in silico approaches such as scaffold analysis, similarity searching, and druggability analysis. We used polarization assays to confirm the CUG repeat binding in vitro for a number of candidate compounds, and went on to evaluate the biological activity of the two with the strongest affinity for CUG repeats (which we refer to as compounds 1–2 and 2–5) in DM1 mutant cells and Drosophila DM1 models with an impaired locomotion phenotype. In particular, 1–2 and 2–5 enhanced the levels of free MBNL1 in patient-derived myoblasts in vitro and greatly improved DM1 fly locomotion in climbing assays. This work provides new computational approaches for rational large-scale virtual screens of molecules that selectively recognize CUG structures. Moreover, it contributes valuable knowledge regarding two compounds with desirable biological activity in DM1 models.

Anabolic androgenic steroid-induced hepatotoxicity

Anabolic androgenic steroids (AAS) have been abused for decades by both professional and amateur athletes in order to improve physical performance or muscle mass. AAS abuse can cause adverse effects, among which are hepatotoxic effects. These effects include cholestatic icterus and possibly peliosis hepatis and hepatocellular carcinoma or adenoma. In particular, 17α-alkylated AAS appear to be hepatotoxic, whereas nonalkylated AAS appear not to be. The 17α-alkyl substitution retards hepatic metabolism of the AAS rendering it orally bioavailable. The mechanism responsible for the hepatotoxicity induced by 17α-alkylated AAS remains poorly understood. However, oxidative stress has been repeatedly shown to be associated with it. In this manuscript we present a hypothesis which describes a potential mechanism responsible for AAS-induced hepatotoxicity, based on several observations from the literature which suggest oxidative stress being a causal factor.

Investigation of the selective androgen receptor modulators S1, S4 and S22 and their metabolites in equine plasma using high-resolution mass spectrometry

RATIONALE

Selective androgen receptor modulators (SARMs) are prohibited in sports due to their performance enhancing ability. It is important to investigate the metabolism to determine appropriate targets for doping control. This is the first study where the equine metabolites of SARMs S1, S4 (Andarine) and S22 (Ostarine) have been studied in plasma.

METHODS

Each SARM was administered to three horses as an intravenous bolus dose and plasma samples were collected. The samples were pretreated with protein precipitation using cold acetonitrile before separation by liquid chromatography. The mass spectrometric analysis was performed using negative electrospray, quadrupole time-of-flight mass spectrometry operated in MS(E) mode and triple-quadrupole mass spectrometry operated in selected reaction monitoring mode. For the quantification of SARM S1, a deuterated analogue was used as internal standard.

RESULTS

The numbers of observed metabolites were eight, nine and four for the SARMs S1, S4 and S22, respectively. The major metabolite was formed by the same metabolic reactions for all three SARMs, namely amide hydrolysis, hydroxylation and sulfonation. The values of the determined maximum plasma concentrations were in the range of 97-170 ng/mL for SARM S1, 95-115 ng/mL for SARM S4 and 92-147 ng/mL for SARM S22 and the compounds could be detected for 96 h, 12 h and 18 h, respectively.

CONCLUSIONS

The maximum plasma concentration of SARMs S1, S4 and S22 was measured in the first sample (5 min) after administration and they were eliminated fast from plasma. The proposed targets to be used in equine doping control are the parent compounds for all three SARMs, but with the metabolite yielding the highest response as a complementary target. Copyright © 2016 John Wiley & Sons, Ltd.

Gas chromatography/chemical ionization triple quadrupole mass spectrometry analysis of anabolic steroids: ionization and collision-induced dissociation behavior

RATIONALE

The detection of new anabolic steroid metabolites and new designer steroids is a challenging task in doping analysis. Switching from electron ionization gas chromatography triple quadrupole mass spectrometry (GC/EI-MS/MS) to chemical ionization (CI) has proven to be an efficient way to increase the sensitivity of GC/MS/MS analyses and facilitate the detection of anabolic steroids. CI also extends the possibilities of GC/MS/MS analyses as the molecular ion is retained in its protonated form due to the softer ionization. In EI it can be difficult to find previously unknown but expected metabolites due to the low abundance or absence of the molecular ion and the extensive (and to a large extent unpredictable) fragmentation. The main aim of this work was to study the CI and collision-induced dissociation (CID) behavior of a large number of anabolic androgenic steroids (AAS) as their trimethylsilyl derivatives in order to determine correlations between structures and CID fragmentation. Clarification of these correlations is needed for the elucidation of structures of unknown steroids and new metabolites.

METHODS

The ionization and CID behavior of 65 AAS have been studied using GC/CI-MS/MS with ammonia as the reagent gas. Glucuronidated AAS reference standards were first hydrolyzed to obtain their free forms. Afterwards, all the standards were derivatized to their trimethylsilyl forms. Full scan and product ion scan analyses were used to examine the ionization and CID behavior.

RESULTS

Full scan and product ion scan analyses revealed clear correlations between AAS structure and the obtained mass spectra. These correlations were confirmed by analysis of multiple hydroxylated, methylated, chlorinated and deuterated analogs.

CONCLUSIONS

AAS have been divided into three groups according to their ionization behavior and into seven groups according to their CID behavior. Correlations between fragmentation and structure were revealed and fragmentation pathways were postulated.

Stereocontrolled synthesis of the four 16-hydroxymethyl-19-nortestosterone isomers and their antiproliferative activities

Novel 16-hydroxymethyl-19-nortestosterone diastereomers were prepared by Birch reduction from the corresponding 3-methoxy-16-hydroxymethylestra-1,3,5(10)-trien-17-ol isomers with known configurations. The synthesized compounds are 16α- and 16β-hydroxymethyl-substituted 19-nortestosterone and their 17α-epimers. To prepare 17α-19-nortestosterone, the Mitsunobu inversion reaction of 19-nortestosterone with different alkyl and aryl carboxylic acids was chosen. Deacylation of the new compounds by the Zemplén method yielded the required 17α-19-nortestosterone. The antiproliferative activities of the structurally related compounds were determined in vitro through microculture tetrazolium assays on a panel of human adherent cervical (HeLa, SiHa and C33A), breast (MCF-7, MDA-MB-231, MDA-MB-361 and T47D) and ovarian (A2780) cell lines. The 17α epimer of 19-nortestosterone demonstrated considerable activity, selectively for HeLa cells, with a calculated IC50 of 0.65 μM. The reference compound, cisplatin, displayed an order of magnitude higher IC50 (12.4 μM). The cancer selectivity of 17α-19-nortestosterone was tested by MTT assay performed with noncancerous human fibroblast cell line MRC-5. The results indicated that 17α-19-nortestosterone selectively disturbs the viability of HeLa cells without greatly affecting other cancer cell types and intact fibroblasts.

Oxidation of the aromatic amino acids tryptophan and tyrosine disrupts their anabolic effects on bone marrow mesenchymal stem cells

Age-induced bone loss is associated with greater bone resorption and decreased bone formation resulting in osteoporosis and osteoporosis-related fractures. The etiology of this age-induced bone loss is not clear but has been associated with increased generation of reactive oxygen species (ROS) from leaky mitochondria. ROS are known to oxidize/damage the surrounding proteins/amino acids/enzymes and thus impair their normal function. Among the amino acids, the aromatic amino acids are particularly prone to modification by oxidation. Since impaired osteoblastic differentiation from bone marrow mesenchymal stem cells (BMMSCs) plays a role in age-related bone loss, we wished to examine whether oxidized amino acids (in particular the aromatic amino acids) modulated BMMSC function. Using mouse BMMSCs, we examined the effects of the oxidized amino acids di-tyrosine and kynurenine on proliferation, differentiation and Mitogen-Activated Protein Kinase (MAPK) pathway. Our data demonstrate that amino acid oxides (in particular kynurenine) inhibited BMMSC proliferation, alkaline phosphatase expression and activity and the expression of osteogenic markers (Osteocalcin and Runx2). Taken together, our data are consistent with a potential pathogenic role for oxidized amino acids in age-induced bone loss.

Characterization of a non-approved selective androgen receptor modulator drug candidate sold via the Internet and identification of in vitro generated phase-I metabolites for human sports drug testing

RATIONALE

Potentially performance-enhancing agents, particularly anabolic agents, are advertised and distributed by Internet-based suppliers to a substantial extent. Among these anabolic agents, a substance referred to as LGD-4033 has been made available, comprising the core structure of a class of selective androgen receptor modulators (SARMs).

METHODS

In order to provide comprehensive analytical data for doping controls, the substance was obtained and characterized by nuclear magnetic resonance spectroscopy (NMR) and liquid chromatography/electrospray ionization high resolution/high accuracy tandem mass spectrometry (LC/ESI-HRMS). Following the identification of 4-(2-(2,2,2-trifluoro-1-hydroxyethyl)pyrrolidin-1-yl)-2-(trifluoromethyl)benzonitrile, the substance was subjected to in vitro metabolism studies employing human liver microsomes and Cunninghamella elegans (C. elegans) preparations as well as electrochemical metabolism simulations.

RESULTS

By means of LC/ESI-HRMS, five main phase-I metabolites were identified as products of liver microsomal preparations including three monohydroxylated and two bishydroxylated species. The two most abundant metabolites (one mono- and one bishydroxylated product) were structurally confirmed by LC/ESI-HRMS and NMR. Comparing the metabolic conversion of 4-(2-(2,2,2-trifluoro-1-hydroxyethyl)pyrrolidin-1-yl)-2-(trifluoromethyl)benzonitrile observed in human liver microsomes with C. elegans and electrochemically derived metabolites, one monohydroxylated product was found to be predominantly formed in all three methodologies.

CONCLUSIONS

The implementation of the intact SARM-like compound and its presumed urinary phase-I metabolites into routine doping controls is suggested to expand and complement existing sports drug testing methods.

Androgenic-anabolic activities of some new synthesized steroidal pyrane, pyridine and thiopyrimidine derivatives

In continuation of our previous work, fused steroidal derivatives with pyrane, pyridine, pyrimidine moieties were synthesized and evaluated as androgenic-anabolic agents. Some of the newly synthesized compounds are exhibited pronounced androgenic-anabolic activities.

Identification of an anabolic selective androgen receptor modulator that actively induces death of androgen-independent prostate cancer cells

Prostate cancer (PCa) initially responds to inhibition of androgen receptor (AR) signaling, but inevitably progresses to hormone ablation-resistant disease. Much effort is focused on optimizing this androgen deprivation strategy by improving hormone depletion and AR antagonism. However we found that bicalutamide, a clinically used antiandrogen, actually resembles a selective AR modulator (SARM), as it partially regulates 24% of endogenously 5α-dihydrotestosterone (DHT)-responsive genes in AR(+) MDA-MB-453 breast cancer cells. These data suggested that passive blocking of all AR functions is not required for PCa therapy. Hence, we adopted an active strategy that calls for the development of novel SARMs, which induce a unique gene expression profile that is intolerable to PCa cells. Therefore, we screened 3000 SARMs for the ability to arrest the androgen-independent growth of AR(+) 22Rv1 and LNCaP PCa cells but not AR(-) PC3 or DU145 cells. We identified only one such compound; the 4-aza-steroid, MK-4541, a potent and selective SARM. MK-4541 induces caspase-3 activity and cell death in both androgen-independent, AR(+) PCa cell lines but spares AR(-) cells or AR(+) non-PCa cells. This activity correlates with its promoter context- and cell-type dependent transcriptional effects. In rats, MK-4541 inhibits the trophic effects of DHT on the prostate, but not the levator ani muscle, and triggers an anabolic response in the periosteal compartment of bone. Therefore, MK-4541 has the potential to effectively manage prostatic hypertrophic diseases owing to its antitumor SARM-like mechanism, while simultaneously maintaining the anabolic benefits of natural androgens.

Tryptophan hydroxylase 1 (Tph-1)-targeted bone anabolic agents for osteoporosis

Tryptophan hydroxylase 1 (Tph-1), the principal enzyme for peripheral serotonin biosynthesis, provides a novel target to design anabolic agents for osteoporosis. Here, we present a design, synthesis of a novel series of ursolic acid derivatives under the guidance of docking technique, and bioevaluation of the derivatives using RBL2H3 cells and ovariectomized (OVX) rats. Of the compounds, 9a showed a potent inhibitory activity on serotonin biosynthesis. Further investigations revealed that 9a, as an efficient Tph-1 binder identified by SPR (estimated KD: 6.82 μM), suppressed the protein and mRNA expressions of Tph-1 and lowered serotonin contents in serum and gut without influence on brain serotonin. Moreover, oral administration of 9a elevated serum level of N-terminal propeptide of procollagen type 1 (P1NP), a bone formation marker, and improved bone microarchitecture without estrogenic side effects in ovariectomized rats. Collectively, 9a may serve as a new candidate for bone anabolic drug discovery.

Mass spectrometric behavior of anabolic androgenic steroids using gas chromatography coupled to atmospheric pressure chemical ionization source. Part I: ionization

The detection of anabolic androgenic steroids (AAS) is one of the most important topics in doping control analysis. Gas chromatography coupled to (tandem) mass spectrometry (GC-MS(/MS)) with electron ionization and liquid chromatography coupled to tandem mass spectrometry have been traditionally applied for this purpose. However, both approaches still have important limitations, and, therefore, detection of all AAS is currently afforded by the combination of these strategies. Alternative ionization techniques can minimize these drawbacks and help in the implementation of a single method for the detection of AAS. In the present work, a new atmospheric pressure chemical ionization (APCI) source commercialized for gas chromatography coupled to a quadrupole time-of-flight analyzer has been tested to evaluate the ionization of 60 model AAS. Underivatized and trimethylsylil (TMS)-derivatized compounds have been investigated. The use of GC-APCI-MS allowed for the ionization of all AAS assayed irrespective of their structure. The presence of water in the source as modifier promoted the formation of protonated molecules ([M+H](+)), becoming the base peak of the spectrum for the majority of studied compounds. Under these conditions, [M+H](+), [M+H-H2O](+) and [M+H-2·H2O](+) for underivatized AAS and [M+H](+), [M+H-TMSOH](+) and [M+H-2·TMSOH](+) for TMS-derivatized AAS were observed as main ions in the spectra. The formed ions preserve the intact steroid skeleton, and, therefore, they might be used as specific precursors in MS/MS-based methods. Additionally, a relationship between the relative abundance of these ions and the AAS structure has been established. This relationship might be useful in the structural elucidation of unknown metabolites.

Influences of musk administration on the doping test

Musk is widely used as a traditional drug in Asia for the treatment of stroke, tumour, and cardiopathy with an oral dosage of 0.03-0.1 g per day. Because of the potential anabolic effect, musk preparations have been included in the list of medical products containing prohibited substances employed for doping. The application of musk pod formulation was regarded as the reason of some adverse analytical findings in the 2011 FIFA Women's World Cup. In order to investigate the influence of musk administration on the doping test, we executed a chemical analysis and excretion study. The gas chromatography/mass spectrometry (GC-MS) analysis demonstrated the diversity of steroid concentrations in musk samples. Furthermore, the δ(13)C-values of steroids from wild deer musk showed more depleted than those of domestic deer musk by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) analysis. Because the steroids from some musk had δ(13)C-values in the range of naturally produced steroids in human body, the possible abuse of this kind of musk is very hard to be detected by isotope ratio mass spectrometry (IRMS) in doping control. Musk grains from wild and domestic deer were administrated for the excretion study respectively. Spot urine samples were collected from two male volunteers before and after 100 mg musk grains administration. The profiles and carbon isotope ratios of urinary steroids were determined by GC-MS and GC/C/IRMS. The ingestion of either wild or domestic deer musk did not lead to the adverse analytical finding of doping control in the single dosage of 100mg.

Integration of ligand and structure-based virtual screening for identification of leading anabolic steroids

Parallel ligand- and structure-based virtual screenings of 269 steroids with anabolic activity evaluated in vivo were performed. The quantitative structure-activity relationship (QSAR) model expressed by selected descriptors as the octanol-water partition coefficient, the molar volume and the quantum mechanical calculated charge values on atoms C1, C2, C5, C9, C10, C14 and C17 of the steroid skeleton, expresses structural features of anabolic steroids (AS) contributing to the transport and steroid-receptor interaction. On the other hand, computational simulations of a candidate ligand binding to a receptor study (a "docking" procedure) predict the association of these AS with the human androgen receptor (AR). Fourteen compounds were identified as lead; the most potent was the 7α-methylestr-4-en-3, 17-dione. It was concluded that a good anabolic activity requires hydrogen bonding interactions between both Arg752 and Gln711 residues in the cycles A with O3 atom of the steroid and either Asn705 and Thr877 residues in the cycles D of steroid with O17 atom.

Hydrogen isotope ratio mass spectrometry and high-resolution/high-accuracy mass spectrometry in metabolite identification studies: detecting target compounds for sports drug testing

RATIONALE

In sports drug testing, comprehensive studies on the metabolism of therapeutic agents with misuse potential are necessary to identify metabolites that provide utmost retrospectivity and specificity. By commonly employed approaches minor and/or long-term metabolites in urine might remain undetected. Hence, an alternative strategy to unambiguously identify the majority of urinary metabolites including low-abundance representatives is desirable.

METHODS

Urine samples were collected for 20 days during an elimination study with an oral dose of 5 mg of 17α-C(2)H3-metandienone. The specimens were processed according to established sample preparation procedures (including fractionation and deconjugation) and subjected to gas chromatography/hydrogen isotope ratio mass spectrometry (GC/IRMS) analysis. Due to the deuteration of the administered drug, urinary metabolites bearing the deuterium label yield abundant and specific signals on the GC/IRMS instrument resulting from the substantially altered (2)H/(1)H ratio. The sample aliquots were measured by gas chromatography/time-of-flight (GC/Q-TOF) mass spectrometry using identical GC conditions, allowing high-resolution/high-accuracy mass data to be obtained on all urinary metabolites previously identified by IRMS.

RESULTS

Within the IRMS chromatograms, labeled metabolites were identified up to 20 days after administration at urinary concentration down to 0.25 ng/mL. More than 50 metabolites were observed with the earlier described long-term metabolite of metandienone, 18-nor-17β-hyroxymethyl,17α-methyl-androst-1,4,13-trien-3-one, being the most prominent glucuronidated metabolite in the studied time window. In the sulfoconjugated steroids fraction, a yet unknown metabolite was observed at m/z 283.1997 comprising the experimentally determined elemental composition of C20H21(2)H3O.

CONCLUSIONS

Combining IRMS with high-resolution mass spectrometry considerably facilitates and accelerates metabolite identification of deuterium-labeled compounds in urine. Of particular relevance in doping control, the principle is applicable also to other arenas of drug research, allowing the preparation and administration of e.g. radioactively labeled substances to be omitted.

Detection and mass spectrometric characterization of novel long-term dehydrochloromethyltestosterone metabolites in human urine

The biotransformation of dehydrochloromethyltestosterone (DHCMT, 4-chloro-17β-hydroxy,17α-methylandrosta-1,4-dien-3-one) in man was studied with the aim to discover long-term metabolites valuable for the antidoping analysis. Having applied a high performance liquid chromatography for the fractionation of urinary extract obtained from the pool of several DHCMT positive urines, about 50 metabolites were found. Most of these metabolites were included in the GC-MS/MS screening method, which was subsequently applied to analyze the post-administration and routine doping control samples. As a result of this study, 6 new long-term metabolites were identified tentatively characterized using GC-MS and GC-MS/MS as 4-chloro-17α-methyl-5β-androstan-3α,16,17β-triol (M1), 4-chloro-18-nor-17β-hydroxymethyl,17α-methyl-5β-androsta-1,13-dien-3α-ol (M2), 4-chloro-18-nor-17β-hydroxymethyl,17α-methyl-5β-androst-13-en-3α-ol (M3), its epimer 4-chloro-18-nor-17α-hydroxymethyl,17β-methyl-5β-androst-13-en-3α-ol, 4-chloro-18-nor-17β-hydroxymethyl,17α-methylandrosta-4,13-dien-3α-ol (M4) and its epimer 4-chloro-18-nor-17α-hydroxymethyl,17β-methylandrosta-4,13-dien-3α-ol. The most long-term metabolite M3 was shown to be superior in the majority of cases to the other known DHCMT metabolites, such as 4-chloro-18-nor-17β-hydroxymethyl,17α-methylandrosta-1,4,13-trien-3-one and 4-chloro-3α,6β,17β-trihydroxy-17α-methyl-5β-androst-1-en-16-one.

Development of anabolic-androgenic steroids purity certified reference materials for anti-doping

BACKGROUND

The need for certified reference materials (CRM) of anabolic-androgenic steroids reference materials was emphasized by the Beijing 2008 Olympic game as a tool to improve comparability, ensuring accuracy and traceability of analytical results for competing athletes. The China National Institute of Metrology (NIM) responded to the state request by providing seven anabolic-androgenic steroids (AAS) reference materials for Beijing Olympic anti-doping, GBW (E) 100086-GBW (E) 100092.

EXPERIMENTAL

This work describes the production of the series of AAS CRMs, according to ISO Guides 34 and 35 [1,2], which comprises the material processing, homogeneity and stability assessment, CRMs' characterization including moisture content, trace metal content. The AASs' purity values were assigned with collaborative study involved eight laboratories applying high resolution liquid chromatography-diode array detector (HPLC-DAD). Homogeneity of the AAS CRMs were determined by an in-house validated liquid chromatographic methodology. Potential degradation during storage was also investigated and a shelf-life based on this value was established.

RESULTS

The certified values of CRMs were 99.76±0.079%, 99.76±0.25%, 99.63±0.09%, 99.67±0.11%, 98.82±0.56%, 96.30±0.39% and 99.71±0.49% (purity±expanded uncertainty with confidence level of 95%) for methyltestosterone, testosterone propionate, nandrolone, nandrolone 17-propionate, boldenone, trenbolone acetate and testosterone respectively.

CONCLUSIONS

The certified values for all the studied AAS reference materials are traceable to the international system of units (SI). The CRMs developed were applied by 32 laboratory including sports organizations and analytical laboratories during the 2008 Olympic game for anti-doping control.

Mass spectrometric characterization of urinary metabolites of the selective androgen receptor modulator S-22 to identify potential targets for routine doping controls

Drugs that promote anabolic processes with limited undesirable effects are of considerable therapeutic interest; some notable examples include those for the treatment of cancer cachexia and muscle-wasting diseases. Anabolic properties are not only therapeutically beneficial to critically ill and debilitated patients, but are also desirable to athletes seeking artificial enhancements in endurance, strength and accelerated recovery. The use of anabolic agents in the clinical setting is being reconsidered with the emergence of a new class of drugs referred to as SARMs (selective androgen receptor modulators). SARMs have the potential to complement or even replace anabolic androgenic steroidal use with the benefit of a reduction of the undesirable side effects associated with steroid administration alone. Arylpropionamide-based SARMs such as andarine (S-4) and S-22 have shown promising therapeutic properties and have attracted the interest of elite and amateur athletes despite the absence of clinical approval, and evidence for trafficking and misuse in sport has been obtained by doping control authorities. In this communication, the elucidation of urinary metabolites of the SARM drug candidate S-22 is compared with earlier in vitro metabolism studies. Following oral administration of illicit S-22, urine samples were collected after 62 and 135 h and analyzed for the active drug and its major metabolic products. Liquid chromatography interfaced with high-resolution/high-accuracy (tandem) mass spectrometry was used to identify and/or confirm the predicted target analytes for sports drug testing purposes. S-22 was detected in both specimens accompanied by its glucuronic acid conjugate. This was the B-ring hydroxylated derivative of S-22 plus the corresponding glucuronide (with the phase-II metabolites being the more abundant analytes). In addition, the samples collected 62 h post-administration also contained the phase-I metabolite hydroxylated at the methyl residue (C-20) and the B-ring depleted degradation product ('dephenylated' S-22) together with the corresponding carboxy analog that was previously reported for canine metabolism. The obtained data supports future efforts to effectively screen for and confirm the misuse of the non-approved S-22 drug candidate in doping controls.

Anabolic and androgenic activities of 19-nor-testosterone steroids: QSAR study using quantum and physicochemical molecular descriptors

Quantitative structure-activity relationship (QSAR) study of 19-nor-testosterone steroids family was performed using quantum and physicochemical molecular descriptors. The quantum-chemical descriptors were calculated using semiempirical calculations. The descriptor values were statistically correlated using multi-linear regression analysis. The QSAR study indicated that the electronic properties of these derivatives have significant relationship with observed biological activities. The found QSAR equations explain that the energy difference between the LUMO and HOMO, the total dipole moment, the chemical potential and the value of the net charge of different carbon atoms in the steroid nucleus showed key interaction of these steroids with their anabolic-androgenic receptor binding site. The calculated values predict that the 17α-cyclopropyl-17β, 3β-hydroxy-4-estrene compound presents the highest anabolic-androgenic ratio (AAR) and the 7α-methyl-17β-acetoxy-estr-4-en-3-one compound the lowest AAR. This study might be helpful in the future successful identification of "real" or "virtual" anabolic-androgenic steroids.

European analytical criteria: past, present, and future

In this paper, the past, present, and (possible) future of the European analytical criteria for residues are described. The elaboration of the revision of Commission Decision 9312561EC was a long process starting in 1996 and ending with the formation of a European Commission (EC) working group in 1998. This working group took account of developments in scientific and technical knowledge at that time and produced a draft version of the revision within 6 months. The revision, finally published in 2002 (2002/657/EC), includes new ideas on the identification of analytes and the criteria for performance assessment as well as validation procedures. Currently (2009), the evolution in analytical equipment and progress in scientific research, accompanied by recent European regulatory changes, demands an update or revision of the 2002/657/EC.

Assessing the fate and transformation by-product potential of trenbolone during chlorination

Chlorine disinfection is an effective means for managing microbiological activity during drinking water treatment and can eliminate a number of known organic contaminants. Trenbolone is an androgenic steroidal hormone used primarily as a growth stimulant in the animal feedstock industry and has been found in waterways downstream of such operations. Due to its relatively stable environmental presence, trenbolone may migrate downstream where it can impact drinking water resources. Trenbolone was exposed to hypochlorite under various reaction conditions to determine its stability and the scope of its transformation by-products. The results indicate trenbolone is highly reactive in the presence of hypochlorite and results in an extensive number of transformation by-products. Continued exposure to hypochlorite resulted in a highly dynamic system involving secondary transformations of most of the initial by-products. The results indicate the reactivity of trenbolone is affected by pH and alters the distribution of observed transformation by-products.

High-throughput UHPLC-MS/MS method for the detection, quantification and identification of fifty-five anabolic and androgenic steroids in equine plasma

Anabolic and androgenic steroids (AASs) are synthetic substances related to the primary male sex hormone, testosterone. AASs can be abused in both human and equine sports and, thus, are banned by the International Olympic Committee and the Association of Racing Commissioners International (ARCI). Enforcement of the ban on the use of AASs in racehorses during competition requires a defensible and robust method of analysis. To address this requirement, a high-throughput ultra high-performance liquid chromatography-mass spectrometric (UHPLC-MS) method was developed for the detection, quantification and confirmation of 55 AASs in equine plasma. AASs were recovered from equine plasma samples by liquid-liquid extraction with methyl tert-butyl ether (MTBE). Analytes were chromatographically separated on a sub-2 µm particle size C(18) column with a mobile phase gradient elution and detected by selected-reaction monitoring (SRM) on a triple quadrupole mass spectrometer. AASs with isobaric precursor ions were either chromatographically resolved or mass spectrometrically differentiated by unique precursor-to-product ion transitions. A few of them that could not be resolved by both approaches were differentiated by intensity ratios of three major product ions. All the epimer pairs, testosterone and epitestosterone, boldenone and epiboldenone, nandrolone and epinandrolone, were chromatographically base-line separated. The limit of detection and that of quantification was 50 pg/ml for most of the AASs, and the limit of confirmation was 100-500 pg/ml. Full product ion spectra of AASs at concentrations as low as 100-500 pg/ml in equine plasma were obtained using the triple quadrupole instrument, to provide complementary evidentiary data for confirmation. The method is sensitive and selective for the detection, quantification and confirmation of multiple AASs in a single analysis and will be useful in the fight against doping of racehorses with AASs.

Correlation of product ion profiles with molecular structures of androgenic and anabolic steroids in ESI MS/MS

Androgenic and anabolic steroids (AASs) are a class of chemical substances closely related to testosterone in molecular structure. They can be abused to enhance performances in human and equine athletes, and are banned by the sports authorities. To assist with method development for doping analyses of AASs, investigations were conducted to correlate their product ion profiles with the molecular structures. Although very similar in chemical structure, AASs generated noticeably different product ion profiles from collision-induced dissociation (CID). On the basis of both outlines of the product ion profiles and molecular structures, AASs studied were classified into six subclasses. In each subclass, the product ion profiles were identical or similar. However, the product ion profiles in one subclass were remarkably different from those in another. The classification reveals that the position and number of double bond(s) in conjugation with the 3-carbonyl group in the molecular structure of an AAS have significant effects on product ion profile. The presence or absence of the 19-methyl group in an AAS also has a remarkable influence on its product ion profile. A substitution in the A-, B- or D-ring of an AAS may cause a shift in mass value of the product ions. The correlation of product ion profiles with molecular structures of AASs has the implication that each AAS can be characterized by a combination of its [M + H](+) ion and product ion profile and as a result be identified with specificity. The classified product ion pattern may be useful in the identification of unknown AASs.

Tissue selectivity and potential clinical applications of trenbolone (17beta-hydroxyestra-4,9,11-trien-3-one): A potent anabolic steroid with reduced androgenic and estrogenic activity

Recently, the development of selective androgen receptor modulators (SARMs) has been suggested as a means of combating the deleterious catabolic effects of hypogonadism, especially in skeletal muscle and bone, without inducing the undesirable androgenic effects (e.g., prostate enlargement and polycythemia) associated with testosterone administration. 17beta-Hydroxyestra-4,9,11-trien-3-one (trenbolone; 17beta-TBOH), a synthetic analog of testosterone, may be capable of inducing SARM-like effects as it binds to androgen receptors (ARs) with approximately three times the affinity of testosterone and has been shown to augment skeletal muscle mass and bone growth and reduce adiposity in a variety of mammalian species. In addition to its direct actions through ARs, 17beta-TBOH may also exert anabolic effects by altering the action of endogenous growth factors or inhibiting the action of glucocorticoids. Compared to testosterone, 17beta-TBOH appears to induce less growth in androgen-sensitive organs which highly express the 5alpha reductase enzyme (e.g., prostate tissue and accessory sex organs). The reduced androgenic effects result from the fact that 17beta-TBOH is metabolized to less potent androgens in vivo; while testosterone undergoes tissue-specific biotransformation to more potent steroids, dihydrotestosterone and 17beta-estradiol, via the 5alpha-reductase and aromatase enzymes, respectively. Thus the metabolism of 17beta-TBOH provides a basis for future research evaluating its safety and efficacy as a means of combating muscle and bone wasting conditions, obesity, and/or androgen insensitivity syndromes in humans, similar to that of other SARMs which are currently in development.

The application of in vitro technologies to study the metabolism of the androgenic/anabolic steroid stanozolol in the equine

In this study, the use of equine liver/lung microsomes and S9 tissue fractions were used to study the metabolism of the androgenic/anabolic steroid stanozolol as an example of the potential of in vitro technologies in sports drug surveillance. In vitro incubates were analysed qualitatively alongside urine samples originating from in vivo stanozolol administrations using LC-MS on a high-resolution accurate mass Thermo Orbitrap Discovery instrument, by LC-MS/MS on an Applied Biosystems Sciex 5500 Q Trap and by GC-MS/MS on an Agilent 7000A. Using high-resolution accurate mass full scan analysis on the Orbitrap, equine liver microsome and S9 in vitro fractions were found to generate all the major phase-1 metabolites observed following in vivo administrations. Additionally, analysis of the liver microsomal incubates using a shallower HPLC gradient combined with various MS/MS functions on the 5500 Q trap allowed the identification of a number of phase 1 metabolites previously unreported in the equine or any other species. Comparison between liver and lung S9 metabolism showed that the liver was the major site of metabolic activity in the equine. Furthermore, using chemical enzyme inhibitors that are known to be selective for particular isoforms in other species suggested that an enzyme related to CYP2C8 may be responsible the production of 16-hydroxy-stanozolol metabolites in the equine. In summary, the in vitro and in vivo phase 1 metabolism results reported herein compare well and demonstrate the potential of in vitro studies to compliment the existing in vivo paradigm and to benefit animal welfare through a reduction and refinement of animal experimentation.

Criteria to distinguish between natural situations and illegal use of boldenone, boldenone esters and boldione in cattle 2. Direct measurement of 17beta-boldenone sulpho-conjugate in calf urine by liquid chromatography--high resolution and tandem mass spectrometry

Boldenone is banned in the European Union (Directive 96/22/EC) as growth promoter for meat producing animals. Boldione (ADD), boldenone and boldenone esters (mainly the undecylenate form) are commercially available as anabolic preparations, either to the destination of human, horse or cattle. Since the late 90s, the natural occurrence of boldenone metabolites has been reported in cattle. According to EU regulation, the unambiguous demonstration of boldenone administration in bovine urine should be provided on the basis of boldenone identification in the corresponding conjugate fraction. An analytical method has been developed and validated according to current standards with main concern to the measurement of intact 17beta-boldenone-sulphate. The analytical procedure included direct extraction-purification of target analyte on octadecylsilyl cartridges and direct detection of phase II metabolite by liquid chromatography (negative electrospray), tandem mass spectrometry (QqQ) or high resolution mass spectrometry (Orbitrap). Decision limit (CCalpha) and detection capability (CCbeta) were respectively 0.2 microg L(-1) and 0.4 microg L(-1) on triple quadrupole and 0.1 microg L(-1) and 0.2 microg L(-1) on hybrid system. The method was successfully applied to the analysis of incurred samples collected in different experiments. 17beta-Boldenone-sulphate was measurable up to 36h after oral administration of boldione, and 30 days after 17beta-boldenone undecylenate intra-muscular injection. This conjugate form was never detected in non-treated animals, confirming its status of definitive candidate marker for boldenone administration in calf.

Detection and structural investigation of metabolites of stanozolol in human urine by liquid chromatography tandem mass spectrometry

The applicability of LC-MS/MS in precursor ion scan mode for the detection of urinary stanozolol metabolites has been studied. The product ion at m/z 81 has been selected as specific for stanozolol metabolites without a modification in A- or N-rings and the product ions at m/z 97 and 145 for the metabolites hydroxylated in the N-ring and 4-hydroxy-stanozolol metabolites, respectively. Under these conditions, the parent drug and up to 15 metabolites were found in a positive doping test sample. The study of a sample from a chimeric uPA-SCID mouse collected after the administration of stanozolol revealed the presence of 4 additional metabolites. The information obtained from the product ion spectra was used to develop a SRM method for the detection of 19 compounds. This SRM method was applied to several doping positive samples. All the metabolites were detected in both the uPA-SCID mouse sample and positive human samples and were not detected in none of the blank samples tested; confirming the metabolic nature of all the detected compounds. In addition, the application of the SRM method to a single human excretion study revealed that one of the metabolites (4xi,16xi-dihydroxy-stanozolol) could be detected in negative ionization mode for a longer period than those commonly used in the screening for stanozolol misuse (3'-hydroxy-stanozolol, 16beta-hydroxy-stanozolol and 4beta-hydroxy-stanozolol) in doping analysis. The application of the developed approach to several positive doping samples confirmed the usefulness of this metabolite for the screening of stanozolol misuse. Finally, a tentative structure for each detected metabolite has been proposed based on the product ion spectra measured with accurate masses using UPLC-QTOF MS.

In vivo MRI evaluation of anabolic steroid precursor growth effects in a guinea pig model

Anabolic steroids are widely used to increase skeletal muscle (SM) mass and improve physical performance. Some dietary supplements also include potent steroid precursors or active steroid analogs such as nandrolone. Our previous study reported the anabolic steroid effects on SM in a castrated guinea pig model with SM measured using a highly quantitative magnetic resonance imaging (MRI) protocol. The aim of the current study was to apply this animal model and in vivo MRI protocol to evaluate the growth effects of four widely used over-the-counter testosterone and nandrolone precursors: 4-androstene-3 17-dione (androstenedione), 4-androstene-3beta 17beta-diol (4-androsdiol), 19-nor-4-androstene-3beta-17beta-diol (bolandiol) and 19-nor-4-androstene-3 17-dione (19-norandrostenedione). The results showed that providing precursor to castrated male guinea pigs led to plasma steroid levels sufficient to maintain normal SM growth. The anabolic growth effects of these specific precursors on individual and total muscle volumes, sexual organs, and total adipose tissue over a 10-week treatment period, in comparison with those in the respective positive control testosterone and nandrolone groups, were documented quantitatively by MRI.

Synthesis and anabolic/androgenic evaluation of novel 9alpha-fluorosteroids

3Beta,11beta-dihydroxy-9alpha-fluor-5alpha-androstane-17-one (2), 3beta-acetoxy-9alpha-fluor-11beta-hydroxy-5alpha-androstane-17-one (3), 3beta-acetoxy-9alpha-fluor-11beta,17beta-dihydroxy-5alpha-androstane (4), 3beta,17beta-diacetoxy-9alpha-fluor-11beta-hydroxy-5alpha-androstane (5), 3beta-acetoxy-9alpha-fluor-11beta-hydroxy-5alpha-androstane 17beta-propionate (6), 3beta-acetoxy-9alpha-fluor-11beta-hydroxy-5alpha-androstane 17beta-enanthate (7), 3beta-acetoxy-9alpha-fluor-11beta-hydroxy-5alpha-androstane 17beta-isobutyrate (8) were synthesized in the present study. Compounds 2 and 8 exhibited higher anabolic activity than the rest of the synthesized compounds. The structure of all these newly synthesized compounds was confirmed by analytic spectral data (mass, (1)H NMR and (13)C NMR).

Ultra-performance liquid chromatography/tandem mass spectrometry in high-throughput detection, quantification and confirmation of anabolic steroids in equine plasma

An ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) method for fast-throughput analysis of eight anabolic and androgenic steroids (AAS) in equine plasma is reported. Analytes were recovered by liquid-liquid extraction using methyl tert-butyl ether, separated on a 1.9 microm C(18) reversed-phase column, and analyzed in positive electrospray ionization mode on a triple quadrupole mass spectrometer with selected reaction monitoring (SRM) and full product ion scans. Two SRM ion transitions were monitored for each AAS during screening to obtain highly selective screening results. Full product ion spectra of excellent quality for AAS, at 100 pg/0.5 mL in plasma, devoid of interfering spectra from impurities in plasma, were obtained. To our knowledge, this is the first report on the acquisition of full product ion spectra at such a low analyte concentration and plasma volume using a triple quadrupole instrument. In addition to product ion intensity ratios obtained from three SRM scans for identifying AAS in equine plasma, full product ion spectra were used as supporting evidence for confirmation. For quantification, deuterium-labeled testosterone and stanozolol were used as internal standards (ISs). The limits of detection, quantification and confirmation were 6.25-12.5 pg/0.5 mL, 25 pg/0.5 mL and 50-100 pg/0.5 mL, respectively. There was no significant matrix effect on the analysis of all eight AAS. Intra-day precision and accuracy were 2-15% and 91-107%, respectively. Inter-day precision and accuracy were 1-21% and 94-110%, respectively. Total analysis time was 5 min. To date, the method has been successfully used in the analysis of >12,000 samples for AAS in plasma samples from racehorses competing in the State of Pennsylvania. The method is fast, selective, reproducible, and reliable.

Autophagy and the functional roles of Atg5 and beclin-1 in the anti-tumor effects of 3beta androstene 17alpha diol neuro-steroid on malignant glioma cells

In this study, we demonstrate that the anti-tumor activity of the neuro-steroid, 3beta androstene 17alpha diol (17alpha-AED) on malignant glioma cells is mediated by the induction of autophagy. 17alpha-AED can inhibit the proliferation an induce cell death of multiple, unrelated gliomas with an IC(50) between 8 and 25muM. 17alpha-AED treatment induced the formation of autophagosomes and acidic vesicular organelles in human malignant gliomas which was blocked by bafilomycin A1 or 3-methyladenine. Cleavage of microtubule-associated protein-light chain 3 (LC3), an essential step in autophagosome formation, was detected in human malignant glioma cells exposed to 17alpha-AED. In 17alpha-AED treated T98G glioma cells there was an increase in the autophagy related proteins Atg5 and beclin-1. Silencing of ATG5 or beclin-1 with small interfering RNA significantly reduced the incidence of autophagy in 17alpha-AED treated malignant gliomas and attenuated the cytotoxic effects of the neuro-steroid indicating that the induction of autophagy mediates the anti-glioma activity of 17alpha-AED rather than serving as a cyto-protective response. These results demonstrate that 17alpha-AED possesses significant anti-glioma activity when used at pharmacologically relevant concentrations in vitro and the cytotoxic effects are resultant from the induction of autophagy.

Comparative study of matrices for their use in the rapid screening of anabolic steroids by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry

New data on sample preparation and matrix selection for the fast screening of androgenic anabolic steroids (AAS) by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) is presented. The rapid screening of 15 steroids included in the World Anti-Doping Agency (WADA) prohibited list using MALDI was evaluated. Nine organic and two inorganic matrices were assessed in order to determine the best matrix for steroid identification in terms of ionisation yield and interference by characteristic matrix ions. The best results were achieved for the organic matrices 2-(4-hydroxyphenylazo)benzoic acid (HABA) and trans-3-indoleacrylic acid (IAA). Good signals for all the steroids studied were obtained for concentrations as low as 0.010 and 0.050 microg/mL on the MALDI sample plate for the HABA and IAA matrices, respectively. For these two matrices, the sensitivity achieved by MALDI is comparable with the sensitivity achieved by gas chromatography/mass spectrometry (GC/MS), which is the conventional technique used for AAS detection. Furthermore, the accuracy and precision obtained with MALDI are very good, since an internal mass calibration is performed with the matrix ions. For the inorganic matrices, laser fluences higher than those used with organic matrices are required to obtain good MALDI signals. When inorganic matrices were used in combination with glycerol as a dispersing agent, an important reduction of the background noise was observed. Urine samples spiked with the study compounds were processed by solid-phase extraction (SPE) and the screening was consistently positive.

Identification of drostanolone and 17-methyldrostanolone metabolites produced by cryopreserved human hepatocytes

Methyldrostanolone (2alpha,17alpha-dimethyl-17beta-hydroxy-5alpha-androstan-3-one) was synthesized from drostanolone (17beta-hydroxy-2alpha-methyl-5alpha-androstan-3-one) and identified in commercial products. Cultures of cryopreserved human hepatocytes were used to study the biotransformation of drostanolone and its 17-methylated derivative. For both steroids, the common 3alpha- (major) and 3beta-reduced metabolites were identified by GC-MS analysis of the extracted culture medium and the stereochemistry confirmed by incubation with 3alpha-hydroxysteroid dehydrogenase. Structures corresponding to hydroxylated metabolites in C-12 (minor) and C-16 were proposed for other metabolites based upon the evaluation of the mass spectra of the pertrimethylsilyl (TMS-d(0) and TMS-d(9)) derivatives. Finally, on the basis of the GC-MS and (1)H NMR data and through chemical synthesis of the 17-methylated model compounds, structures could be proposed for metabolites hydroxylated in C-2. All the metabolites extracted from hepatocyte culture medium were present although in different relative amounts in urines collected following the administration to a human volunteer, therefore confirming the suitability of the cryopreserved hepatocytes to generate characteristic metabolites and study biotransformation of new steroids.

Steroid analysis and doping control 1960-1980: scientific developments and personal anecdotes

Definitive proof of anabolic steroid abuse in sports was not possible prior to the introduction of combined gas chromatography/mass spectrometry (GC/MS).This is a report of the early history (1960-1980) of GC/MS and radioimmunoassay, and how these techniques were utilized in the first years of steroid doping control in athletics. There were several key individuals and research groups involved in the early technical developments, and their essential contributions have been acknowledged. Our laboratory was the first IAAF (International Association of Athletic Federations) sanctioned site to do steroid GC/MS steroid analysis resulting in athletes being disqualified from competition. We had notable successes, including the only East German female competitor ever suspended during the tenure of the DDR (Deutsche Demokratische Republik). This paper not only covers scientific advances and milestones in the incorporation of steroid testing into international athletics, but also includes personal anecdotes of these early years before doping control became justifiably regimented. By the early 1980s, in anticipation of the Los Angeles Olympic games, dedicated year-round sports testing facilities had been established and part-time amateurs could step aside.