Development and application of analytical procedures for the GC-MS/MS analysis of the sulfates metabolites of anabolic androgenic steroids: The pivotal role of chemical hydrolysis.

In this work, we present a gas-chromatography tandem mass spectrometry (GC-MS/MS) method for the identification of the sulfo-conjugate metabolites of pseudo-endogenous steroids (endogenous steroids when administered exogenously). We have preliminarily evaluated the performances of different preparations of sulfatases from Pseudomonas aeruginosa and Helix pomatia, characterized by various origins and catalytic activities, and compared the efficacy of the enzymatic hydrolysis with chemical hydrolysis, performed with a mixture of ethyl acetate, methanol, and sulphuric acid. A procedure for the selective isolation of steroid conjugates from the urine matrix has been designed and optimized, based on the "sequential" extraction of the glucuro-conjugated and of the sulfo-conjugated fractions, performed by two different direct methods, i.e. by ion paired extraction or solid-phase extraction. More specifically, the former method is based on the use of N,N-dimethylephedrinium bromide as the ion paired extraction reagent, while the latter on the use of WAX® (weak anion exchange) cartridges. The performance of the newly developed procedure has been assessed by the analysis of real urine excretion samples collected after the oral intake of a single dose of dehydroepiandrosterone (DHEA) or androstenedione (AED), measuring the concentration of epiandrosterone (EpiA) sulfate. Our results have shown the following: (i) although the yields of chemical hydrolysis and enzymatic hydrolysis are in some cases quite similar, the former is generally preferable since it results in the quantitative cleavage of sulfate moiety; (ii) ion paired extraction has been selected as the most reliable method for direct isolation of sulfate steroids from urine matrices; (iii) EpiA sulfate allows to prolong the detectability of DHEA and AED when compared to routinely used steroidal target compounds.

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.

Consumption of a Specially-Formulated Mixture of Essential Amino Acids Promotes Gain in Whole-Body Protein to a Greater Extent than a Complete Meal Replacement in Older Women with Heart Failure.

Heart failure in older individuals is normally associated with a high body mass index and relatively low lean body mass due to, in part, a resistance to the normal anabolic effect of dietary protein. In this study we have investigated the hypothesis that consumption of a specially-formulated composition of essential amino acids (HiEAAs) can overcome anabolic resistance in individuals with heart failure and stimulate the net gain of body protein to a greater extent than a commercially popular protein-based meal replacement beverage with greater caloric but lower essential amino acid (EAA) content (LoEAA). A randomized cross-over design was used. Protein kinetics were determined using primed continuous infusions of L-(2H5)phenylalanine and L-(2H2)tyrosine in the basal state and for four hours following consumption of either beverage. Both beverages induced positive net protein balance (i.e., anabolic response). However, the anabolic response was more than two times greater with the HiEAA than the LoEAA (p < 0.001), largely through a greater suppression of protein breakdown (p < 0.001). Net protein accretion (g) was also greater in the HiEAA when data were normalized for either amino acid or caloric content (p < 0.001). We conclude that a properly formulated EAA mixture can elicit a greater anabolic response in individuals with heart failure than a protein-based meal replacement. Since heart failure is often associated with obesity, the minimal caloric value of the HiEAA formulation is advantageous.

Futility of current urine salbutamol doping control.

AIMS: Salbutamol is used in the management of obstructive bronchospasm, including that of some elite athletes. It is claimed that high salbutamol (oral) doses may also have an anabolic effect. Therefore, inhalation of salbutamol is restricted by the World Anti-Doping Agency (WADA) to a maximal daily dose. Urine is tested for violations, but recent cases have resulted in a debate regarding the validity of this approach. It was our aim to determine whether current approaches are sufficiently able to differentiate approved usage from violations. METHODS: We extracted pharmacokinetic parameters from literature for salbutamol and its sulphated metabolite. From these parameters, a semi-physiological pharmacokinetic model of inhaled and orally administered salbutamol was synthesized, validated against literature data, and used to perform clinical trial simulations (n = 1000) of possible urine concentrations over time resulting from WADA-allowed and oral unacceptable dosages. RESULTS: The synthesized model was able to predict the literature data well. Simulations showed a very large range of salbutamol concentrations, with a significant portion of virtual subjects (15.4%) exceeding the WADA threshold limit of 1000 ng ml-1 at 1 h post-dose. CONCLUSIONS: The observed large variability in urine concentrations indicates that determining the administered dose from a single untimed urine sample is not feasible. The current threshold inadvertently leads to incorrect assumptions of violation, whereas many violations will go unnoticed, especially when samples are taken long after drug administration. These issues, combined with the dubious assertion of its anabolic effect, leads us to conclude that the large effort involved in testing should be reconsidered.

Determination of Salbutamol Residues in Goat Various Tissues After Exposure to Growth-promoting Doses.

In order to monitor salbutamol (SAL) use in goats as a repartitioning, we determined SAL residues in various tissues of goats after repeated oral SAL administration at a dose of 0.15 mg/kg daily for 21 days. SAL concentrations were measured by ultra performance liquid chromatography tandem mass spectrometry in extracts of tissues from goats sacrificed 0.25, 1, 3, 7, 14, 21 and 28 days after the last dose. Our results showed that on Day 0.25 of the withdrawal period, the residual proportions of SAL (expressed as percentage) in liver, kidney, lung, hair, stomachs and muscle were 19.5%, 15.3%, 3.3%, 9.6%, 28.2% and 0.8%, respectively. As the withdrawal time increased, the SAL concentrations in most tissues (except hair) decreased rapidly over the first 3 days and more slowly in the following 25 days. After a 28-day withdrawal period, hair, lung, muscle, liver, fat, eyes, rumen, kidney and abomasum still contained ~32.3%, 15.3%, 7.1%, 6.5%, 5.6%, 1.5%, 0.8% and 0.5% compared to the initial residual concentrations determined on Day 0.25, respectively. On withdrawal Day 28, the highest concentrations of SAL were found in hair (16.58 ± 9.48 µg/kg), followed by liver (7.01 ± 0.94 µg/kg), lung (2.81 ± 1.23 µg/kg), kidney (0.64 ± 0.56 µg/kg), whereas the concentrations in other tissues were lower than limit of quantification (0.50 µg/kg). SAL residues were not detected in bile, plasma and brain on Days 7, 7 and 3 after discontinuation of dosing. These findings indicated that the distribution and depletion rates of SAL differed between tissues. It should be noted that SAL residues in stomach were higher than those in muscles during the early withdrawal. We conclude that hair is the preferred tissue to monitor the administration of SAL to living goats, whereas liver can be used to monitor SAL in the carcass for determination of compliance with food safety regulation.

Structure-Based Approach To Identify 5-[4-Hydroxyphenyl]pyrrole-2-carbonitrile Derivatives as Potent and Tissue Selective Androgen Receptor Modulators.

In an effort to find new and safer treatments for osteoporosis and frailty, we describe a novel series of selective androgen receptor modulators (SARMs). Using a structure-based approach, we identified compound 7, a potent AR (ARE EC50 = 0.34 nM) and selective (N/C interaction EC50 = 1206 nM) modulator. In vivo data, an AR LBD X-ray structure of 7, and further insights from modeling studies of ligand receptor interactions are also presented.

Short communication: Muscle protein synthetic response to microparticulated whey protein in middle-aged men.

Whey protein concentrate (WPC) is a high-quality dairy ingredient that is often included in formulated food products designed to stimulate muscle anabolism. Whey protein concentrate can be affected by UHT processing, and its sensory properties are not compatible with some formulated food products. Microparticulated WPC (mWPC) is a novel ingredient that is resistant to heat treatment and has enhanced sensory properties. When 16 healthy middle-aged men consumed 20 g of either WPC or mWPC, both proteins increased plasma essential AA and leucine concentrations with no detectable difference in curve kinetics. Myofibrillar protein synthesis was increased in both groups for 90 min after ingestion with no difference between groups. Ingestion of mWPC resulted in a muscle anabolic response that was equivalent to that of WPC over the full 210-min measurement period. Formulated products incorporating mWPC or standard WPC would provoke equivalent anabolic responses.

Safety, pharmacokinetics and pharmacological effects of the selective androgen receptor modulator, GSK2881078, in healthy men and postmenopausal women.

AIM: Selective androgen receptor modulators (SARMs) induce anabolic effects on muscle without the adverse effects of androgenic steroids. In this first-in-human study, we report the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics of the SARM GSK2881078. METHODS: In Part A, healthy young men (n = 10) received a single dose of study drug (0 mg, 0.05 mg, 0.1 mg, 0.2 mg GSK2881078 or matching-placebo). In Part B, repeat-dose cohorts in men (n = 65) were 0.05 mg, 0.2 mg then 0.08 mg, 0.24 mg, 0.48 mg, 0.75 mg, or placebo; in women (n = 24) they were 0.24 mg, 0.35 mg, or placebo (7 days for 0.5 mg, 14 days for other doses). RESULTS: PK analysis showed dose-proportional increases in exposure and a long >100-h half-life. No significant effects on vital signs, electrocardiograms, cardiac telemetry or standard clinical laboratory studies were observed. A dose-response effect was observed on lowering both high-density lipoprotein and sex hormone-binding globulin. In females at 0.35 mg, differences from placebo were -0.518 (95% confidence interval: -0.703, -0.334) mmol l-1 and -39.1 (-48.5, -29.7) nmol l-1 , respectively. Women showed greater sensitivity to these parameters at lower doses than men. Drug-related adverse events (AEs) were mild. One woman developed a drug rash and was withdrawn. Two men had elevated creatine phosphokinase after physical exertion during follow-up. A serious AE occurred in a subject on placebo. CONCLUSIONS: These data demonstrate pharmacodynamic effects with acceptable tolerability and support further clinical evaluation of this SARM.

Synthesis and biological evaluation of novel selective androgen receptor modulators (SARMs). Part II: Optimization of 4-(pyrrolidin-1-yl)benzonitrile derivatives.

We recently reported a class of novel tissue-selective androgen receptor modulators (SARMs), represented by a naphthalene derivative A. However, their pharmacokinetic (PK) profiles were poor due to low metabolic stability. To improve the PK profiles, we modified the hydroxypyrrolidine and benzonitrile substituents of 4-(pyrrolidin-1-yl)benzonitrile derivative B, which had a comparable potency as that of compound A. This optimization led us to further modifications, which improved metabolic stability while maintaining potent androgen agonistic activity. Among the synthesized compounds, (2S,3S)-2,3-dimethyl-3-hydroxylpyrrolidine derivative 1c exhibited a suitable PK profile and improved metabolic stability. Compound 1c demonstrated significant efficacy in levator ani muscle without increasing the weight of the prostate in an in vivo study. In addition, compound 1c showed agonistic activity in the CNS, which was detected using sexual behavior induction assay.

Revealing the influence of glucocorticoid treatment on the excretion of anabolic-androgenic steroids in horses through in vitro digestive simulations and an in vivo case study.

Anabolic-androgenic steroids (AAS) are strictly forbidden in equine sports because of their stimulating effect on muscle growth and performance. Nevertheless, low levels of AAS have been found in some horses, untreated with AAS. Glucocorticoids (GC), used as an anti-inflammatory therapy and structurally related to AAS, might play a role in this phenomenon. In order to unravel this possible correlation the influence of glucocorticoid treatment on the excretion of AAS was studied both in vivo and in vitro. In vivo effects were investigated by analysing urine samples collected from a gelding treated with betamethasone. Additionally, multiple in vitro digestion simulations were set up, according to a previously validated protocol, to study the possibility of a direct biotransformation of glucocorticoids to AAS, by the microbiota of the equine hindgut. Urine and in vitro digestion samples were extracted and analysed with UHPLC-MS/MS and UHPLC-Orbitrap-HRMS analytical methods. A significant influence on the urinary excretion of α-testosterone (αT), ß-testosterone (ßT) and androsta-1,4-diene-3,17-dione (ADD) was seen. αT-concentrations up to 20ng/mL were detected. ADD was not found before treatment but could be detected post-treatment. Cortisone and cortisol also peaked (>30ng/mL) between day 37 and 48 post-treatment. The in vitro digestion results however revealed no direct biotransformation of glucocorticoids to AAS by the microbiota of the equine hindgut. This study shows that a glucocorticoid treatment can disrupt the synthesis and excretion of AAS, not by direct biotransformation upon gastrointestinal digestion, but more likely by influencing the hypothalamic-pituitary-adrenal axis.

Rapid uptake, biotransformation, esterification and lack of depuration of testosterone and its metabolites by the common mussel, Mytilus spp.

The presence of the vertebrate steroids, testosterone (T) and 17ß-estradiol in mollusks is often cited as evidence that they are involved in the control of their reproduction. In this paper, we show that a likely source of T in at least one species, the common mussel (Mytilus spp.), is from uptake from water. When mussels were exposed to waterborne tritiated T ([3H]-T) in a closed container, the radioactivity decreased rapidly and exponentially until, by 24h, approximately 35% remained in the water. The rate of uptake of radiolabel could not be saturated by concentrations as high as 16.5µgL-1 (mean measured) of non-radiolabeled T, showing that the animals have a very high capacity for uptake of T. At least 30% of the applied radioactivity could be extracted from the tissues of the animals with organic solvents and most of this (26% of the total applied radioactivity) was in the fatty acid ester fraction. Following alkaline hydrolysis, reverse phase HPLC and TLC, this fraction was shown to consist predominantly of 5α-dihydrotestosterone and 5α-androstane-3ß,17ß-diol, while T was a minor component. These steroids were definitively identified in the fatty acid ester fraction by mass spectrometry. Overall, less than 5% of the [3H]-T applied to the system remained untransformed at the end of exposure. After ten days of depuration there was no reduction in the total amount of radioactivity in the tissues, nor any changes in the ratio of the metabolites in the ester fraction. These findings show that any association between T presence and reproductive status or sex is confounded by their significant capacity for uptake, and that T undergoes extensive metabolism in mussels in vivo and therefore may not be representative of the androgenic burden of the animals. Consequently, measurements of T in mussel tissue offer little utility as an indicator of reproductive status or sex.

Analytical strategies to detect enobosarm administration in bovines.

Selective androgen receptor modulators (SARMs) are a novel class of androgen receptor ligands. They are intended to exhibit the same kind of effects as androgenic drugs, like anabolic steroids, but be much more selective in their action, targeting particular tissues without any undesirable effects on others. While the main applications of these synthetic substances are for therapeutic purposes, they also have a high potential for misuse in veterinary practice and the sporting world. In order to guarantee for consumers with food from animal origin that it is free from any residues of such compounds, analytical strategies are required to ensure safe food and also to enable fair trade between producers. In this context an animal experiment involving bovines administered with enobosarm was conducted to provide the study with biological matrices. Different animal matrices (urine and faeces) were investigated to select the most appropriate matrix for use for control purposes, in terms of metabolite relevance and detection time window. Based on ultra-high-pressure liquid chromatography (UHPLC) with tandem mass spectrometry (LC-MS/MS) this work highlighted the presence of sulfonated and glucuronated-conjugated forms of the molecule in the urine of treated animals. Enobosarm could be detected in urine up to 9 days after the administration when samples underwent phase II hydrolysis. Faeces was demonstrated to be the main matrix of excretion of enobosarm since values up to 500 times higher compared with urine could be detected for 21 days. There was no difference between the kinetic profiles when a deconjugation step was or was not was applied.

Where does hydrolysis of nandrolone decanoate occur in the human body after release from an oil depot?

Long-term therapy of nandrolone (N) is recommended to increase mineral density and muscle strength. Using a parenteral sustained release drug formulation with nandrolone decanoate (ND), therapeutic N levels can be achieved and maintained. Until now, it is unknown if hydrolysis of ND into N occurs in tissue at the injection site or after systemic absorption. Therefore, hydrolysis studies were conducted to investigate the location and rate of ND hydrolysis after its release from the oil depot. ND hydrolysis was studied in porcine tissues, to mimic the human muscular and subcutaneous tissues. Additionally, the ND hydrolysis was studied in human whole blood, plasma and serum at a concentration range of 23.3-233.3µM. ND hydrolysis only occurred in human whole blood. The hydrolysis did not start immediately, but after a lag time. The mean lag time for all studied concentrations was 34.9±2.5min. Because of a slow penetration into tissue, hydrolysis of ND is found to be very low in surrounding tissue. Therefore the local generation of the active compound is clinically irrelevant. It is argued that after injection of the oil depot, ND molecules will be transported via the lymphatic system towards lymph nodes. From here, it will enter the central circulation and within half an hour it will hydrolyse to the active N compound.

[Relationship of pharmacokinetics, changes of bone turnover markers and BMD/fractures efficacy during treatment with anabolic agents;Teriparatide daily and once weekly subcutaneous injections.]

Teriparatide(recombinant human PTH1-34, 20 µg daily subcutaneous injection)has been approved for osteoporosis patients at high risk of fracture in many countries including Japan. Teriparatide daily injection therapy has been reported to increase BMD, improve microarchitecture of bone, and reduce the risk of new vertebral fractures and that of non-vertebral fractures. Pharmakokinetic(PK)study after a single Teriparatide injection of the daily dose in healthy Japanese postmenopausal women(n=18)revealed very rapid achievement of peak blood level(median of tmax=0.25 hr)followed by fast disappearance from the blood(mean t1/2=0.708 hr, n=17). Consistent with these PK characteristics, a rapid increase in bone formation marker and later increase in bone resorption marker has previously been observed, which was described as a bone anabolic window. More recently, once weekly subcutaneous injection of teriparatide acetate(56.5 µg)has been reported to reduce the risk of new vertebral fractures compared with placebo and has been approved in Japan. PK study after injection of the higher weekly dose in healthy Japanese postmenopausal women(n=10)revealed a relatively slow achievement of the peak blood level(mean tmax=0.875 hr)compared to daily injections, followed by relatively slow disappearance from the blood(mean t1/2=1.295 hr). Consistent with these PK characteristics, an initial(<24 hr)transient decrease of bone formation markers(serum osteocalcin and P1NP)and transient increase of bone resorption markers(serum NTX and urinary CTX)were observed. However, afterword, the bone formation and resorption markers were increased and decreased, respectively, for longer than 1 week from the baseline levels. The relationship of pharmacokinetics, changes of bone turnover markers and BMD/fractures efficacy during daily versus weekly teriparatide treatment needs to be clarified.

In vivo and in vitro metabolism of the designer anabolic steroid furazadrol in thoroughbred racehorses.

Furazadrol ([1',2']isoxazolo[4',5':2,3]-5α-androstan-17ß-ol) is a designer anabolic androgenic steroid that is readily available via the internet. It contains an isoxazole fused to the steroid A-ring which offers metabolic stability and noteworthy anabolic activity raising concerns over the potential for abuse of this compound in equine sports. The metabolism of furazadrol was studied by in vivo and in vitro methods for the first time. Urinary furazadrol 17-sulfate and furazadrol 17-glucuronide metabolites were detected in vivo after a controlled administration and compared with synthetically-derived reference materials in order to confirm their identities. They were quantified to establish the excretion profile and a suitable limit of detection. Minor metabolites were also detected, including epifurazadrol, hydroxylated furazadrol, and hydroxylated and oxidised furazadrol, present as the sulfate and glucuronide conjugates. Phase II metabolites were subjected to enzymatic hydrolysis by Escherichia coli ß-glucuronidase and Pseudomonas aeruginosa arylsulfatase to further confirm the identity of the corresponding phase I metabolites. The metabolism profile was compared to the products obtained from an in vitro phase I metabolism study, with all but two of the minor in vivo phase I metabolites observed in the in vitro system. These investigations identify the key urinary metabolites of furazadrol following oral administration, which can be incorporated into anti-doping screening and confirmation procedures.

Metabolic studies of prostanozol with the uPA-SCID chimeric mouse model and human liver microsomes.

Anabolic androgenic steroids are prohibited by the World Anti-Doping Agency because of their adverse health and performance enhancing effects. Effective control of their misuse by detection in urine requires knowledge about their metabolism. In case of designer steroids, ethical objections limit the use of human volunteers to perform excretion studies. Therefore the suitability of alternative models needs to be investigated. In this study pooled human liver microsomes (HLM) and an uPA(+/+)-SCID chimeric mouse model were used to examine the metabolism of the designer steroid prostanozol as a reference standard. Metabolites were detected by GC-MS (full scan) and LC-MS/MS (precursor ion scan). In total twenty-four prostanozol metabolites were detected with the in vitro and in vivo metabolism studies, which could be grouped into two broad classes, those with a 17-hydroxy- and those with a 17-keto-substituent. Major first phase metabolic sites were tentatively identified as C-3'; C-4 and C-16. Moreover, 3'- and 16ß-hydroxy-17-ketoprostanozol could be unequivocally identified, since authentic reference material was available, in both models. Comparison with published data from humans showed a good correlation, except for phase II metabolism. As metabolites were in contrast to the human studies predominantly present in the free fraction. Two types of metabolites ((di)hydroxylated prostanozol metabolites) that have not been described before could be confirmed in a real positive doping control sample. Hence, the results provide further evidence for the applicability of chimeric mice and HLM to perform metabolism studies of designer steroids.

Metabolism study of boldenone in human urine by gas chromatography-tandem mass spectrometry.

Boldenone (BOLD), an anabolic steroid, is likely to be abused in livestock breeding and in sports. Although some of BOLD metabolites in human urine, such as 5ß-adrost-1-en-17ß-ol-3-one (BM1), have been detected, investigations on their excretion patterns for both genders are insufficient. Moreover, little research on 17α-BOLD glucuronide as a metabolite in human urine has been reported. The aim of this study is to make a contribution to the knowledge of 17ß-BOLD metabolism in humans. Three male and three female volunteers were orally administrated with 30mg 17ß-BOLD. Urine samples were collected and analyzed with gas chromatography-tandem mass spectrometry. The data proved that 17ß-BOLD, BM1, and 17α-BOLD were excreted in urine in both free and glucuronic conjugated forms after administration of 17ß-BOLD. For most subjects, the urinary concentrations of BM1 were higher than that of 17ß-BOLD. 17α-BOLD was excreted in small amounts. 17α-BOLD, 17ß-BOLD, and BM1 were present naturally in urine with low concentrations. Administration of 30mg 17ß-BOLD could not influence the excretion profiles of urinary androsterone, etiocholanolone, and testosterone/epitestosterone ratio. There were no differences in BOLD metabolic patterns between man and woman.

Correction of Hormonal and Metabolic Disorders in Male Rats with Developing Experimental Diabetes.

Synthetic radioinert androgen methyltrienolone administered daily for 2 weeks to male rats with severe diabetes led to a sharp increase in blood testosterone and was accompanied by reduction in glucose level due to an increase in tissue sensitivity to insulin. Normalization of plasma testosterone concentration contributed to saturation of active androgen receptors in the myocardium with testosterone; the number of free receptors decreased by 1.8 times. Testosterone that diminishes the catabolic effects of glucocorticoids improved the state of the myocardium, which was confirmed by activation of DNA and RNA synthesis.

Annual banned-substance review: analytical approaches in human sports drug testing.

Within the mosaic display of international anti-doping efforts, analytical strategies based on up-to-date instrumentation as well as most recent information about physiology, pharmacology, metabolism, etc., of prohibited substances and methods of doping are indispensable. The continuous emergence of new chemical entities and the identification of arguably beneficial effects of established or even obsolete drugs on endurance, strength, and regeneration, necessitate frequent and adequate adaptations of sports drug testing procedures. These largely rely on exploiting new technologies, extending the substance coverage of existing test protocols, and generating new insights into metabolism, distribution, and elimination of compounds prohibited by the World Anti-Doping Agency (WADA). In reference of the content of the 2014 Prohibited List, literature concerning human sports drug testing that was published between October 2013 and September 2014 is summarized and reviewed in this annual banned-substance review, with particular emphasis on analytical approaches and their contribution to enhanced doping controls.

Trenbolone acetate metabolite transport in rangelands and irrigated pasture: observations and conceptual approaches for agro-ecosystems.

To assess the relative ecological risks of trenbolone acetate (TBA) use in agro-ecosystems, we evaluated the spatiotemporal dynamics of TBA metabolite transport during irrigation and rainfall events. Within a pasture, TBA-implanted heifers (40 mg TBA, 8 mg estradiol) were briefly penned (24 h) at high stocking densities (500 animal units (AU)/ha), prior to irrigation. Irrigation runoff concentrations of 17α-trenbolone (17α-TBOH) 0.3 m downslope were 11 ng/L in the wetting front, but quickly decreased to ∼0.5 ng/L, suggesting mass transfer limitations to transport. At 3 and 30 m downslope, efficient attenuation of 17α-TBOH concentrations is best explained by infiltration and surface partitioning. At plot scales, transport through vegetated filter strips resulted in <0.5-7 ng/L 17α-TBOH concentrations in rainfall-induced runoff with partial subsequent attenuation. Thus, even under intense grazing scenarios, TBA-metabolite transport potential is expected to be low in rangelands, with ecological risks primarily arising from uncontrolled animal access to receiving waters. However, 17α-TBOH concentrations in initial runoff were predicted to exceed threshold levels (i.e., no observed adverse effect levels [NOAELs]) for manure concentrations exceeding 2.0 ng/g-dw, which occurs throughout most of the implant life. For comparison, estrone and 17ß-estradiol were modeled and are likely capable of exceeding NOAELs by a factor of ∼2-5 in irrigation runoff, suggesting that both endogenous and exogenous steroids contribute to endocrine disruption potential in agro-ecosystems.