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1.
J Proteomics ; 149: 85-97, 2016 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-27569051

RESUMO

Small peptides with a molecular weight of <2kDa represent a performance-enhancing substances. However, in vivo studies with human volunteers are limited because most of these peptides are not approved for human consumption. Thus, relevant in vitro models are a basic tool to study their metabolism for anti-doping purposes. To choose the best in vitro model the biotransformation of growth hormone releasing peptides (GHRPs), Desmopressin and TB-500 was investigated using various in vitro systems. High metabolic activity was observed during incubation of GHRPs and TB-500 with human kidney microsomes (HKM) and liver S9 fraction. Peptides degraded through cleavage of all bonds regardless protective modifications in primary structure. HKM and liver S9 fraction demonstrated enzymatic deamidation activity removing C-terminal amide group from all GHRPs. Fewer metabolites were produced during incubation with human serum. The metabolite pattern obtained with commercially available proteases was poor and included nonspecific hydrolyzed compounds. Thus, the maximum diversity of metabolites was achieved with HKM and liver S9 fraction which makes them the most efficient in vitro model systems for peptides biotransformation study. BIOLOGICAL SIGNIFICANCE: Currently, >60 peptide medicines are FDA approved and marketed in the United States as biopharmaceutical products. Approximately 140 peptide drugs are in clinical trials and about 500 therapeutic peptides in preclinical development. There is an emerging interest in small peptides with a molecular weight of <2kDa, which can be used as doping in modern sport due a wide spectrum of their physiological activity. Most of peptide doping products are not yet approved for human use and some of them undergo preclinical or clinical trials, which complicates the study of metabolism in vivo. The investigation of the metabolism with in vitro methods is an alternative that does not require a human participation and an approval by the Ethics Committee.


Assuntos
Dopagem Esportivo , Rim/metabolismo , Fígado/metabolismo , Microssomos Hepáticos/metabolismo , Oligopeptídeos/metabolismo , Peptídeo Hidrolases/metabolismo , Substâncias para Melhoria do Desempenho/metabolismo , Soro/metabolismo , Animais , Biotransformação , Cromatografia Líquida , Desamino Arginina Vasopressina/metabolismo , Feminino , Humanos , Técnicas In Vitro , Masculino , Espectrometria de Massas , Peptídeo Hidrolases/sangue
2.
Drug Test Anal ; 8(9): 940-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26472487

RESUMO

Currently liquid chromatography - mass spectrometry (LC-MS) analysis after solid-phase extraction (SPE) on weak cation-exchange cartridges is a method of choice for anti-doping analysis of small bioactive peptides such as growth hormone releasing peptides (GHRPs), desmoporessin, LHRH, and TB-500 short fragment. Dilution of urine samples with phosphate buffer for pH adjustment and SPE on weak cation exchange microelution plates was tested as a means to increase throughput of this analysis. Dilution using 200 mM phosphate buffer provides good buffering capacity without affecting the peptides recoveries. SPE on microelution plates was performed on Waters Positive Pressure-96 Processor with subsequent evaporation of eluates in nitrogen flow. Though the use of smaller sample volume decreases the pre-concentration factor and increases the limits of detection of 5 out of 17 detected peptides, the recovery, linearity, and reproducibility of the microelution extraction were comparable with cartridge SPE. The effectiveness of protocols was confirmed by analysis of urine samples containing ipamorelin, and GHRP-6 and its metabolites. SPE after urine sample dilution with buffer can be used for faster sample preparation. The use of microelution plates decreases consumption of solvents and allows processing of up to 96 samples simultaneously. Cartridge SPE with manual рН adjustment remains the best option for confirmation. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Peptídeos/isolamento & purificação , Peptídeos/urina , Extração em Fase Sólida/métodos , Detecção do Abuso de Substâncias/métodos , Urinálise/métodos , Cromatografia Líquida de Alta Pressão/métodos , Desamino Arginina Vasopressina/isolamento & purificação , Desamino Arginina Vasopressina/urina , Hormônio Liberador de Gonadotropina/isolamento & purificação , Hormônio Liberador de Gonadotropina/urina , Humanos , Limite de Detecção , Oligopeptídeos/isolamento & purificação , Oligopeptídeos/urina , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
3.
Drug Test Anal ; 7(11-12): 999-1008, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26695487

RESUMO

EPO-Fc proteins have been under investigation as a potential drug for treating anaemia and have shown larger half-life values than other erythropoiesis-stimulating agents (ESAs). Sodium dodecyl sulfate/sodium N-lauroylsarcosinate polyacrylamide gel electrophoresis (SDS/SAR-PAGE) methods and subsequent immunoblotting are used for routine anti-doping analysis. This paper reports that EPO-Fc fusion proteins can be detected in serum samples by isoelectric focusing-polyacrylamide gel electrophoresis (IEF-PAGE) in carrier ampholyte-based gels with a pH 2-6 gradient after removing the Fc part via site-specific IdeS protease cleavage. The IdeS-digested EPO-Fc protein yields three fragments: two Fc fragments and one dimeric EPO-hinge fragment. After IEF-PAGE was followed by double Western blotting with chemiluminescent detection, the dimeric EPO-hinge fragment showed a unique isoelectric pattern, which differed from those of any other currently known analogue of EPO. We observed that the removal of the Fc fragment from EPO-Fc reduced the apparent molecular weight of entire fusion protein and increased its electrophoretic mobility. As a result, the band for the EPO-hinge fragment was located in a region between the rEPO and NESP standards, at which lower amounts of serum proteins are present. Simple and selective protocols for determining the EPO-Fc protein in human serum were developed to extend the methodological anti-doping arsenal. This protocol has been characterized. The limit of detection (LOD) of the IEF-PAGE method was 20 pg, and that of SDS/SAR-PAGE was 15 pg.


Assuntos
Dopagem Esportivo , Eletroforese em Gel de Poliacrilamida , Eritropoetina/sangue , Fragmentos Fc das Imunoglobulinas/sangue , Focalização Isoelétrica , Substâncias para Melhoria do Desempenho/sangue , Proteínas Recombinantes de Fusão/sangue , Detecção do Abuso de Substâncias/métodos , Western Blotting , Calibragem , Cromatografia Líquida , Eletroforese em Gel de Poliacrilamida/normas , Humanos , Focalização Isoelétrica/normas , Ponto Isoelétrico , Medições Luminescentes , Peptídeo Hidrolases/metabolismo , Valor Preditivo dos Testes , Proteólise , Padrões de Referência , Reprodutibilidade dos Testes , Detecção do Abuso de Substâncias/normas , Espectrometria de Massas em Tandem
4.
Drug Test Anal ; 7(10): 919-25, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25869809

RESUMO

Growth hormone releasing peptides (GHRPs) stimulate secretion of endogenous growth hormone and are listed on the World Anti-Doping Agency (WADA) Prohibited List. To develop an effective method for GHRPs anti-doping control we have investigated metabolites of GHRP-1, GHRP-2, GHRP-6, Hexarelin, and Ipamorelin in urine after nasal administration. Each compound was administrated to one volunteer. Samples were collected for 2 days after administration, processed by solid-phase extraction on weak cation exchange cartridges and analyzed by means of nano-liquid chromatography - high resolution mass spectrometry. Six metabolites of GHRP-1 were identified. GHRP-1 in the parent form was not detected. GHRP-1 (2-4) free acid was detected in urine up to 27 h. GHRP-2, GHRP-2 free acid and GHRP-2 (1-3) free acid were detected in urine up to 47 h after administration. GHRP-6 was mostly excreted unchanged and detected in urine 23 h after administration, its metabolites were detectable for 12 h only. Hexarelin and Ipamorelin metabolized intensively and were excreted as a set of parent compounds with metabolites. Hexarelin (1-3) free acid and Ipamorelin (1-4) free acid were detected in urine samples after complete withdrawal of parent substances. GHRPs and their most prominent metabolites were included into routine ultra-pressure liquid chromatography-tandem mass spectrometry procedure. The method was fully validated, calibration curves of targeted analytes were obtained and excretion curves of GHRPs and their metabolites were plotted. Our results confirm that the detection window after GHRPs administration depends on individual metabolism, drug preparation form and the way of administration.


Assuntos
Oligopeptídeos/urina , Espectrometria de Massas em Tandem/métodos , Administração Intranasal , Cromatografia Líquida/métodos , Humanos , Limite de Detecção , Masculino , Oligopeptídeos/administração & dosagem , Oligopeptídeos/metabolismo , Detecção do Abuso de Substâncias/métodos , Urinálise/métodos
5.
Drug Test Anal ; 7(2): 131-42, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25428705

RESUMO

The data are reported for an in vitro metabolism study of two novel synthetic cannabinoids, N-(1-adamantyl)-1-pentyl-1H-indole-3-carboxamide (APICA) and its fluorinated analog N-(1-adamantyl)-1-(5-fluoropentyl)-1H-indole-3-carboxamide (5F-APICA, STS-135), which are active ingredients of smoking mixtures sold in Russia since 2012. The cannabinoids were isolated from herbal mixtures using preparative liquid chromatography and then incubated with human liver microsomes (HLMs). The formed metabolites were characterized by liquid chromatography - triple quadrupole mass spectrometry and high-resolution mass spectrometry with electrospray ionization in positive ion mode. It was found that HLMs produce mono-, di-, and trihydroxylated metabolites, as well as N-desalkyl metabolites, which can be further hydroxylated; the amide bond resisted the metabolic cleavage. For 5F-APICA, a series of oxidative defluorination products formed as well. For in vivo confirmation of the formed in vitro metabolites, spot urine samples from drug users were analyzed with the created method. It was shown that for the detection of APICA abuse, the preferred metabolites are the di- and tri-hydroxylated species, while in case of 5F-APICA, a monohydroxy metabolite is a better target. The N-despentyl (desfluoropentyl) hydroxyadamantyl metabolite also provides good retrospectivity to confirm the administration of any of these cannabinoids.


Assuntos
Adamantano/análogos & derivados , Canabinoides/metabolismo , Drogas Ilícitas/metabolismo , Indóis/metabolismo , Microssomos Hepáticos/metabolismo , Adamantano/análise , Adamantano/metabolismo , Adamantano/urina , Canabinoides/análise , Canabinoides/urina , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Halogenação , Humanos , Drogas Ilícitas/química , Drogas Ilícitas/urina , Indóis/análise , Indóis/urina , Espectrometria de Massas em Tandem
6.
Drug Test Anal ; 6(11-12): 1087-101, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25312500

RESUMO

The laboratory anti-doping services during XXII Winter Olympic and XI Paralympic games in Sochi in 2014 were provided by a satellite laboratory facility located within the strictly secured Olympic Park. This laboratory, established and operated by the personnel of Antidoping Center, Moscow, has been authorized by the World Anti-Doping Agency (WADA) to conduct doping control analyses. The 4-floor building accommodated the most advanced analytical instrumentation and became a place of attraction for more than 50 Russian specialists and 25 foreign experts, including independent observers. In total, 2134 urine and 479 blood samples were delivered to the laboratory and analyzed during the Olympic Games (OG), and 403 urine and 108 blood samples - during the Paralympic Games (PG). The number of erythropoietin tests requested in urine was 946 and 166 at the OG and PG, respectively. Though included in the test distribution plan, a growth hormone analysis was cancelled by the Organizing Committee just before the Games. Several adverse analytical findings have been reported including pseudoephedrine (1 case), methylhexaneamine (4 cases), trimetazidine (1 case), dehydrochloromethyltestosterone (1 case), clostebol (1 case), and a designer stimulant N-ethyl-1-phenylbutan-2-amine (1 case).


Assuntos
Dopagem Esportivo/estatística & dados numéricos , Substâncias para Melhoria do Desempenho/análise , Esportes , Atletas , Transfusão de Sangue , Cromatografia Líquida de Alta Pressão , Eritropoetina/análise , Cromatografia Gasosa-Espectrometria de Massas , Hemoglobinas/análise , Hormônio do Crescimento Humano/análise , Humanos , Concentração de Íons de Hidrogênio , Insulina/análise , Espectrometria de Massas , Padrões de Referência
7.
Drug Test Anal ; 6(11-12): 1160-2, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25331764

RESUMO

Homologous blood transfusion is a prohibited method of blood manipulation that can be used to increase the number of erythrocytes circulating in the blood stream resulting in an increased oxygen transport capacity. In doping controls, homologous blood transfusions are determined by means of a procedure based on the detection of red blood cell phenotypes by flow cytometry. In the past six years, no adverse analytical findings concerning homologous blood transfusions were reported. One explanation for that phenomenon, assuming that athletes have not completely given up this kind of manipulation, would be a more careful selection of potential donors. If such a donor has the same set of minor erythrocyte antigens as the recipient, the established methodology to detect homologous transfusion would fail. We have hypothesized that any athlete can be a potential donor for teammates with the same RhD factor and AB0 blood group. Having analyzed the phenotype of erythrocytes of 535 Russian athletes in various endurance sports, several pairs of athletes with the same phenotype were observed. Based on the frequency of occurrence of red blood cell antigens, the theoretical probability of finding a donor within a team with exactly the same phenotype was calculated, and the existing number of occurrences where two individuals share the same phenotype in the same sport was in fact five times higher than the theoretical probability.


Assuntos
Transfusão de Sangue/métodos , Dopagem Esportivo , Atletas , Eritrócitos/química , Citometria de Fluxo , Humanos , Fenótipo , Federação Russa
8.
Rapid Commun Mass Spectrom ; 28(11): 1194-202, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24760559

RESUMO

RATIONALE: AICAR (5-aminoimidazole-4-carboxamide 1ß-D-ribofuranoside) is prohibited in sport according to rules established by the World Anti-Doping Agency. Doping control laboratories identify samples where AICAR abuse is suspected by measuring its urinary concentration and comparing the observed level with naturally occurring concentrations. As the inter-individual variance of urinary AICAR concentrations is large, this approach requires a complementary method to unambiguously prove the exogenous origin of AICAR. Therefore, a method for the determination of carbon isotope ratios (CIRs) of urinary AICAR has been developed and validated. METHODS: Concentrated urine samples were fractionated by means of liquid chromatography for analyte cleanup. Derivatization of AICAR yielding the trimethylsilylated analog was necessary to enable CIR determinations by gas chromatography/combustion/isotope ratio mass spectrometry. The method was tested for its repeatability and stability over time and a linear mixing model was applied to test for possible isotopic discrimination. A reference population of n = 63 males and females was investigated to calculate appropriate reference limits to differentiate endogenous from exogenous urinary AICAR. These limits were tested by an AICAR elimination study. RESULTS: The developed method fulfills all the requirements for adequate sports drug testing and was found to be fit for purpose. The investigated reference population showed a larger variability in the CIR of AICAR than of the endogenous steroids. Nevertheless, the calculated thresholds for differences between AICAR and endogenous steroids can be applied straightforwardly to evaluate suspicious doping control samples with the same statistical confidence as established e.g. for testosterone misuse. These thresholds enabled the detection of a single oral AICAR administration for more than 40 h. CONCLUSIONS: Determination of thee CIRs is the method of choice to distinguish between an endogenous and an exogenous source of urinary AICAR. The developed method will enable investigations into doping control samples with elevated urinary concentrations of AICAR and clearly differentiate between naturally produced/elevated and illicitly administered AICAR.


Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Isótopos de Carbono/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Ribonucleotídeos/urina , Adulto , Aminoimidazol Carboxamida/urina , Dopagem Esportivo , Feminino , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Br J Sports Med ; 48(10): 801-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24764550

RESUMO

A medical and scientific multidisciplinary consensus meeting was held from 29 to 30 November 2013 on Anti-Doping in Sport at the Home of FIFA in Zurich, Switzerland, to create a roadmap for the implementation of the 2015 World Anti-Doping Code. The consensus statement and accompanying papers set out the priorities for the antidoping community in research, science and medicine. The participants achieved consensus on a strategy for the implementation of the 2015 World Anti-Doping Code. Key components of this strategy include: (1) sport-specific risk assessment, (2) prevalence measurement, (3) sport-specific test distribution plans, (4) storage and reanalysis, (5) analytical challenges, (6) forensic intelligence, (7) psychological approach to optimise the most deterrent effect, (8) the Athlete Biological Passport (ABP) and confounding factors, (9) data management system (Anti-Doping Administration & Management System (ADAMS), (10) education, (11) research needs and necessary advances, (12) inadvertent doping and (13) management and ethics: biological data. True implementation of the 2015 World Anti-Doping Code will depend largely on the ability to align thinking around these core concepts and strategies. FIFA, jointly with all other engaged International Federations of sports (Ifs), the International Olympic Committee (IOC) and World Anti-Doping Agency (WADA), are ideally placed to lead transformational change with the unwavering support of the wider antidoping community. The outcome of the consensus meeting was the creation of the ad hoc Working Group charged with the responsibility of moving this agenda forward.


Assuntos
Dopagem Esportivo/prevenção & controle , Esportes/ética , Consenso , Guias como Assunto , Humanos , Agências Internacionais , Substâncias para Melhoria do Desempenho/análise , Detecção do Abuso de Substâncias/métodos
10.
Drug Test Anal ; 4(10): 745-53, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23042760

RESUMO

Synthetic cannabinoids are the psychotropic compounds frequently identified as active components of smoking mixtures easily available via the Internet in several countries. These herbal blends have become extremely popular as a legal alternative to cannabis-based products and are difficult to detect by regular drug tests. Here we report on an in vitro and in vivo metabolism of AM-2201, 1-[(5-fluoropentyl)-1H-indol-3-yl]-(naphthalen-1-yl)methanone, and UR-144 (KM-X1), (1-pentylindol-3-yl)-(2,2,3,3-tetramethylcyclopropyl)methanone isolated using preparative liquid chromatography from the smoking mixtures sold in Russia. After incubation with human liver microsomes (HLM) as well as with cytochrome isoenzymes 3A4 and 2B6, the metabolic pathways were identified by means of liquid chromatography - triple quadrupole and high resolution mass spectrometry with electrospray ionization in positive mode. It was found that the in vitro reactions include mono- and dihydroxylation, loss of N-alkyl side chain and formation of dihydrodiol metabolites in case of AM-2201. The HLM were found to be superior over the other two isoenzymes for generation of cannabinoid metabolites. Finally, forensic urine samples were analyzed to validate the in vitro data and it has been shown that for both cannabimimetics the recommended screening targets are the monohydroxylated metabolites.


Assuntos
Canabinoides/urina , Drogas Ilícitas/urina , Indóis/urina , Naftalenos/urina , Canabinoides/análise , Canabinoides/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Drogas Ilícitas/química , Drogas Ilícitas/metabolismo , Indóis/análise , Indóis/metabolismo , Microssomos Hepáticos/metabolismo , Naftalenos/análise , Naftalenos/metabolismo , Detecção do Abuso de Substâncias , Espectrometria de Massas em Tandem
11.
Drug Test Anal ; 4(9): 682-91, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22945829

RESUMO

The metabolism of two anabolic steroids - oxymetholone and desoxymethyltestosterone - was reinvestigated to identify new targets potentially valuable for the antidoping analysis. Excretion urine samples from the laboratory reference collection were used in this study. Following fractionation of the urinary extract by means of high performance liquid chromatography (HPLC), each fraction was subjected to gas chromatography-mass spectrometry (GC-MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS) analysis after trimethylsilylation. About 20 metabolites were found for desoxymethyltestosterone and more than 40 for oxymetholone, with many of them being isomeric compounds. In addition to the well-known reduced and hydroxylated metabolites, 18-nor-17,17-dimethyl and 18-nor-17-hydroxymethyl-17-methyl steroids were also identified. Having evaluated all the metabolites in terms of how long they could be detected, we suggest that 18-nor-2ξ,17ß-hydroxymethyl-17α-methyl-5α-androst-13-en-3α-ol is an important marker of oxymetholone abuse. In case of desoxymethyltestosterone, better detectability could be achieved if 18-nor-17,17-dimethyl-5α-androst-13-en-2ξ,3α-diol is monitored. These novel metabolites could be detected using GC-MS/MS at least for 14 days after administration of these anabolic steroids compared to 5-7 days for previously reported metabolites.


Assuntos
Anabolizantes/urina , Androgênios/urina , Androstenóis/urina , Oximetolona/urina , Detecção do Abuso de Substâncias/métodos , Anabolizantes/metabolismo , Androgênios/metabolismo , Androstenóis/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Oximetolona/metabolismo , Espectrometria de Massas em Tandem/métodos
12.
Drug Test Anal ; 4(10): 754-60, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22977012

RESUMO

Peroxisome proliferator-activated receptor-δ (PPARδ) agonists are the drug candidates with potential performance-enhancing properties, and therefore their illegitimate use in sports should be controlled. To simulate the metabolism of PPARδ agonist GW0742, in vitro reactions were performed which demonstrated that the main metabolic pathway is oxidation of the acyclic divalent sulfur to give the respective sulfoxide and sulfone. After being characterized by liquid chromatography-mass spectrometry (LC-MS), these metabolites were evaluated in urine samples collected after a controlled excretion study. For comparative purposes, GW1516 excretion study was also performed. It has been shown that GW1516 and GW0742 are best monitored as the sulfone metabolites which are detectable in urine using LC-MS/MS based procedure up to 40 and 20 days after a single oral dose of 15 mg each, respectively. The unmetabolized compounds are measurable only for a short period of time and at low ng/ml level. The sulfoxide-to-sulfone ratio for both GW1516 and GW0742 changed irregularly in the range of 1:3 to 1:15 depending on time elapsed after administration with a tendency of increasing the ratio with time. The other important finding was that the abundance of GW0742 and its metabolites in urine is about ten times lower than in case of GW1516.


Assuntos
PPAR delta/agonistas , Tiazóis/metabolismo , Tiazóis/urina , Adulto , Cromatografia Líquida , Humanos , Masculino , Espectrometria de Massas em Tandem , Tiazóis/administração & dosagem , Tiazóis/química
13.
J Steroid Biochem Mol Biol ; 128(3-5): 121-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22142641

RESUMO

The biotransformation of dehydrochloromethyltestosterone (DHCMT, 4-chloro-17ß-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-5ß-androstan-3α,16,17ß-triol (M1), 4-chloro-18-nor-17ß-hydroxymethyl,17α-methyl-5ß-androsta-1,13-dien-3α-ol (M2), 4-chloro-18-nor-17ß-hydroxymethyl,17α-methyl-5ß-androst-13-en-3α-ol (M3), its epimer 4-chloro-18-nor-17α-hydroxymethyl,17ß-methyl-5ß-androst-13-en-3α-ol, 4-chloro-18-nor-17ß-hydroxymethyl,17α-methylandrosta-4,13-dien-3α-ol (M4) and its epimer 4-chloro-18-nor-17α-hydroxymethyl,17ß-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-17ß-hydroxymethyl,17α-methylandrosta-1,4,13-trien-3-one and 4-chloro-3α,6ß,17ß-trihydroxy-17α-methyl-5ß-androst-1-en-16-one.


Assuntos
Anabolizantes/farmacocinética , Substâncias para Melhoria do Desempenho/farmacocinética , Detecção do Abuso de Substâncias/métodos , Testosterona/análogos & derivados , Anabolizantes/química , Anabolizantes/metabolismo , Anabolizantes/urina , Métodos Analíticos de Preparação de Amostras , Biotransformação , Cromatografia Líquida de Alta Pressão , Dopagem Esportivo/prevenção & controle , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Isomerismo , Estrutura Molecular , Substâncias para Melhoria do Desempenho/química , Substâncias para Melhoria do Desempenho/metabolismo , Substâncias para Melhoria do Desempenho/urina , Espectrometria de Massas em Tandem , Testosterona/química , Testosterona/metabolismo , Testosterona/farmacocinética , Testosterona/urina
14.
Drug Test Anal ; 3(10): 717-23, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21964865

RESUMO

A method is described for the determination of mesocarb abuse in equestrian sport by combining gradient liquid chromatography and electrospray ionization tandem mass spectrometry. Mesocarb was administrated orally to two horses at a dose of 50 µg/kg. Urine samples were collected up to 120 h post administration. Hydrolyzed and conjugated urine fractions were handled using liquid-liquid extraction (LLE). The identity of the parent drug and metabolites was confirmed using liquid chromatography combined with tandem mass spectrometry (MS/MS). Mesocarb and seven metabolites were detected in horse urine. Mono- and two di-hydroxylated metabolites were the main metabolites observed in horse urine samples. Based on the differences in MS/MS spectra it was supposed that these metabolites were been formed by the hydroxylation of the phenylisopropyl moiety of mesocarb whilst the main process of hydroxylation of mesocarb in human occurred in the phenylcarbamoyl moiety. The main metabolites were almost completely glucuroconjugated. Minor metabolites such as p-hydroxymesocarb and three di-hydroxylated metabolites together with parent mesocarb were also presented in the free urine fraction. This study has shown that two mono- and two di-hydroxylated metabolites are useful for controlling the abuse of mesocarb in horses.


Assuntos
Estimulantes do Sistema Nervoso Central/metabolismo , Dopagem Esportivo , Cavalos/metabolismo , Espectrometria de Massas por Ionização por Electrospray/métodos , Detecção do Abuso de Substâncias/métodos , Sidnonas/metabolismo , Animais , Estimulantes do Sistema Nervoso Central/urina , Cromatografia Líquida/métodos , Cavalos/urina , Sidnonas/urina , Espectrometria de Massas em Tandem/métodos
15.
Toxicol Lett ; 201(2): 101-4, 2011 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-21134425

RESUMO

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


Assuntos
Suplementos Nutricionais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metiltestosterona/análise , Espectrometria de Massas em Tandem/métodos , Dopagem Esportivo , Humanos , Masculino , Metiltestosterona/metabolismo , Pessoa de Meia-Idade , Padrões de Referência
16.
Drug Test Anal ; 2(10): 475-88, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20878897

RESUMO

The use of two separate derivatization procedures with the formation of oxime (hydroxyl ammonium pretreatment) and picolinoyl (mixed anhydride method) derivates of anabolic steroids following HPLC-MS/MS analysis was proposed. The main product ions of obtained derivatives for 21 anabolic steroids were evaluated and fragmentation pathways were compared.The analysis of MS/MS spectra for underivatized steroids versus oxime or picolinoyl derivatives showed that in case of analytes containing conjugated double bonds in sterane core all of the observed MS/MS spectra contained abundant product ions of diagnostic value. The implementation of derivatization procedures to such compounds is useful for upgrading sensitivity or selectivity of the evaluated method. On the other hand, MS/MS spectra of underivatized and oxime analytes without conjugated double bonds in sterane core produce spectra with large amounts of low abundant product ions. Picolinoyl derivatives formation leads to highly specific spectra with product ions of diagnostic value coupled with sensitive and selective analysis at the same time. The intra- and inter-group comparison analysis revealed that fragmentation pathways for underivatized steroids and correspondent oxime derivatives are similar.The obtained oxime and picolinoyl derivatives provided 10-15 times higher ESI response in the HPLC-ESI-MS-selected reaction monitoring (SRM) when compared to those of underivatized molecules in positive HPLC-ESI-MS mode.Due to the laborious sample preparation we suggest to use the performed strategy for confirmation analysis purposes, metabolic studies or while the identification of new steroids or steroid-like substances.


Assuntos
Anabolizantes/urina , Cromatografia Líquida de Alta Pressão/métodos , Esteroides/urina , Espectrometria de Massas em Tandem/métodos , Anabolizantes/química , Humanos , Oximas/química , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray/métodos , Esteroides/química
17.
Eur J Mass Spectrom (Chichester) ; 16(3): 301-12, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20530837

RESUMO

Efficient and comprehensive sports drug testing necessitates frequent updating and proactive, preventive anti-doping research, and the early implementation of new, emerging drugs into routine doping controls is an essential aspect. Several new drugs and drug candidates with potential for abuse, including so-called Rycals (ryanodine receptor calstabin complex stabilizers, for example, S-107), hypoxia-inducible factor (HIF) stabilizers, and peroxisome-proliferator-activated receptor (PPAR) delta agonists (for example, GW1516), were studied using different mass spectrometry- and ion mobility-based approaches, and their gas phase dissociation behaviors were elucidated. The detailed knowledge of fragmentation routes allows a more rapid identification of metabolites and structurally related, presumably "tailor-made", analogs potentially designed for doping purposes. The utility of product ion characterization is demonstrated in particular with GW1516, for which oxidation products were readily identified in urine samples by means of diagnostic fragment ions as measured using high resolution/high accuracy mass spectrometry and higher energy collision-induced dissociation (HCD).


Assuntos
Dopagem Esportivo/prevenção & controle , Espectrometria de Massas/métodos , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Humanos , Espectrometria de Massas por Ionização por Electrospray/métodos , Tiazepinas/análise , Tiazóis/análise , Tiazóis/metabolismo
18.
Forensic Sci Int ; 200(1-3): 141-7, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20430547

RESUMO

Smoking mixtures containing the cannabimimetic indoles may still be available over-the-counter in several countries. Due to the high affinity of these compounds to the cannabinoid receptors, their effective dose is lower than that of the marijuana products resulting in a low concentration of the excreted metabolites accompanied by a higher psychoactive potency. Up to now the in vivo metabolism of the cannabimimetic indoles seems to be insufficiently investigated and no data have been published on an assay of JWH-018 in urine. In this publication the urinary metabolites of JWH-018 are reported. Using gas and liquid chromatography combined with tandem mass spectrometry two main monohydroxylated metabolites were identified in the forensic urine samples. Based on the differences in their electron ionization MS/MS spectra it is supposed that one is formed by hydroxylation of the indole ring whilst the other by hydroxylation of the N-alkyl chain. The main metabolites are almost completely glucuroconjugated, whereas minor ones (N-despentyl hydroxy-, carboxy-, dihydroxy-, and reduced di- and trihydroxy metabolites) were also present in the free fraction. The parent compound was not detected in urine.


Assuntos
Indóis/urina , Naftalenos/urina , Cromatografia Gasosa , Cromatografia Líquida , Feminino , Humanos , Masculino , Extratos Vegetais/urina , Fumar , Espectrometria de Massas em Tandem , Adulto Jovem
19.
Anal Bioanal Chem ; 396(7): 2479-91, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19946680

RESUMO

Since January 2009, the list of prohibited substances and methods of doping as established by the World Anti-Doping Agency includes new therapeutics such as the peroxisome-proliferator-activated receptor (PPAR)-delta agonist GW1516, which is categorized as a gene doping substance. GW1516 has completed phase II and IV clinical trials regarding dyslipidemia and the regulation of the lipoprotein transport in metabolic syndrome conditions; however, its potential to also improve athletic performance due to the upregulation of genes associated with oxidative metabolism and a modified substrate preference that shifted from carbohydrate to lipid consumption has led to a ban of this compound in elite sport. In a recent report, two presumably mono-oxygenated and bisoxygenated urinary metabolites of GW1516 were presented, which could serve as target analytes for doping control purposes after full characterization. Hence, in the present study, phase I metabolism was simulated by in vitro assays employing human liver microsomal fractions yielding the same oxygenation products, followed by chemical synthesis of the assumed structures of the two abundant metabolic reaction products. These allowed the identification and characterization of mono-oxygenated and bisoxygenated metabolites (sulfoxide and sulfone, respectively) as supported by high-resolution/high-accuracy mass spectrometry with higher-energy collision-induced dissociation, tandem mass spectrometry, and nuclear magnetic resonance spectroscopy. Since urine samples have been the preferred matrix for doping control purposes, a method to detect the new target GW1516 in sports drug testing samples was developed in accordance to conventional screening procedures based on enzymatic hydrolysis and liquid-liquid extraction followed by liquid chromatography, electrospray ionization, and tandem mass spectrometry. Validation was performed for specificity, limit of detection (0.1 ng/ml), recovery (72%), intraday and interday precisions (7.7-15.1%), and ion suppression/enhancement effects (<10%).


Assuntos
Fracionamento Químico/métodos , Cromatografia Líquida/métodos , Dopagem Esportivo/prevenção & controle , PPAR delta/agonistas , Espectrometria de Massas por Ionização por Electrospray/métodos , Detecção do Abuso de Substâncias/métodos , Tiazóis/urina , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Urinálise/métodos
20.
Drug Test Anal ; 2(11-12): 643-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21204296

RESUMO

Sulbutiamine (isobutyryl thiamine disulfide) is a lipophilic derivative of thiamine used for the treatment of asthenia and other related pathological conditions. It is available over-the-counter in several countries either as a component of nutritional supplements or as a pharmaceutical preparation. The presence of sulbutiamine in urinary doping control samples was monitored to evaluate the relevance of its use in sports. As one of the sulbutiamine metabolites has very close retention time and the same characteristic ion (m/z 194) as the main boldenone metabolite, the raw data files generated from the screening for anabolic steroids were automatically reprocessed to identify the samples containing sulbutiamine. It was found that of ca. 16 000 samples analyzed in the Russian laboratory during 2009, about 100 samples contained sulbutiamine. It is important to note that most of these samples were collected in-competition, and sulbutiamine concentration was estimated to be greater than 500 ng/ml. This may indicate that sulbutiamine was intentionally administered for its ergogenic and mild stimulating properties.


Assuntos
Dopaminérgicos/urina , Fármacos Atuantes sobre Aminoácidos Excitatórios/urina , Tiamina/análogos & derivados , Dopaminérgicos/metabolismo , Dopagem Esportivo , Fármacos Atuantes sobre Aminoácidos Excitatórios/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Estudos Retrospectivos , Federação Russa , Tiamina/metabolismo , Tiamina/urina
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