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1.
Metabolites ; 13(7)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37512532

RESUMO

The very high intensity of exercise accompanied by mental stress triggers adaptive mechanisms associated with adrenocortical steroidogenesis. However, the association between adrenocortical steroidogenesis and the high intensity of exercise in elite athletes is poorly studied. A significant obstacle to solving this complex task is the wide range (4-5 orders) of steroid concentrations in serum and limitations related to the amount of biological samples taken from professional athletes. To solve this task, we have developed and validated a non-trivial approach for targeted serum metabolic profiling based on the use of LC-MS/MS with dual-polarity electrospray ionization. The developed method based on the proposed approach allows for the quantitative determination of 14 stress resistance biomarkers in elite athletes using a small amount of specimen within 8.5 min.

2.
Artigo em Inglês | MEDLINE | ID: mdl-18708700

RESUMO

The present study is based on the assumption that changes in an ADMA-DDAH-NOS (ADMA-asymmetrical dimethylarginine; DDAH-dimethyl-arginine dimethylaminohydrolase; NOS-nitric oxide synthase) system could be employed as indirect markers for recombinant human erythropoietin (rHuEPO) administration in doping control. We assessed a predictive value of four proposed new markers for rHuEPO abuse. Preliminary data showed that concentrations of ADMA, symmetrical dimethylarginine (SDMA), citrulline and arginine in human urine were increased after administration of a single intravenous erythropoietin injection (2000 U day(-1), Epocrine, St-Petersburg, Russia). The study of variations of ADMA, SDMA, arginine and citrulline levels before and after rHuEPO administration was performed with two healthy male volunteers. Urine samples were collected before rHuEPO administration and urinary concentrations of ADMA and SDMA were determined at 10.0-40 microg mL(-1) and of arginine and citrulline at 0.5-10 microg mL(-1). A single dose injection of rHuEPO caused an increase in ADMA, SDMA, arginine and citrulline concentrations up to 40-270 microg mL(-1), 40-240 microg mL(-1), 10-60 microg mL(-1) and 12-140 microg mL(-1), respectively. These preliminary results indicated that an indirect approach could be used as a pre-screening of urine samples in order to decrease the number of samples with a low probability of rHuEPO abuse and, thus, save costs and human workload.


Assuntos
Dopagem Esportivo , Eritropoetina/urina , Espectrometria de Massas por Ionização por Electrospray/métodos , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem/métodos , Adulto , Amidoidrolases/urina , Arginina/análogos & derivados , Arginina/urina , Biomarcadores/urina , Cromatografia Líquida de Alta Pressão , Citrulina/urina , Eritropoetina/administração & dosagem , Humanos , Injeções Intravenosas , Masculino , Óxido Nítrico Sintase/urina , Valor Preditivo dos Testes , Proteínas Recombinantes , Valores de Referência
3.
Drug Test Anal ; 10(4): 711-722, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28777889

RESUMO

Gonadotropin-releasing hormone (GnRH) and its small peptide synthetic analogues are included in Section S2 of the World Anti-Doping Agency (WADA) Prohibited List as they stimulate pituitary luteinizing hormone (LH) and testicular testosterone (T) secretion. Both the following approaches can be applied for determination of abuse of these peptides: direct identification of intact compounds and their metabolites in athletes' biofluids and evaluation of LH and T concentrations as mediate markers of drug intake. To develop an effective concept for GnRH and its analogues determination in anti-doping control, in vitro and in vivo studies were conducted. A new method was applied to the evaluation of the slow-release profile of buserelin, goserelin, and leuprolide biodegradable microspheres after the intramuscular injection in male volunteers. Eight metabolites of 10 GnRH analogues were identified after incubation with human kidney microsomes, most of them were leuprolide degradation products. Obtained data were added into ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for GnRH analogues determination. The detection time windows for administered peptides and their metabolites in urine samples were evaluated with 2 sample preparation techniques: dilute-and-shoot and solid-phase extraction. To support the second hypothesis, the measurement of LH and the main parameters of the steroid profile were performed in urine samples. Just 1 compound among those investigated resulted in the LH concentration dropping to non-physiological levels. Thus, for doping-control purposes, monitoring of hormone levels fluctuations could be applied only together with longitudinal passport steroid profile data.


Assuntos
Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/urina , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem/métodos , Adulto , Biomarcadores/metabolismo , Biomarcadores/urina , Cromatografia Líquida de Alta Pressão/métodos , Dopagem Esportivo , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/metabolismo , Humanos , Limite de Detecção , Masculino , Extração em Fase Sólida/métodos
4.
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
5.
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
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