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1.
Rapid Commun Mass Spectrom ; 38(22): e9902, 2024 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-39226915

RESUMEN

RATIONALE: Anabolic steroids, also known as anabolic-androgenic steroids (AAS), encompass steroidal androgens such as testosterone, as well as synthetic counterparts with similar structures and effects. The misuse of AAS has increased over the years, leading to ethical and welfare concerns in sports. The World Anti-Doping Agency (WADA) and the International Federation for Equestrian Sports (FEI) have banned AAS in relevant sports. Methandienone is one of the most identified anabolic androgenic steroids in sports drug testing, Therefore, reliable detection methods are crucial for effective doping control and maintaining the integrity of the sports. METHODS: This study explores the use of homogenized camel liver for detecting methandienone metabolites in camels. The biotransformation pathways of methandienone in homogenized camel liver tissues are analyzed using Liquid Chromatography-High Resolution Mass Spectrometry (LC-HRMS) to identify and characterize the phase I and phase II metabolites. Chromatographic separation was achieved using a Thermo-Hypersil C18 column. RESULTS: The study has identified 11 methandienone metabolites (M1-M11), this includes 10 phase I and one phase II metabolite. A glucuronic acid conjugate of methandienone was observed in this study, but no sulfonic acid conjugations were found. The metabolites and their possible chemical structures, along with their fragmentation patterns are confirmed using MSMS (MS2) experiments in data-independent acquisition (DIA) mode. CONCLUSIONS: These findings serve as a vital tool for the rapid detection of methandienone, combating its illicit use in camel racing. Comprehensive screenings covering both the parent drug and its metabolites are recommended to improve detection accuracy and ensure regulatory compliance in sports doping. Future research should explore methandienone's metabolite profile in administered camel samples.


Asunto(s)
Anabolizantes , Camelus , Doping en los Deportes , Hígado , Detección de Abuso de Sustancias , Animales , Doping en los Deportes/prevención & control , Detección de Abuso de Sustancias/métodos , Hígado/metabolismo , Hígado/química , Anabolizantes/análisis , Anabolizantes/metabolismo , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Metandrostenolona/metabolismo , Metandrostenolona/análisis , Metandrostenolona/química , Cromatografía Líquida con Espectrometría de Masas
2.
Sci Rep ; 14(1): 20793, 2024 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-39242643

RESUMEN

Intellectual drug doping in athletics by using stimulants that affect central nervous system functions has been diversified. Stimulants are regulated by the World Anti-Doping Agency according to their levels of urinary concentration. Positron emission tomography could evaluate how stimulants affect central nervous system functions. We aimed to evaluate the effect of stimulants on brain function by examining the difference in brain dopamine transporter occupancy by PET after administration of dl-methylephedrine or pseudoephedrine at the clinical maximum daily dose. Four PET scans without and with drug administration (placebo, dl-methylephedrine 150 mg and pseudoephedrine 240 mg) were performed. The concentrations of dl-methylephedrine and pseudoephedrine in plasma and urine were measured. DAT occupancies in the striatum with placebo, dl-methylephedrine and pseudoephedrine were calculated by PET images. The urinary concentration of dl-methylephedrine (12.7 µg/mL) exceeded the prohibited concentration (10 µg/mL), but the DAT occupancy with dl-methylephedrine (6.1%) did not differ (p = 0.92) from that with placebo (6.2%). By contrast, although the urinary concentration of pseudoephedrine (144.8 µg/mL) was below the prohibited concentration (150 µg/mL), DAT occupancy with pseudoephedrine was 18.4%, which was higher than that with placebo (p = 0.009). At the maximum clinical dose, dl-methylephedrine was shown to have weaker effects on brain function than pseudoephedrine.


Asunto(s)
Encéfalo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática , Tomografía de Emisión de Positrones , Seudoefedrina , Humanos , Masculino , Tomografía de Emisión de Positrones/métodos , Seudoefedrina/farmacología , Seudoefedrina/administración & dosificación , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagen , Adulto , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Adulto Joven , Estimulantes del Sistema Nervioso Central/farmacología , Estimulantes del Sistema Nervioso Central/orina , Estimulantes del Sistema Nervioso Central/administración & dosificación , Doping en los Deportes/prevención & control , Femenino , Efedrina/análogos & derivados
3.
Nutrients ; 16(16)2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39203804

RESUMEN

Background: Excessive or improper use of dietary supplements (DSs) by athletes may cause adverse effects, such as impaired performance or failing a doping test, making it important for athletes to mitigate risk and make well-informed choices when using supplements. Methods: This study used focus group interviews to examine the attitudes, motivations, and practices related to DSs among male elite ice hockey players. Results: The players used a wide range of products, ranging from vitamins to multi-ingredient pre-workout supplements. Consuming DSs was considered as a practical and convenient way to ingest sufficient calories to gain or maintain the body weight and muscle mass needed to meet the physical requirements of the sport. The athletes demonstrated a lenient and ignorant attitude when acquiring and using supplements, with a non-critical trust in the guidance provided to them by the coach or physician. Having completed basic anti-doping education in the form of an e-learning program did not appear to result in taking a more careful approach to using DSs. Conclusions: Through their DS practices, elite ice hockey players may put themselves at risk for anti-doping rule violations. A comprehensive approach is needed when aiming to prevent unintentional doping in this athlete cohort.


Asunto(s)
Atletas , Rendimiento Atlético , Suplementos Dietéticos , Doping en los Deportes , Hockey , Motivación , Humanos , Masculino , Doping en los Deportes/prevención & control , Adulto Joven , Atletas/psicología , Adulto , Grupos Focales , Conocimientos, Actitudes y Práctica en Salud , Peso Corporal
5.
Biosens Bioelectron ; 263: 116631, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39111252

RESUMEN

With significant advancements in understanding gene functions and therapy, the potential misuse of gene technologies, particularly in the context of sports through gene doping (GD), has come to the forefront. This raises concerns regarding the need for point-of-care testing of various GD candidates to counter illicit practices in sports. However, current GD detection techniques, such as PCR, lack the portability required for on-site multiplexed detection. In this study, we introduce an integrated microfluidics-based chip for multiplexed gene doping detection, termed MGD-Chip. Through the strategic design of hydrophilic and hydrophobic channels, MGD-Chip enables the RPA and CRISPR-Cas12a assays to be sequentially performed on the device, ensuring minimal interference and cross-contamination. Six potential GD candidates were selected and successfully tested simultaneously on the platform within 1 h. Demonstrating exceptional specificity, the platform achieved a detection sensitivity of 0.1 nM for unamplified target plasmids and 1 aM for amplified ones. Validation using mouse models established by injecting IGFI and EPO transgenes confirmed the platform's efficacy in detecting gene doping in real samples. This technology, capable of detecting multiple targets using portable elements, holds promise for real-time GD detection at sports events, offering a rapid, highly sensitive, and user-friendly solution to uphold the integrity of sports competitions.


Asunto(s)
Técnicas Biosensibles , Sistemas CRISPR-Cas , Doping en los Deportes , Interacciones Hidrofóbicas e Hidrofílicas , Dispositivos Laboratorio en un Chip , Sistemas CRISPR-Cas/genética , Doping en los Deportes/prevención & control , Animales , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Ratones , Humanos , Eritropoyetina/genética , Eritropoyetina/análisis , Diseño de Equipo , Proteínas Asociadas a CRISPR/genética , Proteínas Bacterianas , Endodesoxirribonucleasas
6.
J Mass Spectrom ; 59(8): e5077, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39102231

RESUMEN

The synthetic 20-keto-steroid S42 (1) demonstrated selective androgen receptor modulator (SARM) properties in preclinical studies and, consequently, received growing attention also in the context of sports drug testing programs. Fundamental understanding of the behavior of S42 (1) and of relevant derivatives in gas chromatography-electron ionization MS experiments at high resolution (GC-EI-HRMS) is indispensable to develop a reliable qualitative and quantitative doping control method for S42 (1) and its metabolites in body fluid matrices. We present important fundamental mechanistic data on the EI fragmentation behavior of S42 (1) and of silyl ether derivatives as well as of stable isotope-labelled reference material.


Asunto(s)
Doping en los Deportes , Cromatografía de Gases y Espectrometría de Masas , Receptores Androgénicos , Cromatografía de Gases y Espectrometría de Masas/métodos , Doping en los Deportes/prevención & control , Humanos , Receptores Androgénicos/metabolismo , Receptores Androgénicos/análisis , Receptores Androgénicos/química , Anabolizantes/análisis , Anabolizantes/química , Detección de Abuso de Sustancias/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Andrógenos/análisis , Andrógenos/química , Esteroides/análisis , Esteroides/química
8.
Biochem Med (Zagreb) ; 34(3): 030501, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39171092

RESUMEN

Laboratory medicine in sport and exercise has significantly developed during the last decades with the awareness that physical activity contributes to improved health status, and is present in monitoring both professional and recreational athletes. Training and competitions can modify concentrations of a variety of laboratory parameters, so the accurate laboratory data interpretation includes controlled and known preanalytical and analytical variables to prevent misleading interpretations. The paper represents a comprehensive summary of the lectures presented during the 35th Annual Symposium of the Croatian Society of Medical Biochemistry and Laboratory Medicine. It describes management of frequent sport injuries and sums up current knowledge of selected areas in laboratory medicine and sports including biological variation, changes in biochemical parameters and glycemic status. Additionally, the paper polemicizes sex hormone disorders in sports, encourages and comments research in recreational sports and laboratory medicine. In order to give the wider view, the connection of legal training protocols as well as monitoring prohibited substances in training is also considered through the eyes of laboratory medicine.


Asunto(s)
Deportes , Humanos , Medicina Deportiva , Doping en los Deportes/prevención & control , Traumatismos en Atletas/prevención & control
9.
Clin Chim Acta ; 562: 119890, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39067499

RESUMEN

In case of an adverse analytical finding, a low (estimate) urine concentration can be the consequence of 2 very different situations: it can be the tail end of a drug voluntarily consumed to enhance athletic performance, even by microdosing (which is not effective for all drugs), or it can be the result of a contamination, irrespective of its source. For numerous doping agents, a hair test can allow discriminating doping from contamination based on the measured concentration or even the absence of the target drug. Given hair produces incremental concentrations, its analysis offers the possibility of establishing a pattern of drug use and thus, verifying self-reported histories of exposure. In order to provide a retrospective calendar of drug use, segmental analysis of the hair strand can be performed. In doping, the usual practice is to test the substance in short segments, such as 1 cm to avoid drug dilution when using larger segments. During the last months, seven athletes have returned an adverse analytical finding for the diuretic chlortalidone, with reported urine concentrations in the range 20 to 50 ng/mL. All these athletes submitted, via their legal team, their hair for establishing a pattern of exposure. Results were always consistent with incidental contamination (hair concentration lower than 5 pg/mg), although the source of contamination was never identified. The interpretation of the findings was established in the light of the limited literature, including hair tests after microdosing and therapeutic use.


Asunto(s)
Cabello , Detección de Abuso de Sustancias , Humanos , Cabello/química , Detección de Abuso de Sustancias/métodos , Doping en los Deportes/prevención & control , Masculino , Femenino , Adulto , Clortalidona/análisis , Clortalidona/administración & dosificación , Relación Dosis-Respuesta a Droga , Límite de Detección
10.
Biomed Chromatogr ; 38(9): e5946, 2024 Sep.
Artículo en Francés | MEDLINE | ID: mdl-38978171

RESUMEN

Kisspeptin-10 is a peptide hormone capable of increasing circulating follicle-stimulating hormone, luteinizing hormone and testosterone levels in humans. Clinically, these effects suggest its use as a treatment for infertility. However, its testosterone-increasing effect indicates potential misuse in sports. As such, it is included in the 2024 World Anti-Doping Agency Prohibited List. This work describes the successful validation of an initial testing procedure (screening) and a confirmation procedure for kisspeptin-10 in urine using liquid chromatography-mass spectrometry. Additionally, kisspeptin-10 was incubated in human serum to mimic endogenous metabolism to improve method sensitivity, as previous research had demonstrated a rapid elimination time of only 30 min after injection (in rats). Four metabolites, corresponding to peptide fragments y9, y8, y7 and y5, were found and added to the ITP in full scan mode. A degradation product discovered during early experimentation was found to probably be caused by oxidation of the tryptophan residue into a kynurenine residue. Further research should elucidate the kinetic parameters of the reaction to improve product stability. Using the validated confirmation procedure, a black-market vial of kisspeptin-10 was analysed. The product contained no unexpected impurities, although it appeared to have undergone more degradation than the purchased reference standard.


Asunto(s)
Doping en los Deportes , Kisspeptinas , Espectrometría de Masas , Kisspeptinas/orina , Kisspeptinas/química , Humanos , Doping en los Deportes/prevención & control , Espectrometría de Masas/métodos , Reproducibilidad de los Resultados , Cromatografía Liquida/métodos , Límite de Detección , Modelos Lineales , Cromatografía Líquida de Alta Presión/métodos , Detección de Abuso de Sustancias/métodos
13.
J Pharm Biomed Anal ; 249: 116343, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39053097

RESUMEN

The use of prohibited substances in horse racing is a major concern that jeopardizes both the fairness of competitions and the health of horses. This problem can stem from the use of licensed drugs for animal health, as well as unlicensed substances. Horse doping laboratories monitor the potential use of these substances in racehorses within the framework of regulations set by the International Federation of Horse Racing Authority. In this context, sildenafil and its major metabolite n-desmethyl sildenafil were detected in a post-race horse urine sample sent to the Pendik Veterinary Control Institute Doping Control Laboratory through a screening analysis performed with Liquid Chromatography Triple Quadrupole Mass Spectrometry. These results were confirmed by Q Exactive Orbitrap Mass Spectrometry and follow-up analyses were performed. As a result of these analyses; simultaneous detection of 9 metabolites in horse urine was reported, two of them for the first time. In addition, the pioneer and comprehensive data resulting from this study provide preliminary data for future studies and anti-doping analyses.


Asunto(s)
Doping en los Deportes , Citrato de Sildenafil , Detección de Abuso de Sustancias , Caballos/orina , Citrato de Sildenafil/orina , Animales , Doping en los Deportes/prevención & control , Detección de Abuso de Sustancias/métodos , Detección de Abuso de Sustancias/veterinaria , Espectrometría de Masas en Tándem/métodos , Cromatografía Liquida/métodos
14.
J Sep Sci ; 47(14): e2400003, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39034895

RESUMEN

Furosemide (FUR), banned in sports events by the World Anti-Doping Agency, is a key target in drug tests, necessitating a pretreatment material capable of selectively, rapidly, and sufficiently separating/enriching analytes from complex matrices. Herein, a metal-mediated magnetic molecularly imprinted polymer (mMIP) was rationally designed and synthesized for the specific capture of FUR. The preparations involved the utilization of chromium (III) as the binding pivot, (3-aminopropyl)triethoxysilane as functional monomer, and Fe3O4 as core, all assembled via free radical polymerization. Both the morphologies and adsorptive properties of the mMIP were characterized using multiple methods. The resulting Cr(III)-mediated mMIP (ChM-mMIP) presented excellent selectivity and specificity toward FUR. Under optimized conditions, the adsorption capacity reached 128.50 mg/g within 10 min, and the imprinting factor was 10.41. Moreover, it was also successfully applied as a dispersive solid-phase extraction material, enabling the detection of FUR concentration as low as 20 ng/mL in human urine samples when coupled with a high-performance liquid chromatography/photodiode array. Overall, this study offers a valuable strategy for the development of novel recognition material.


Asunto(s)
Furosemida , Polímeros Impresos Molecularmente , Humanos , Furosemida/orina , Furosemida/química , Polímeros Impresos Molecularmente/química , Adsorción , Impresión Molecular , Extracción en Fase Sólida , Propiedades de Superficie , Cromatografía Líquida de Alta Presión , Tamaño de la Partícula , Doping en los Deportes/prevención & control , Polímeros/química , Polímeros/síntesis química
15.
Talanta ; 277: 126358, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38879944

RESUMEN

Ambient ionization mass spectrometry allows for analysis of samples in their natural state, i.e., with no sample pre-treatment. It can be viewed as a fast, simple, and economical analysis, but its main disadvantages include a lower analytical performance due to the presence of complex sample matrix and the lack of chromatographic separation prior to the introduction of the sample into the mass spectrometer. Here we present an application of two ambient ionization mass spectrometry techniques, i.e., Desorption Atmospheric Pressure Photoionization and Dielectric Barrier Discharge Ionization, for the analysis of known Selective Androgen Receptor Modulators, which represent common compounds of abuse in professional and semiprofessional sport. Eight real samples of illegal food supplements, seized by the local law enforcement, were used to test the performance of the ambient mass spectrometry and the results were validated against a newly developed targeted LC-UV-MS/MS method performed in multiple reaction monitoring mode with an external calibration for each analyte. In order to decide whether or not the compound can be declared as present, we proposed a system of rules for the interpretation of the obtained spectra. The criteria are based on mass spectrum matching (5-10 ppm accuracy from the theoretical exact mass and a correct isotopic pattern), duration of the mass signal (three or five consecutive scans, depending on the instrumentation used), and intensity above the background noise (threefold increase in intensity and absolute intensity above 5E4 or 1E5, depending on the instrumentation). When applying these criteria, good agreement was found between the tested methods. Ambient ionization techniques were effective at detecting SARMs at pharmacologically relevant doses, i.e., approximately above 1 mg per capsule, although they may fail to detect lower levels or isomeric species. It is demonstrated that when adhering to a set of clear and consistent rules, ambient mass spectrometry can be employed as a qualitative technique for the screening of illegal SARMs with sufficient confidence and without the necessity to perform a regular LC-MS analysis.


Asunto(s)
Receptores Androgénicos , Receptores Androgénicos/metabolismo , Doping en los Deportes/prevención & control , Espectrometría de Masas/métodos , Espectrometría de Masas en Tándem/métodos , Suplementos Dietéticos/análisis , Detección de Abuso de Sustancias/métodos , Antagonistas de Receptores Androgénicos/análisis , Humanos , Cromatografía Liquida/métodos
16.
Rev Infirm ; 73(302): 27-28, 2024.
Artículo en Francés | MEDLINE | ID: mdl-38901907

RESUMEN

Several national and international organisations are involved in doping prevention. The aim is to guarantee athletes' health and fairness in competitions. Accurate and regularly updated information is available to help prevent the physical and psychological complications associated with doping.


Asunto(s)
Doping en los Deportes , Doping en los Deportes/prevención & control , Doping en los Deportes/psicología , Humanos
17.
Rapid Commun Mass Spectrom ; 38(17): e9846, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38923663

RESUMEN

RATIONALE: Lomerizine (LMZ) is an antimigraine drug that works as a calcium channel blocker and has selective effects on the central nervous system. It is metabolized into trimetazidine (TMZ), which is a prohibited substance owing to its performance-enhancing effects in both human and animal sports. Effective doping control measures are imperative to distinguish the source of TMZ in samples to ensure integrity and fairness of the sport, therefore a comprehensive analysis of LMZ metabolites is essential to identify potential biomarkers in camel urine for effective doping control. METHODS: Camel urine samples were collected from four healthy animals following a single oral administration of LMZ at a dosage of 1 mg/kg body weight. In vitro studies were conducted using homogenized camel liver samples. Lomerizine and its metabolites were extracted using solid-phase extraction and analyzed with a Thermo Fisher Orbitrap Exploris liquid chromatography mass spectrometry system. The acquired data was processed with the Compound Discoverer software. RESULTS: The study conducted a comprehensive analysis of LMZ metabolites in camels and identified 10 phase I and one phase II metabolites. The primary pathway for the formation of phase I metabolites was de-alkylation, while phase II metabolite was formed through alkylation of the parent drug. The study provided valuable insights into the unique metabolic pathways of LMZ in camels under specific experimental conditions. CONCLUSION: The developed method enables the detection and characterization of LMZ and its metabolites in camels. The identified metabolites has the potential to act as marker metabolites for the distinctive detection of LMZ in camel urine to ensure efficient analytical strategies for routine doping control applications.


Asunto(s)
Camelus , Doping en los Deportes , Animales , Doping en los Deportes/prevención & control , Piperazinas/orina , Piperazinas/metabolismo , Espectrometría de Masas/métodos , Detección de Abuso de Sustancias/métodos , Detección de Abuso de Sustancias/veterinaria , Cromatografía Liquida/métodos , Masculino
18.
Rapid Commun Mass Spectrom ; 38(17): e9856, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38945695

RESUMEN

RATIONALE: To uphold the integrity of horseracing and equestrian sports, it is critical for an equine doping control laboratory to develop a comprehensive screening method to cover a wide range of target substances at the required detection levels in equine urine. METHODS: The procedure involved the enzymatic hydrolysis of 3 mL urine samples followed by solid-phase extraction using HF Bond Elut C18 cartridge. The resulting extracts were then separated on a C18 reversed-phase column and analyzed using liquid chromatography/high-resolution mass spectrometry (LC/HRMS) in both electrospray ionization positive and negative modes in two separate injections. The analytical data were obtained in full scan and product ion scan (PIS) modes in an 11 min LC run. RESULTS: The method can detect 1011 compounds (in both positive and negative ion modes). Over 95% of the target compounds have limits of detections (LODs) ≤10 ng/mL, and more than 50% of the LODs are ≤0.5 ng/mL. The lowest LOD can reach down to 0.01 ng/mL. The applicability of the method was demonstrated by the successful detection of prohibited substances in overseas and domestic equine urine samples. CONCLUSIONS: We have successfully developed a regular screening method for equine urine samples that can detect more than 1000 compounds at sub-ppb levels in both positive and negative ion modes with full scan and PIS using LC/HRMS. Furthermore, this method can theoretically be expanded to accommodate an unlimited number of prohibited substances in full-scan mode.


Asunto(s)
Doping en los Deportes , Límite de Detección , Animales , Caballos/orina , Doping en los Deportes/prevención & control , Cromatografía Liquida/métodos , Detección de Abuso de Sustancias/métodos , Detección de Abuso de Sustancias/veterinaria , Espectrometría de Masas/métodos , Extracción en Fase Sólida/métodos , Reproducibilidad de los Resultados
19.
Int J Mol Sci ; 25(11)2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38891955

RESUMEN

There is great concern in equine sport over the potential use of pharmaceutical agents capable of editing the genome or modifying the expression of gene products. Synthetic oligonucleotides are short, single-stranded polynucleotides that represent a class of agents capable of modifying gene expression products with a high potential for abuse in horseracing. As these substances are not covered by most routine anti-doping analytical approaches, they represent an entire class of compounds that are not readily detectable. The nucleotide sequence for each oligonucleotide is highly specific, which makes targeted analysis for these agents problematic. Accordingly, we have developed a non-targeted approach to detect the presence of specific product ions that are not naturally present in ribonucleic acids. Briefly, serum samples were extracted using solid-phase extraction with a mixed-mode cartridge following the disruption of protein interactions to isolate the oligonucleotides. Following the elution and concentration steps, chromatographic separation was achieved utilizing reversed-phase liquid chromatography. Following an introduction to a Thermo Q Exactive HF mass spectrometer using electrospray ionization, analytes were detected utilizing a combination of full-scan, parallel reaction monitoring and all ion fragmentation scan modes. The limits of detection were determined along with the accuracy, precision, stability, recovery, and matrix effects using a representative 13mer oligonucleotide. Following method optimization using the 13mer oligonucleotide, the method was applied to successfully detect the presence of specific product ions in three unique oligonucleotide sequences targeting equine-specific transcripts.


Asunto(s)
Oligonucleótidos , Animales , Caballos/sangre , Oligonucleótidos/sangre , Doping en los Deportes/prevención & control , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Extracción en Fase Sólida/métodos , Límite de Detección
20.
J Steroid Biochem Mol Biol ; 242: 106527, 2024 09.
Artículo en Inglés | MEDLINE | ID: mdl-38710312

RESUMEN

Methyltestosterone (MT) is one of the most frequently misused anabolic androgenic steroids detected in doping control analysis. The metabolism of MT in humans leads to several phase І metabolites and their corresponding phase Ⅱ conjugates. Previous studies have postulated the 3α-sulfoconjugate of 17α-methyl-5ß-androstane-3α,17ß-diol (S2) as principal sulfate metabolite of MT, with a detection window exceeding 10 days. However, a final direct and unambiguous confirmation of the structure of this metabolite is missing until now. In this study, we established an approach to detect and identify S2, using intact analysis by liquid chromatography hyphenated with tandem mass spectrometry (LC-MS/MS) without complex sample pretreatment. An in vitro study yielded the LC-MS/MS reference retention times of all 3-sulfated 17-methylandrostane-3,17-diol diastereomers, allowing for accurate structure assignment of potentially detected metabolites. In an in vivo excretion study with a single healthy male volunteer, the presence of the metabolite S2 was confirmed after a single oral dose of 10 mg MT. The reference standard was chemically synthesized, characterized by accurate mass mass spectrometry (MS) and nuclear magnetic resonance (NMR), and quantified by quantitative NMR (qNMR). Thus, this study finally provides accurate structure information on the S2 metabolite and a direct analytical method for detection of MT misuse. The availability of the reference material is expected to facilitate further evaluation and subsequent analytical method validation in anti-doping research.


Asunto(s)
Doping en los Deportes , Metiltestosterona , Detección de Abuso de Sustancias , Espectrometría de Masas en Tándem , Masculino , Humanos , Metiltestosterona/metabolismo , Metiltestosterona/análisis , Espectrometría de Masas en Tándem/métodos , Cromatografía Liquida/métodos , Detección de Abuso de Sustancias/métodos , Doping en los Deportes/prevención & control , Anabolizantes/metabolismo , Anabolizantes/análisis , Adulto , Cromatografía Líquida con Espectrometría de Masas
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