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1.
Drug Test Anal ; 16(1): 38-48, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37161689

RESUMEN

Dietary supplements (DS) are intended for healthy people to maintain or improve their overall health. Its consumption is widespread in large part of the general population and at all levels of athletes. Nevertheless, DS use can also pose health risks to individuals and, in the case of athletes, may lead to adverse analytical findings (AAFs) due to the possibility of DS contamination or adulteration with doping agents banned by the World Anti-Doping Agency. Although educational initiatives are being performed in Brazil to warn the sports community about inadvertent doping cases, AAFs connected to the DS administration have been increasingly growing. The findings of DS analyzed by the Brazilian Doping Control Laboratory (LBCD), between 2017 and 2022, after Testing Authorities (TAs) analysis requests, showed an alarming number of tainted samples. Diuretics were the most common adulterants found in all supplement types. However, the profile of prohibited substances in manufactured and compounded dietary supplements (MDS and CDS, respectively) were distinct, with stimulants being most prevalent in MDS and anabolic agents in CDS products. Additionally, MDS samples generally presented higher estimated concentrations of banned substances (mg/g) than CDS samples (µg/g). The common practice of DS intake by athletes continues to be of great concern for a doping-free sport, given the high prevalence of prohibited substances detected in the analyzed samples by the LBCD. The current Brazilian scenario reinforces the importance of raising awareness in the sports community of the possible consequences of an unintentional doping case linked to DS use.


Asunto(s)
Doping en los Deportes , Deportes , Humanos , Brasil , Diuréticos/análisis , Atletas , Suplementos Dietéticos/análisis
2.
J Mass Spectrom ; 55(10): e4593, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32805775

RESUMEN

Dermorphin is a peptide with analgesic actions similar to morphine, but with greater effect and less potential to cause tolerance. The use of dermorphin has been documented in race horses, and its use in humans has already been reported. Considering the potential advantages from the use of dermorphin over morphine, a method to monitor it, and its main metabolite dermorphin (1-4) in humans becomes necessary for doping control. Here, we present two orthogonal methods for this purpose: a high-throughput liquid chromatography coupled to high-resolution mass spectrometry (HRMS) as an initial testing procedure and liquid chromatography-tandem mass spectrometry (MS/MS) in the selected reaction monitoring (SRM) acquisition mode for a confirmation procedure. For urine samples, pretreatment through a mixed-mode weak cation-exchange solid-phase extraction emerged as an effective approach to extract peptides from the biological sample. For the HRMS analysis, a full-MS scan acquisition mode was selected to detect the exact masses of dermorphin and dermorphin (1-4) at m/z 803.37226 and 457.20816, respectively. The SRM method used in the MS/MS confirmation protocol presented high specificity and sensitivity. The selected product ions for dermorphin were 602.2, 202.1 and 574.3 and for dermorphin (1-4) were 207.1, 223.1, and 235.1. Both methods were evaluated for specificity, repeatability, carryover, matrix effects, and recovery. No carryover and matrix effects were detected. The limit of detection for initial testing procedure and the limit of identification for confirmation procedure was 2.5 ng/ml. Also, specificity and robustness were acceptable for the application. Together, the developed methods proved to be efficient for the analysis of dermorphin and metabolite for human doping control purpose.


Asunto(s)
Analgésicos Opioides/orina , Cromatografía Líquida de Alta Presión/métodos , Péptidos Opioides/orina , Espectrometría de Masas en Tándem/métodos , Doping en los Deportes , Humanos , Límite de Detección , Extracción en Fase Sólida/métodos , Detección de Abuso de Sustancias/métodos
3.
Zebrafish ; 17(2): 104-111, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32096703

RESUMEN

Testolactone is a potent steroid aromatase (CYP19A1) inhibitor, and its main effect is a reduction in estradiol and estrone and an increase in testosterone and androstenedione levels. In this work, we evaluated a zebrafish water tank (ZWT) as a model to investigate testolactone biotransformation and the possibility to increase knowledge regarding the applicability of the ZWT on steroid hormone elimination research, as well as on the impact of steroid hormones on the endogenous metabolism of zebrafish. High-resolution mass spectrometry combined with SIEVE software was used to discriminate the peaks of interest based on significant changes in the relative signal intensity of the m/z values between different ZWT experiments. The metabolites, 4,5-dihydrotestolactone and 1,2,4,5-tetrahydrotestolactone, the same metabolites as those described in humans, were detected in ZWT, both in quite similar proportions. The presence of testolactone in the ZWT caused a rise in testosterone and androstenedione in the water tank, similar to that in human serum. These data suggest that, while the concentration of testolactone was high enough to inhibit the aromatase enzyme, an accumulation of androgens in the water occurred, indicating that the ZWT can be considered a model to investigate the impact of steroids on live organisms.


Asunto(s)
Inhibidores de la Aromatasa/metabolismo , Testolactona/metabolismo , Pez Cebra/metabolismo , Animales , Biotransformación , Hormonas Esteroides Gonadales , Testolactona/análogos & derivados
4.
Drug Test Anal ; 10(11-12): 1657-1669, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30341930

RESUMEN

Zebrafish (Danio rerio) water tank (ZWT) approach was investigated as an alternative model for metabolism studies based on six different experiments with four model compounds. Sibutramine was applied for the multivariate optimization of ZWT conditions, also for the comparison of the metabolism among ZWT, humans and mice, beyond for the role of CYP2B6 in ZWT. After the optimization, 18 fish and 168 hours of experiments is the minimum requirement for a relevant panel of biotransformation products. A comparison among the species resulted in the observation of the same hydroxylated metabolites, with differences in metabolites concentration ratio. However, the ZWT allowed tuning of the conditions to obtain a specific metabolic profile, depending on the need. In addition, by utilizing CYP2B6 inhibition, a relevant ZWT pathway for the demethylation of drugs was determined. The stereospecificity of the ZWT metabolism was investigated using selegiline and no racemization or inversion transformations were observed. Moreover, the investigation of metabolism of cannabimimetics was performed using JWH-073 and the metabolites observed are the same described for humans, except for the hydroxylation at the indol group, which was explained by the absence of CYP2C9 orthologs in zebrafish. Finally, hexarelin was used as a model to evaluate studies by ZWT for drugs with low stability. As a result, hexarelin displays a very fast metabolization in ZWT conditions and all the metabolites described for human were observed in ZWT. Therefore, the appropriate conditions, merits, and relevant limitations to conduct ZWT experiments for the investigation of drug metabolism are described.


Asunto(s)
Preparaciones Farmacéuticas/metabolismo , Pez Cebra/metabolismo , Adulto , Animales , Antidepresivos/metabolismo , Antidepresivos/orina , Biotransformación , Ciclobutanos/metabolismo , Ciclobutanos/orina , Citocromo P-450 CYP2B6/metabolismo , Inhibidores del Citocromo P-450 CYP2B6/farmacología , Femenino , Humanos , Hidroxilación , Indoles/metabolismo , Indoles/orina , Masculino , Ratones , Modelos Animales , Naftalenos/metabolismo , Naftalenos/orina , Oligopéptidos/metabolismo , Oligopéptidos/orina , Preparaciones Farmacéuticas/orina , Selegilina/metabolismo , Selegilina/orina , Pez Cebra/orina , Proteínas de Pez Cebra/metabolismo
5.
J Mass Spectrom ; 53(6): 476-503, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29524299

RESUMEN

The number of substances nominally listed in the prohibited list of the World Anti-Doping Agency increases each year. Moreover, many of these substances do not have a single analytical target and must be monitored through different metabolites, artifacts, degradation products, or biomarkers. A new analytical method was developed and validated for the simultaneous analysis of peptides and organic molecules using a single sample preparation and LC-Q-HRMS detection. The simultaneous analysis of 450 target molecules was performed after cleanup on a mixed-mode solid-phase extraction cartridge, combined with untreated urine. The cleanup solvent and reconstitution solvent were the most important parameters for achieving a comprehensive sample preparation approach. A fast chromatographic run based on a multistep gradient was optimized under different flows; the detection of all substances without isomeric coelution was achieved in 11 minutes, and the chromatographic resolution was considered a critical parameter, even in high-resolution mass spectrometry detection. The mass spectrometer was set to operate by switching between positive and negative ionization mode for FULL-MS, all-ion fragmentation, and FULL-MS/MS2 . The suitable parameters for the curved linear trap (c-trap) conditions were determined and found to be the most important factors for the development of the method. Only FULL-MS/MS2 enables the detection of steroids and peptides at concentrations lower than the minimum required performance levels set by World Anti-Doping Agency (1 ng mL-1 ). The combination of the maximum injection time of the ions into the c-trap, multiplexing experiments, and loop count under optimized conditions enabled the method to be applied to over 10 000 samples in only 2 months during the 2016 Rio Summer Olympic and Paralympic Games. The procedure details all aspects, from sample preparation to mass spectrometry detection. FULL-MS data acquisition is performed in positive and negative ion mode simultaneously and can be applied to untargeted approaches.


Asunto(s)
Péptidos/análisis , Esteroides/análisis , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Doping en los Deportes/prevención & control , Humanos , Límite de Detección , Péptidos/orina , Extracción en Fase Sólida/métodos , Esteroides/orina
6.
Subst Use Misuse ; 49(9): 1098-114, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24766455

RESUMEN

This article presents the prevalence of stimulant doping among Brazilian athletes, the analytical approaches used, as well as a general evolution of the detectability of the stimulants being used. Results from the Brazilian accredited doping control laboratory are compared with the global statistics disclosed by the World Anti-Doping Agency. The high prevalence of stimulant doping in Brazil can be attributed to several reasons, including "self-administration," a "body-shaping" culture, and the use of nutritional supplements.


Asunto(s)
Anfetaminas/administración & dosificación , Estimulantes del Sistema Nervioso Central/administración & dosificación , Cocaína/administración & dosificación , Doping en los Deportes/estadística & datos numéricos , Detección de Abuso de Sustancias/métodos , Atletas , Brasil , Humanos , Prevalencia
7.
Drug Test Anal ; 5(8): 619-26, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23339119

RESUMEN

The urinary steroid profile has been used in clinical endocrinology for the early detection of enzyme deficiencies. In the field of doping, its evaluation in urine samples is used to diagnose the abuse of substances prohibited in sport. This profile is influenced by sex, age, exercise, diet, and ethnicity, among others; laboratories own reference ranges might compensate for ethnic differences among population and inter-laboratory biases. This paper shows the reference ranges obtained in the Antidoping Laboratory of Havana for the following steroid profile parameters: ten androgens (testosterone, epitestosterone, androsterone, etiocholanolone, 5α-androstan-3α,17ß-diol, 5ß-androstan-3α,17ß-diol, dehydroepiandrosterone, epiandrosterone, 11ß-hydroxyandrosterone and 11ß-hydroxyetiocholanolone), three estrogens (estradiol, estriol and estrone), two pregnanes (pregnanediol and pregnanetriol) and two corticosteroids (cortisol and tetrahydrocortisol). The urine samples (male: n = 2454 and female: n = 1181) and data obtained are representative of population from Latin-American countries like Cuba, Venezuela, Mexico, Dominican Republic, Guatemala and Chile. Urine samples were prepared by solid-phase extraction followed by enzymatic hydrolysis and liquid-liquid extraction with an organic solvent in basic conditions. Trimethylsilyl derivatives were analyzed by gas chromatography coupled to mass spectrometry. Reference ranges were established for each sex, allowing the determination of abnormal profiles as a first diagnostic tool for the detection of the abuse of androgenic anabolic steroids. The comparison with the Caucasian population confirms that the urinary steroid profile is influenced by ethnicity.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Esteroides/orina , Detección de Abuso de Sustancias/métodos , Corticoesteroides/orina , Andrógenos/orina , Doping en los Deportes , Estrógenos/orina , Femenino , Cromatografía de Gases y Espectrometría de Masas/normas , Hispánicos o Latinos , Humanos , América Latina , Masculino , Pregnanodiol/orina , Pregnanotriol/orina , Valores de Referencia , Sensibilidad y Especificidad , Detección de Abuso de Sustancias/normas
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