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1.
Rapid Commun Mass Spectrom ; 35(12): e9080, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33713366

RESUMO

RATIONALE: The metabolism of arimistane (Arim) was first described in 2015, and androst-3,5-diene-7ß-ol-17-one was proposed as the main metabolite excreted in urine. Recently, a more detailed study describing the findings in urine after the administration of Arim has been published. This study corroborated the previously described metabolite but also described several phase I and II metabolites, analyzing trimethylsilylated urinary extracts using accurate mass spectrometry coupled to gas chromatography (GC/qTOF). The present communication is an extension of this late investigation aiming to implement the results of Arim metabolism using either accurate mass spectrometry and/or triple quadrupole tandem mass spectrometry, both coupled to liquid chromatography (LC/qTOF and LC/QqQ). METHODS: The samples used in this study were the same as previously studied using GC/qTOF. One single oral dose of Arim was administered to three volunteers, and samples collected before and up to 10 h after the Arim administration were analyzed. The unconjugated fraction of urine was removed, and the hydrolysis was performed with ß-glucuronidase from Escherichia coli. The extracts were reconstituted in water:acetonitrile before the LC/qTOF and LC/QqQ analysis. RESULTS: The presence of the proposed metabolites studied using GC was verified by accurate mass measurements. Twelve metabolites not found in the blank urine samples were identified by the accurate mass spectra with acceptable errors between -7.5 and 8.1 ppm: 4 reduced metabolites, 4 monohydroxylated metabolites, and 4 with an additional hydroxylation (bis-hydroxylated metabolites). Unlike in the study carried out using GC/qTOF, Arim itself was found in the samples of the three volunteers. CONCLUSIONS: Twelve metabolites were identified, and specific transitions were proposed. Despite the good results, some limitations remain. As for GC/qTOF, the α- or ß configuration of hydroxy groups, as well as the exact position for some unsaturation, cannot be assigned with certainty. Because certified reference materials of these metabolites are not yet available, the molecular structures were hypothesized considering the previous study using GC.


Assuntos
Substâncias para Melhoria do Desempenho/urina , Preparações Farmacêuticas/urina , Cromatografia Líquida de Alta Pressão/métodos , Dopagem Esportivo/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Estrutura Molecular , Substâncias para Melhoria do Desempenho/química , Urina/química
3.
Tidsskr Nor Laegeforen ; 139(4)2019 02 26.
Artigo em Inglês, Norueguês | MEDLINE | ID: mdl-30808106

RESUMO

BACKGROUND: International studies have shown that 12-58 % of all dietary supplements intended for people who exercise and engage in sports contain substances prohibited by the World Anti-Doping Code (WADC). In some cases, the doping substances are not declared on the product label, and the consumer may therefore be unaware of what he/she ingests. Many of the substances may cause adverse health effects, and sale of such products is illegal in Norway. MATERIAL AND METHOD: To investigate the prevalence of doping substances in dietary supplements sold on the Norwegian market, a total of 93 high-risk products from online shops targeting Norwegian consumers were analysed for substances on the WADC Prohibited List and pharmaceutical drugs. All supplements were marketed as able to boost energy levels and/or having a muscle-building or fat-burning effect. The products were selected on the basis of tips received, online forums and/or international lists. RESULTS: Altogether 21 of 93 (23 %) products analysed contained prohibited substances, pharmaceutical drugs and/or illegal amounts of caffeine. Substances on the WADC Prohibited List were detected in 8 of the 93 (9 %) dietary supplements. All products containing doping substances were declared as containing one or more banned substances. INTERPRETATION: The results show that using apparently legal dietary supplements purchased in online shops targeting Norwegian consumers involves a risk of inadvertent doping and adverse health effects.


Assuntos
Suplementos Nutricionais/análise , Substâncias para Melhoria do Desempenho/química , Anabolizantes/química , Fármacos Antiobesidade/química , Cafeína/química , Dopagem Esportivo , Humanos , Internet , Noruega , Preparações Farmacêuticas/química
4.
Pharm Res ; 35(2): 41, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29404794

RESUMO

PURPOSE: The aim of this study is to use computational approaches to predict the ADME-Tox profiles, pharmacokinetics, molecular targets, biological activity spectra and side/toxic effects of 31 anabolic and androgen steroids in humans. METHODS: The following computational tools are used: (i) FAFDrugs4, SwissADME and admetSARfor obtaining the ADME-Tox profiles and for predicting pharmacokinetics;(ii) SwissTargetPrediction and PASS online for predicting the molecular targets and biological activities; (iii) PASS online, Toxtree, admetSAR and Endocrine Disruptomefor envisaging the specific toxicities; (iv) SwissDock to assess the interactions of investigated steroids with cytochromes involved in drugs metabolism. RESULTS: Investigated steroids usually reveal a high gastrointestinal absorption and a good oral bioavailability, may inhibit someof the human cytochromes involved in the metabolism of xenobiotics (CYP2C9 being the most affected) and reflect a good capacity for skin penetration. There are predicted numerous side effects of investigated steroids in humans: genotoxic carcinogenicity, hepatotoxicity, cardiovascular, hematotoxic and genitourinary effects, dermal irritations, endocrine disruption and reproductive dysfunction. CONCLUSIONS: These results are important to be known as an occupational exposure to anabolic and androgenic steroids at workplaces may occur and because there also is a deliberate human exposure to steroids for their performance enhancement and anti-aging properties.


Assuntos
Anabolizantes/farmacologia , Androgênios/farmacologia , Modelos Biológicos , Substâncias para Melhoria do Desempenho/farmacologia , Anabolizantes/química , Androgênios/química , Atletas , Simulação por Computador , Drogas Desenhadas/química , Drogas Desenhadas/farmacologia , Interações Medicamentosas , Uso Indevido de Medicamentos/efeitos adversos , Humanos , Simulação de Acoplamento Molecular , Exposição Ocupacional/efeitos adversos , Substâncias para Melhoria do Desempenho/química , Absorção Cutânea , Drogas Veterinárias/química , Drogas Veterinárias/farmacologia , Local de Trabalho
5.
JAMA ; 318(20): 2004-2010, 2017 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-29183075

RESUMO

Importance: Recent reports have described the increasing use of nonsteroidal selective androgen receptor modulators, which have not been approved by the US Food and Drug Administration (FDA), to enhance appearance and performance. The composition and purity of such products is not known. Objective: To determine the chemical identity and the amounts of ingredients in dietary supplements and products marketed and sold through the internet as selective androgen receptor modulators and compare the analyzed contents with product labels. Design and Setting: Web-based searches were performed from February 18, 2016, to March 25, 2016, using the Google search engine on the Chrome and Internet Explorer web browsers to identify suppliers selling selective androgen receptor modulators. The products were purchased and the identities of the compounds and their amounts were determined from April to August 2016 using chain-of-custody and World Anti-Doping Association-approved analytical procedures. Analytical findings were compared against the label information. Exposures: Products marketed and sold as selective androgen receptor modulators. Main Outcomes and Measures: Chemical identities and the amount of ingredients in each product marketed and sold as selective androgen receptor modulators. Results: Among 44 products marketed and sold as selective androgen receptor modulators, only 23 (52%) contained 1 or more selective androgen receptor modulators (Ostarine, LGD-4033, or Andarine). An additional 17 products (39%) contained another unapproved drug, including the growth hormone secretagogue ibutamoren, the peroxisome proliferator-activated receptor-δ agonist GW501516, and the Rev-ErbA agonist SR9009. Of the 44 tested products, no active compound was detected in 4 (9%) and substances not listed on the label were contained in 11 (25%). In only 18 of the 44 products (41%), the amount of active compound in the product matched that listed on the label. The amount of the compounds listed on the label differed substantially from that found by analysis in 26 of 44 products (59%). Conclusions and Relevance: In this limited investigation involving chemical analyses of 44 products marketed as selective androgen receptor modulators and sold via the internet, most products contained unapproved drugs and substances. Only 52% contained selective androgen receptor modulators and many were inaccurately labeled.


Assuntos
Anabolizantes/química , Comércio , Rotulagem de Medicamentos , Internet , Substâncias para Melhoria do Desempenho/química , Receptores Androgênicos , Acetamidas/análise , Aminofenóis/análise , Anilidas/análise , Aprovação de Drogas , Tráfico de Drogas , Nitrilas/análise , Pirrolidinas/análise , Estados Unidos , United States Food and Drug Administration
6.
Int J Sport Nutr Exerc Metab ; 25(4): 396-404, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25675030

RESUMO

Whenever athletes willfully or accidentally ingest performance-enhancing drugs or other banned substances (such as drugs of abuse), markers of those drugs can be detected in biological samples (e.g., biofluids: urine, saliva, blood); in the case of some drugs, that evidence can be apparent for many weeks following the last exposure to the drug. In addition to the willful use of prohibited drugs, athletes can accidentally ingest banned substances in contaminated dietary supplements or foods and inadvertently fail a drug test that could mean the end of an athletic career and the loss of a good reputation. The proliferation of performance-enhancing drugs and methods has required a corresponding increase in the analytical tools and methods required to identify the presence of banned substances in biofluids. Even though extraordinary steps have been taken by organizations such as the World Anti-Doping Agency to limit the use of prohibited substances and methods by athletes willing to cheat, it is apparent that some athletes continue to avoid detection by using alternative doping regimens or taking advantage of the limitations in testing methodologies. This article reviews the testing standards and analytical techniques underlying the procedures used to identify banned substances in biological samples, setting the stage for future summaries of the testing required to establish the use of steroids, stimulants, diuretics, and other prohibited substances.


Assuntos
Suplementos Nutricionais/efeitos adversos , Dopagem Esportivo/história , Guias como Assunto , Substâncias para Melhoria do Desempenho/efeitos adversos , Fenômenos Fisiológicos da Nutrição Esportiva , Testes de Toxicidade/métodos , Atletas , Biomarcadores/análise , Suplementos Nutricionais/análise , Suplementos Nutricionais/normas , Dopagem Esportivo/prevenção & controle , Controle de Medicamentos e Entorpecentes , Contaminação de Alimentos , História do Século XX , História do Século XXI , Humanos , Política Nutricional , Cooperação do Paciente , Substâncias para Melhoria do Desempenho/análise , Substâncias para Melhoria do Desempenho/química , Substâncias para Melhoria do Desempenho/normas , Esportes/história , Fenômenos Fisiológicos da Nutrição Esportiva/efeitos dos fármacos , Testes de Toxicidade/tendências
7.
Electrophoresis ; 33(7): 1087-94, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22539311

RESUMO

Hemoglobin-based oxygen carriers (HBOCs) are blood substitutes, synthesized by polymerizing hemoglobin, which are being developed and investigated as alternatives to blood for medical purposes. However, due to their ability to increase the oxygen carrying capacity when taken by healthy individuals, HBOCs have been used as a doping agent among endurance athletes and are included in the World Anti-Doping Agency's Prohibited List. To maintain the fairness of competitions and continue the battle against doping, it is essential to be able to detect HBOCs if present in an athlete's blood. To achieve this goal, it is necessary to differentiate HBOCs from the native hemoglobin and to do so in a cost and time effective manner. We have developed a rapid capillary zone electrophoresis (CZE), UV absorbance, method capable of detecting HBOCs, in whole blood samples, at levels below those considered necessary to provide a performance enhancement. Our approach to the analysis for HBOCs utilizes the whole blood sample, not just the plasma, and does not require the use of immunoprecipitants to ensure accurate analysis. By lysing the red blood cells and using centrifugal filtration, followed by our CZE separation, we are able to effectively distinguish between native hemoglobin and HBOCs. Through this method, we have been able to reliably detect concentrations of HBOCs at the equivalent of 5.5 g/L, the equivalent to a 3.5% increase in blood hemoglobin concentration for an athlete.


Assuntos
Dopagem Esportivo , Eletroforese Capilar/métodos , Hemoglobinas/química , Substâncias para Melhoria do Desempenho/química , Haptoglobinas/análise , Haptoglobinas/química , Hemoglobinas/análise , Humanos , Limite de Detecção , Substâncias para Melhoria do Desempenho/sangue
8.
Int J Sport Nutr Exerc Metab ; 22(6): 479-85, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22899810

RESUMO

PURPOSE: To investigate the effects of polysaccharide from Gynostemma pentaphyllum on antioxidant activity in skeletal muscle of mice exercised to exhaustion. METHODS: Three polysaccharide fractions were obtained from G. pentaphyllum polysaccharide (GPP) and termed GPP1-a, GPP2-b, and GPP3-a. Gas chromatography (GC) and infrared spectrum of the polysaccharides were determined. The fractions were orally administrated to mice once daily for 1 wk. The exercise time to exhaustion was assessed using a forced swim test of mice after a week. The glucose, creatine phosphokinase, and lactic dehydrogenase in serum; the activity of superoxide dismutase and glutathione peroxidase; and the levels of malondialdehyde (MDA) and glycogen in muscle were determined. RESULTS: The results of GC demonstrated that GPP1-a, GPP2-b, and GPP3-a were composed of different monosaccharides with distinct molar ratios. Infrared spectrum showed that the main typicals of GPP1-a and GPP2-b were ß-configuration and the main typical of GPP3-a was α-configuration. Among the 3 fractions of GPP, GPP1-a administration significantly prolonged exercise time to exhaustion of mice, increased glycogen level and some of antioxidant enzyme activities, and decreased MDA level in muscle. CONCLUSIONS: The mechanism by which GPP1-a prolonged exercise time to exhaustion in mice may be associated with scavenging reactive oxygen species excessively produced and further increasing glycogen levels in skeletal muscle.


Assuntos
Antioxidantes/uso terapêutico , Suplementos Nutricionais , Fadiga/prevenção & controle , Gynostemma/química , Músculo Esquelético/metabolismo , Extratos Vegetais/uso terapêutico , Polissacarídeos/uso terapêutico , Animais , Animais não Endogâmicos , Antioxidantes/administração & dosagem , Antioxidantes/química , Antioxidantes/metabolismo , Configuração de Carboidratos , Creatina Quinase/antagonistas & inibidores , Creatina Quinase/sangue , Etnobotânica , Fadiga/sangue , Fadiga/metabolismo , Glicogênio/metabolismo , Lactato Desidrogenases/antagonistas & inibidores , Lactato Desidrogenases/sangue , Peroxidação de Lipídeos , Masculino , Medicina Tradicional Chinesa , Camundongos , Substâncias para Melhoria do Desempenho/administração & dosagem , Substâncias para Melhoria do Desempenho/química , Substâncias para Melhoria do Desempenho/metabolismo , Substâncias para Melhoria do Desempenho/uso terapêutico , Esforço Físico , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Polissacarídeos/administração & dosagem , Polissacarídeos/química , Polissacarídeos/metabolismo , Distribuição Aleatória , Natação
9.
J Sci Food Agric ; 92(4): 736-42, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21953402

RESUMO

BACKGROUND: Seabuckthorn (SBT) leaves have significant antioxidant, immunomodulatory and anti-inflammatory properties. The objective of this study was to assess the anti-fatigue, antioxidant and tissue-protective properties of aqueous lyophilised extracts of SBT dried leaves in the hearts of Wistar male rats undergoing exhaustive physical exercise. Doses of 50, 200 and 800 mg kg⁻¹ body weight (BW) day⁻¹ were given orally for 1 week. A week later the rats were forced to swim in barrels until they were exhausted. The times were noted to establish the effective dose of the extracts in rats. After establishing the effective dose, the rats were then sacrificed and assessed for various biochemical parameters. RESULTS: SBT leaf aqueous extracts (200 and 800 mg kg⁻¹ BW) markedly prolonged the swim time of rats. Supplementation with SBT leaf aqueous extracts helped reduce the exhaustive exercise-induced increase in malondialdehyde level and selenium-dependent glutathione peroxidase activity. Alanine aminotransferase and creatine kinase levels were lowered in the exhaustive exercise with SBT treatment group (E + SBT) compared with the exhaustive exercise group (E). CONCLUSION: The findings suggest that SBT leaf aqueous extract supplements can enhance exercise capacity and protect against oxidative damage caused by exhaustive exercise in rats.


Assuntos
Antioxidantes/uso terapêutico , Fadiga/prevenção & controle , Hippophae/química , Estresse Oxidativo , Substâncias para Melhoria do Desempenho/uso terapêutico , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Suplementos Nutricionais , Tolerância ao Exercício , Fadiga/enzimologia , Fadiga/metabolismo , Masculino , Miocárdio/enzimologia , Miocárdio/metabolismo , Oxirredutases/metabolismo , Substâncias para Melhoria do Desempenho/administração & dosagem , Substâncias para Melhoria do Desempenho/química , Resistência Física , Fitoterapia , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Distribuição Aleatória , Ratos , Ratos Wistar , Natação
10.
Anal Bioanal Chem ; 401(2): 543-51, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21116611

RESUMO

Benfluorex [1-(m-trifluoromethylphenyl)-2-(ß-benzoyloxyethyl)aminopropane] has been widely used for the treatment of atherogenic metabolic disorders and impaired carbohydrate metabolism (particularly in obese type-II diabetic patients) as well as an anorectic drug. Due to its potentially performance-enhancing properties, benfluorex has been added to the list of prohibited compounds and methods of doping by the World Anti-Doping Agency (WADA) in 2010, necessitating the implementation of the drug as well as its major metabolites into routine doping control procedures. In the present study, human urinary metabolites of benfluorex were characterized by gas chromatography-electron ionization-mass spectrometry (GC-EI-MS) as well as liquid chromatography-electrospray ionization-high resolution/high accuracy tandem mass spectrometry (LC-ESI-MS/MS). Commonly employed sports drug testing approaches consisting of liquid-liquid extraction followed by GC-MS or urine dilution and immediate LC-MS/MS analysis were expanded and validated with regard to specificity, recovery (48-54%, GC-MS only), intra- and interday precision (<25%), limits of detection (5-8 ng/mL for LC-MS/MS and 80 ng/mL for GC-MS), and ion suppression (for LC-ESI-MS/MS only) to allow the detection of benfluorex metabolites 1-(m-trifluoromethylphenyl)-2-(2-hydroxyethyl)aminopropane (M1), 1-(m-trifluoromethylphenyl)-2-(2-carboxymethyl)aminopropane (M2), and 1-(m-trifluoromethylphenyl)-2-aminopropane (M3) as well as the glucuronic acid conjugate of M1.


Assuntos
Dopagem Esportivo , Fenfluramina/análogos & derivados , Substâncias para Melhoria do Desempenho/metabolismo , Substâncias para Melhoria do Desempenho/urina , Detecção do Abuso de Substâncias/métodos , Cromatografia Líquida , Fenfluramina/química , Fenfluramina/metabolismo , Fenfluramina/urina , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Substâncias para Melhoria do Desempenho/química , Padrões de Referência , Sensibilidade e Especificidade , Detecção do Abuso de Substâncias/normas , Espectrometria de Massas em Tandem
11.
Anal Bioanal Chem ; 401(2): 529-41, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21380606

RESUMO

In the present study, toremifene urinary excretion studies were evaluated in order to examine main metabolic reactions and to select target metabolites in doping control analysis. Urine samples from three female subjects were collected every 3 h for at least 15 days after the oral administration of a single dose of Fareston® (60 mg). The elemental compositions of the compounds detected were determined by liquid chromatography-mass spectrometry using a time-of-flight system with accurate mass measurement. More detailed structure elucidation was obtained by monitoring the presence or absence of structure-specific ions, using product ion scan and neutral loss acquisition modes, whereas the metabolites urinary profiles were evaluated in selected reaction monitoring acquisition mode. The results showed that the main routes of phase-I modifications involved carboxylation of the chlorinated side chain, N-demethylation and hydroxylation in different positions. Fifteen metabolites were found in all subjects studied, most of them were detected for more than 10 days in the free, glucuronide and sulphate fractions, with a maximum of excretion generally after 9-22 and 34-47 h from drug administration. These metabolites can be divided in two groups: metabolites with the characteristic chlorine isotope pattern and metabolites without the characteristic chlorine isotope pattern. The most abundant and long-term compounds were the carboxylated metabolites followed by the hydroxylated metabolites. Their product ions originating after collision-induced dissociation were observed to occur prevalently in the dimethylaminoethoxy and in the chlorinated side chains. These structure-specific ions were used to design screening and confirmation procedures to positively identify toremifene administration in doping control analysis.


Assuntos
Dopagem Esportivo , Substâncias para Melhoria do Desempenho/metabolismo , Substâncias para Melhoria do Desempenho/urina , Detecção do Abuso de Substâncias/métodos , Toremifeno/metabolismo , Toremifeno/urina , Adulto , Cromatografia Líquida , Feminino , Humanos , Espectrometria de Massas , Substâncias para Melhoria do Desempenho/química , Valores de Referência , Sensibilidade e Especificidade , Toremifeno/química
12.
Biomed Chromatogr ; 25(1-2): 147-54, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21204111

RESUMO

A sensitive method using LC/ESI-MS(n) has been developed on a quadrupole linear ion trap mass analyser for the detection of nine ß(2) agonists (cimaterol, clenbuterol, fenoterol, formoterol, mabuterol, terbutaline, ractopamine, salbutamol and salmeterol) in horse urine. The method consists of solid-phase extraction on CSDAU cartridges before analysis by LC/ESI-MS(n) . The efficiency of extraction combined with the sensitivity and the selectivity of MS(n) allowed the detection of these compounds at pg/mL levels. Administration studies of fenoterol and formoterol are reported and show their possible detection after inhalation. The method is applicable for screening and confirmatory analysis.


Assuntos
Agonistas Adrenérgicos beta/urina , Cromatografia Líquida de Alta Pressão/métodos , Dopagem Esportivo/prevenção & controle , Etanolaminas/urina , Cavalos/urina , Substâncias para Melhoria do Desempenho/urina , Espectrometria de Massas por Ionização por Electrospray/métodos , Agonistas Adrenérgicos beta/química , Animais , Etanolaminas/química , Substâncias para Melhoria do Desempenho/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
PLoS One ; 16(7): e0248456, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34197456

RESUMO

The timing of sodium bicarbonate (NaHCO3) supplementation has been suggested to be most optimal when coincided with a personal time that bicarbonate (HCO3-) or pH peaks in the blood following ingestion. However, the ergogenic mechanisms supporting this ingestion strategy are strongly contested. It is therefore plausible that NaHCO3 may be ergogenic by causing beneficial shifts in the strong ion difference (SID), though the time course of this blood acid base balance variable is yet to be investigated. Twelve highly trained, adolescent swimmers (age: 15.9 ± 1.0 years, body mass: 65.3 ± 9.6 kg) consumed their typical pre-competition nutrition 1-3 hours before ingesting 0.3 g∙kg BM-1 NaHCO3 in gelatine capsules. Capillary blood samples were then taken during seated rest on nine occasions (0, 60, 75, 90, 105, 120, 135, 150, 165 min post-ingestion) to identify the time course changes in HCO3-, pH, and the SID. No significant differences were found in the time to peak of each blood measure (HCO3-: 130 ± 35 min, pH: 120 ± 38 min, SID: 98 ± 37 min; p = 0.08); however, a large effect size was calculated between time to peak HCO3- and the SID (g = 0.88). Considering that a difference between time to peak blood HCO3- and the SID was identified in adolescents, future research should compare the ergogenic effects of these two individualized NaHCO3 ingestion strategies compared to a traditional, standardized approach.


Assuntos
Equilíbrio Ácido-Base/fisiologia , Atletas , Bicarbonatos/sangue , Bicarbonato de Sódio/administração & dosagem , Adolescente , Eructação/etiologia , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Náusea/etiologia , Substâncias para Melhoria do Desempenho/administração & dosagem , Substâncias para Melhoria do Desempenho/efeitos adversos , Substâncias para Melhoria do Desempenho/química , Bicarbonato de Sódio/efeitos adversos , Bicarbonato de Sódio/química , Natação
14.
Drug Test Anal ; 13(2): 261-267, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33369180

RESUMO

Higenamine was included in the World Anti-Doping Agency (WADA) Prohibited Substances and Methods List as a ß2 -adrenoceptor agonist in 2017, thereby resulting in its prohibition both in and out of competition. The present mini review describes the physiology and pharmacology of adrenoceptors, summarizes the literature addressing the mechanism of action of higenamine and extends these findings with previously unpublished in silico and in vitro work. Studies conducted in isolated in vitro systems, whole-animal preparations and a small number of clinical studies suggest that higenamine acts in part as a ß2 -adrenoceptor agonist. In silico predictive tools indicated that higenamine and possibly a metabolite have a high probability of interacting with the ß2 -receptor as an agonist. Stable expression of human ß2 -receptors in Chinese hamster ovary (CHO) cells to measure agonist activity not only confirmed the activity of higenamine at ß2 but also closely agreed with the in silico prediction of potency for this compound. These data confirm and extend literature findings supporting the inclusion of higenamine in the Prohibited List.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Alcaloides/farmacologia , Substâncias para Melhoria do Desempenho/farmacologia , Receptores Adrenérgicos beta 2/metabolismo , Tetra-Hidroisoquinolinas/farmacologia , Agonistas Adrenérgicos beta/química , Alcaloides/química , Animais , Desempenho Atlético , Dopagem Esportivo , Humanos , Substâncias para Melhoria do Desempenho/química , Tetra-Hidroisoquinolinas/química
15.
Med Hypotheses ; 131: 109301, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31443771

RESUMO

Caffeine is a well-established ergogenic aid, with its performance-enhancing effects replicated across a variety of exercise types. Caffeine exerts its performance-benefits through many mechanisms, including acting as an adenosine receptor antagonist, and serving to reduce sensations of fatigue and pain. One potential mechanism that is currently underexplored is whether caffeine's bitter taste mediates some of its ergogenic effects, which is discussed in this article. Previous research has demonstrated that bitter tastants have the ability to enhance performance, and this effect is mediated by bitter taste receptors in the mouth and gastrointestinal tract. Additionally, the ability to detect bitter tastes is subject to individual variation, raising the potential that the demonstrated inter-individual response to a standardised caffeine dose is potentially driven by differences in taste response. Finally, it appears that some of caffeine's performance-enhancing effects are driven by expectancy. As bitter taste may serve as a signal that caffeine has been ingested, it is possible that some of the expectancy effects of caffeine ingestion are driven by its bitter taste. These aspects all have potentially important implications for future research, as well as for how athletes and coaches utilise caffeine around competition, both of which are explored in depth here.


Assuntos
Cafeína/farmacologia , Modelos Biológicos , Substâncias para Melhoria do Desempenho/farmacologia , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Paladar , Antecipação Psicológica , Desempenho Atlético , Variação Biológica Individual , Cafeína/administração & dosagem , Cafeína/química , Carboidratos/administração & dosagem , Carboidratos/farmacologia , Condicionamento Psicológico , Sinais (Psicologia) , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/fisiologia , Humanos , Modelos Psicológicos , Antissépticos Bucais , Substâncias para Melhoria do Desempenho/química , Receptores Acoplados a Proteínas G/fisiologia , Percepção Gustatória/genética
16.
Aliment Pharmacol Ther ; 49(9): 1195-1204, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30934130

RESUMO

BACKGROUND: Bodybuilding supplements can cause a profound cholestatic syndrome. AIM: To describe the drug-Induced liver injury network's experience with liver injury due to bodybuilding supplements. METHODS: Liver injury pattern, severity and outcomes, potential genetic associations, and exposure to anabolic steroids by product analysis were analysed in prospectively enrolled subjects with bodybuilding supplement-induced liver injury with causality scores of probable or higher. RESULTS: Forty-four males (mean age 33 years) developed liver injury with a median latency of 73 days. Forty-one per cent presented with hepatocellular pattern of liver injury as defined by the R > 5 ([Fold elevation of ALT] ÷ [Fold elevation of Alk Phos] (mean, range = 6.4, 0.5-31.4, n = 42) despite all presenting with clinical features of cholestatic liver injury (100% with jaundice and 84% with pruritus). Liver biopsy (59% of subjects) demonstrated a mild hepatitis and profound cholestasis in most without bile duct injury, loss or fibrosis. Seventy-one per cent were hospitalised, and none died or required liver transplantation. In some, chemical analysis revealed anabolic steroid controlled substances not listed on the label. No enrichment of genetic variants associated with cholestatic syndromes was found, although mutations in ABCB11 (present in up to 20%) were significantly different than in ethnically matched controls. CONCLUSIONS: Patients with bodybuilding supplements liver injury uniformly presented with cholestatic injury, which slowly resolved. The ingested products often contained anabolic steroids not identified on the label, and no enrichment in genetic variants was found, indicating a need for additional studies.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Colestase/induzido quimicamente , Suplementos Nutricionais/efeitos adversos , Músculos , Substâncias para Melhoria do Desempenho/efeitos adversos , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Adulto , Biópsia , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/patologia , Colestase/epidemiologia , Colestase/genética , Colestase/terapia , Suplementos Nutricionais/análise , Predisposição Genética para Doença/epidemiologia , Humanos , Transplante de Fígado/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Músculos/efeitos dos fármacos , Músculos/patologia , Substâncias para Melhoria do Desempenho/análise , Substâncias para Melhoria do Desempenho/química , Fatores de Risco , Índice de Gravidade de Doença , Somatotipos/fisiologia , Adulto Jovem
18.
Drug Test Anal ; 10(1): 9-27, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29149502

RESUMO

Several high-profile revelations concerning anti-doping rule violations over the past 12 months have outlined the importance of tackling prevailing challenges and reducing the limitations of the current anti-doping system. At this time, the necessity to enhance, expand, and improve analytical test methods in response to the substances outlined in the World Anti-Doping Agency's (WADA) Prohibited List represents an increasingly crucial task for modern sports drug-testing programs. The ability to improve analytical testing methods often relies on the expedient application of novel information regarding superior target analytes for sports drug-testing assays, drug elimination profiles, alternative test matrices, together with recent advances in instrumental developments. This annual banned-substance review evaluates literature published between October 2016 and September 2017 offering an in-depth evaluation of developments in these arenas and their potential application to substances reported in WADA's 2017 Prohibited List.


Assuntos
Dopagem Esportivo/prevenção & controle , Substâncias para Melhoria do Desempenho/análise , Substâncias para Melhoria do Desempenho/química , Detecção do Abuso de Substâncias/métodos , Dopagem Esportivo/legislação & jurisprudência , Humanos , Substâncias para Melhoria do Desempenho/sangue , Detecção do Abuso de Substâncias/legislação & jurisprudência
19.
J Pharm Biomed Anal ; 151: 347-355, 2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29413984

RESUMO

Phenethylamines (PEAs) are popular substances found in weight-loss and sports nutrition supplements. They are generally pharmacologically active and primarily affect the sympathetic nervous system. Many PEAs are synthetic chemicals and are on the prohibited list of the World Anti-Doping Agency. In this study, nuclear magnetic resonance (NMR) spectroscopy was applied to detect and identify the presence of PEAs in sports dietary supplements without the need for chromatographic separation or pre-knowledge on formulation. Eight PEAs, viz. phenethylamine, synephrine, oxilofrine, hordenine, ß-methylphenethylamine, N-methyltyramine, octopamine and deterenol, were identified from 32 dietary supplements sold in the US market. Furthermore, a quantitative NMR method was developed and validated for simultaneous determination of the concentrations of the PEAs. The study demonstrated that NMR could be a potential tool to monitor and detect PEAs or other ingredients in dietary supplements.


Assuntos
Diosgenina/análise , Dopagem Esportivo/prevenção & controle , Substâncias para Melhoria do Desempenho/análise , Fenetilaminas/análise , Fitosteróis/análise , Espectroscopia de Prótons por Ressonância Magnética/métodos , Deutério/química , Diosgenina/química , Humanos , Substâncias para Melhoria do Desempenho/química , Fenetilaminas/química , Fitosteróis/química , Espectroscopia de Prótons por Ressonância Magnética/instrumentação , Coloração e Rotulagem/métodos
20.
Nutrients ; 10(12)2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30544515

RESUMO

Essence of chicken is a popular Asian nutritional supplement that is often taken to improve metabolism and general health. Although used as a traditional remedy for combating fatigue and general health, there has been few studies investigating the ergogenic properties of chicken essence and its associated mechanism. We conducted a study to investigate the anti-fatigue and anti-oxidant properties of essence of chicken (EC) after exercise. Six weeks old male Institute of Cancer Research (ICR) mice were divided to four groups (10 mice/group) and were provided different doses of Essence of Chicken (EC): (1) Vehicle (water), (2) EC-0.5X (558 mg/kg), (3) EC-1X (1117 mg/kg), and (4) EC-2X (2234 mg/kg). EC supplementation could improve endurance and grip strength (p < 0.0001) and it had significant effects on the fatigue-related biochemical markers: ammonia, blood urea nitrogen (BUN), and creatine kinase (CK) levels were significantly lowered, while glucose blood levels and lactate clearance were improved after exercise challenge. Muscle and liver glycogen levels, muscle and liver superoxide dismutase (SOD), hepatic catalase (CAT), and glutathione (GSH) levels were observed to increase with EC supplementation. Preliminary in vitro data suggests that EC may have a beneficial effect in muscle mass and strength. No abnormalities were observed from pathohistological examination. Our study suggests that the EC could significantly improve exercise performance and endurance capacity and that the anti-oxidant properties of EC may be an important contributing factor to its anti-fatigue effects.


Assuntos
Galinhas , Força Muscular/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/farmacologia , Resistência Física/efeitos dos fármacos , Produtos Avícolas , Animais , Antioxidantes/química , Antioxidantes/farmacologia , Peso Corporal/efeitos dos fármacos , Linhagem Celular , Ingestão de Alimentos/efeitos dos fármacos , Masculino , Medicina Tradicional Chinesa , Camundongos , Camundongos Endogâmicos ICR , Estresse Oxidativo/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/química , Natação
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