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1.
Drug Test Anal ; 12(11-12): 1614-1619, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32809277

RESUMO

Early in 2020, racehorse doping cases revolved around the hypoxia-inducible factor (HIF) activator IOX-2. While the composition of IOX-2 has also been known and monitored in human doping controls for several years, the testing capability of routine sports drug testing methods was revisited for this newly surfaced doping agent. IOX-2 and the analytically well-established HIF activator roxadustat (FG-4592) share identical precursor/product ion pairs, enabling their co-detection in existing initial testing procedures in routine doping controls for the intact unconjugated analytes. In addition, hydroxylated IOX-2 and the corresponding glucuronic acid conjugates were identified as major metabolites in a microdose elimination study, contributing to enhanced initial testing and confirmation procedures.


Assuntos
Dopagem Esportivo/prevenção & controle , Fator 1 Induzível por Hipóxia/agonistas , Fator 1 Induzível por Hipóxia/metabolismo , Prolina Dioxigenases do Fator Induzível por Hipóxia/urina , Isoquinolinas/urina , Detecção do Abuso de Substâncias/normas , Dopagem Esportivo/métodos , Glicina/administração & dosagem , Glicina/análogos & derivados , Glicina/urina , Humanos , Prolina Dioxigenases do Fator Induzível por Hipóxia/administração & dosagem , Isoquinolinas/administração & dosagem , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Retrospectivos , Detecção do Abuso de Substâncias/métodos
3.
J Pediatr Endocrinol Metab ; 30(7): 749-757, 2017 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-28672749

RESUMO

BACKGROUND: While the main role of growth hormone (GH) replacement therapy in children is to promote linear growth, GH has also an effect on lipids and body composition. There is an ongoing discussion whether discontinuation of GH treatment is associated with deterioration of lipids. METHODS: We analyzed weight status [as body mass index-standard deviation score (BMI-SDS)], insulin like growth factor (IGF)-1, triglycerides, total, low-density liporptoein (LDL)- and high-density lipoprotein (HDL)-cholesterol at the end of GH treatment and in mean 6 months later in 90 adolescents (53 with GH deficiency, 16 with Turner syndrome [TS] and 21 born small-for-gestational age [SGA]). RESULTS: After stopping GH treatment, total cholesterol (+10±24 mg/dL vs. -4±13 mg/dL) and LDL-cholesterol (+15±20 mg/dL vs. -6±12 mg/dL) increased significantly higher in severe (defined by GH peak in stimulation test <3 ng/mL) compared to moderate GHD. In patients with TS, total cholesterol (+19±9 mg/dL), LDL-cholesterol (+9±12 mg/dL) and HDL-cholesterol (+4.3±3.5 mg/dL) increased significantly. In adolescents born SGA, triglycerides increased (+34±51 mg/dL) and HDL-cholesterol decreased significantly (-3.8±7.1 mg/dL). In multiple linear regression analyses, changes of total and LDL-cholesterol were significantly negatively related to peak GH in stimulation tests, but not to gender, age at GH start, duration of GH treatment, observation time, changes of BMI-SDS or IGF-1 after the end of GH treatment. The BMI-SDS did not change after the end of GH treatment. CONCLUSIONS: Discontinuation of GH treatment leads to a deterioration of lipids in TS, SGA and severe but not moderate GHD.


Assuntos
Índice de Massa Corporal , Peso Corporal/efeitos dos fármacos , Transtornos do Crescimento/fisiopatologia , Hormônio do Crescimento Humano/administração & dosagem , Recém-Nascido Pequeno para a Idade Gestacional/crescimento & desenvolvimento , Lipídeos/análise , Síndrome de Turner/fisiopatologia , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/deficiência , Humanos , Lactente , Recém-Nascido , Masculino , Prognóstico , Fatores de Risco , Triglicerídeos/metabolismo , Síndrome de Turner/tratamento farmacológico
4.
Clin Endocrinol (Oxf) ; 87(2): 185-193, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28432801

RESUMO

OBJECTIVE: The Anti-Muellerian Hormone (AMH) has been reported as surrogate marker of antral follicles, which are the origins of hyperandrogenism in polycystic ovarian syndrome (PCOS). Therefore, AMH may be useful for the diagnosis of PCOS. The objective was to study the longitudinal changes in AMH concentrations in girls with and without PCOS. DESIGN: This is a longitudinal study of obese girls participating in a 1-year lifestyle intervention. PATIENTS: Forty obese girls aged 13-16 years (50% with PCOS) were included in the study. Girls with and without PCOS were matched to age, BMI and change in weight status. MEASUREMENTS: AMH, gonadotropins, androstenedione, testosterone, oestradiol and sex hormone-binding globulin (SHBG) were determined. RESULTS: Obese girls with PCOS demonstrated significantly (P<.001) higher AMH concentrations (5.8±3.1 ng/mL) compared to obese girls without PCOS (2.4±1.4 ng/mL). None of the girls without PCOS had AMH concentrations ≥6 ng/mL and none of the PCOS girls showed AMH concentrations ≤3 ng/mL. Weight loss in girls with PCOS was associated with a significant drop in AMH concentrations (-1.4±1.8 ng/mL, P=.045). AMH was significantly related to testosterone (cross-sectional: b-coefficient 3.7±1.7, P=.001, longitudinal: b-coefficient 0.54±0.47, P=.026) and luteinizing hormone (LH) (cross-sectional: b-coefficient 0.05±0.04, P=.039, longitudinal: b-coefficient 0.005±0.004, P=.039), but not to any other analysed parameter in multiple linear regression analyses adjusted to multiple confounders. CONCLUSIONS: AMH was increased in adolescent girls with PCOS and normalized with weight loss. AMH was cross-sectionally and longitudinally related to hyperandrogenism.


Assuntos
Hormônio Antimülleriano/sangue , Obesidade , Síndrome do Ovário Policístico/complicações , Redução de Peso/fisiologia , Adolescente , Estudos Transversais , Feminino , Humanos , Hiperandrogenismo/sangue , Estudos Longitudinais , Hormônio Luteinizante , Testosterona
5.
Endocr Connect ; 6(4): 213-224, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28373267

RESUMO

OBJECTIVE: The underlying mechanisms of polycystic ovarian syndrome (PCOS) are not fully understood yet. The aim of the study was to get functional insights into the regulation of steroid hormones in PCOS by steroid metabolomics. DESIGN: This is a longitudinal study of changes of steroid hormones in 40 obese girls aged 13-16 years (50% with PCOS) participating in a 1-year lifestyle intervention. Girls with and without PCOS were matched to age, BMI and change of weight status. METHODS: We measured progesterone, 17-hydroxyprogesterone, 17-hydroxyprogenolon, 11-deoxycorticosterone, 21-deoxycorticosterone, deoxycorticosterone, corticosterone, 11-deoxycortisol, cortisol, cortisone, androstenedione, testosterone, dehydroepiandrostendione-sulfate (DHEA-S), estrone and estradiol by LC-MS/MS steroid profiling at baseline and one year later. RESULTS: At baseline, obese PCOS girls demonstrated significantly higher androstenedione and testosterone concentrations compared to obese girls without PCOS, whereas the other steroid hormones including glucocorticoids, mineralocorticoids, estrogens and precursors of androgens did not differ significantly. Weight loss in obese PCOS girls was associated with a significant decrease of testosterone, androstenedione, DHEA-S, cortisol and corticosterone concentrations. Weight loss in obese non-PCOS girls was associated with a significant decrease of DHEA-S, cortisol and corticosterone concentrations, whereas no significant changes of testosterone and androstenedione concentrations could be observed. Without weight loss, no significant changes of steroid hormones were measured except an increase of estradiol in obese PCOS girls without weight loss. CONCLUSIONS: The key steroid hormones in obese adolescents with PCOS are androstenedione and testosterone, whereas glucocorticoids, mineralocorticoids, estrogens and precursors of androgens did not differ between obese girls with and without PCOS.

6.
J Pediatr ; 184: 143-150.e1, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28238482

RESUMO

OBJECTIVE: To assess the impact of weight changes on the onset of puberty in overweight children. STUDY DESIGN: We evaluated the timing of puberty onset in 160 prepubertal overweight children (aged 11.2 ± 1.0 years) depending on the changes of their weight status in a 1-year lifestyle intervention. We determined body mass index (BMI), pubertal stage, luteinizing hormone (LH), follicle-stimulating hormone, insulin-like growth factor (IGF)-1, insulin-like growth factor binding protein-3, insulin resistance index homeostatic model assessment, and serum gonadotropins at baseline and 1 year later. RESULTS: Puberty onset during the 1-year follow-up was significantly (P = .014) more frequent in girls without BMI-SDS reduction (75.0%) compared with girls with BMI-SDS reduction (45.7%). The start of puberty was significantly (P = .024) more frequent in boys with BMI-SDS reduction (76.9%) compared with boys without BMI-SDS reduction (53.6%). In logistic regression analyses adjusted for baseline age and BMI-SDS, BMI-SDS reduction was associated with a decreased likelihood for puberty onset in girls (OR 0.24; 95% CI 0.07-0.85) and an increased likelihood in boys (OR 3.77; 95% CI 1.34-10.52). Central onset of puberty was confirmed by an increase of LH concentration and LH/follicle-stimulating hormone ratio in both boys and girls. Homeostatic model assessment, IGF-1, and IGF-1/insulin-like growth factor binding protein-3 ratio as marker for free IGF-1 at baseline or their changes were not associated with the onset of puberty. CONCLUSIONS: BMI-SDS reduction in overweight children was associated with earlier gonadotropin-dependent onset of puberty in boys and later onset of puberty in girls, suggesting earlier puberty in obese girls and later puberty in obese boys. We found no evidence that insulin resistance or IGF-1 have an impact on the start of puberty in obese children. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00435734.


Assuntos
Sobrepeso/fisiopatologia , Puberdade , Redução de Peso , Adolescente , Criança , Feminino , Humanos , Masculino , Sobrepeso/sangue , Puberdade/sangue
7.
J Pharm Biomed Anal ; 138: 175-179, 2017 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-28213178

RESUMO

Following a one-year monitoring program providing unequivocal analytical evidence for a high prevalence in international elite sports, meldonium has been included in the World Anti-Doping Agency's (WADA) list of prohibited substances that came into effect on 1 January 2016. Despite of the polar and hydrophilic nature of the molecule, an unusual long detection window was observed in pilot elimination studies. Consequently, in the present study, urinary excretion profiles after single-dose (5 volunteers, 1×500mg) and multiple-dose oral application (5 volunteers; 2×500mg/day for 6days) were determined in order to facilitate the result management concerning meldonium findings in doping controls. Particularly the option to differentiate between recent use and tapering concentrations was studied. Urinary meldonium concentrations were determined using an analytical approach based on hydrophilic interaction liquid chromatography and high resolution tandem mass spectrometry. The study corroborates the hypothesis of a non-linear, dose-depended and biphasic excretion profile after oral application of meldonium and demonstrates that urinary detection windows are of considerable extent with up to 65 and 117days (concentrations>LOQ of 10ng/mL) following single- and multiple-dose applications, respectively.


Assuntos
Líquidos Corporais/química , Metilidrazinas/urina , Adulto , Cromatografia Líquida/métodos , Dopagem Esportivo/métodos , Feminino , Voluntários Saudáveis , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Pessoa de Meia-Idade , Esportes , Detecção do Abuso de Substâncias/métodos , Espectrometria de Massas em Tandem/métodos
8.
Drug Test Anal ; 7(11-12): 1057-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26481102

RESUMO

2-Phenylethanamine (phenethylamine, PEA) represents the core structure of numerous drugs with stimulant-like properties and is explicitly featured as so-called specified substance on the World Anti-Doping Agency (WADA) Prohibited List. Due to its natural occurrence in humans as well as its presence in dietary products, studies concerning the ability of test methods to differentiate between an illicit intake and the renal elimination of endogenously produced PEA were indicated. Following the addition of PEA to the Prohibited List in January 2015, retrospective evaluation of routine doping control data of 10 190 urine samples generated by combined gas chromatography-mass spectrometry and nitrogen phosphorus-specific detection (GC-MS/NPD) was performed. Signals for PEA at approximate concentrations > 500 ng/mL were observed in 31 cases (0.3%), which were subjected to a validated isotope-dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) test method for accurate quantification of the target analyte. Further, using elimination study urine samples collected after a single oral administration of 250 mg of PEA hydrochloride to two healthy male volunteers, two tentatively identified metabolites of PEA were observed and evaluated concerning their utility as discriminative markers for PEA intake. The ID-LC-MS/MS approach was extended to allow for the simultaneous detection of PEA and 2-(3-hydroxyphenyl)acetamide sulfate (M1), and concentration ratios of M1 and PEA were calculated for elimination study urine samples and a total of 205 doping control urine samples that returned findings for PEA at estimated concentrations of 50-2500 ng/mL. Urine samples of the elimination study with PEA yielded concentration ratios of M1/PEA up to values of 9.4. Notably, the urinary concentration of PEA did increase with the intake of PEA only to a modest extent, suggesting a comprehensive metabolism of the orally administered substance. Conversely, doping control urine samples with elevated (>50 ng/mL) amounts of PEA returned quantifiable concentrations of M1 only in 3 cases, which yielded maximum ratios of M1/PEA of 0.9, indicating an origin of PEA other than an orally ingested drug formulation. Consequently, the consideration of analyte abundance ratios (e.g. M1/PEA) is suggested as a means to identify the use of PEA by athletes, but further studies to support potential decisive criteria are warranted.


Assuntos
Acetamidas/urina , Dopagem Esportivo , Substâncias para Melhoria do Desempenho/urina , Fenetilaminas/urina , Detecção do Abuso de Substâncias/métodos , Sulfatos/urina , Calibragem , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Técnicas de Diluição do Indicador , Masculino , Desintoxicação Metabólica Fase II , Valor Preditivo dos Testes , Padrões de Referência , Eliminação Renal , Reprodutibilidade dos Testes , Estudos Retrospectivos , Detecção do Abuso de Substâncias/normas , Espectrometria de Massas em Tandem , Fatores de Tempo , Urinálise
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