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1.
Clin Endocrinol (Oxf) ; 101(1): 42-50, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38446525

RESUMEN

OBJECTIVE: Human choriogonadotrophin (hCG) treatment of gonadotrophin-deficient infertile men uses hCG of urinary (uhCG) or recombinant (rhCG) origin, but these treatments have not been compared nor are there studies defining rhCG dosing in men. DESIGN: hCG products were studied in randomized cross-over single-dose studies of standard (Study 1, 1500 IU and 62.5 µg, respectively) or high (Study 2, 5000 IU and 250 µg) dose and a multi-dose population pharmacology study of hCG use. PARTICIPANTS: Eight (Study 1) and seven (Study 2) volunteers in cross-over and 52 gonadotrophin-deficient men in the multi-dose study MEASUREMENTS: In cross-over studies, serum testosterone (T), dihydrotestosterone (DHT) and estradiol by liquid chromatography-mass spectrometry (LCMS) and serum hCG, LH, FSH, SHBG and T (observational study) by immunoassays. RESULTS: After standard and high-dose injection, serum hCG and testosterone responses had similar timing and peak concentrations except for a mildly lower early (<48 h) serum testosterone with uhCG. In the multi-dosing study, both hCGs had similar pharmacokinetics (pooled half-life 5.8 days, p < .001), while serum testosterone concentrations were stable after injection and did not differ between hCG products. Bench testing verified that 20% of pens from 4/10 individuals were used inappropriately. CONCLUSIONS: Although hCG pharmacokinetics are not formally bioequivalent, the similar pharmacodynamic effects on serum testosterone indicate that at the doses tested both hCGs provide comparable clinical effects. The starting dose of rhCG for treating gonadotrophin-deficient men should be 62.5 µg (6 clicks) of the rhCG pen.


Asunto(s)
Gonadotropina Coriónica , Estudios Cruzados , Proteínas Recombinantes , Testosterona , Humanos , Masculino , Gonadotropina Coriónica/administración & dosificación , Gonadotropina Coriónica/orina , Testosterona/sangre , Testosterona/administración & dosificación , Testosterona/orina , Adulto , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacocinética , Hormona Luteinizante/sangre , Hormona Luteinizante/orina , Dihidrotestosterona/sangre , Dihidrotestosterona/orina , Estradiol/sangre , Relación Dosis-Respuesta a Droga , Hormona Folículo Estimulante/sangre , Hormona Folículo Estimulante/orina , Adulto Joven , Persona de Mediana Edad , Infertilidad Masculina/tratamiento farmacológico , Infertilidad Masculina/orina , Infertilidad Masculina/sangre , Globulina de Unión a Hormona Sexual/análisis
2.
Drug Test Anal ; 2024 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-38342098

RESUMEN

Nandrolone and its prohormones, including 19-norandrost-4-ene-3,17-dione and 19-norandrost-4-ene-3ß,17ß-diol, are anabolic steroids forbidden at all times in sports according to the World Anti-Doping Code Prohibited List and its metabolite 19-norandrosterone (19NA) is the preferred urinary target compound to identify their abuse. In recent years, an increasing number of 19NA isotope ratio mass spectrometry (IRMS) cases have arisen that, based on the initial testing procedure, were likely to result in an adverse analytical finding but were concluded negative after IRMS analysis. The current study was therefore set up to gain a better insight on the prevalence of nandrolone preparations with endogenous carbon isotope ratio values in Australia. Suitable workplace (non-athlete) urine samples that had previously been reported positive for 19NA were identified and analysed on IRMS. A total of 82% of the samples that were analysed were reported with enriched carbon isotope ratios of 19NA (i.e., 19NA greater than -26‰). This indicates that there is a high prevalence of nandrolone-containing anabolic androgenic steroid preparations in Australia that have 'endogenous' carbon isotope ratios which reduces the ability to identify exogenous nandrolone.

3.
J Am Soc Mass Spectrom ; 28(8): 1657-1665, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28425052

RESUMEN

The mobile phase additive (DMSO) has been described as a useful tool to enhance electrospray ionization (ESI) of peptides and proteins. So far, this technique has mainly been used in proteomic/peptide research, and its applicability in a routine clinical laboratory setting (i.e., doping control analysis) has not been described yet. This work provides a simple, easy to implement screening method for the detection of doping relevant small peptides (GHRPs, GnRHs, GHS, and vasopressin-analogues) with molecular weight less than 2 kDa applying DMSO in the mobile phase. The gain in sensitivity was sufficient to inject the urine samples after a 2-fold dilution step omitting a time consuming sample preparation. The employed analytical procedure was validated for the qualitative determination of 36 compounds, including 13 metabolites. The detection limits (LODs) ranged between 50 and 1000 pg/mL and were compliant with the 2 ng/mL minimum detection level required by the World Anti-Doping Agency (WADA) for all the target peptides. To demonstrate the feasibility of the work, urine samples obtained from patients who have been treated with desmopressin or leuprolide and urine samples that have been declared as adverse analytical findings were analyzed. Graphical Abstract ᅟ.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Dimetilsulfóxido/química , Hormonas Peptídicas/orina , Espectrometría de Masa por Ionización de Electrospray/métodos , Detección de Abuso de Sustancias/métodos , Cromatografía Liquida/métodos , Doping en los Deportes , Humanos , Límite de Detección , Espectrometría de Masas en Tándem/métodos
4.
J Steroid Biochem Mol Biol ; 141: 113-20, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24495617

RESUMEN

Non-steroidal drugs that increase endogenous testosterone (T) may be used to exploit ergogenic effects of androgens in power sports. While superactive GnRH analog use is suspected, neither screening nor detection tests are developed. This study aimed to determine if (a) stimulation for 5 days by leuprolide (a superactive GnRH analog) of serum and urine steroids and urine LH is reproducible at a 2 week interval, (b) nandrolone decanoate (ND) co-administration masks responses to leuprolide administration, (c) performance of urine measurement of leuprolide and M1, its major metabolite, as a detection test. Healthy men were randomized into a 4 week parallel group, open label clinical study in which all men had daily sc injections of leuprolide (1mg) for 4 days in the 1st and 3rd weeks with hormone-free 2nd and 4th weeks. In the 3rd week, men were randomized to either ND injections or no extra treatment. Serum steroids were determined by liquid chromatography, tandem mass spectrometry (LC-MS), urine steroids by gas chromatography, mass spectrometry (GC-MS), urine leuprolide and M1 by high resolution LC-MS and urine LH by immunoassay. Leuprolide stimulated striking, reproducible increases in serum and urine LH and steroids (serum T, dihydroT (DHT), 3α diol; urine T, epitestosterone (E) and androsterone (A). ND suppressed basal serum T, E2, 3α diol, and urinary E but did not mask or change the magnitude of responses to leuprolide. Urine leuprolide and M1 measurement had 100% sensitivity and specificity in detecting leuprolide administration up to one day after cessation of injections with the detection window between 1 and 3 days after last dose. Screening using urine steroid and LH measurements, optimally by urinary log10(LHxT), correctly classified 82% of urine samples. It is concluded that leuprolide stimulation of endogenous testosterone is reproducible after a 10-day interval, is not masked by ND and is reliably detected by urine leuprolide or M1 measurement for at least 1 day after administration.


Asunto(s)
Leuprolida/administración & dosificación , Hormona Luteinizante/sangre , Sustancias para Mejorar el Rendimiento/administración & dosificación , Testosterona/sangre , Adulto , Dihidrotestosterona/sangre , Dihidrotestosterona/orina , Doping en los Deportes , Estradiol/sangre , Estradiol/orina , Humanos , Leuprolida/farmacocinética , Leuprolida/orina , Hormona Luteinizante/orina , Masculino , Persona de Mediana Edad , Nandrolona/análogos & derivados , Nandrolona/farmacología , Nandrolona Decanoato , Sustancias para Mejorar el Rendimiento/farmacocinética , Sustancias para Mejorar el Rendimiento/orina , Testosterona/orina , Adulto Joven
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