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1.
Gen Comp Endocrinol ; 195: 68-79, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-24212051

RESUMEN

Reliable measurements of physiological stress are increasingly needed for eco-physiological research and for species conservation or management. Stress can be estimated by quantifying plasma glucocorticoid levels, but when this is not feasible, glucocorticoid metabolites are often measured from feces (FGCM). However, evidence is accumulating on the sensitivity of FGCM measurements to various nuisance factors. Careful species- and context-specific validations are therefore necessary to confirm the biological relevance and specificity of the method. The goals of this study were to: (1) establish and validate sampling methods and an enzymeimmunoassay to measure FGCM in the gray mouse lemur (Microcebus murinus); (2) explore causes of variability in the FGCM measurements, and; (3) assess the consequences of capturing and handling for free-living individuals by quantifying their stress responses via repeated fecal sampling within capture sessions. We further assessed the influence of different handling protocols and the animals' previous capture experience on the magnitude of the physiological response. Our validations identified the group-specific measurement of 11ß-hydroxyetiocholanolone as the most suitable assay for monitoring adrenocortical activity. The sample water content and the animal's age were found to significantly influence baseline FGCM-levels. Most captured animals exhibited a post-capture FGCM-elevation but its magnitude was not related to the handling protocol or capture experience. We found no evidence for long-term consequences of routine capturing on the animals' stress physiology. Hence the described methods can be employed to measure physiological stress in mouse lemurs in an effective and relatively non-invasive way.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Etiocolanolona/análisis , Heces/química , Glucocorticoides/análisis , Manejo de Especímenes , Estrés Fisiológico , Animales , Cheirogaleidae , Etiocolanolona/metabolismo , Femenino , Glucocorticoides/metabolismo , Masculino , Ratones
2.
Biol Reprod ; 84(2): 288-98, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20944082

RESUMEN

Previous studies of the round goby (Neogobius melanostomus Pallas, 1814), an invasive fish species in the Laurentian Great Lakes of North America, have shown that this species has the ability to both synthesize and smell steroids that have a 5 beta-reduced and 3 alpha-hydroxyl (5 beta,3 alpha) configuration. An enzyme-linked immunoassay (EIA) for 3 alpha-hydroxy-5 beta-androstane-11,17-dione (11-O-ETIO) has been used to show a substantial rise in the rate of release of immunoreactive compounds into the water when males are injected with salmon gonadotropin releasing hormone analogue. Similar increases were noted for 11-ketotestosterone and 17,20 beta-dihydroxypregn-4-en-3-one. Partitioning of the extracts between diethyl ether and water showed the presence of both free and conjugated immunoreactive 11-O-ETIO. Only conjugated immunoreactivity was found in urine (implying that free steroid is released via the gills). The identity of the conjugates was probed by using HPLC, EIA, and mass spectrometry and removal of sulfate and glucosiduronate groups. Immunoreactivity in the conjugated fraction was found to be due mainly to 3 alpha,17beta-dihydroxy-5 beta-androstan-11-one 17-sulfate. However, the evidence was also strong for the presence in water extracts of substantial amounts of 3 alpha-hydroxy-5 beta-androstane-11,17-dione 3-glucosiduronate (which could be detected only by EIA after removal of the glucosiduronate group with beta-glucuronidase). There were also small amounts of 3 alpha-hydroxy-5 beta-androstane-11,17-dione 3-sulfate and 3 alpha,17beta-dihydroxy-5 beta-androstan-11-one 17-glucosiduronate. These studies give some idea of the types, amounts, and ratios of 11-O-ETIO derivatives that are released by reproductive N. melanostomus and will aid further research into the putative pheromonal roles of 5 beta,3 alpha-reduced androgens in this species.


Asunto(s)
Etiocolanolona/análogos & derivados , Perciformes/fisiología , Feromonas/metabolismo , Reproducción/fisiología , Animales , Fraccionamiento Químico/métodos , Cromatografía Líquida de Alta Presión , Etiocolanolona/análisis , Etiocolanolona/química , Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/análogos & derivados , Hidroxiprogesteronas/análisis , Técnicas para Inmunoenzimas , Inyecciones , Masculino , Espectrometría de Masas , Salmón , Saponinas/análisis , Testosterona/análogos & derivados , Testosterona/análisis , Testosterona/orina , Agua/química
3.
J Chem Ecol ; 37(3): 260-2, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21365215

RESUMEN

The round goby, Neogobius melanostomus, is a highly successful invasive species in the Laurentian Great Lakes. Previous behavioral studies implied that females are attracted by pheromones to the nests of reproductive males, and that males release putative steroidal pheromones--unconjugated as well as conjugated forms of 3α-hydroxy-5ß-androstane-11,17-dione (11-O-ETIO)-following stimulation of the hypothalamic--gonadal axis with salmon gonadotropin releasing hormone analog (sGnRHa). In this study, we tested the olfactory system of females in response to extracts containing these released steroids. We compared electrical field potential responses from the olfactory epithelium (electro-olfactogram, EOG) of non-reproductive females to methanol extracts of water that previously held males, collected before and after injection of the males with sGnRHa or saline. The females showed increased EOG responses to the post-injection extracts when males were treated with sGnRHa but not saline. This finding provides further evidence for interactions between male and female N. melanostomus via steroidal reproductive pheromones.


Asunto(s)
Etiocolanolona/análogos & derivados , Perciformes/fisiología , Reproducción/fisiología , Olfato , Animales , Electrofisiología/métodos , Etiocolanolona/análisis , Etiocolanolona/metabolismo , Femenino , Hormona Liberadora de Gonadotropina/administración & dosificación , Hormona Liberadora de Gonadotropina/análogos & derivados , Masculino , Vías Olfatorias/fisiología , Conducta Sexual Animal
4.
Drug Test Anal ; 13(11-12): 1835-1851, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34648228

RESUMEN

The testing strategy for the detection of testosterone (T) or T-prohormones is based on the longitudinal evaluation of urinary steroid concentrations accompanied by subsequent isotope ratio mass spectrometry (IRMS)-based confirmation of samples showing atypical concentrations or concentration ratios. In recent years, the IRMS methodology focussed more and more on T itself and on the metabolites of T, 5α- and 5ß-androstanediol. These target analytes showed the best sensitivity and retrospectivity, but their use has occasionally been challenging due to their comparably low urinary concentrations. Conversely, the carbon isotope ratios (CIR) of the main urinary metabolites of T, androsterone (A) and etiocholanolone (EITO), can readily be measured even from low urine volumes; those however, commonly offer a lower sensitivity and shorter retrospectivity in uncovering T misuse. Within this study, the CIRs of A and ETIO were combined with their urinary concentrations, resulting in a single parameter referred to as 'difference from weighted mean' (DWM). Both glucuronidated and sulfated steroids were investigated, encompassing a reference population (n = 110), longitudinal studies on three individuals, influence of ethanol in two individuals, and re-analysis of several administration studies including T, dihydrotestosterone, androstenedione, epiandrosterone, dehydroepiandrosterone, and T-gel. Especially DWM calculated for the sulfoconjugated steroids significantly prolonged the detection time of steroid hormone administrations when individual reference ranges were applied. Administration studies employing T encompassing CIR common for Europe (-23.8‰ and -24.4‰) were investigated and, even though for a significantly shorter time period and less pronounced, DWM could demonstrate the exogenous source of T metabolites.


Asunto(s)
Androsterona/análisis , Etiocolanolona/análisis , Congéneres de la Testosterona/análisis , Testosterona/análisis , Androsterona/orina , Isótopos de Carbono , Doping en los Deportes/prevención & control , Etanol/administración & dosificación , Etanol/farmacología , Etiocolanolona/orina , Femenino , Humanos , Estudios Longitudinales , Masculino , Espectrometría de Masas/métodos , Persona de Mediana Edad , Detección de Abuso de Sustancias/métodos , Testosterona/orina , Congéneres de la Testosterona/orina
5.
Anal Chem ; 82(14): 6000-7, 2010 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-20560527

RESUMEN

Androgen deprivation therapy is the most common treatment option for advanced prostate cancer. Almost all prostate cancers recur during androgen deprivation therapy, and new evidence suggests that androgen receptor activation persists despite castrate levels of circulating androgens. Quantitation of tissue levels of androgens is critical to understanding the mechanism of recurrence of prostate cancer during androgen deprivation therapy. A liquid chromatography atmospheric pressure photoionization tandem mass spectrometric method was developed for quantitation of tissue levels of androgens. Quantitation of the saturated keto-steroids dihydrotestosterone and 5-alpha-androstanedione required detection of a novel parent ion, [M + 15](+). The nature of this parent ion was explored, and the method was applied to prostate tissue and cell culture with comparison to results achieved using electrospray ionization.


Asunto(s)
Andrógenos/análisis , Neoplasias de la Próstata/terapia , Espectrometría de Masas en Tándem/métodos , Presión Atmosférica , Cromatografía Líquida de Alta Presión/métodos , Dihidrotestosterona/análisis , Etiocolanolona/análogos & derivados , Etiocolanolona/análisis , Humanos , Masculino
6.
J Pharmacol Toxicol Methods ; 106: 106938, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33080389

RESUMEN

BACKGROUND: Urinary sulfate fraction of the anabolic androgenic steroids is not analyzed routinely in anti-doping analyses but has demonstrated in the last years an increasing interest among the anti-doping community. Sulfate conjugates are linked to plasma proteins increasing the residence time in the body compared to glucuro-conjugated metabolites, and then their analyses may allow improving the detection time window of specific metabolites. Hydrolysis of sulfates can be made enzymatically or chemically and can be challenging, depending on the strategy selected. METHODS: Hydrolysis by solvolysis was validated for metabolic studies, focusing on setting a quality control able to assess the hydrolytic step. To the internal standards mixture, androsterone-D4 and etiocholanolone-D5 sulfate were added. The proposed protocol was applied over samples collected after dehydroepiandrosterone (DHEA) administrations. RESULTS: The stability of the structures showed good results, and no evident formation of degradation products was observed. Internal standard to monitor the efficiency of hydrolysis, recovery, and retention time was successfully introduced. Additional analytes (4ß-hydroxy-DHEA, 5-androstene-3ß,17ß-diol and 5α-androstane-3ß,17ß-diol) were found to be affected besides of DHEA and epiandrosterone (epiA) as previously described. CONCLUSIONS: Results in terms of linearity, precision, and accuracy, showed that the method is suitable to quantify seven analytes in urine in the sulfated fraction. The validated method was successfully applied to urine samples after administration of DHEA to detect this compound in the sulfate fraction and preliminarily to negative samples from athletes of both sexes, to determine Q1 and Q3 inter-quartiles. A quality control assessment for the hydrolysis efficiency was established for every individual sample.


Asunto(s)
Sulfato de Deshidroepiandrosterona/análisis , Doping en los Deportes/prevención & control , Detección de Abuso de Sustancias/métodos , Administración Oral , Adulto , Androsterona/análogos & derivados , Androsterona/análisis , Androsterona/química , Androsterona/orina , Sulfato de Deshidroepiandrosterona/administración & dosificación , Sulfato de Deshidroepiandrosterona/química , Sulfato de Deshidroepiandrosterona/orina , Etiocolanolona/análisis , Etiocolanolona/química , Etiocolanolona/orina , Femenino , Cromatografía de Gases y Espectrometría de Masas , Voluntarios Sanos , Humanos , Hidrólisis , Masculino , Persona de Mediana Edad , Estándares de Referencia
7.
J Chromatogr A ; 1196-1197: 153-60, 2008 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-18501914

RESUMEN

Together with steroid glucuronides, sulfoconjugates may be used as markers of steroid administration as well as endogenous steroid production. A fast and sensitive analytical procedure has been developed for the simultaneous separation, determination and quantification of sulfate and glucuronide derivatives of testosterone (T), epitestosterone (E), androsterone (A), etiocholanolone (Etio) and dehydroepiandrosterone (DHEA) in human urine. First, a weak anion-exchange solid-phase extraction support (SPE Oasis WAX) was used for complete and rapid separation of sulfates and glucuronides in two extracts after loading of urine sample (2 mL). Then sulfates were analyzed directly by high-performance liquid chromatography-ion-trap mass spectrometry (LC-MS/MS) with electrospray ionization in negative mode. Chromatographic separation of the targeted sulfoconjugates was achieved using a Waters XBridge C18 column (150 mm x 4.6 mm I.D., 5 microm) with gradient elution. Assay validation demonstrated good performance for instance for T sulfate (TS) and E sulfate (ES) in terms of trueness (89-107%), repeatability (3.4-22%) and intermediate precision (5.8-22%) over the range of 2-200 ng/mL (corresponding to 1.5-147 ng/mL as free steroids). Results obtained on biological samples demonstrated the suitability of this analytical strategy for direct measurement of androgen sulfoconjugates and glucuroconjugates in human urine.


Asunto(s)
Andrógenos/orina , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas/métodos , Andrógenos/análisis , Andrógenos/aislamiento & purificación , Androsterona/análisis , Androsterona/aislamiento & purificación , Androsterona/orina , Deshidroepiandrosterona/análisis , Deshidroepiandrosterona/aislamiento & purificación , Deshidroepiandrosterona/orina , Epitestosterona/análisis , Epitestosterona/aislamiento & purificación , Epitestosterona/orina , Etiocolanolona/análisis , Etiocolanolona/aislamiento & purificación , Etiocolanolona/orina , Humanos , Reproducibilidad de los Resultados , Extracción en Fase Sólida , Testosterona/análisis , Testosterona/aislamiento & purificación , Testosterona/orina
8.
J Steroid Biochem Mol Biol ; 165(Pt B): 212-218, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27328448

RESUMEN

Testosterone (T) has traditionally been the most commonly reported doping agent by doping control laboratories. The screening of T misuse is performed by the quantification of six endogenous androgenic steroids and the ratio T/E included in the Athlete Biological Passport (ABP). The inclusion of additional metabolites can improve the screening capabilities of ABP. In this study, the potential of 3α-glucuronide-6ß-hydroxyandrosterone (6OH-Andros3G) and 3α-glucuronide-6ß-hydroxyetiocholanolone (6OH-Etio3G) as markers of T oral administration was evaluated. These glucuronides have been shown to be resistant to enzymatic hydrolysis and their quantification by means of liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was reported as the only way to obtain feasible results. Urine samples were collected from five volunteers before and after the oral administration of 40mg of T undecanoate and were analyzed by a LC-MS/MS method recently developed. Concentration of 6OH-Andros3G and 6OH-Etio3G compounds and those of the glucuronides of T (TG), epitestosterone (EG), androsterone and etiocholanolone were established and different concentration ratios were calculated. The detection windows (DWs) for the T administration obtained by each selected ratio were compared to the one of TG/EG. The results showed that four out of the nine tested markers presented DWs much larger for all volunteers than those obtained by the World Anti-Doping Agency established T/E marker or other alternative markers. The 6OH-Andros3G/EG, 6OH-Etio3G/EG, 6OH-Andros3G/TG and 6OH-Etio3G/TG markers were able to identify the T abuse up to 96h after the administration, extending our detection capability for the misuse up to 84h more than the classic marker. The importance of these markers was also highlighted by their prolonged capacity to detect the T misuse in the case of one volunteer whose TG/EG barely exceeded his individual threshold. As a consequence, the four markers presented in this study seem to have an exceptional potential as biomarkers of T oral administration.


Asunto(s)
Glucurónidos/análisis , Detección de Abuso de Sustancias/métodos , Testosterona/análogos & derivados , Administración Oral , Androsterona/análisis , Biomarcadores/análisis , Cromatografía Líquida de Alta Presión , Doping en los Deportes/prevención & control , Epitestosterona/análisis , Etiocolanolona/análisis , Cromatografía de Gases y Espectrometría de Masas , Voluntarios Sanos , Humanos , Hidrólisis , Masculino , Reproducibilidad de los Resultados , Esteroides/análisis , Espectrometría de Masas en Tándem , Testosterona/administración & dosificación , Testosterona/análisis
9.
PLoS One ; 11(4): e0153161, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27077741

RESUMEN

In mammals, glucocorticoid (i.e. GC) levels have been associated with specific life-history stages and transitions, reproductive strategies, and a plethora of behaviors. Assessment of adrenocortical activity via measurement of glucocorticoid metabolites in feces (FGCM) has greatly facilitated data collection from wild animals, due to its non-invasive nature, and thus has become an established tool in behavioral ecology and conservation biology. The aim of our study was to validate a fecal glucocorticoid assay for assessing adrenocortical activity in meerkats (Suricata suricatta), by comparing the suitability of three GC enzyme immunoassays (corticosterone, 11ß-hydroxyetiocholanolone and 11oxo-etiocholanolone) in detecting FGCM increases in adult males and females following a pharmacological challenge with adrenocorticotropic hormone (ACTH) and biological stimuli. In addition, we investigated the time course characterizing FGCM excretion, the effect of age, sex and time of day on FGCM levels and assessed the potential effects of soil contamination (sand) on FGCM patterns. Our results show that the group specific 11ß-hydroxyetiocholanolone assay was most sensitive to FGCM alterations, detecting significant and most distinctive elevations in FGCM levels around 25 h after ACTH administration. We found no age and sex differences in basal FGCM or on peak response levels to ACTH, but a marked diurnal pattern, with FGCM levels being substantially higher in the morning than later during the day. Soil contamination did not significantly affect FGCM patterns. Our results emphasize the importance of conducting assay validations to characterize species-specific endocrine excretion patterns, a crucial step to all animal endocrinology studies using a non-invasive approach.


Asunto(s)
Heces/química , Glucocorticoides/análisis , Herpestidae/fisiología , Sistema Hipotálamo-Hipofisario/fisiología , Sistema Hipófiso-Suprarrenal/fisiología , Hormona Adrenocorticotrópica/farmacología , Androsterona/análogos & derivados , Androsterona/análisis , Animales , Fenómenos Biológicos , Cromatografía Líquida de Alta Presión , Corticosterona/análisis , Etiocolanolona/análisis , Femenino , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Inmunoensayo , Masculino , Fenómenos Fisiológicos , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Reproducibilidad de los Resultados , Suelo/química , Factores de Tiempo
10.
Drug Test Anal ; 8(11-12): 1197-1203, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27714988

RESUMEN

The laboratory profile of intranasal testosterone gel has not been previously reported from an anti-doping perspective. Because intranasal testosterone gel is newly available as a commercial product, we sought to examine the laboratory parameters following administration of this formulation, with particular attention to anti-doping guidelines. Five healthy and active male subjects were administered testosterone intranasal gel three times daily for four weeks, using a pattern of five consecutive days on, two days off. Urine was collected after each five-day round of drug administration and analyzed using a full steroid screen and isotope ratio mass spectrometry (IRMS). Windows of detection for elevated testosterone/epitestosterone (T/E) and other steroid ratios, World Anti-Doping Agency (WADA) athlete biological passport (ABP) findings, and IRMS results were analyzed in this study. In the 0-24 h window post-administration, 70% of samples were flagged with a suspicious steroid profile and 85% were flagged as atypical passport findings according to the WADA ABP steroid module. In the 24-48 h window, 0% of samples displayed suspicious steroid profiles while 40% resulted in atypical passport findings. IRMS testing confirmed the presence of exogenous testosterone in 90% and 40% of samples in the 0-24 h and 24-48 h windows post-administration, respectively. Additionally, IRMS data were analyzed to determine commonalities in the population changes in δ13 C values of testosterone, androsterone, etiocholanolone, 5αAdiol, and 5ßAdiol. Though no discernible metabolic trend of the route of administration was identified, we discovered that intranasal gel testosterone is detectable using conventional anti-doping tests. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Administración Intranasal/métodos , Androsterona/análisis , Biomarcadores/análisis , Isótopos de Carbono/química , Epitestosterona/análisis , Etiocolanolona/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Esteroides/análisis , Detección de Abuso de Sustancias/métodos , Testosterona/administración & dosificación , Androsterona/química , Atletas , Biomarcadores/metabolismo , Doping en los Deportes , Epitestosterona/química , Etiocolanolona/química , Humanos , Espectrometría de Masas , Esteroides/química , Testosterona/química , Factores de Tiempo
11.
Drug Test Anal ; 8(11-12): 1204-1211, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27739243

RESUMEN

Measuring carbon isotope ratios (CIRs) of urinary analytes represents a cornerstone of doping control analysis and has been particularly optimized for the detection of the misuse of endogenous steroids. Isotope ratio mass spectrometry (IRMS) of appropriate quality, however, necessitates adequate purities of the investigated steroids, which requires extensive pre-analytical sample clean-up steps due to both the natural presence of the target analytes and the high complexity of the matrix. In order to accelerate the sample preparation and increase the automation of the process, the use of multidimensional gas chromatography (MDGC) prior to IRMS experiments, was investigated. A well-established instrumental configuration based on two independent GC ovens and one heart-cutting device was optimized. The first dimension (1D) separation was obtained by a non-polar column which assured high efficiency and good loading capacity, while the second dimension (2D), based on a mid-polar stationary phase, provided good selectivity. A flame ionization detector monitored the 1D, and the 2D was simultaneously recorded by isotope ratio and quadrupole mass spectrometry. The assembled MDGC set-up was applied for measuring testosterone, 5α- and 5ß-androstanediol, androsterone, and etiocholanolone as target compounds and pregnanediol as endogenous reference compound. The urine sample were pretreated by conventional sample preparation steps comprising solid-phase extraction, hydrolysis, and liquid-liquid extraction. The extract obtained was acetylated and different aliquots were injected into the MDGC system. Two high performance liquid chromatography steps, conventionally adopted prior to CIR measurements, were replaced by the MDGC approach. The obtained values were consistent with the conventional ones. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Anabolizantes/orina , Androsterona/orina , Isótopos de Carbono/orina , Cromatografía Líquida de Alta Presión/métodos , Etiocolanolona/orina , Cromatografía de Gases y Espectrometría de Masas/métodos , Esteroides/análisis , Testosterona/orina , Anabolizantes/química , Androsterona/análisis , Androsterona/química , Cromatografía de Gases , Doping en los Deportes , Etiocolanolona/análisis , Etiocolanolona/química , Humanos , Espectrometría de Masas , Esteroides/química , Esteroides/metabolismo , Testosterona/análisis
12.
J Steroid Biochem Mol Biol ; 54(5-6): 245-50, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7577706

RESUMEN

This study reports that, in contrast to previous findings, basic fibroblast growth factor (FGF-2) stimulates immature Leydig cell steroidogenesis in the absence of luteinizing hormone (LH). Heparan sulphate proteoglycans (HSPGs) are essential for this action of FGF-2 and the data suggest that HSPG/FGF-2 interactions have a significant role in the maintenance of immature Leydig cell steroidogenesis. Culture conditions were established for the maintenance of immature rat Leydig cells steroidogenesis in vitro for at least 2 days. Under these conditions the effect of exposure to FGF-2 at doses ranging from 0.1-10 ng/ml was shown to cause a significant stimulation of basal, but not LH-stimulated, 5 alpha-androstane 3 alpha,17 beta-diol production over 24h in culture. This stimulatory action on basal steroidogenesis is mediated through HSPG, as it was blocked by the addition of heparin (100 micrograms/ml), sodium chlorate (25mM) and protamine sulphate (5 micrograms/ml). These data demonstrate the involvement of HSPG in regulating FGF-2 action on Leydig cells and a potential role for Leydig cell HSPG in mediating paracrine regulatory actions of other heparin binding growth factors.


Asunto(s)
Etiocolanolona/análogos & derivados , Factor 2 de Crecimiento de Fibroblastos/farmacología , Células Intersticiales del Testículo/metabolismo , Proteoglicanos/metabolismo , Animales , Células Cultivadas , Relación Dosis-Respuesta a Droga , Etiocolanolona/análisis , Masculino , Ratas , Ratas Sprague-Dawley
13.
J Chromatogr Sci ; 38(11): 477-82, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11105770

RESUMEN

The solubility of testosterone, boldenone, androstenone, etiocholanolone, and epitestosterone are measured in pure supercritical CO2. Testosterone exhibited the highest solubility in supercritical CO2. The solubility of all steroids except epitestosterone increased by one order of magnitude with increasing pressure from 100 to 400 atm. Epitestosterone had the lowest solubility in supercritical CO2 and its solubility was not affected by pressure. The extraction efficiency of steroids from an aqueous saline environment exceeded 95%. Because of the partial solubility of water in supercritical CO2, the addition of a moisture trap after the aqueous vessel is necessary to prevent the plugging and deterioration of the gas chromatographic (GC) column. It is demonstrated that on-line supercritical fluid extraction-GC-mass spectrometry is feasible for the quantitative extraction and analysis of steroids from both saline and urine solutions. However, it is determined that the adsorbent vessel filled with Hydromatrix is not sufficient to trap all the moisture, and after 3 to 4 extractions, the GC column efficiency lowered.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Esteroides/análisis , Testosterona/análogos & derivados , Testosterona/análisis , Dióxido de Carbono , Epitestosterona/análisis , Etiocolanolona/análisis , Control de Calidad , Solubilidad
14.
Psychoneuroendocrinology ; 48: 19-28, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24980035

RESUMEN

The social environment can have a powerful impact on an individual's stress response and thus affect health and biological fitness. Positive social interactions are particularly important for females of species living in complex societies, e.g. humans and non-human primates. Existing studies have mainly focussed on the effect of same-sex social interaction on the stress response, rather than both same- and opposite-sex social interaction simultaneously. However, consideration of both may be crucial since females may have different 'social needs' across different life-history stages. Applying the conceptual framework of allostasis, we tested the hypothesis that female allostatic load (measured through faecal glucocorticoid levels [fGCs]), of wild seasonally breeding Assamese macaques (Macaca assamensis), would increase if their social needs were not maintained in accordance with season. We found significant seasonal differences in same- and opposite-sex sociality which, depending on season, predicted female fGCs. In the mating season, females which spent more time close to males and more frequently groomed with them exhibited lower fGCs. In the non-mating season, when female-male interaction was infrequent, positive female-female sociality predicted lower fGCs. Our results support the hypothesis that same- and opposite-sex sociopositive interactions, specific to certain life-history stages, can mediate fGCs. We interpret this as a consequence of the positive direct and/or indirect effects of social contact in accordance with interactions pertaining to a given life-history stage, which are likely to impact positively upon fitness.


Asunto(s)
Hidrocortisona/metabolismo , Macaca , Conducta Sexual Animal/fisiología , Conducta Social , Medio Social , Estrés Fisiológico , Animales , Animales Salvajes , Etiocolanolona/análisis , Etiocolanolona/metabolismo , Heces/química , Femenino , Aseo Animal , Hidrocortisona/análisis , Macaca/metabolismo , Macaca/psicología , Masculino , Estaciones del Año , Predominio Social
15.
Vet Res Commun ; 34(2): 185-95, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20182914

RESUMEN

Glucocorticoids or their metabolites can be measured in several body fluids or excreta, including plasma, saliva, urine and faeces. In recent years the measurement of glucocorticoid metabolites (GCMs) in faeces has gained increasing attention, because of its suitability for wild populations. In horses, however, the group-specific enzyme immunoassay described so far has a limited practicability due to its complex extraction procedure. Therefore, we tested the applicability of other enzyme immunoassays for glucocorticoid metabolites. The present study clearly proved that an enzyme immunoassay (EIA) for 11-oxoaetiocholanolone using 11-oxoaetiocholanolone-17-CMO: BSA (3alpha,11-oxo-A EIA) as antigen showed high amounts of immunoreactive substances. Therefore it was possible to use just a small amount of the supernatant of a methanolic suspension of faeces. The results correlated well with the already described method for measuring GCMs in horse faeces, i.e. analysing the samples with an EIA after a two step clean up procedure of the samples (Merl et al. 2000). In addition, the 3alpha,11-oxo-A EIA has the advantage of providing a bigger difference between baseline values and peak values after ACTH stimulation. The new assay increased the accuracy of the test, lowered the expenses per sample, and storing samples at room temperature after collection was less critical than with other assays investigated in our study. This is a big advantage both in the field of wildlife management of equids and in the field of equestrian sports and it shows the importance of choosing an assay which is in good accordance with the metabolites excreted in a given species.


Asunto(s)
Heces/química , Glucocorticoides/metabolismo , Caballos/metabolismo , Técnicas para Inmunoenzimas/veterinaria , Estrés Fisiológico/fisiología , Hormona Adrenocorticotrópica/farmacología , Animales , Dexametasona/metabolismo , Etiocolanolona/análogos & derivados , Etiocolanolona/análisis , Etiocolanolona/metabolismo , Femenino , Glucocorticoides/análisis , Técnicas para Inmunoenzimas/métodos , Masculino
16.
Endocrinol Metab Clin North Am ; 39(1): 59-73, viii-ix, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20122450

RESUMEN

The Athlete Biological Passport (ABP) is an individual electronic document that collects data regarding a specific athlete that is useful in differentiating between natural physiologic variations of selected biomarkers and deviations caused by artificial manipulations. A subsidiary of the endocrine module of the ABP, that which here is called Athlete Steroidal Passport (ASP), collects data on markers of an altered metabolism of endogenous steroidal hormones measured in urine samples. The ASP aims to identify not only doping with anabolic-androgenic steroids, but also most indirect steroid doping strategies such as doping with estrogen receptor antagonists and aromatase inhibitors. Development of specific markers of steroid doping, use of the athlete's previous measurements to define individual limits, with the athlete becoming his or her own reference, the inclusion of heterogeneous factors such as the UDPglucuronosyltransferase B17 genotype of the athlete, the knowledge of potentially confounding effects such as heavy alcohol consumption, the development of an external quality control system to control analytical uncertainty, and finally the use of Bayesian inferential methods to evaluate the value of indirect evidence have made the ASP a valuable alternative to deter steroid doping in elite sports. The ASP can be used to target athletes for gas chromatography/combustion/ isotope ratio mass spectrometry (GC/C/IRMS) testing, to withdraw temporarily the athlete from competing when an abnormality has been detected, and ultimately to lead to an antidoping infraction if that abnormality cannot be explained by a medical condition. Although the ASP has been developed primarily to ensure fairness in elite sports, its application in endocrinology for clinical purposes is straightforward in an evidence-based medicine paradigm.


Asunto(s)
Anabolizantes/análisis , Andrógenos/análisis , Atletas , Doping en los Deportes/prevención & control , Factores de Edad , Anabolizantes/administración & dosificación , Andrógenos/administración & dosificación , Androstano-3,17-diol/análisis , Teorema de Bayes , Biomarcadores/análisis , Deshidroepiandrosterona/análisis , Epitestosterona/análisis , Etiocolanolona/análisis , Femenino , Variación Genética , Humanos , Masculino , Resistencia Física/efectos de los fármacos , Resistencia Física/fisiología , Valores de Referencia , Factores Sexuales , Testosterona/análisis , Testosterona/fisiología
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