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1.
Drug Test Anal ; 13(11-12): 1835-1851, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34648228

RESUMO

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.


Assuntos
Androsterona/análise , Etiocolanolona/análise , Congêneres da Testosterona/análise , Testosterona/análise , Androsterona/urina , Isótopos de Carbono , Doping nos Esportes/prevenção & controle , Etanol/administração & dosagem , Etanol/farmacologia , Etiocolanolona/urina , Feminino , Humanos , Estudos Longitudinais , Masculino , Espectrometria de Massas/métodos , Pessoa de Meia-Idade , Detecção do Abuso de Substâncias/métodos , Testosterona/urina , Congêneres da Testosterona/urina
2.
Drug Test Anal ; 13(11-12): 1822-1834, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33942526

RESUMO

Intact phase II steroid metabolites have poor product ion mass spectra under collision-induced dissociation (CID) conditions. Therefore, we present herein the liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/(MS)) behavior of intact phase II metabolites of oxosteroids after derivatization. Based on the fact that Girard's reagent T (GRT), as derivatization reagent, was both convenient and efficient in terms of the enhancement in the ionization efficiency and the production of diagnostic product ions related to the steroid moiety, the latter was preferably selected between methoxamine and hydroxylamine upon the model compounds of androsterone glucuronide and androsterone sulfate. Sixteen different glucuronides and 29 sulfate conjugated metabolites of anabolic androgenic steroids (AASs), available either as pure reference materials or synthesized/extracted from administration studies, were derivatized with GRT, and their product ion spectra are presented. Product ion spectra include in all cases high number of product ions that in some cases are characteristic for certain structures of the steroid backbone. More specifically, preliminary results have shown major differences in fragmentation pattern for 17α/17ß-isomers of the sulfate conjugates, but limited differentiation for 17α/17ß-isomers of glucuronide conjugates and for 3α/3ß- and 5α/5ß-stereoisomers of both sulfate and glucuronide conjugates. Further to the suggestion of the current work, application on mesterolone administration studies confirmed-according to the World Anti-Doping Agency (WADA) TD2015IDCR-the presence of seven intact phase II metabolites, one glucuronide and six sulfates with use of LC-ESI-MS/(MS).


Assuntos
Anabolizantes/análise , Androsterona/análogos & derivados , Doping nos Esportes/prevenção & controle , Mesterolona/análise , Anabolizantes/química , Androsterona/análise , Androsterona/química , Betaína/análogos & derivados , Betaína/química , Cromatografia Líquida/métodos , Humanos , Mesterolona/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
3.
Int J Mol Sci ; 22(2)2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33418978

RESUMO

The peripheral zone (PZ) and transition zone (TZ) represent about 70% of the human prostate gland with each zone having differential ability to develop prostate cancer. Androgens and their receptor are the primary driving cause of prostate cancer growth and eventually castration-resistant prostate cancer (CRPC). De novo steroidogenesis has been identified as a key mechanism that develops during CRPC. Currently, there is very limited information available on human prostate tissue steroidogenesis. The purpose of the present study was to investigate steroid metabolism in human prostate cancer tissues with comparison between PZ and TZ. Human prostate cancer tumors were procured from the patients who underwent radical prostatectomy without any neoadjuvant therapy. Human prostate homogenates were used to quantify steroid levels intrinsically present in the tissues as well as formed after incubation with 2 µg/mL of 17-hydroxypregnenolone (17-OH-pregnenolone) or progesterone. A Waters Acquity ultraperformance liquid chromatography coupled to a Quattro Premier XE tandem quadrupole mass spectrometer using a C18 column was used to measure thirteen steroids from the classical and backdoor steroidogenesis pathways. The intrinsic prostate tissue steroid levels were similar between PZ and TZ with dehydroepiandrosterone (DHEA), dihydrotestosterone (DHT), pregnenolone and 17-OH-pregnenolone levels higher than the other steroids measured. Interestingly, 5-pregnan-3,20-dione, 5-pregnan-3-ol-20-one, and 5-pregnan-17-ol-3,20-dione formation was significantly higher in both the zones of prostate tissues, whereas, androstenedione, testosterone, DHT, and progesterone levels were significantly lower after 60 min incubation compared to the 0 min control incubations. The incubations with progesterone had a similar outcome with 5-pregnan-3,20-dione and 5-pregnan-3-ol-20-one levels were elevated and the levels of DHT were lower in both PZ and TZ tissues. The net changes in steroid formation after the incubation were more observable with 17-OH-pregnenolone than with progesterone. In our knowledge, this is the first report of comprehensive analyses of intrinsic prostate tissue steroids and precursor-driven steroid metabolism using a sensitive liquid chromatography-mass spectrometry assay. In summary, the PZ and TZ of human prostate exhibited similar steroidogenic ability with distinction in the manner each zone utilizes the steroid precursors to divert the activity towards backdoor pathway through a complex matrix of steroidogenic mechanisms.


Assuntos
Neoplasias da Próstata/patologia , Esteroides/metabolismo , Androstenodiona/análise , Androsterona/análise , Cromatografia Líquida de Alta Pressão , Humanos , Masculino , Espectrometria de Massas , Progesterona/análogos & derivados , Progesterona/análise , Progesterona/metabolismo , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Esteroides/análise , Esteroides/química , Testosterona/análise
4.
Drug Test Anal ; 13(4): 770-784, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33242373

RESUMO

The detection of 19-norsteroids abuse in doping controls currently relies on the determination of 19-norandrosterone (19-NA) by gas chromatography-tandem mass spectrometry (GC-MS/MS). An additional confirmatory analysis by gas chromatography coupled to isotope ratio mass spectrometry (GC-C-IRMS) is performed on samples showing 19-NA concentrations between 2.5 and 15 ng/ml and not originated from pregnant female athletes or female treated with 19-norethisterone. 19-Noretiocholanolone (19-NE) is typically produced to a lesser extent as a secondary metabolite. The aim of this work was to improve the GC-C-IRMS confirmation procedure for the detection of 19-norsteroids misuse. Both 19-NA and 19-NE were analyzed as target compounds (TCs), whereas androsterone (A), pregnanediol (PD), and pregnanetriol (PT) were selected as endogenous reference compounds (ERCs). The method was validated and applied to urine samples collected by three male volunteers after the administration of nandrolone-based formulations. Before the instrumental analysis, urine samples (<25 ml) were hydrolyzed with ß-glucuronidase from Escherichia coli and extracted with n-pentane. Compounds of interest were purified through a single (for PT) or double (for 19-NE, 19-NA, A, and PD) liquid chromatographic step, to reduce the background noise and eliminate interferences that could have affect the accuracy of δ13 C values. The limit of quantification (LOQ) of 2 ng/ml was ensured for both 19-NA and 19-NE. The 19-NE determination could be helpful in case of "unstable" urine samples, in late excretion phases or when coadministration with 5α-reductase inhibitors occur.


Assuntos
Doping nos Esportes/prevenção & controle , Estranos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , Adulto , Androsterona/análise , Feminino , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Nandrolona/administração & dosagem , Nandrolona/metabolismo , Pregnanodiol/análise , Pregnanotriol/análise
5.
J Pharmacol Toxicol Methods ; 106: 106938, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33080389

RESUMO

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.


Assuntos
Sulfato de Desidroepiandrosterona/análise , Doping nos Esportes/prevenção & controle , Detecção do Abuso de Substâncias/métodos , Administração Oral , Adulto , Androsterona/análogos & derivados , Androsterona/análise , Androsterona/química , Androsterona/urina , Sulfato de Desidroepiandrosterona/administração & dosagem , Sulfato de Desidroepiandrosterona/química , Sulfato de Desidroepiandrosterona/urina , Etiocolanolona/análise , Etiocolanolona/química , Etiocolanolona/urina , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Voluntários Saudáveis , Humanos , Hidrólise , Masculino , Pessoa de Meia-Idade , Padrões de Referência
6.
Drug Test Anal ; 12(11-12): 1554-1560, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32697436

RESUMO

Identification and evaluation of long-term markers is crucial in prolonging the detection window for anabolic steroid abuse in sport. Recently, sulfoconjugated epiandrosterone was identified as a potential long-term marker for the abuse of certain endogenous anabolic agents, including testosterone, which continues to be widely used as a performance enhancing agent in sport. To evaluate the applicability of epiandrosterone sulfate as a marker for testosterone use, administration studies were conducted with multiple modes of testosterone administration - transdermal, intramuscular, and subcutaneous. A modified sample preparation method was used to collect both glucuronidated and sulfoconjugated analytes of interest. Carbon isotope ratio measurements from the administration studies are presented here. Epiandrosterone was less effective than the conventionally used target compounds for detection of the low dose application (transdermal gel). With intramuscular administration, epiandrosterone was more diagnostic than with transdermal administration, but it did not prolong the detection window more than the conventional target compounds. With subcutaneous administration, the doses administered to the subjects were varied and the effect on the epiandrosterone values was dependent on the magnitude of the dose administered. Epiandrosterone does not appear to be a useful marker in the detection of low dose testosterone administration. It is responsive to higher dose administration, but it does not provide an extension of the detection window relative to conventional target compounds.


Assuntos
Anabolizantes/administração & dosagem , Anabolizantes/metabolismo , Androsterona/metabolismo , Detecção do Abuso de Substâncias/normas , Testosterona/administração & dosagem , Testosterona/metabolismo , Administração Cutânea , Adulto , Anabolizantes/análise , Androsterona/análise , Biomarcadores/metabolismo , Doping nos Esportes/métodos , Doping nos Esportes/prevenção & controle , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa-Espectrometria de Massas/normas , Géis , Humanos , Injeções Intramusculares , Injeções Subcutâneas , Absorção Intramuscular/efeitos dos fármacos , Absorção Intramuscular/fisiologia , Masculino , Absorção Cutânea/efeitos dos fármacos , Absorção Cutânea/fisiologia , Absorção Subcutânea/efeitos dos fármacos , Absorção Subcutânea/fisiologia , Detecção do Abuso de Substâncias/métodos , Testosterona/análise
7.
Chemosphere ; 237: 124371, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31369902

RESUMO

Public concerns about potential ecological risks of androgens discharged to the environment through wastewater treatment plants (WWTPs) has resulted in an increased interest regarding the occurrence and fate of androgens in WWTPs. In this study, the occurrence and removal of eight androgens from 12 municipal WWTPs distributed in eleven cities in China were investigated. The composition profiles of eight androgens in influent, effluent, and excess sludge were studied. Multiple factor analyses were performed to reveal the factors affecting the distribution of androgens in WWTP influent. Results showed similar composition profiles of androgens in the studied WWTPs, with androsterone and dehydroepiandrosterone confirmed as the dominant androgens. The distributions of androgens in WWTP influent were related to the chemical oxygen demand in influent and the gross domestic product (GDP) of WWTP-associated cities. The target androgens have high aqueous removal rates, with a mean removal rate of >90%. Additionally, the behaviors of androgens were evaluated by mass balance along anaerobic-anoxic-oxic (AAO) processes in a WWTP, in which many of the androgens were eliminated mainly in the anaerobic tank. Further, 15 biotransformation products of testosterone were identified under anaerobic, anoxic, and aerobic sludge, respectively. Based on these metabolites, a general biotransformation pathway of testosterone under anaerobic, anoxic, and aerobic sludge is presented.


Assuntos
Androgênios/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Androgênios/metabolismo , Androsterona/análise , China , Cidades , Esgotos/química , Testosterona/metabolismo , Instalações de Eliminação de Resíduos , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/metabolismo , Purificação da Água
8.
Meat Sci ; 152: 65-72, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30826630

RESUMO

While forming mixtures is a widely used approach for other raw materials in food industry, it has not yet been systematically analyzed for boar tainted meat. That is why we simultaneously studied four factors relevant for the production of emulsion-type sausages: percentage boar meat (skatole concentrations up to 0.3 µg/g, androstenone up to 3.8 µg/g in melted backfat), duration of traditional smoke and concentration levels of two spices. 16 variants of Frankfurters were produced in two independent studies and evaluated by in total 211 consumers. A linear mixed effects model revealed that increased levels of boar tainted meat significantly reduced consumer acceptance which could not be compensated by increased smoke or spice levels. We propose a non-inferiority test to identify the mixture which is similarly accepted as the reference made without boar tainted meat. Up to 33% tainted boar meat is proposed, assuming a liking drop of 0.5 on a 9 point liking scale as benchmark for an inferior product.


Assuntos
Manipulação de Alimentos/métodos , Produtos da Carne/normas , Paladar , Tecido Adiposo/química , Adolescente , Adulto , Idoso , Androsterona/análise , Animais , Comportamento do Consumidor , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escatol/análise , Suínos
9.
J Steroid Biochem Mol Biol ; 185: 47-56, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30031148

RESUMO

Growth and development of an embryo or fetus during human pregnancy mainly depend on intact hormone biosynthesis and metabolism in maternal amniotic fluid (AF). We investigated the hormonal milieu in AF and developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the determination of 14 sulfated and 6 unconjugated steroids in AF. 65 A F samples (male: female = 35: 30) of mid-gestation ranging from 16th week of gestation to 25th week of gestation were analyzed. Reference data of 20 steroid levels in AF of healthy women were provided. 13 sulfated and 3 unconjugated steroids were for the first time quantified in AF by LC-MS/MS. Highest concentrations were found for pregnenolone sulfate (PregS: mean ±â€¯SD, 8.6 ±â€¯3.7 ng/mL), 17α-hydroxypregnenolone sulfate (17OHPregS: 4.9 ±â€¯2.0 ng/mL), epitestosterone sulfate (eTS: 7.3 ±â€¯3.6 ng/mL), 16α-hydroxydehydroepiandrosterone sulfate (16OH-DHEAS: 21.5 ±â€¯10.7 ng/mL), androsterone sulfate (AnS: 9.2 ±â€¯7.4 ng/mL), estrone sulfate (E1S: 3.0 ±â€¯3.0 ng/mL), estriol 3-sulfate (E3S: 8.1 ±â€¯4.0 ng/mL) and estriol (E3: 1.2 ±â€¯0.4 ng/mL). Only testosterone (T) showed a significant sex difference (p < 0.0001). Correlations between AF steroids mirrored the steroid metabolism of the feto-placental unit, and not only confirmed the classical steroid pathway, but also pointed to a sulfated steroid pathway.


Assuntos
Líquido Amniótico/química , Segundo Trimestre da Gravidez/fisiologia , Esteroides/análise , 17-alfa-Hidroxipregnenolona/análise , Androsterona/análise , Cromatografia Líquida , Desidroepiandrosterona/análise , Epitestosterona/análise , Estriol/análogos & derivados , Estriol/análise , Estrona/análogos & derivados , Estrona/análise , Feminino , Idade Gestacional , Humanos , Masculino , Gravidez , Pregnenolona/análise , Espectrometria de Massas em Tandem
10.
Food Res Int ; 108: 387-395, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29735071

RESUMO

Smoke has often been recommended as a masking agent for boar taint. However, guidelines on how much smoke is necessary have not been established. We compared different smoking parameters in bacon (smoking times) and sausages (smoking times and use of liquid smoke). In streaky bacon from entire male pigs with skatole concentrations of up to 0.6 µg/g and androstenone concentrations of up to 5.8 µg/g in the neck fat, three smoking times were compared: 10, 30 and 60 min. Boar taint was partially, but not fully, masked. The longer the smoking time, the better the masking effect. In sausages from entire male pigs with an average skatole concentration of up to 0.6 µg/g and androstenone concentration of up to 3.6 µg/g (the meat part) or 2.4 µg/g (the fat part) in the neck fat, smoking for 40 and 80 min fully masked the boar taint, whereas only a minor effect was seen after 10 and 20 min smoking. Liquid smoke (0.1%) did not mask boar taint when added to sausages from entire male pigs with an average skatole concentration of 0.36 µg/g (meat) or 0.38 µg/g (fat) and androstenone concentration of 2.3 µg/g (meat) and 2.9 µg/g (fat). To effectively mask boar taint, an intense smoked flavour is therefore necessary, and the longer the smoking time, the better. In contrast, the use of liquid smoke mixed into the product was not effective in the concentrations used in the current study.


Assuntos
Aromatizantes/química , Manipulação de Alimentos/métodos , Produtos da Carne/análise , Carne Vermelha/análise , Olfato , Fumaça , Paladar , Androsterona/análise , Animais , Culinária , Feminino , Temperatura Alta , Humanos , Julgamento , Masculino , Odorantes/análise , Percepção Olfatória , Escatol/análise , Sus scrofa , Percepção Gustatória , Fatores de Tempo
11.
J Sci Food Agric ; 98(6): 2251-2257, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28981163

RESUMO

BACKGROUND: Consumers highly sensitive to androstenone María (AND) will probably reject meat from entire male pigs, which tends to have high levels of this hormone. To avoid this, the effect of different masking strategies (sprinkling with mixed spices or fennel, marinating and breading with garlic-parsley or curry) on the sensory parameters of pork loin chops obtained from entire animals with high levels of AND (1.0-2.9 mg kg-1 AND in fat) and castrated animals (<0.4 mg kg-1 AND in fat), both with low levels of skatole (<0.1 mg kg-1 skatole in fat) was investigated. RESULTS: The garlic-parsley breadcrumbs led to the highest reduction in the perception of AND compared with the other masking strategies used, and preserved the juiciness of the product. There was a negative correlation between AND and fat content. CONCLUSION: AND odor and flavor can be reduced in meat from entire male pigs by using suitable strategies, the best strategy being the garlic-parsley breadcrumbs. © 2017 Society of Chemical Industry.


Assuntos
Androsterona/análise , Culinária/métodos , Carne/análise , Percepção Olfatória , Adulto , Animais , Comportamento do Consumidor , Feminino , Aditivos Alimentares/análise , Alho/química , Humanos , Masculino , Pessoa de Meia-Idade , Odorantes/análise , Petroselinum/química , Escatol/análise , Especiarias/análise , Sus scrofa
12.
Meat Sci ; 136: 104-115, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29121524

RESUMO

This study investigated the effects of ageing period (2 or 7days), endpoint temperature (70 or 75°C), cut type (loin (M. longissimus thoracis et lumborum), silverside (M. biceps femoris), blade (M. triceps brachii) and chuck tender (M. supraspinatus)), cooking method (roast and stir fry (all cuts) and steak (loin only)) on eating quality attributes of pork from entire and immunocastrated male pigs. Higher intramuscular fat levels were found in all cuts from immunocastrated males compared with entire males. Of the seven cut type×cooking method combinations evaluated, shoulder cuts had the lowest fail rate (P<0.001) and loin steak and silverside cuts scored lowest (P<0.001) for tenderness, juiciness, overall liking, quality grade and re-purchase intention. Although no differences in sensory scores due to gender were observed, boar taint was identified in 10% of entire males. Minimising adverse risks in eating quality due to boar taint in males remains a key industry issue to ensure consistent delivery of high quality pork.


Assuntos
Culinária/métodos , Carne Vermelha/análise , Adolescente , Adulto , Idoso , Androsterona/análise , Animais , Distribuição da Gordura Corporal/veterinária , Comportamento do Consumidor , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/química , Orquiectomia/métodos , Orquiectomia/veterinária , Escatol/análise , Sus scrofa , Paladar
13.
Sci Rep ; 7(1): 12205, 2017 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-28939879

RESUMO

Boar taint (BT) is an offensive odour or taste observed in pork from a proportion of non-castrated male pigs. Surgical castration is effective in avoiding BT, but animal welfare issues have created an incentive for alternatives such as genomic selection. In order to find candidate biomarkers, gene expression profiles were analysed from tissues of non-castrated pigs grouped by their genetic merit of BT. Differential expression analysis revealed substantial changes with log-transformed fold changes of liver and testis from -3.39 to 2.96 and -7.51 to 3.53, respectively. Co-expression network analysis revealed one module with a correlation of -0.27 in liver and three modules with correlations of 0.31, -0.44 and -0.49 in testis. Differential expression and co-expression analysis revealed candidate biomarkers with varying biological functions: phase I (COQ3, COX6C, CYP2J2, CYP2B6, ACOX2) and phase II metabolism (GSTO1, GSR, FMO3) of skatole and androstenone in liver to steroidgenesis (HSD17B7, HSD17B8, CYP27A1), regulation of steroidgenesis (STARD10, CYB5R3) and GnRH signalling (MAPK3, MAP2K2, MAP3K2) in testis. Overrepresented pathways included "Ribosome", "Protein export" and "Oxidative phosphorylation" in liver and "Steroid hormone biosynthesis" and "Gap junction" in testis. Future work should evaluate the biomarkers in large populations to ensure their usefulness in genomic selection programs.


Assuntos
Criação de Animais Domésticos/métodos , Redes Reguladoras de Genes/genética , Carne/análise , Redes e Vias Metabólicas/genética , Seleção Artificial/genética , Androsterona/análise , Androsterona/metabolismo , Animais , Biomarcadores/análise , Estudos de Viabilidade , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Fígado/química , Masculino , Odorantes/análise , Locos de Características Quantitativas/genética , Seleção Genética , Escatol/análise , Escatol/metabolismo , Sus scrofa/genética , Sus scrofa/metabolismo , Testículo/química , Testículo/metabolismo
14.
Talanta ; 169: 30-36, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28411818

RESUMO

Boar taint is a contemporary off-odor present in meat of uncastrated male pigs. As European Member States intend to abandon surgical castration of pigs by 2018, this off-odor has gained a lot of research interest. In this study, rapid evaporative ionization mass spectrometry (REIMS) was explored for the rapid detection of boar taint in neck fat. Untargeted screening of samples (n=150) enabled discrimination between sow, tainted and untainted boars. The obtained OPLS-DA models showed excellent classification accuracy, i.e. 99% and 100% for sow and boar samples or solely boar samples, respectively. Furthermore, the obtained models demonstrated excellent validation characteristics (R2(Y)=0.872-0.969; Q2(Y)=0.756-0.917), which were confirmed by CV-ANOVA (p<0.001) and permutation testing. In conclusion, in this work for the first time highly accurate and high-throughput (<10s) classification of tainted and untainted boar samples was achieved, rendering REIMS a promising technique for predictive modelling in food safety and quality applications.


Assuntos
Tecido Adiposo/química , Androsterona/análise , Análise de Alimentos/instrumentação , Ensaios de Triagem em Larga Escala/instrumentação , Espectrometria de Massas/instrumentação , Carne/análise , Tecido Adiposo/metabolismo , Animais , Análise de Alimentos/métodos , Ensaios de Triagem em Larga Escala/métodos , Humanos , Masculino , Espectrometria de Massas/métodos , Suínos
15.
PLoS One ; 12(4): e0174697, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28380041

RESUMO

While recent studies suggest an influence of noise on olfactory performance, it is unclear as to what extent the influence varies between subjects who are accustomed to noise and those who are not. Two groups of panelists were selected: a University panel usually working under silent conditions and an abattoir panel usually working on the slaughter line with abattoir noise. Odor discrimination, odor identification, and odor detection thresholds were studied. Furthermore, a sensory quality control task using 40 boar samples was performed. All tests were accomplished both with and without extraneous noise recorded at an abattoir (70 dB) using headphones. Contrary to the researchers' expectations, abattoir noise hardly affected the olfactory tests nor was the quality control task impaired. Abattoir noise did not influence the perceived intensity of boar taint and the classification results of the testers, regardless of whether they were accustomed to such noise or not. The results indicate that sensory quality control can be conducted in a manufacturing environment with constant noise without diminishing the assessors' performance.


Assuntos
Ruído/efeitos adversos , Olfato/fisiologia , Matadouros , Estimulação Acústica , Tecido Adiposo/química , Adulto , Androsterona/análise , Animais , Humanos , Masculino , Carne/normas , Pessoa de Meia-Idade , Odorantes , Projetos Piloto , Limiar Sensorial , Escatol/análise , Suínos
16.
Chem Biol Interact ; 276: 133-140, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28137513

RESUMO

3α-Hydroxysteroid dehydrogenase/carbonyl reductase (3α-HSD/CR) catalyzes the oxidation of androsterone with NAD+ to form androstanedione and NADH with the rate limiting step being the release of NADH. In this study, we elucidate the role of remote substrate binding interactions contributing to the rate enhancement by 3α-HSD/CR through steady-state kinetic studies with the truncated substrate analogs. No enzyme activity was detected for methanol, ethanol, and 2-propanol, which lack the steroid scaffold of androsterone, implying that the steroid scaffold plays an important role in enzyme catalytic specificity. As compared to cyclohexanol, the activity for 2-decalol, androstenol, and androsterone increases by 0.9-, 90-, and 200-fold in kcat, and 37-, 1.9 × 106-, and 1.8 × 106-fold in kcat/KB, respectively. The rate limiting step is hydride transfer for 3α-HSD/CR catalyzing the reaction of cyclohexanol with NAD+ based on the observed rapid equilibrium ordered mechanism and equal deuterium isotope effects of 3.9 on V and V/K for cyclohexanol. The kcat/KB value results in ΔG‡ of 14.7, 12.6, 6.2, and 6.2 kcal/mol for the 3α-HSD/CR catalyzed reaction of cyclohexanol, 2-decalol, androstenol, and androsterone, respectively. Thus, the uniform binding energy from the B-ring of steroids with the active site of 3α-HSD/CR equally contributes 2.1 kcal/mol to stabilize both the transition state and ground state of the ternary complex, leading to the similarity in kcat for 2-decalol and cyclohexanol. Differential binding interactions of the remote BCD-ring and CD-ring of androsterone with the active site of 3α-HSD/CR contribute 8.5 and 6.4 kcal/mol to the stabilization of the transition state, respectively. The removal of the carbonyl group at C17 of androsterone has small effects on catalysis. Both uniform and differential binding energies from the remote sites of androsterone compared to cyclohexanol contribute to the 3α-HSD/CR catalysis, resulting in the increases in kcat and kcat/KB.


Assuntos
Hidroxiesteroide Desidrogenases/metabolismo , Androsterona/análise , Androsterona/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Biocatálise , Domínio Catalítico , Cromatografia Líquida de Alta Pressão , Comamonas testosteroni/enzimologia , Deutério/química , Hidroxiesteroide Desidrogenases/química , Cinética , NAD/química , NAD/metabolismo , Oxirredução , Especificidade por Substrato , Espectrometria de Massas em Tandem , Termodinâmica
17.
Zoo Biol ; 36(2): 127-131, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28114737

RESUMO

The aim of this study was to determine whether concentrations of reproductive steroid hormone metabolites significantly differed between harem stallions and bachelor stallions in the free ranging group of Przewalski's horses (Equus ferus przewalskii) at the Hortobágy National Park in Hungary. Throughout the study, fecal samples were collected from 21 harem stallions and 15 bachelor stallions and analyzed for immunoreactive estrogen and androgen metabolites. Harem stallions demonstrated significantly higher concentrations of estrogen (P < 0.001) and epi-androsterone (P < 0.001), but not testosterone (P = 0.426). These findings confirm that sociosexual status has a significant effect on androgen concentrations in individual Przewalski stallions. Zoo Biol. 36:127-131, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Androsterona/análise , Estrogênios/análise , Fezes/química , Cavalos/fisiologia , Animais , Animais de Zoológico , Masculino
18.
J Steroid Biochem Mol Biol ; 165(Pt B): 212-218, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27328448

RESUMO

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.


Assuntos
Glucuronídeos/análise , Detecção do Abuso de Substâncias/métodos , Testosterona/análogos & derivados , Administração Oral , Androsterona/análise , Biomarcadores/análise , Cromatografia Líquida de Alta Pressão , Doping nos Esportes/prevenção & controle , Epitestosterona/análise , Etiocolanolona/análise , Cromatografia Gasosa-Espectrometria de Massas , Voluntários Saudáveis , Humanos , Hidrólise , Masculino , Reprodutibilidade dos Testes , Esteroides/análise , Espectrometria de Massas em Tandem , Testosterona/administração & dosagem , Testosterona/análise
19.
Meat Sci ; 123: 1-7, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27579788

RESUMO

Yeast inoculation of dry fermented sausages manufactured with entire male fat was evaluated as a strategy to improve sausage quality. Four different formulations with entire male/gilt back fat and inoculated/non-inoculated with Debaryomyces hansenii were manufactured. The use of entire male back fat produced the highest weight losses, hardness and chewiness in dry sausages. Consumers clearly distinguished samples according to drying time and D. hansenii inoculation while the use of entire/gilt back fat was not highly perceived. The presence of androstenone and skatole was close to their sensory thresholds. Androstenone was not degraded during the process but skatole was affected by yeast inoculation. D. hansenii growth on the surface regulated water release during ripening, reduced hardness and chewiness in entire male sausages and resulted with similar texture to gilt sausages. Yeast inoculation inhibited lipid oxidation providing fruity odours and less oxidized fatty sausages in the sensory analysis. The effectiveness of yeast to mask boar taint was demonstrated by sensory analysis.


Assuntos
Tecido Adiposo/química , Produtos da Carne/análise , Saccharomycetales , Leveduras , Adulto , Androsterona/análise , Cor , Comportamento do Consumidor , Dessecação , Gorduras na Dieta/análise , Feminino , Microbiologia de Alimentos , Qualidade dos Alimentos , Humanos , Lactobacillus , Masculino , Pessoa de Meia-Idade , Escatol/química , Olfato , Cloreto de Sódio na Dieta/análise , Staphylococcus , Paladar , Substâncias Reativas com Ácido Tiobarbitúrico/análise
20.
Drug Test Anal ; 8(11-12): 1204-1211, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27739243

RESUMO

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.


Assuntos
Anabolizantes/urina , Androsterona/urina , Isótopos de Carbono/urina , Cromatografia Líquida de Alta Pressão/métodos , Etiocolanolona/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Esteroides/análise , Testosterona/urina , Anabolizantes/química , Androsterona/análise , Androsterona/química , Cromatografia Gasosa , Doping nos Esportes , Etiocolanolona/análise , Etiocolanolona/química , Humanos , Espectrometria de Massas , Esteroides/química , Esteroides/metabolismo , Testosterona/análise
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