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1.
Drug Test Anal ; 12(11-12): 1544-1553, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32602999

RESUMO

Methylnortestosterone is a progestin and synthetic androgenic anabolic steroid, prohibited by WADA. Methylnortestosterone misuse is commonly detected by monitoring the parent compound and its main metabolites, 17α-methyl-5α-estrane-3α, 17ß-diol (M1) and 17α-methyl-5ß-estrane-3α, 17ß-diol (M2), in the glucuronide fraction. In the current study, a direct detection of methylnortestosterone sulfo-conjugated metabolites after ethyl acetate extraction and analysis by LC/Q/TOF-MS in negative ionization mode was performed, detecting two main sulfate metabolites (S1, S2). For the characterization of metabolites, samples from the excretion study, were additionally analyzed by GC-MS, after solvolysis and per TMS derivatization. RT and MS data collected, were compared with RT and MS data from metabolites of 17z-methyl-5α/ß-estrane-3α/ß, 17z-diols structures with prefixed stereochemistry at 3 and 5 positions, synthesized through Grignard reaction from 19-noretiocholanolone, 19-norandrosterone and 19-norepiandrosterone. Confirmed sulfate metabolites were S1, 17α-methyl-5α-estrane-3α, 17ß-diol 3α sulfate (detected up to 72 h) and S2, 17α-methyl-5ß-estrane-3α, 17ß-diol 3α sulfate (detected up to 192 h). Furthermore, applying targeted analysis based on RT and MS data of the synthesized metabolites two additional metabolites M3, 17ß-methyl-5ß-estrane-3α, 17α-diol and M4, 17ß-methyl-5α-estrane-3α, 17α-diol were detected in the glucuronide fraction and one more metabolite (S3) 17ß-methyl-5ß-estrane-3α, 17α-diol was detected in the sulfate fraction in lower abundance until the end of the excretion study (192 h). Interestingly, S2 could also be detected after the direct analysis of non-hydrolyzed steroid by GC-MS/MS as artifact, following normal ProcIV anabolic steroid procedure and using diethylether as extraction solvent.


Assuntos
Dopagem Esportivo/prevenção & controle , Estrenos/administração & dosagem , Estrenos/urina , Congêneres da Progesterona/administração & dosagem , Congêneres da Progesterona/urina , Detecção do Abuso de Substâncias/métodos , Administração Oral , Biomarcadores/urina , Dopagem Esportivo/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Gasosa-Espectrometria de Massas/normas , Humanos , Masculino , Pessoa de Meia-Idade , Detecção do Abuso de Substâncias/normas
2.
J Steroid Biochem Mol Biol ; 191: 105352, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30954508

RESUMO

Estrogen-receptor related receptors (ERRs) which consists of ERRα, ERRß and ERRγ belong to the orphan nuclear receptor subfamily 3, group B (NR3B) subfamily, and are constitutively active. ERRs have been shown to actively modulate estrogenic responses, and to play an essential role in pregnancy, and are implicated in breast cancer progression. Despite intensive efforts, no endogenous ligand other than the ubiquitous sterol, cholesterol which binds ERRα, has been identified for ERRs so far. The discovery of ligands that bind these orphan receptors will allow the manipulation of this pathway and may lead to novel strategies for the treatment of cancer and other diseases. We previously reported the identification of a novel endogenous estradienolone-like steroid (ED) that is strongly bound to sex hormone binding globulin, in pregnant women. Our recent results show that ED acts as an inverse agonist of ERRα and ERRγ by directly interacting with these receptors, and inhibiting their transcriptional activity. We also demonstrate that ED inhibits the growth of both estrogen receptor-positive (MCF-7) and estrogen receptor-negative (MDA-MB-231) breast cancer cells in a dose dependent manner, while of displaying a little effect on normal epithelial breast cells. Furthermore, the anti-mitogenic effect of ED in breast cancer cells is ERRα-dependent. These data suggest that ED-ERR interaction may represent a novel physiologically relevant hormone response pathway in the human. The finding that ED inhibits both ER negative and ER positive breast cancer cell growth may have important implications in pathophysiology breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Estrenos/metabolismo , Receptores de Estrogênio/metabolismo , Esteroides/metabolismo , Adulto , Antineoplásicos Hormonais/metabolismo , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/urina , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Agonismo Inverso de Drogas , Estrenos/farmacologia , Estrenos/urina , Feminino , Humanos , Gravidez , Mapas de Interação de Proteínas/efeitos dos fármacos , Esteroides/farmacologia , Esteroides/urina , Receptor ERRalfa Relacionado ao Estrogênio
3.
Int J Biol Markers ; 25(4): 185-94, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21161939

RESUMO

BACKGROUND: In preparation for large-scale epidemiologic studies of the role of estrogen metabolism in the etiology of breast and other cancers, we examined the stability of estrogens and estrogen metabolites (EM) in urine during processing and storage protocols. METHODS: Fifteen EM were measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS) in first morning urines from 3 premenopausal women. Linear regression was used to model log EM concentrations for each woman, with and without adding ascorbic acid (0.1% w/v), during storage at 4°C (7-8 time points, up to 48 hours), during long-term storage at -80°C (10 time points, up to 1 year), and by freeze-thaw cycles (up to 3). RESULTS: Without ascorbic acid, concentrations (pmol/mL) of nearly all EM changed <1% per 24 hours of storage at 4°C, and <1% during storage at -80°C for 1 year; similarly, thawing and refreezing samples 3 times was not consistently associated with losses for any EM. Ascorbic acid had no clear beneficial effect on EM stability in these experiments. CONCLUSIONS: Given the large inter-individual variability in urinary EM concentrations, changes of the magnitude observed here are unlikely to cause substantial misclassification. Furthermore, processing and storage conditions studied here are adequate for use in epidemiologic studies.


Assuntos
Estrogênios/urina , Ácido Ascórbico , Métodos Epidemiológicos , Estrenos/metabolismo , Estrenos/urina , Estrogênios/metabolismo , Feminino , Humanos , Pré-Menopausa , Preservação Biológica , Temperatura , Fatores de Tempo
4.
Anal Chim Acta ; 586(1-2): 196-207, 2007 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-17386712

RESUMO

For almost two decades we have known that enzymatic hydrolysis of "normal" urine samples from the entire male horse using Escherichia coli (E. coli) followed by solvolysis (ethyl acetate:methanol:sulphuric acid) results in the detection of significant amounts of estr-4-ene-3,17-dione (19-norandrost-4-ene-3,17-dione) along with estr-4-en-17beta-ol-3-one (19-nortestosterone, nandrolone) in extracts of the hydrolysed urine and that both steroids are isolated from the solvolysis fraction. This solvolysis process is targeted at the steroid sulphates. Also we have shown that 19-norandrost-4-ene-3,17-dione and 19-nortestosterone are isolated from testicular tissue extracts. Subsequently, evidence was obtained that 19-nortestosterone detected in extracts of "normal" urine from male horses may not be derived from the 17beta-sulphate conjugate. However, following administration of 19-nortestosterone based proprietary anabolic steroids to all horses (males, females and castrates), the urinary 19-nortestosterone arising from the administration is excreted primarily as the 17beta-sulphate conjugate. Thus, if the 19-nortestosterone-17beta-sulphate conjugate arises only following administration this has interesting implications for drug surveillance programmes to control administration of 19-nortestosterone based anabolic preparations to male horses. These results have led us to consider that the precursors to 19-nortestosterone and 19-norandrost-4-ene-3,17-dione, present in the urine prior to the hydrolysis steps, have the same basic structure except for the functionality at the 17-position. We have used preparative high pressure liquid chromatography (LC) and LC fractionation to separate these precursors from the high amounts of oestrogenic sulphates present in "normal" urine from the entire male horse. Purified fractions have then been studied by liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) to identify the precursors.


Assuntos
Técnicas de Química Analítica/métodos , Estrenos/urina , Nandrolona/urina , Esteroides/química , Esteroides/urina , Urinálise/métodos , Acetatos/química , Animais , Escherichia coli/metabolismo , Estrenos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cavalos , Concentração de Íons de Hidrogênio , Hidrólise , Masculino , Nandrolona/análise , Oximas/química , Esteroides/análise , Testículo/metabolismo
5.
J Steroid Biochem Mol Biol ; 104(1-2): 85-91, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17208439

RESUMO

Rules of horse racing stipulate that pregnant mares may compete under definite conditions of date, because early pregnant status may be misused for the sake of enhancing physical performance by putative anabolic steroid action. Screening for pregnancy is generally performed by plasma equine gonadotrophin (eCG) immunoassay, which covers the period between Days 40 and 120. In common screening for urinary anabolic steroids performed by gas chromatography-mass spectrometry, inclusion of two complementary criteria, i.e. the evaluation of total conjugates of 5(10)-estrene-3beta,17alpha-diol (EED) and estrone (E1), can easily be performed. Although EED and E1 have no anabolic property per se in the horse, assessing these two markers may be helpful in the period comprised between Days 70 and 250, thereby prolonging the detection period behind that of eCG. Peak values of EED and E1 are then attained, so that visual inspection of chromatographic tracings remains in general sufficient as a diagnostic tool. Comparison of EED and E1 during pregnancy and in an estrus cycle indicates a drastic difference in the attained excretion values, attributable to either the placenta or the ovarian follicle. The identity of EED has been proven by GC-MS(n) in urine and in placental tissue.


Assuntos
Anabolizantes/urina , Estrenos/urina , Estrona/urina , Cavalos/urina , Animais , Dopagem Esportivo , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Placenta , Gravidez
6.
J Chromatogr ; 564(2): 485-92, 1991 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-1874853

RESUMO

The urinary excretion and metabolic pattern of 17 beta-trenbolone, a synthetic anabolic steroid hormone used as a growth promotor for beef cattle in several countries, has been studied in a human subject. For the separation of the metabolites of 17 beta-trenbolone, a reversed-phase high-performance liquid chromatographic method was established. The method was tested with metabolites obtained from incubation of 17 beta-trenbolone with rat liver microsomes. Fifteen metabolites could be well separated in one run by using a concave acetonitrile-water-methanol gradient. After ingestion of the tracer-labelled hormone at a dose of 0.04 mg/kg body weight 54% of the administered radioactivity was found in the urine after 26 h and 63% after 72 h. Of the urinary material 54% was present as glucuronides, which contained mostly 17 alpha-trenbolone, 17 beta-trenbolone and trendione. At least five other polar metabolites, presumably hydroxylated products, were found in smaller amounts, mostly in the unconjugated and sulphated fractions. Thus, the disposition of 17 beta-trenbolone in humans differs significantly from that in rats, which may have a bearing on the toxicological evaluation of the hormone.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Acetato de Trembolona/urina , Animais , Estrenos/urina , Glucuronatos/urina , Humanos
7.
J Chromatogr ; 489(1): 235-43, 1989 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-2663905

RESUMO

Immunoassays are often used for the screening of anabolic residues in edible tissues and excreta (urine, faeces) from inspected animals. Radioimmunoassays have been used for ten years for the determination in biological samples of the main natural and synthetic anabolic estrogens and androgens. In order to simplify the sample preparation and analysis and to reduce the cost, competitive enzyme immunoassays (EIA) were developed for the main synthetic anabolics used illegally in livestock fattening. EIA are based on a competition between the analyte (hormone or metabolite) and the enzyme-labelled hormone for binding to specific antibodies immobilized in wells of a microtitration plate. Two enzymes were evaluated: horseradish peroxidase (HRP) and Bacillus licheniformis beta-lactamase (BLL) using hydrogen peroxide-o-phenylenediamine or benzylpenicillin-starch-iodine as substrates, respectively. The same derivative was used for chemical coupling of the hormone to enzyme (tracer preparation) and to bovine serum albumin to produce specific antibodies in rabbits. Hormone doses that inhibited 50% of the tracer (HRP-hormone) binding to antibody (ID50) were 18, 8, 6 and 11 pg per well for diethylstilbestrol, nortestosterone, methyltestosterone and trenbolone, respectively. These values were lower than those observed in RIA. The reproducibility and accuracy of EIA in urine analysis were similar to those of RIA. Very small amounts of urine were needed (2.5 microliters). This simple method may require less than 2 h. With the BLL-hormone tracer, the enzymatic activity remaining in the wells and hence the hormone content of the sample could be estimated with the naked eye using benzylpenicillin-starch-iodine as substrate.


Assuntos
Dietilestilbestrol/urina , Estrenos/urina , Metiltestosterona/urina , Nandrolona/urina , Acetato de Trembolona/urina , Animais , Bovinos , Fenômenos Químicos , Química , Técnicas Imunoenzimáticas , Radioimunoensaio
8.
J Chromatogr ; 445(2): 385-92, 1988 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-3215986

RESUMO

An high-performance liquid chromatography (HPLC)-thin-layer chromatography (TLC) method was developed to detect the illegal use of the xenobiotic growth promotor Trenbolone acetate (TBA). Very effective clean-up of bovine urine was achieved by immunoaffinity chromatography (IAC). The active form of TBA, the steroid 17 beta-Trenbolone (17 beta-TB), as well as its major metabolite 17 alpha-Trenbolone (17 alpha-TB), were assayed simultaneously with HPLC and on-line UV detection. The fraction containing 17 alpha-TB and 17 beta-TB (TB-fraction) was collected, and for confirmation 17 beta- and 17 alpha-TB were subsequently separated and identified by TLC. The limit of detection by on-line HPLC-UV (350 nm) was 1-2 micrograms TB/l. Off-line TLC detection was even more sensitive, 0.5 microgram 17 beta- or 17 alpha-TB/1. The assay was validated by investigating urine samples from veal calves implanted with TBA. The presence of 17 beta- and 17 alpha-TB was clearly demonstrated. A survey of the illegal use of TBA in cattle was performed by applying the assay to urine obtained at slaughter. No residues of TBA or its metabolites were found in any of the 144 random samples from the Dutch public health surveillance programme.


Assuntos
Estrenos/urina , Acetato de Trembolona/urina , Animais , Bovinos , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Implantes de Medicamento , Géis , Imunoglobulina G/análise , Masculino , Espectrometria de Fluorescência , Acetato de Trembolona/administração & dosagem , Acetato de Trembolona/efeitos adversos
9.
C R Acad Sci III ; 306(2): 39-41, 1988.
Artigo em Francês | MEDLINE | ID: mdl-3126986

RESUMO

Levels of testosterone, trenbolone, 17 beta-estradiol (conjugated plus unconjugated) and creatinine were measured in urine of calves treated 55 days before with trenbolone and 17 beta-estradiol implants. The mean concentration of urinary creatinine and implant steroids was increased by a factor 3 after 1 day of total diet and 5 after 2 days, levels of individual calves exhibiting a great dispersion.


Assuntos
Creatinina/urina , Dieta , Estradiol/urina , Estrenos/urina , Testosterona/urina , Acetato de Trembolona/urina , Animais , Bovinos , Implantes de Medicamento , Estradiol/administração & dosagem , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Radioimunoensaio , Testosterona/administração & dosagem , Acetato de Trembolona/administração & dosagem
11.
Biomed Mass Spectrom ; 11(2): 96-9, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6547065

RESUMO

As part of a continuing research program associated with the detection of anabolic steroid residues in horse urine, normal samples from entire male horses have now been investigated. Isomers of three C-18 neutral steroids; 4-estren-17-ol-3-one (1), estrane-3,17-diol (2) and an unsaturated estranediol having a possible structure (3), have been identified in urine samples from two male horses aged 8 and 14 years. Of these three steroids, compound (2) was not detected in the urine of a 2.5 yr old entire male nor in the majority of post-race urine samples from entire male horses average age 3.8 yrs (n = 34). Ten of these samples showed tentative indications of this compound. Although the isolation of isomers of estrane-3,17-diol from human non-pregnancy urine has been reported previously, analysis of non-pregnancy urine samples in the present study did not reveal the presence of these compounds.


Assuntos
Cavalos/urina , Esteroides/urina , Animais , Estranos/urina , Estrenos/urina , Masculino , Espectrometria de Massas/métodos , Nandrolona/urina
12.
Experientia ; 36(4): 394-5, 1980 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-7189716

RESUMO

The development of a radioimmunoassay method for the detection of trienbolone is described. It is dependent on antibody raised against a bovine serum albumin conjugate of trienbolone 17-hemisuccinate in sheep.


Assuntos
Estrenos/urina , Acetato de Trembolona/urina , Animais , Anticorpos , Reações Cruzadas , Humanos , Radioimunoensaio/métodos , Ovinos/imunologia
13.
Xenobiotica ; 8(4): 197-206, 1978 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-645104

RESUMO

1. Cross-bred and thoroughbred geldings were injected with veterinary doses of various synthetic anabolic steroids. Urines collected sequentially from treated animals were analysed, following solvent extraction, by radioimmunoassay using 19-[3H]nortestosterone and an antibody raised against a 19-nortestosterone immunogen. 2. Urinary excretion of 19-nortestosterone and/or its cross-reacting metabolites was detectable for various times after administration of different nortestosterone esters, as follows: phenylpropionate (400 mg), greater than 14 days; cyclohexylpropionate (100 mg), greather than 10 days; laurate (200 mg) greater than 50 days. After administration of the parent steroid (150 mg) cross-reacting compounds were detectable in urine for ca. 3 days. 3. Urinary excretion of esters of other anabolic steroids cross-reacting with the 19-nortestosterone antibody (e.g. 1-dehydrotestosterone and trienbolone) could also be followed by analysing solvent extracts of urines by the radioimmunoassay. Cross-reacting compounds in urine after administration of 1-dehydrotestosterone undecylenate (250 mg) and trienbolone acetate (75 mg) could be detected for greater than 35 days and greather than 5 days, respectively.


Assuntos
Anabolizantes/urina , Estrenos/urina , Cavalos/urina , Animais , Reações Cruzadas , Masculino , Métodos , Nandrolona/análogos & derivados , Nandrolona/urina , Radioimunoensaio , Testosterona/análogos & derivados , Testosterona/imunologia , Testosterona/urina , Fatores de Tempo
14.
Clin Genet ; 9(2): 234-44, 1976 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1248181

RESUMO

Two kindreds with Marinesco-Sjögren's syndrome in three sibships are described. In five of the six affected, but in none of the unaffected sibs, a hypergonadotropic hypogonadism was observed. In one of the kindreds a high degree of inbreeding was revealed, and inbreeding likely also existed in the other kindred. The two families were not related. Marinesco-Sjögren's syndrome is known to be a distinct clinical entity, governed by autosomal recessive inheritance, and this also applies to hypergonadotropic hypogonadism. Several heredo-degenerative nervous disorders are accompanied by a hypogonadotropic hypogonadism, which is believed to be secondary to the neurological disorder, as in traumatic paraplegia. A hypergonadotropic hypoganadism cannot readily be explained in this way. We consider genetic linkage between two independent disorders as the most likely explanation for the observed concurrence.


Assuntos
Ataxia Cerebelar/genética , Hipogonadismo/genética , Adolescente , Adulto , Androstenóis/urina , Ataxia Cerebelar/urina , Estrenos/urina , Etiocolanolona/urina , Feminino , Ligação Genética , Humanos , Hipogonadismo/urina , Masculino , Linhagem
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