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1.
Drug Test Anal ; 13(3): 550-557, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33142032

RESUMO

The interpretation of the steroidal module of the Athlete Biological Passport (ABP) in female athletes is complex due to the large variation of the endogenous urinary steroids. The menstrual cycle seems to be one of the largest confounders of the steroid profile. The duration of the different phases in the menstrual cycle differs between women and is difficult to predict only by counting days after menstruation. Here, we have determined the follicle, ovulation, and luteal phases, by assessing the menstrual hormones in serum samples collected from 17 healthy women with regular menses. Urine samples were collected three times per week during two consecutive cycles to measure the urinary steroid concentrations used in the ABP. The metabolite that was mostly affected by the menstrual phases was epitestosterone (E), where the median concentration was 133% higher in the ovulation phase compared to the follicle phase (p < 0.0001). The women with a large coefficient of variation (CV) in their first cycle also had a large CV in their second cycle and vice versa. The inter-individual difference was extensive with a range of 11%-230% difference between the lowest and the highest T/E ratio during a cycle. In conclusion, E and ratios with E as denominator are problematic biomarkers for doping in female athletes. The timing of the sample collection in the menstrual cycle will have a large influence on the steroid profile. The results of this study highlight the need to find additional biomarkers for T doping in females.


Assuntos
Epitestosterona/urina , Hormônios/urina , Ciclo Menstrual/urina , Esteroides/urina , Adulto , Atletas , Biomarcadores/sangue , Biomarcadores/urina , Doping nos Esportes/prevenção & controle , Epitestosterona/sangue , Feminino , Hormônios/sangue , Humanos , Ciclo Menstrual/sangue , Ciclo Menstrual/fisiologia , Esteroides/sangue , Detecção do Abuso de Substâncias/métodos
2.
J Forensic Sci ; 59(4): 1025-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24611438

RESUMO

Anabolic-androgenic steroids (AASs) are frequently misused. To determine causes of death, characteristics, toxicology, and pathology of AAS positive cases, all cases (n = 24) presenting to the New South Wales Department of Forensic Medicine (1995-2012) were retrieved. All were male, and the mean age was 31.7 years. Deaths were mainly due to accidental drug toxicity (62.5%), then suicide (16.7%) and homicide (12.5%). Abnormal testosterone/epitestosterone ratios were reported in 62.5%, followed by metabolites of nandrolone (58.3%), stanozolol (33.3%), and methandienone (20.8%). In 23 of 24 cases, substances other than steroids were detected, most commonly psychostimulants (66.7%). In nearly half, testicular atrophy was noted, as was testicular fibrosis and arrested spermatogenesis. Left ventricular hypertrophy was noted in 30.4%, and moderate to severe narrowing of the coronary arteries in 26.1%. To summarize, the typical case was a male polydrug user aged in their thirties, with death due to drug toxicity. Extensive cardiovascular disease was particularly notable.


Assuntos
Anabolizantes/efeitos adversos , Androgênios/efeitos adversos , Homicídio , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Suicídio , Adulto , Anabolizantes/sangue , Anabolizantes/urina , Androgênios/sangue , Androgênios/urina , Atrofia , Estenose Coronária/patologia , Epitestosterona/sangue , Epitestosterona/urina , Humanos , Hipertrofia Ventricular Esquerda/patologia , Masculino , Metandrostenolona/sangue , Metandrostenolona/urina , Pessoa de Meia-Idade , Nandrolona/sangue , Nandrolona/urina , New South Wales/epidemiologia , Estanozolol/sangue , Estanozolol/urina , Transtornos Relacionados ao Uso de Substâncias/sangue , Transtornos Relacionados ao Uso de Substâncias/urina , Testículo/patologia , Testosterona/sangue , Testosterona/urina , Adulto Jovem
3.
Horm Behav ; 61(1): 147-55, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21983229

RESUMO

Testosterone and other anabolic-androgenic steroids enhance athletic performance in men and women. As a result, exogenous androgen is banned from most competitive sports. However, due to variability in endogenous secretion, and similarities with exogenous testosterone, it has been challenging to establish allowable limits for testosterone in competition. Endogenous androgen production is dynamically regulated by both exercise and winning in competition. Furthermore, testosterone may promote athletic performance, not only through its long-term anabolic actions, but also through rapid effects on behavior. In women, excess production of endogenous testosterone due to inborn disorders of sexual development (DSD) may convey a competitive advantage. For many years, female competitors have been subject to tests of sexual genotype and phenotype known as gender verification. Although gender verification has not identified any normal man competing as a woman, this process has identified women athletes with DSD. As understanding of DSD has expanded in recent years, women with DSD are increasingly able to continue athletic competition.


Assuntos
Desempenho Atlético , Testosterona/fisiologia , Anabolizantes/farmacologia , Doping nos Esportes/métodos , Epitestosterona/biossíntese , Epitestosterona/sangue , Epitestosterona/farmacologia , Feminino , Humanos , Masculino , Aberrações dos Cromossomos Sexuais , Análise para Determinação do Sexo/métodos , Diferenciação Sexual , Testosterona/biossíntese , Testosterona/metabolismo , Testosterona/farmacocinética , Testosterona/farmacologia
4.
Pharmacogenet Genomics ; 21(6): 325-32, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21383644

RESUMO

OBJECTIVE: To study the disposition of serum testosterone and seven of its metabolites before and after 2 days of an intramuscular dose (500 mg) of testosterone enanthate in relation to the phosphodiesterase (PDE7B) and the uridine 5'-diphospho-glucuronosyltransferase (UGT2B17) genotypes. METHODS: Patients were genotyped for UGT2B17 deletion polymorphism and single nucleotide polymorphisms in the PDE7B gene. The involvement of PDE7B in hydrolysis of enanthate was assessed in human liver homogenates. RESULTS: Genetic variation in the PDE7B gene was found to be associated with the serum level of testosterone. Individuals homozygous for PDE7B rs7774640 G allele had a smaller increase (2.5-fold) in the serum testosterone levels compared with carriers of the A allele (3.9-fold, P=0.0006). In addition, genetic variation in the PDE7B gene significantly influences the testosterone/epitestosterone ratio, a biomarker of testosterone doping. Our in-vitro incubation studies confirmed that PDE7B serves as a catalyst of the hydrolysis of testosterone enanthate. The UGT2B17 deletion polymorphism did not show any significant association with serum testosterone levels or the other androgen metabolites investigated. CONCLUSION: We have shown that PDE7B is involved in the hydrolysis of testosterone enanthate and that genetic variation in the PDE7B gene is a determinant of the systemic levels of testosterone after administration of testosterone enanthate. It is reasonable to believe that the genetic variation in testosterone bioavailability may be correlated to varying effects of this androgen, whether it is used for replacement therapy or abused in doping. Thus our results may be important to consider in doping test programmes and in therapeutics with androgens and other esterified drugs.


Assuntos
Androgênios/farmacocinética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 7/genética , Glucuronosiltransferase/genética , Polimorfismo Genético/genética , Testosterona/análogos & derivados , Adolescente , Adulto , Epitestosterona/sangue , Deleção de Genes , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Antígenos de Histocompatibilidade Menor , Testosterona/sangue , Testosterona/farmacocinética , Distribuição Tecidual , Adulto Jovem
5.
Gen Comp Endocrinol ; 170(1): 92-8, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20888823

RESUMO

Testosterone regulates a wide variety of behavioral and physiological traits in male vertebrates. It influences reproductive and aggressive behaviors and is used as a marker of gonadal activity. While testosterone is the primary biologically active male gonadal steroid in the blood, it is metabolized into a variety of related steroids when excreted via urine and feces. To monitor endocrinological profiles studies on wild-living animals primarily rely on non-invasively collected samples such as urine or feces. Since a number of androgen metabolites that are found in high concentrations in these matrices do not stem exclusively from gonadal production, but are also produced by the adrenal cortex, the metabolism and excretion pattern of testosterone and its characteristic metabolites have to be investigated. Here, we compare the levels of 11 androgens and their metabolites in serum and urine (after hydrolytic/solvolytic cleavage of conjugates) from female, and intact and castrated male chimpanzees to investigate whether they were of testicular or adrenal origin. For serum, significant differences in concentrations were found only for native testosterone. For urine, testosterone concentrations showed the largest differences between intact and castrated males, and intact males and females, while no differences were seen between females and castrated males. Epitestosterone levels revealed the same pattern. These differences in urinary concentrations could also be seen for 5α-androstane-3α,17ß-diol (androstanediol), and less clearly for 5α-dihydrotestosterone (5α-DHT), etiocholanolone, and androsterone. In urine of males, significant correlations were found between the levels of testosterone and 5α-androstane-3α,17ß-diol, as well as between testosterone and epitestosterone. Therefore, the clearest urinary markers of gonadal activity in male chimpanzees seems to be testosterone itself.


Assuntos
Androgênios/sangue , Androgênios/urina , Androgênios/metabolismo , Androsterona/sangue , Androsterona/urina , Animais , Di-Hidrotestosterona/sangue , Di-Hidrotestosterona/urina , Epitestosterona/sangue , Epitestosterona/urina , Feminino , Masculino , Testosterona/sangue , Testosterona/urina
6.
J. physiol. biochem ; 66(2): 137-142, jun. 2010. tab
Artigo em Inglês | IBECS | ID: ibc-122837

RESUMO

No disponible


Previous studies with different results have suggested that total and bioavailable testosterone levels are modified by physical exercise. Such changes may be related to modifications in cortisol levels and could be reflected in some urine androgens. To determine how weight lifting training may affect serum and urinary androgens, we measured total serum testosterone (T), cortisol, sex hormonebinding globulin (SHBG) and urinary testosterone, epitestosterone, androsterone, and etiocholanolone, in a group of 19 elite weight lifters after 20 weeks of training. SHBG increased (from 27.5 ± 9.5 to 34.7 ± 8.1 nM, p < 0.05) whereas T/SHBG decreased significantly (from 1.10 ± 0.4 to 0.85 ± 0.3, p < 0.05). Serum total testosterone and cortisol did not change significantly. In urine, androsterone and etiocholanolone decreased significantly, whereas testosterone and epitestosterone remained unchanged. Changes in T/SHBG were related positively with changes in urinary androgens (r = 0.680, p < 0.01), and changes in SHBG were negatively related with changes in urinary androgens (r = −0.578, p < 0.01). These results suggest that intense physical activity may have an influence on the elimination of androgenic hormones due mainly to changes in their transporting protein SHBG (AU)


Assuntos
Humanos , Androgênios/urina , Globulina de Ligação a Hormônio Sexual/fisiologia , Atividade Motora/fisiologia , Testosterona/sangue , Epitestosterona/sangue , Androsterona/sangue , Etiocolanolona/sangue , Proteínas de Transporte , Esportes/fisiologia , Levantamento de Peso/fisiologia
7.
Forensic Sci Int ; 184(1-3): e7-11, 2009 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-19110387

RESUMO

The use of anabolic androgenic steroids (AAS) has been associated with different adverse effects, some of which potentially lethal. Most users of AAS are male, but the prevalence of such use appears to be increasing in females. Here we present a sudden unexpected death in a female fitness athlete with a possible connection to use of doping agents.


Assuntos
Estimulantes do Sistema Nervoso Central/sangue , Morte Súbita/etiologia , Doping nos Esportes , Efedrina/sangue , Fenilpropanolamina/sangue , Simpatomiméticos/sangue , Glândulas Suprarrenais/patologia , Adulto , Anabolizantes/urina , Estimulantes do Sistema Nervoso Central/efeitos adversos , Efedrina/efeitos adversos , Epitestosterona/sangue , Feminino , Toxicologia Forense , Ventrículos do Coração/patologia , Humanos , Pulmão/patologia , Miocárdio/patologia , Fenilpropanolamina/efeitos adversos , Estanozolol/urina , Simpatomiméticos/efeitos adversos , Testosterona/análogos & derivados , Testosterona/urina
8.
Steroids ; 72(4): 375-80, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17368496

RESUMO

Androgens are considered to play a substantial role in pathogenesis of both benign prostatic hyperplasia (BPH) and prostate cancer. The importance of determination of androgen levels in tissue and serum for cancer progression and prognosis has been poorly understood. The aim of study was to find out hormonal differences in both diseases, their correlations between intraprostatic and serum levels and predicted value of their investigation. Testosterone, dihydrotestosterone, androstenedione and also epitestosterone were determined in prostate tissue from 57 patients who underwent transvesical prostatectomy for BPH and 121 patients after radical prostatectomy for prostate cancer. In 75 subjects with cancer and 51 with BPH the serum samples were analyzed for testosterone, dihydrotestosterone and SHBG. Significantly higher intraprostatic androgen concentrations, i.e. 8.85+/-6.77 versus 6.44+/-6.43 pmol/g, p<0.01 for dihydrotestosterone, and 4.61+/-7.02 versus 3.44+/-4.53 pmol/g, p<0.05 for testosterone, respectively, were found in patients with prostate cancer than in BPH. Higher levels in cancer tissue were found also for epitestosterone. However, no differences were found in serum levels. Highly significant correlations occurred between all pairs of intraprostatic androgens and also epitestosterone as well as between serum testosterone and dihydrotestosterone (p<0.001) in both BPH and cancer groups. Correlation was not found between corresponding tissue and serum testosterone and dihydrotestosterone, either in benign or cancer samples. The results point to importance of intraprostatic hormone levels for evaluation of androgen status of patients, contrasting to a low value of serum hormone measurement.


Assuntos
Androgênios/metabolismo , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/metabolismo , Idoso , Idoso de 80 Anos ou mais , Androgênios/sangue , Epitestosterona/sangue , Epitestosterona/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/sangue , Hiperplasia Prostática/cirurgia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/cirurgia
9.
Clin Endocrinol (Oxf) ; 66(1): 123-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17201811

RESUMO

OBJECTIVE: A diurnal variation in serum testosterone in adult men is well recognized, but whether this occurs during exogenous testosterone administration and the degree to which it is endogenous to the testis is unclear. DESIGN: A clinical research centre investigation of testicular function in normal men. PATIENTS: Twenty normal men were recruited, 10 of whom were investigated during administration of testosterone with etonogestrel to suppress gonadotrophin secretion. MEASUREMENTS: Hourly blood samples were taken over 24 h for measurement of testosterone, inhibin B, LH, FSH and cortisol. Urinary excretion of testosterone and the testicular steroid epitestosterone was also measured. RESULTS: In the controls, a diurnal variation in serum testosterone and LH but not FSH was detected. The treated group had similar testosterone concentrations but showed no diurnal variation. Periodicity was also detected in inhibin B concentrations in 5 of the controls and in 9 of the treated group, who also showed synchrony not seen in the controls. Both groups showed diurnal variation in cortisol. Urinary testosterone excretion did not show a diurnal variation in either group, but this was apparent for epitestosterone with a morning peak in both groups despite the markedly lower excretion in the treated men. CONCLUSIONS: The diurnal variation of testosterone in normal men is due to a change in secretion rather than in clearance and is largely LH driven. An endogenous rhythm in both testicular steroidogenesis (epitestosterone) and Sertoli cell function (inhibin B) is also present.


Assuntos
Ritmo Circadiano , Desogestrel/farmacologia , Gonadotropinas/antagonistas & inibidores , Hormônios Testiculares/sangue , Adulto , Análise de Variância , Estudos de Casos e Controles , Epitestosterona/sangue , Epitestosterona/urina , Hormônio Foliculoestimulante/sangue , Humanos , Hidrocortisona/sangue , Inibinas/sangue , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Globulina de Ligação a Hormônio Sexual/análise , Hormônios Testiculares/urina , Testosterona/sangue , Testosterona/farmacologia , Testosterona/urina
10.
Clin Chem Lab Med ; 43(2): 221-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15843221

RESUMO

Twenty-one healthy male volunteers aged 20-70 years were given transdermally 25 mg of 7-oxo-dehydroepiandrosterone daily in the form of an emulgel for 8 consecutive days. Morning blood was collected as follows: before application, and after the first, fourth and eighth doses (days 0, 2, 5 and 9), and then at different time intervals after termination of the treatment (days 16, 23, 37, 51, 72 and 100). Cortisol, testosterone, epitestosterone, estradiol, dehydroepiandrosterone and its sulfate, 7alpha- and 7beta-hydroxy-dehydroepiandrosterone, luteinizing hormone, follicle-stimulating hormone and sex hormone-binding globulin were measured in blood sera. In the course of treatment 7beta-hydroxy-dehydroepiandrosterone was significantly increased; testosterone and gonadotropins were lowered, but only after the first dose. All other significant changes were observed during the period after termination of the application:7beta-hydroxy-dehydroepiandrosterone remained increased for 28 days, 7alpha-hydroxy-dehydroepiandrosterone, testosterone, estradiol and sex hormone-binding globulin were decreased as late as day 63 and 91, respectively. On the other hand, epitestosterone was significantly increased between days 23 and 100. The levels of all other parameters studied were not significantly changed. The study points to an immediate as well as delayed effect of the short-term transdermal application of 7-oxo-dehydroepiandrosterone on relevant hormonal parameters.


Assuntos
Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/administração & dosagem , Desidroepiandrosterona/farmacologia , Administração Cutânea , Adulto , Idoso , Desidroepiandrosterona/sangue , Desidroepiandrosterona/metabolismo , Epitestosterona/sangue , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Gonadotropinas/sangue , Humanos , Hidrocortisona/sangue , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue , Fatores de Tempo
11.
Hum Reprod ; 19(11): 2658-67, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15333595

RESUMO

BACKGROUND: Combined testosterone and progestogen preparations are a promising approach to male hormonal contraception. We investigated the effect of s.c. etonogestrel with depot testosterone on spermatogenesis in normal men over a period of 48 weeks. METHODS: Fifteen healthy men received three s.c. 68 mg etonogestrel implants. Testosterone pellets (400 mg) were administered at 12 weekly intervals. RESULTS: Nine men completed 48 weeks of treatment. Four subjects chose to discontinue after 6 months, one man withdrew from the study early for personal reasons and one was withdrawn due to illness. Sperm concentrations of <1 x 10(6)/ml were achieved in all men by 16 weeks of treatment. All men became azoospermic, although the time to achieve this varied from 8 to 28 weeks. Azoospermia was maintained in eight of the nine men treated for 48 weeks, one subject showing partial recovery from 40 weeks. Testosterone levels remained in the physiological range throughout. Treatment did not result in weight gain, change in body composition or decline in high-density lipoprotein cholesterol concentrations. CONCLUSIONS: The combination of three etonogestrel implants with depot testosterone results in rapid and consistent suppression of spermatogenesis. This can be maintained for up to 1 year and may therefore be a suitable approach for a long-acting male hormonal contraceptive.


Assuntos
Anticoncepcionais Masculinos/administração & dosagem , Anticoncepcionais Masculinos/efeitos adversos , Desogestrel/administração & dosagem , Desogestrel/efeitos adversos , Oligospermia/induzido quimicamente , Testosterona/administração & dosagem , Testosterona/efeitos adversos , Adolescente , Adulto , Composição Corporal/efeitos dos fármacos , Desogestrel/sangue , Relação Dose-Resposta a Droga , Implantes de Medicamento , Epitestosterona/sangue , Epitestosterona/urina , Hormônio Foliculoestimulante/sangue , Hemoglobinas/análise , Humanos , Inibinas/sangue , Lipídeos/sangue , Hormônio Luteinizante/sangue , Masculino , Oligospermia/metabolismo , Comportamento Sexual/efeitos dos fármacos , Contagem de Espermatozoides , Espermatogênese/efeitos dos fármacos , Testosterona/sangue
12.
J Clin Endocrinol Metab ; 87(5): 2225-31, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11994368

RESUMO

Epitestosterone has been demonstrated to act at various levels as a weak antiandrogen. So far, its serum levels have been followed up only in males. Epitestosterone and its major circulating precursor pregnenolone sulfate and T were measured in serum from 211 healthy women and 386 men to find out whether serum concentrations of epitestosterone are sufficient to exert its antiandrogenic actions. In women, epitestosterone exhibited a maximum around 20 yr of age, followed by a continuous decline up to menopause and by a further increase in the postmenopause. In men, maximum epitestosterone levels were detected at around 35 yr of age, followed by a continuous decrease. Pregnenolone sulfate levels in women reached their maximum at about age 32 yr and then declined continuously, and in males the maximum was reached about 5 yr earlier and then remained nearly constant. Epitestosterone correlated with pregnenolone sulfate only in males. In both sexes a sharp decrease of the epitestosterone/T ratio around puberty occurred. In conclusion, concentrations of epitestosterone and pregnenolone sulfate are age dependent and, at least in prepubertal boys and girls, epitestosterone reaches or even exceeds the concentrations of T, thus supporting its role as an endogenous antiandrogen. The dissimilarities in the course of epitestosterone levels through the lifespan of men and women and its relation to pregnenolone sulfate concentrations raise the question of the contribution of the adrenals and gonads to the production of both steroids and even to the uniformity of the mechanism of epitestosterone formation.


Assuntos
Envelhecimento/sangue , Epitestosterona/sangue , Pregnenolona/sangue , Caracteres Sexuais , Testosterona/sangue , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Valores de Referência
13.
Steroids ; 66(1): 55-7, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11090659

RESUMO

The risk of breast cancer is 2 to 5 times higher in patients suffering from gross cystic disease. Breast cysts are categorized into two groups (type I and type II) according to the concentration of electrolytes in the cyst fluid. The two types also differ with respect to accumulation of steroids and steroidogenic enzyme activity. In type I cysts a higher risk of breast carcinoma could be expected. Here, we studied a possible relationship between the type of cyst and levels of epitestosterone (an endogenous antiandrogen), allopregnanolone (a product of 5alpha-reductase activity), and pregnenolone-sulfate (an activator of N-methyl-D-asparate receptors). We have found five times higher levels of epitestosterone in BCF in comparison with the circulation. Allopregnanolone levels were similar to those in plasma of women in the luteal phase of the menstrual cycle. Pregnenolone-sulfate levels in BCF were about two orders of magnitude higher when compared with the circulation. No differences were found in concentrations of the steroids studied between the types of cysts.


Assuntos
Epitestosterona/metabolismo , Exsudatos e Transudatos/metabolismo , Doença da Mama Fibrocística/metabolismo , Pregnanolona/metabolismo , Pregnenolona/metabolismo , Adulto , Epitestosterona/sangue , Feminino , Humanos , Fase Luteal/fisiologia , Pessoa de Meia-Idade , Pregnanolona/sangue , Pregnenolona/sangue , Valores de Referência
14.
Physiol Res ; 50(6): 583-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11829319

RESUMO

A common variant of the LHbeta subunit has a varying prevalence in various ethnic groups. The consequences of the presence of mutated luteinizing hormone (LH) concern borderline alterations in pituitary/gonadal function that could be mediated by an altered action of variant LH on gonadal steroidogenesis. A comparison of plasma concentrations of gonadal steroid sex hormones was completed in women heterozygous for variant LH and in women with the wild type of LH in three different age ranges. The sample was a randomly selected group of 177 normal women 16 to 72 years old. Variant LH was determined by immunofluorimetric methods using two combinations of monoclonal antibodies. The ratios of LH measured by the two assays indicated whether the subject was wild type homozygote, heterozygote or homozygote for the variant LHbeta allele. The carriers of the variant LH allele in the group of postmenopausal women showed higher serum testosterone levels than those with the wild type LH. This is in agreement with the clinical observations made previously showing a slightly higher androgenic action in the population with variant LH. No differences were detected in serum LH, FSH, epitestosterone and sex hormone binding globulin (SHBG).


Assuntos
Variação Genética , Hormônios Esteroides Gonadais/sangue , Hormônio Luteinizante/genética , Adolescente , Adulto , Idoso , Epitestosterona/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Heterozigoto , Homozigoto , Humanos , Hormônio Luteinizante/sangue , Pessoa de Meia-Idade , Pós-Menopausa , Pré-Menopausa , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue
15.
Physiol Res ; 49 Suppl 1: S113-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10984080

RESUMO

Epitestosterone competes with testosterone for androgen receptors and inhibits several enzymes of steroidogenesis. Insulin-like growth factors (IGFs) stimulate the growth of prostate cells and directly activate androgen receptors in prostatic tumor cell lines. The prostate-specific antigen (PSA) decreases the affinity of IGF-binding protein-3. The samples were collected from 71 patients suffering from various diseases of the prostate (56 patients without prostate cancer but with benign prostatic hyperplasia and 15 patients with prostate cancer). Correlations between age and IGF-1 (r = -0.281, p<0.05), age and serum epitestosterone (r = -0.261, p<0.05), estradiol and testosterone (r = 0.367, p<0.01), and between estradiol and epitestosterone (r = -0.414, p<0.001) were found. After age adjustment, IGF-I correlated with epitestosterone (r = -0.277, p<0.05). The age correlated positively with PSA (r = 0.286, p<0.05) and negatively with IGF-1 (r = -0.377, p<0.01) in partial correlations. PSA levels were higher in patients with prostate cancer (p<0.00001). Epitestosterone, which is negatively correlating with estradiol and IGF-1, may modulate the development of prostate diseases.


Assuntos
Epitestosterona/sangue , Estradiol/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Antígeno Prostático Específico/sangue , Hiperplasia Prostática/sangue , Neoplasias da Próstata/sangue , Testosterona/sangue , Fatores Etários , Idoso , Humanos , Masculino , Estatística como Assunto
16.
Clin Endocrinol (Oxf) ; 50(5): 661-8, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10468933

RESUMO

OBJECTIVE: The ratio of urinary testosterone (T) to epitestosterone (EpiT) is used to detect T abuse in sport. Also, plasma or urinary concentrations of EpiT have been measured to assess testicular steroidogenesis during hormonal male contraception. Further investigations are required to evaluate the relative contributions of the testis and adrenal to EpiT production. To this purpose, we have compared basal urinary EpiT glucuronide and plasma EpiT and the response to synthetic adrenocorticotrophic hormone (ACTH) stimulation between eugonadal and hypogonadal men. DESIGN AND SUBJECTS: The basal urinary excretion rate of EpiT glucuronide was determined in 34 eugonadal men. Six men, clinically diagnosed as hypogonadal, and 6 out of the 34 eugonadal men previously described, received an intramuscular injection of synthetic ACTH depot (1 mg) at 0800 h on two consecutive days. Blood samples were collected prior to and then at 1.5, 8, 24, 25.5, 32 and 48 h with respect to the first administration (0 h). 24-h urine specimens were collected from 0800 h on days 1 and 2 (baseline) and 3 and 4 (stimulation). MEASUREMENTS: Plasma EpiT, T and cortisol were measured by RIA and urinary EpiT and T, following glucuronide hydrolysis, by gas chromatography-mass spectrometry (extract combines aglycones with a minor amount of urinary free steroids). RESULTS: Basal excretion rates of EpiT glucuronide in eugonadal men (range: 62-751 nmol/24 h) were considerably greater than in hypogonadal men (range: 3-34 nmol/24 h). Mean basal plasma EpiT in eugonadal men (1.32 +/- 0.08 nmol/l) were greater than in hypogonadal men (0.68 +/- 0.04 nmol/l). In each group, synthetic ACTH stimulation increased plasma cortisol 4-fold. In eugonadal men, plasma and urinary EpiT were unchanged whereas plasma and urinary T glucuronide decreased in response to ACTH. In hypogonadal patients, ACTH increased plasma and urinary EpiT while plasma T remained unchanged. CONCLUSION: The testes are the major source of epitestosterone, the adrenal contribution being relatively modest. Following adrenal stimulation, urinary epitestosterone glucuronide increases considerably in hypogonadal men but this increase is masked in eugonadal men because testicular production is probably suppressed by the ACTH-induced rise in cortisol. Activation of the adrenal cortex results in no change or only a small decrease in the urinary T/EpiT ratio in eugonadal men.


Assuntos
Glândulas Suprarrenais/fisiopatologia , Cosintropina , Epitestosterona/urina , Hipogonadismo/fisiopatologia , Detecção do Abuso de Substâncias , Glândulas Suprarrenais/efeitos dos fármacos , Adulto , Estudos de Casos e Controles , Epitestosterona/sangue , Humanos , Hidrocortisona/sangue , Hipogonadismo/sangue , Hipogonadismo/urina , Masculino , Valor Preditivo dos Testes , Testosterona/sangue
18.
Eur J Clin Chem Clin Biochem ; 35(6): 469-73, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9228331

RESUMO

Epitestosterone, a C19-steroid with anti-androgenic activity, was determined in the plasma of 234 boys and men from the ages of 6-86 years, and in the prostate tissue of 15 men 55-82 years of age. It was documented that, while in adulthood the concentration of epitestosterone is about ten times lower than the concentration of testosterone, in the pre-pubertal period the level of epitestosterone is similar or even higher than that of testosterone. In the hyperplastic prostate tissue the content of epitestosterone is comparable to that of androstenedione, it is about twice as high as the content of testosterone and approximately half that of the content of dihydrotestosterone. At least in the case of pre-pubertal boys and in the prostatic tissue it is therefore possible to include epitestosterone into consideration as a regulatory factor for the androgen-dependent events.


Assuntos
Epitestosterona/sangue , Epitestosterona/metabolismo , Próstata/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/sangue , Envelhecimento/metabolismo , Androstenodiona/metabolismo , Criança , Di-Hidrotestosterona/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/sangue , Hiperplasia Prostática/metabolismo , Valores de Referência , Testosterona/metabolismo
19.
J Chromatogr B Biomed Appl ; 687(1): 109-16, 1996 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-9001958

RESUMO

The effect of alcohol (1.2 and 2.0 g/kg) on the urinary testosterone-to-epitestosterone (T/E) ratio was studied by two experiments each conducted with four healthy females and males. The intake of 2.0 g/kg of ethanol within 5 h in the evening significantly increased plasma testosterone concentration and ratio of T/E in urine collected next morning in females. The results suggest that alcohol increases the T/E ratio more in females than in males. The effect of high doses of alcohol on urinary T/E ratio must be kept in mind when doping tests are performed during training periods.


Assuntos
Epitestosterona/urina , Etanol/farmacologia , Testosterona/urina , Glândulas Suprarrenais/efeitos dos fármacos , Adulto , Consumo de Bebidas Alcoólicas , Doping nos Esportes , Epitestosterona/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hormônios Esteroides Gonadais/sangue , Hormônios Esteroides Gonadais/urina , Humanos , Fígado/efeitos dos fármacos , Masculino , Caracteres Sexuais , Detecção do Abuso de Substâncias , Testosterona/sangue
20.
J Clin Endocrinol Metab ; 81(11): 4113-21, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8923869

RESUMO

Hormonally induced azoospermia induced by weekly im injections of testosterone enanthate provides effective and reversible male contraception, but more practical regimens are needed. Given our previous findings that six 200-mg pellets implanted subdermally produced more stable, physiological T levels and reduced the delivered T dose by more than 50% while maintaining equally effective suppression of sperm output with fewer metabolic side-effects than weekly 200-mg testosterone enanthate injections, we sought in this study to determine 1) whether further dose-sparing could be achieved by lower testosterone doses while maintaining efficacy and 2) the efficacy of adding a depot progestin to a suboptimally suppressive depot testosterone dose as a model depot progestin/androgen combination male contraceptive. Healthy volunteers were randomized into groups (n = 10) who received either of two lower T doses (two or four 200-mg T pellets) or four 200-mg T pellets plus a single im injection of 300 mg depot medroxyprogesterone acetate (DMPA). Two T pellets (400 mg, 3 mg/day) had a negligible effect on sperm output. Four T pellets (800 mg, 6 mg/day) suppressed sperm output between the second to fourth postimplant months; output returned to normal by the seventh postimplant month, although only 4 of 10 men became azoospermic or severely oligozoospermic (< 3 mol/L/mL). The addition of a depot progestin markedly increased the extent, but not the rate, of sperm output suppression, with 9 of 10 becoming azoospermic and 10 of 10 becoming severely oligozoospermic. There were no serious adverse effects during the study. Plasma total and free testosterone levels remained within the eugonadal range at all times with each treatment. Plasma epitestosterone was suppressed by all 3 regimens, consistent with a dose-dependent inhibition of endogenous Leydig cell steroidogenesis. Plasma LH and FSH measured by a two-site immunoassay were suppressed in a dose-dependent fashion by T and further suppressed by the addition of DMPA. Sex hormone-binding globulin levels were decreased by DMPA, but not by either T dose. Prostate-specific antigen and lipids (total, low or high density lipoprotein cholesterol, and triglycerides) were not significantly changed in any group. Thus, a depot testosterone preparation with zero order release must be delivered at between 6-9 mg/day to provide optimal (but not uniform) efficacy at inducing azoospermia. The addition of a single depot dose of a progestin to a suboptimal testosterone dose (6 mg/day) markedly enhances the extent, but not the rate, of spermatogenic suppression, with negligible biochemical androgenic side-effects. These findings provide a basis for the use of a progestin/androgen combination depot for hormonal male contraception.


PIP: Clinical research conducted in Australia suggests that a progestin-androgen combination depot has potential for hormonal male contraception. The authors' previous research had indicated that 6 200-mg testosterone enanthate pellets implanted subdermally produced substantial reductions over injections in the delivered testosterone dose while maintaining equally effective suppression of spermatogenesis with few metabolic side effects. The present study sought to determine whether lower testosterone doses would maintain efficiency and to assess the efficacy of adding a depot progestin to a suboptimally suppressive depot testosterone dose (6 mg/day). 10 volunteers received either 2 or 4 200-mg testosterone pellets or 4 200-mg pellets plus a single intramuscular injection of 300-mg depot medroxyprogesterone acetate (DMPA). The testosterone implants alone achieved inadequate suppression of spermatogenesis for a male contraceptive; 400 mg of testosterone (3 mg/day) had a negligible effect on sperm output, while 800 mg (6 mg/day) produced azoospermia or severe oligozoospermia in only 4 of 10 men. However, the addition of DMPA markedly increased the extent, but not the rate, of sperm output suppression: azoospermia was achieved in 9 men and oligozoospermia in all 10 subjects, and sperm suppression persisted for 3 months. Epitestosterone concentrations, used as a marker of Leydig cell steroidogenesis, were decreased in a time- and dose-dependent manner, reaching castrate levels in the combined group. Plasma luteinizing hormone and follicle-stimulating hormone levels were suppressed in a dose-dependent fashion by testosterone and further suppressed by the addition of DMPA. Sex hormone-binding globulin levels were decreased by DMPA, but not by either testosterone dose. Prostate-specific antigens and lipids were not significantly altered by any regimen. There were no discontinuations or reports of side effects.


Assuntos
Congêneres da Progesterona/administração & dosagem , Espermatogênese/efeitos dos fármacos , Testosterona/administração & dosagem , Adulto , Anticoncepção/métodos , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Implantes de Medicamento , Sinergismo Farmacológico , Epitestosterona/sangue , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Acetato de Medroxiprogesterona/administração & dosagem , Pessoa de Meia-Idade , Oligospermia/induzido quimicamente , Bloqueadores de Espermatogênese/administração & dosagem , Testosterona/sangue
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