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1.
Eur J Endocrinol ; 190(1): 54-61, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38141148

RESUMO

OBJECTIVE: Serum testosterone measurements in clinical practice mostly utilize "direct" (non-extraction) immunoassays which have method-specific bias due to steroid cross-reactivity and nonspecific matrix artifacts. Although more accurate, sensitive, and specific liquid chromatography-mass spectrometry (LCMS) dominates in clinical research, the within-person variability of serum testosterone in healthy men using LCMS measurement is not reported. DESIGN: Longitudinal multi-sampling observational study of men in excellent health over 3 months. METHODS: Elite healthy men (n = 325) over 40 years of age in excellent, asymptomatic health provided 9 blood samples over 3 months with serum testosterone, dihydrotestosterone (DHT), estradiol (E2), and estrone (E1) measured by validated LCMS with conventional biochemical and anthropometric variables. RESULTS: Quantitative estimates of within-person variability within day and between day, week, month, and quarter were stable other than an increase due to fasting. The androgen biomarkers most sensitive to age and testosterone among widely used biochemical and anthropometric variables in middle-aged and older men were identified. CONCLUSIONS: This study provides estimates of variability in serum testosterone and the best androgen biomarkers that may prove useful for future studies of androgen action in male ageing.


Assuntos
Androgênios , Testosterona , Pessoa de Meia-Idade , Masculino , Humanos , Idoso , Adulto , Estradiol , Di-Hidrotestosterona , Jejum , Biomarcadores
2.
Math Biosci ; 355: 108940, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36400316

RESUMO

Using a hybrid cellular automaton with stochastic elements, we investigate the effectiveness of multiple drug therapies on prostate cancer (PCa) growth. The ability of Androgen Deprivation Therapy to reduce PCa growth represents a milestone in prostate cancer treatment, nonetheless most patients eventually become refractory and develop castration-resistant prostate cancer. In recent years, a "second generation" drug called enzalutamide has been used to treat advanced PCa, or patients already exposed to chemotherapy that stopped responding to it. However, tumour resistance to enzalutamide is not well understood, and in this context, preclinical models and in silico experiments (numerical simulations) are key to understanding the mechanisms of resistance and to assessing therapeutic settings that may delay or prevent the onset of resistance. In our mathematical system, we incorporate cell phenotype switching to model the development of increased drug resistance, and consider the effect of the micro-environment dynamics on necrosis and apoptosis of the tumour cells. The therapeutic strategies that we explore include using a single drug (enzalutamide), and drug combinations (enzalutamide and everolimus or cabazitaxel) with different treatment schedules. Our results highlight the effectiveness of alternating therapies, especially alternating enzalutamide and cabazitaxel over a year, and a comparison is made with data taken from TRAMP mice to verify our findings.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Camundongos , Animais , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/genética , Receptores Androgênicos/uso terapêutico , Antagonistas de Androgênios/farmacologia , Antagonistas de Androgênios/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Microambiente Tumoral
3.
Math Biosci Eng ; 18(6): 8577-8602, 2021 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-34814314

RESUMO

Prostate cancer is the fifth most common cause of death from cancer, and the second most common diagnosed cancer in men. In the last few years many mathematical models have been proposed to describe the dynamics of prostate cancer under treatment. So far one of the major challenges has been the development of mathematical models that would represent in vivo conditions and therefore be suitable for clinical applications, while being mathematically treatable. In this paper, we take a step in this direction, by proposing a nonlinear distributed-delay dynamical system that explores neuroendocrine transdifferentiation in human prostate cancer in vivo. Sufficient conditions for the existence and the stability of a tumour-present equilibrium are given, and the occurrence of a Hopf bifurcation is proven for a uniform delay distribution. Numerical simulations are provided to explore differences in behaviour for uniform and exponential delay distributions. The results suggest that the choice of the delay distribution is key in defining the dynamics of the system and in determining the conditions for the onset of oscillations following a switch in the stability of the tumour-present equilibrium.


Assuntos
Modelos Biológicos , Modelos Teóricos , Humanos , Fatores de Tempo
4.
J Clin Endocrinol Metab ; 105(6)2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32030409

RESUMO

CONTEXT: Androgen abuse impairs male reproductive and cardiac function, but the rate, extent, and determinants of recovery are not understood. OBJECTIVE: To investigate recovery of male reproductive and cardiac function after ceasing androgen intake in current and past androgen abusers compared with healthy non-users. METHODS: Cross-sectional, observational study recruited via social media 41 current and 31 past users (≥3 months since last use, median 300 days since last use) with 21 healthy, eugonadal non-users. Each provided a history, examination, and serum and semen sample and underwent testicular ultrasound, body composition analysis, and cardiac function evaluation. RESULTS: Current abusers had suppressed reproductive function and impaired cardiac systolic function and lipoprotein parameters compared with non- or past users. Past users did not differ from non-users, suggesting full recovery of suppressed reproductive and cardiac functions after ceasing androgen abuse, other than residual reduced testicular volume. Mean time to recovery was faster for reproductive hormones (anti-Mullerian hormone [AMH], 7.3 months; luteinizing hormone [LH], 10.7 months) than for sperm variables (output, 14.1 months) whereas spermatogenesis (serum follicle-stimulating hormone [FSH], inhibin B, inhibin) took longer. The duration of androgen abuse was the only other variable associated with slower recovery of sperm output (but not hormones). CONCLUSION: Suppressed testicular and cardiac function due to androgen abuse is effectively fully reversible (apart from testis volume and serum sex hormone binding globulin) with recovery taking between 6 to 18 months after ceasing androgen intake with possible cumulative effects on spermatogenesis. Suppressed serum AMH, LH, and FSH represent convenient, useful, and underutilized markers of recovery from androgen abuse.


Assuntos
Androgênios/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Cardiopatias/prevenção & controle , Infertilidade Masculina/prevenção & controle , Recuperação de Função Fisiológica , Reprodução , Espermatogênese , Adolescente , Adulto , Androgênios/administração & dosagem , Estudos de Casos e Controles , Estudos Transversais , Relação Dose-Resposta a Droga , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Seguimentos , Cardiopatias/induzido quimicamente , Cardiopatias/patologia , Humanos , Infertilidade Masculina/induzido quimicamente , Infertilidade Masculina/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
5.
J Gerontol A Biol Sci Med Sci ; 75(9): 1723-1731, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31425577

RESUMO

BACKGROUND: Off-label testosterone prescribing for androgen deficiency (AD)-like sexual and energy symptoms of older men without pathologic hypogonadism has increased dramatically without convincing evidence of efficacy. METHODS: In a randomized, double-blind, placebo-controlled study with three phases, we entered 45 men aged at least 40 years without pathologic hypogonadism but with AD-like energy and/or sexual symptoms to either daily testosterone or placebo gel treatment for 6 weeks in a cross-over study design with a third, mandatory extension phase in which participants chose which previous treatment they preferred to repeat while remaining masked to their original treatment. Primary endpoints were energy and sexual symptoms as assessed by a visual analog scale (Lead Symptom Score [LSS]). RESULTS: Increasing serum testosterone to the healthy young male range produced no significant benefit more than placebo for energy or sexual LSS. Covariate effects of age, body mass index, and pretreatment baseline serum testosterone on quality-of-life scales were detected. Only 1 out of 22 indices from seven quality-of-life scales was significantly improved by testosterone treatment over placebo. Participants did not choose testosterone significantly more than placebo as their preferred treatment in the third phase. CONCLUSIONS: Six-week testosterone treatment does not improve energy or sexual symptoms more than placebo in symptomatic men without pathologic hypogonadism.


Assuntos
Androgênios/deficiência , Testosterona/uso terapêutico , Fatores Etários , Índice de Massa Corporal , Estudos Cross-Over , Método Duplo-Cego , Fadiga/tratamento farmacológico , Fadiga/etiologia , Humanos , Masculino , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Disfunções Sexuais Fisiológicas/etiologia
6.
J Endocr Soc ; 3(8): 1531-1540, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31384715

RESUMO

CONTEXT: Can injectable testosterone undecanoate (TU) be administered effectively and acceptably by the subcutaneous (SC) route? OBJECTIVE: To investigate the acceptability and pharmacokinetics (PK) of SC injection of TU. DESIGN: Randomized sequence, crossover clinical study of SC vs IM TU injections. SETTING: Ambulatory clinic of an academic andrology center. PARTICIPANTS: Twenty men (11 hypogonadal, 9 transgender men) who were long-term users of TU. injections. Intervention: Injection of 1000 mg TU (in 4 mL castor oil vehicle) by SC or IM route. Main Outcome Measures: Patient-reported pain, acceptability, and preference scales. PK by measurement of serum testosterone, dihydrotestosterone (DHT), and estradiol (E2) concentrations with application of population PK methods and dried blood spot (DBS) sampling. RESULTS: Pain was greater after SC compared with IM injection 24 hours (but not immediately) after injection but both routes were equally acceptable. Ultimately 11 preferred IM, 6 preferred SC, and 3 had no preference. The DBS-based PK analysis of serum testosterone revealed a later time of peak testosterone concentration after SC vs IM injection (8.0 vs 3.3 days) but no significant route differences in model-predicted peak testosterone concentration (8.4 vs 9.6 ng/mL) or mean resident time (183 vs 110 days). The PK of venous serum testosterone, DHT, and E2 did not differ according to route of injection. CONCLUSIONS: We conclude that SC TU injection is acceptable but produces greater pain 24 hours after injection that may contribute to the overall majority preference for the IM injection. The PK of testosterone, DHT, or E2 did not differ substantially between SC and IM routes. Hence whereas further studies are required, the SC route represents an alternative to IM injections without a need to change dose for men for whom IM injection is not desired or recommended.

7.
Hum Reprod ; 34(5): 795-803, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30951144

RESUMO

STUDY QUESTION: What is the natural history of outcomes of sperm cryostorage at an Australian tertiary academic centre? SUMMARY ANSWER: Cryostorage is feasible in virtually all men facing gonadotoxic therapy but the timing of sperm disposal varies according to the reason for it. WHAT IS KNOWN ALREADY: Gonadotoxic treatment for cancer or non-cancer diseases damages spermatogenesis and impairs male fertility. Sperm cryopreservation is an established technique to preserve male fertility prior to gonadotoxic treatment. STUDY DESIGN, SIZE, DURATION: A retrospective review of clinical, anthropometric, semen analysis and hormonal data from 1978 to 2017 involving 2717 men comprising 2085 men with cancer, 234 non-cancer disease and 398 healthy controls, in a single tertiary academic centre with the same clinic and laboratory staff. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Sperm output was analysed according to diseases, the feasibility of sperm cryostorage notably for adolescents, regional access to an urban cryostorage facility, the determinants of sperm output and time-dependent disposal of cryostored sperm. Semen samples were assessed by contemporaneous WHO methods. MAIN RESULTS AND THE ROLE OF CHANCE: Of 2085 men with cancer, 904 (43%) had haematological malignancies, 680 (33%) testicular cancers and 136 (6.5%) were adolescents. Most men (89%) and adolescents (80%) could collect sperm. Sperm output for all cancers and non-cancer diseases was lower than controls. Sperm output correlated positively with total testicular volume (r = 0.44, P < 0.0001) and negatively with serum FSH and LH (r = -0.24, -0.12, respectively, both P < 0.0001) but not testosterone. For all stored samples, the median time in cryostorage was 8.5 years, 7% were transferred for use to induce pregnancy (median time 2.5 years) and 62.2% were discarded as no longer needed (return of fertility, 35.9% median 3.5 years; death, 26.3%, median 6.5 years), the high disposal rate reflecting regular annual follow-up to establish ongoing need for continued cryostorage. Cryostorage facilities are not available in remote and rural areas of the State and the proportion of outer regional and remote area residents cryostoring sperm was only about half that compared with urban residents. LIMITATIONS, REASONS FOR CAUTION: This study does not report the pregnancy outcomes of the patients who used the cryostored sperm, due to recent limitations on health data privacy. WIDER IMPLICATIONS OF THE FINDINGS: Sperm cryostorage is feasible for virtually all men, including sufficiently mature adolescents, who can collect semen to insure future paternity as well as making positive psychological preparation for the patient's survival. Disposal of cryostored material when no longer required is efficient with regular follow-up. Sperm cryopreservation should be an integral part of comprehensive treatment plan in men receiving gonadotoxic treatment but remains underutilized. STUDY FUNDING/COMPETING INTEREST(S): There was no external funding for this study and there were no relevant conflicts of interest.


Assuntos
Antineoplásicos/efeitos adversos , Criopreservação , Preservação da Fertilidade/métodos , Recuperação Espermática , Espermatozoides/efeitos dos fármacos , Adolescente , Adulto , Estudos de Viabilidade , Humanos , Masculino , Neoplasias/tratamento farmacológico , New South Wales , Estudos Retrospectivos , Análise do Sêmen , Espermatogênese/efeitos dos fármacos , Adulto Jovem
8.
J Clin Endocrinol Metab ; 103(6): 2277-2283, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29584875

RESUMO

Background: The impact of testosterone (T) treatment on antidoping detection tests in female-to-male (F2M) transgender men is unknown. We investigated urine and serum sex steroid and luteinizing hormone (LH) profiles in T-treated F2M men to determine whether and, if so, how they differed from hypogonadal and healthy control men. Method: Healthy transgender (n = 23) and hypogonadal (n = 24) men aged 18 to 50 years treated with 1000 mg injectable T undecanoate provided trough urine and blood samples and an additional earlier postinjection sample (n = 21). Healthy control men (n = 20) provided a single blood and urine sample. Steroids were measured by mass spectrometry-based methods in urine and serum, LH by immunoassay, and uridine 5'-diphospho-glucuronosyltransferase 2B17 genotype by polymerase chain reaction. Results: Urine LH, human chorionic gonadotropin, T, epitestosterone (EpiT), androsterone (A), etiocholanolone (Etio), A/Etio ratio, dehydroepiandrosterone (DHEA), dihydrotestosterone (DHT), and 5α,3α- and 5ß,3α-androstanediols did not differ between groups or by time since last T injection. Urine T/EpiT ratio was <4 in all controls and 12/68 (18%) samples from T-treated men, but there was no difference between T-treated groups. Serum estradiol, estrone, and DHEA were higher in transgender men, and serum T and DHT were higher in earlier compared with trough blood samples, but serum LH, follicle-stimulating hormone, and 3α- and 3ß,5α-diols did not differ between groups. Conclusion: Urine antidoping detection tests in T-treated transgender men can be interpreted like those of T-treated hypogonadal men and are unaffected by time since last T dose. Serum steroids are more sensitive to detect exogenous T administration early but not later after the last T dose.


Assuntos
Androgênios/metabolismo , Estrogênios/metabolismo , Hipogonadismo/tratamento farmacológico , Testosterona/análogos & derivados , Transexualidade/tratamento farmacológico , Adolescente , Adulto , Androgênios/sangue , Androgênios/urina , Androsterona/sangue , Androsterona/urina , Desidroepiandrosterona/sangue , Desidroepiandrosterona/urina , Di-Hidrotestosterona/sangue , Di-Hidrotestosterona/urina , Estradiol/sangue , Estradiol/urina , Estrogênios/sangue , Estrogênios/urina , Estrona/sangue , Estrona/urina , Humanos , Hipogonadismo/sangue , Hipogonadismo/urina , Hormônio Luteinizante/sangue , Hormônio Luteinizante/urina , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Testosterona/sangue , Testosterona/uso terapêutico , Testosterona/urina , Pessoas Transgênero , Transexualidade/sangue , Transexualidade/urina , Adulto Jovem
9.
J Clin Endocrinol Metab ; 99(7): 2592-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24684468

RESUMO

CONTEXT: Testosterone (T) and nandrolone (N) esters require deep im injections by medical personnel but these often deposit injectate into sc fat so that more convenient sc self-administration may be feasible. OBJECTIVE: To investigate the feasibility and pharmacology of sc injection of N decanoate in healthy men using dried blood spot (DBS) for frequent blood sampling without clinic visits. SETTING AND DESIGN: Healthy male volunteers received 100 mg N decanoate by a single sc injection. Finger-prick capillary blood was spotted onto filter paper before injection daily at home for 21 d and stored at room temperature. Venous whole blood was also spotted onto filter paper before and weekly for 3 wk after injection. DBS were extracted for assay of N and T by liquid chromatography tandem mass spectrometry in a single batch with serum concentrations estimated with adjustment for capillary blood sample volume and hematocrit to define peak (N) or nadir (T) time and concentration from individual daily measurements. RESULTS: Daily serum N peaked 2.50 ± 0.25 (SEM) ng/mL at a median (range) of 6 (4-13) days causing a reduction in serum T from 3.50 ± 0.57 ng/mL at baseline to a nadir of 0.38 ± 0.13 (SEM) ng/mL (89 ± 3% suppression) at a median (range) of 8 (5-16) days. Simultaneously sampled capillary, venous whole blood, and serum gave almost identical results for serum T and N. Finger-pricks and sc injections were well tolerated. CONCLUSIONS: This study demonstrates that A) DBS sampling with liquid chromatography mass spectrometry steroid analysis achieves frequent time sampling in the community without requiring clinic visits, venesection, or frozen serum storage, and B) androgen esters in an oil vehicle can be delivered effectively by sc injection, thus avoiding the need for medically supervised deep-im injections.


Assuntos
Preparações de Ação Retardada/farmacocinética , Teste em Amostras de Sangue Seco/métodos , Nandrolona/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Adulto , Coleta de Amostras Sanguíneas/métodos , Cromatografia Líquida/métodos , Preparações de Ação Retardada/administração & dosagem , Hormônio Foliculoestimulante/sangue , Humanos , Injeções Subcutâneas , Hormônio Luteinizante/sangue , Masculino , Nandrolona/administração & dosagem , Nandrolona/sangue , Nandrolona/farmacocinética , Decanoato de Nandrolona , Testosterona/sangue , Adulto Jovem
10.
J Steroid Biochem Mol Biol ; 141: 113-20, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24495617

RESUMO

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


Assuntos
Leuprolida/administração & dosagem , Hormônio Luteinizante/sangue , Substâncias para Melhoria do Desempenho/administração & dosagem , Testosterona/sangue , Adulto , Di-Hidrotestosterona/sangue , Di-Hidrotestosterona/urina , Dopagem Esportivo , Estradiol/sangue , Estradiol/urina , Humanos , Leuprolida/farmacocinética , Leuprolida/urina , Hormônio Luteinizante/urina , Masculino , Pessoa de Meia-Idade , Nandrolona/análogos & derivados , Nandrolona/farmacologia , Decanoato de Nandrolona , Substâncias para Melhoria do Desempenho/farmacocinética , Substâncias para Melhoria do Desempenho/urina , Testosterona/urina , Adulto Jovem
11.
Clin Endocrinol (Oxf) ; 77(5): 755-63, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22563890

RESUMO

OBJECTIVE: To determine serum concentrations, intra-individual variability and impact of age-related co-morbidities on serum testosterone (T), dihydrotestosterone (DHT), estradiol (E(2)) and estrone (E(1)) in older men. DESIGN: Observational, repeated measures study. PARTICIPANTS: Men (n = 325) with 40 years and older self-reporting very good or excellent health. MEASUREMENTS: Standardized history, physical examination and collection of nine blood samples at fixed time intervals were measured over 3 months (three at 20 min intervals on days 1 (fasting) and 2 (non-fasting), one at days 7, 30 and 90). Serum T, DHT, E(2) and E(1) (n = 2900, > 99% of scheduled samples) measured by liquid chromatography-tandem mass spectrometry (LC-MS) were analysed by linear mixed model analysis with fasting, age and obesity as covariables. RESULTS: Mean serum T did not vary with age (P = 0·76) but obesity (-0·35 nM per body mass index (BMI) unit, P < 0·0001) and ex-smoker status (-1·6 nM, P < 0·001) had significant effects. Serum DHT was increased with age (+0·011 nM per year, P = 0·001) but decreased with obesity (-0·05 nM per BMI unit, P < 0·0001). Serum E(2) did not vary with age (P = 0·31) or obesity (P = 0·12). Overnight fasting increased (by 9-16%, all P < 0·001) and reduced variability in morning serum T, DHT, E(2) and E(1). Non-fasting serum T and DHT were stable over time (day, week, month or 3 months; P > 0·28). CONCLUSIONS: Serum T, DHT and E(2) displayed no decrease associated with age among men over 40 years of age who self-report very good or excellent health although obesity and ex-smoking status were associated with decreased serum androgens (T and DHT) but not E(2). These findings support the interpretation that the age-related decline in blood T accompanying non-specific symptoms in older men may be due to accumulating age-related co-morbidities rather than a symptomatic androgen deficiency state.


Assuntos
Di-Hidrotestosterona/sangue , Estradiol/sangue , Testosterona/sangue , Idoso , Humanos , Masculino , Pessoa de Meia-Idade
13.
Ann Intern Med ; 153(10): 621-32, 2010 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-21079217

RESUMO

BACKGROUND: Benign prostatic hypertrophy increases with age and can result in substantially decreased quality of life for older men. Surgery is often required to control symptoms. It has been hypothesized that long-term administration of a nonamplifiable pure androgen might decrease prostate growth, thereby decreasing or delaying the need for surgical intervention. OBJECTIVE: To test the hypothesis that dihydrotestosterone (DHT), a nonamplifiable and nonaromatizable pure androgen, reduces late-life prostate growth in middle-aged men. DESIGN: Randomized, placebo-controlled, parallel-group trial. (Australian New Zealand Clinical Trials Registry number: ACTRN12605000358640) SETTING: Ambulatory care research center. PARTICIPANTS: Healthy men (n = 114) older than 50 years without known prostate disease. INTERVENTION: Transdermal DHT (70 mg) or placebo gel daily for 2 years. MEASUREMENTS: Prostate volume was measured by ultrasonography; bone mineral density (BMD) and body composition were measured by dual-energy x-ray absorptiometry; and blood samples and questionnaires were collected every 6 months, with data analyzed by mixed-model analysis for repeated measures. RESULTS: Over 24 months, there was an increase in total (29% [95% CI, 23% to 34%]) and central (75% [CI, 64% to 86%]; P < 0.01) prostate volume and serum prostate-specific antigen level (15% [CI, 6% to 24%]) with time on study, but DHT had no effect (P > 0.2). Dihydrotestosterone treatment decreased spinal BMD (1.4% [CI, 0.6% to 2.3%]; P < 0.001) at 24 months but not hip BMD (P > 0.2) and increased serum aminoterminal propeptide of type I procollagen in the second year of the study compared with placebo. Dihydrotestosterone increased serum DHT levels and its metabolites (5α-androstane-3α,17ß-diol and 5α-androstane-3ß,17ß-diol) and suppressed serum testosterone, estradiol, luteinizing hormone, and follicle-stimulating hormone levels. Dihydrotestosterone increased hemoglobin levels (7% [CI, 5% to 9%]), serum creatinine levels (9% [CI, 5% to 11%]), and lean mass (2.4% [CI, 1.6% to 3.1%) but decreased fat mass (5.2% [CI, 2.6% to 7.7%]) (P <0.001 for all). Protocol-specific discontinuations due to DHT were asymptomatic increased hematocrit (n = 8), which resolved after stopping treatment, and increased prostate-specific antigen levels (n = 3; none with prostate cancer) in the DHT group. No serious adverse effects due to DHT occurred. LIMITATION: Negative findings on prostate growth cannot exclude adverse effects on the natural history of prostate cancer. CONCLUSION: Dihydrotestosterone treatment for 24 months has no beneficial or adverse effect on prostate growth but causes a decrease in spinal but not hip BMD. These findings have important implications for the wider use of nonsteroidal pure androgens in older men. PRIMARY FUNDING SOURCE: BHR Pharma.


Assuntos
Androgênios/administração & dosagem , Di-Hidrotestosterona/administração & dosagem , Próstata/efeitos dos fármacos , Próstata/crescimento & desenvolvimento , Administração Cutânea , Antígenos de Neoplasias/sangue , Composição Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Colágeno Tipo I/sangue , Di-Hidrotestosterona/sangue , Método Duplo-Cego , Estradiol/sangue , Proteínas Fetais , Géis , Humanos , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos , Pró-Colágeno , Próstata/diagnóstico por imagem , Antígeno Prostático Específico/sangue , Hiperplasia Prostática/prevenção & controle , Testosterona/sangue , Ultrassonografia
14.
Asian J Androl ; 12(2): 227-33, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20118950

RESUMO

Pain following depot intramuscular (IM) injection of oil vehicle-based drugs has been little studied. This study aimed to determine prospectively the prevalence, determinants, severity and functional consequences of pain during the week after IM injection of 1 000 mg testosterone undecanoate (TU) in a 4-mL castor oil vehicle. Androgen-deficient men receiving regular T replacement therapy at an academic andrology clinic were recruited to report pain scores using a coloured visual linear analogue scale at seven times over the first day and daily for a week after a deep IM gluteal injection. The time course and covariables influencing pain scores were analysed by mixed model analysis of variance (ANOVA). Following 168 injections in 125 men, pain was reported by 80% of men, peaking immediately after injection, reaching only moderate severity, lasting 1-2 days and returning to baseline by day 4. The pain required little analgesic use and produced minimal interference in daily activities. The time course of pain scores was reproducible in the 43 men who underwent two consecutive injections. Pain was more severe in men who had an earlier painful injection, but less severe in older and more obese men. There were negligible differences in post-injection pain experience between experienced nurses administering injections. Deep IM gluteal injection of depot TU in 4-mL castor oil is well tolerated and post-injection pain is influenced by earlier painful injection experience, as well as age and obesity.


Assuntos
Dor/etiologia , Testosterona/análogos & derivados , Análise de Variância , Preparações de Ação Retardada , Humanos , Masculino , Pessoa de Meia-Idade , Testosterona/administração & dosagem , Testosterona/efeitos adversos
15.
Clin Endocrinol (Oxf) ; 73(1): 102-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19891698

RESUMO

BACKGROUND: Life-long testosterone replacement therapy (TRT) for younger men with organic androgen deficiency is best provided by depot testosterone (T) products. This study compared directly the two long-acting depot T products, subdermal T implants (TI) and injectable T undecanoate (TU) for maintenance of TRT. DESIGN, SETTING AND PARTICIPANTS: Men with organic androgen deficiency (n = 38) undergoing regular TRT at an academic Andrology centre were recruited for a two period, randomized sequence, cross-over clinical trial without intervening wash-out period of TRT maintenance. OUTCOMES: For both depot T products, their pharmacokinetics and pharmacodynamics were evaluated using a range of androgen sensitive clinical, laboratory and quality of life measures as well as preference for ongoing treatment after experience of both products. RESULTS: The two depot T products had distinct pharmacokinetics and were not bioequivalent. However, there were no consistent clinical differences in a comprehensive range of pharmacodynamic measures reflecting androgen effects on biochemistry and haematology, muscle mass and strength, and quality of life, mood and sexual function. The majority (91%) of participants chose TU over TI at study completion. CONCLUSION: Despite significant pharmacokinetic differences, the two depot T products are clinically interchangeable allowing for choice dependent on patient and physician delivery preference in practice but most patients preferred the injectable over the implantable form.


Assuntos
Terapia de Reposição Hormonal/métodos , Hipogonadismo/tratamento farmacológico , Testosterona/administração & dosagem , Androgênios/deficiência , Estudos Cross-Over , Implantes de Medicamento , Humanos , Masculino , Satisfação do Paciente , Qualidade de Vida , Testosterona/análogos & derivados , Testosterona/farmacocinética , Testosterona/uso terapêutico
16.
J Clin Endocrinol Metab ; 88(10): 4659-67, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14557437

RESUMO

WHO studies provided proof of concept for hormonal male contraception using a prototype androgen-alone regimen. Combined testosterone plus progestin regimens offer more practical promise, but no contraceptive efficacy studies have been completed. The objective of this study was to establish the proof of principle for depot hormonal androgen/progestin combination as a male contraceptive. We performed a contraceptive efficacy study of 55 healthy men in stable fertile relationships seeking a change in contraceptive method. Testosterone (four 200-mg implants, every 4 or 6 months) and 300 mg depot medroxyprogesterone acetate, im, every 3 months were administered. Once sperm output was suppressed (<1 million/ml for 2 consecutive months), men entered a 12-month contraceptive efficacy period, ceasing other contraception. The main outcome measure was contraceptive failure (pregnancy) rate. No pregnancies occurred in 426 person-months (35.5 person-years; 95% confidence limits for contraceptive failure rate, 0-8%/annum), superior to the first year failure rate of condoms, the only reversible male method. Sperm density fell rapidly, so 94% of men entered the efficacy phase by 3 months, with only 2 of 55 (3.6%) men not sufficiently suppressed to enter efficacy. A few men treated with testosterone implants at 6-month intervals demonstrated androgen deficiency symptoms and/or escape of gonadotropin and spermatogenic suppression between months 5 and 6; after a protocol amendment, all men receiving testosterone implants at 4-month intervals avoided androgen deficiency or loss of gonadotropin and sperm output suppression. Recovery was complete (median, 3.6 months to sperm reappearance and 5.0 months to 20 million sperm/ml) in all but one man with an incidental testicular disorder. Discontinuations were for protocol-related reasons (n = 15) or altered personal circumstances (n = 12), but there were no serious adverse effects related to drug exposure. The first male contraceptive efficacy study using a prototype depot androgen/progestin combination demonstrates high contraceptive efficacy with satisfactory short-term safety and recovery of spermatogenesis. Further studies of purpose-developed products are required to extend the overall safety and efficacy experience with depot androgen/progestin combinations, the most promising approach to hormonal male contraception.


Assuntos
Anticoncepcionais Masculinos/administração & dosagem , Hormônios Esteroides Gonadais/administração & dosagem , Acetato de Medroxiprogesterona/administração & dosagem , Testosterona/administração & dosagem , Adolescente , Adulto , Anticoncepção/métodos , Preparações de Ação Retardada , Combinação de Medicamentos , Implantes de Medicamento , Hormônio Foliculoestimulante/sangue , Hormônios Esteroides Gonadais/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Contagem de Espermatozoides , Testosterona/sangue
17.
J Androl ; 24(4): 604-11, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12826700

RESUMO

A multicenter, open-label, randomized efficacy and safety study was performed with combined human chorionic gonadotropin (hCG) and recombinant follicle-stimulating hormone (recFSH) (Puregon(R)) treatment to induce spermatogenesis in hypogonadotropic hypogonadal male patients. Patients were pretreated for 16 weeks with hCG to normalize testosterone levels. A total of 30 of 49 (61%) subjects had normalized testosterone levels but were still azoospermic after the hCG-alone phase. These patients were randomized into 2 treatment schemes with recFSH (2 x 225 IU recFSH per week [group A] or 3 x 150 IU recFSH per week [group B]), in combination with hCG for a period of 48 weeks. Total testosterone increased during the hCG-alone period from 1.08 and 1.22 ng/mL to 6.26 and 4.52 ng/mL for groups A and B, respectively. Combined gonadotropin treatment was effective in inducing spermatogenesis (sperm count >/=1 x 10(6)/mL) in 14 of 30 subjects (47%) and this was achieved after a median duration of treatment of approximately 5.5 months. Treatment time necessary for first sperm cells to appear in the ejaculate was related to the initial testicular volume. Subjects with a history of maldescended testes (11 of 30 subjects, 37%) showed a lower mean response to treatment as indicated by the relatively lower number of subjects reaching levels of at least 1 x 10(6) sperm cells per milliliter. Combined testicular volume increased during combined gonadotropin treatment from 11.4 to 24.0 mL. Although subjects with a history of maldescended testes had a lower starting testicular volume, subjects with and without a history of maldescended testes showed approximately the same relative increase in testicular volume. Total testosterone levels showed only a minor further increase during the combined gonadotropin treatment period. In conclusion, a weekly dose of 450 IU (3 x 150 IU or 2 x 225 IU) recFSH, in addition to hCG, was able to induce spermatogenesis in many hypogonadotropic azoospermic men who failed to respond to treatment with hCG alone.


Assuntos
Gonadotropina Coriônica/administração & dosagem , Hormônio Foliculoestimulante Humano/administração & dosagem , Hipogonadismo/tratamento farmacológico , Oligospermia/tratamento farmacológico , Espermatogênese/efeitos dos fármacos , Adulto , Gonadotropina Coriônica/efeitos adversos , Quimioterapia Combinada , Hormônio Foliculoestimulante Humano/efeitos adversos , Humanos , Masculino , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Testículo/anatomia & histologia , Testículo/efeitos dos fármacos , Testosterona/sangue , Resultado do Tratamento
18.
Hum Reprod ; 17(3): 625-33, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11870114

RESUMO

BACKGROUND: Predictors of fertility or spermatogenesis during gonadotrophin therapy of gonadotrophin-deficient men remain poorly defined. METHODS AND RESULTS: In order to evaluate potential predictors, this study evaluated 29 consecutive gonadotrophin-deficient men all desiring paternity who received 43 courses of therapy in one centre between 1982 and 1998. The Kaplan-Meier survival analysis estimates of median (SE) time to a sperm concentration of >0, >5 and >20 x 10(6)/ml were 5.5 (1.1), 12.4 (2.3) and 29.1 (1.9) months respectively. Conception occurred in 22/43 cycles (with eight men achieving two pregnancies) with a median (SE) Kaplan-Meier estimate of 20.5 (4.7) months. The median sperm concentration at conception was 5.0 (SE 2.0; range 0.0-59.5) x 10(6)/ml. Multivariate correlated Cox proportional hazards models predicting these same sperm thresholds and conception were developed by forward stepwise variable selection with verification of the model by backward stepping. Larger testicular volume, prior gonadotrophin therapy, completion of puberty, older age, the absence of adverse fertility factors and the absence of multiple pituitary hormone deficiency predicted a favourable response. Multivariate modelling suggests that the two most important predictors of sperm output are testicular volume and pubertal status. The most important potentially modifiable predictor was prior gonadotrophin therapy. The efficacy of recombinant and urinary FSH were similar. Prior androgen therapy and partner's age did not appear to be significant. CONCLUSIONS: Since prolonged treatment may be required to induce spermatogenesis, attention to these predictors may allow appropriate early use of advanced reproductive technologies.


Assuntos
Hormônio Foliculoestimulante/uso terapêutico , Gonadotropinas/deficiência , Infertilidade Masculina/tratamento farmacológico , Infertilidade Masculina/fisiopatologia , Erros Inatos do Metabolismo/tratamento farmacológico , Gravidez , Espermatogênese , Adulto , Feminino , Fertilidade , Fertilização , Hormônio Foliculoestimulante/urina , Previsões , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Proteínas Recombinantes/uso terapêutico , Contagem de Espermatozoides , Análise de Sobrevida , Fatores de Tempo
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