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1.
Cell ; 150(4): 667-8, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-22901799

RESUMO

There has not been a new reversible contraceptive for men since the development of the condom, centuries ago. Matzuk et al. describe a new molecular approach using administration of a small molecule to directly and reversibly inhibit spermatogenesis in mice by blocking the function of a testicular bromodomain without apparent adverse effect on the organism or offspring.

2.
Contraception ; 124: 110064, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37210024

RESUMO

Injectable male hormonal contraceptives are effective for preventing pregnancy in clinical trials; however, users may prefer to avoid medical appointments and injections. A self-administered transdermal contraceptive gel may be more acceptable for long-term contraception. Transdermal testosterone gels are widely used to treat hypogonadism and transdermal administration may have utility for male contraception; however, no efficacy data from transdermal male hormonal contraceptive gel are available. We designed and are currently conducting an international, multicenter, open-label study of self-administration of a daily combined testosterone and segesterone acetate (Nestorone) gel for male contraception. The transdermal approach to male contraception raises novel considerations regarding adherence with the daily gel, as well as concern about the potential transfer of the gel and the contraceptive hormones to the female partner. Enrolled couples are in committed relationships. Male partners have baseline normal spermatogenesis and are in good health; female partners are regularly menstruating and at risk for unintended pregnancy. The study's primary outcome is the rate of pregnancy in couples during the study's 52-week efficacy phase. Secondary endpoints include the proportion of male participants suppressing sperm production and entering the efficacy phase, side effects, hormone concentrations in male participants and their female partners, sexual function, and regimen acceptability. Enrollment concluded on November 1, 2022, with 462 couples and enrollment is now closed. This report outlines the strategy and design of the first study to examine the contraceptive efficacy of a self-administered male hormonal contraceptive gel. The results will be presented in future reports. IMPLICATIONS: The development of a safe, effective, reversible male contraceptive would improve contraceptive options and may decrease rates of unintended pregnancy. This manuscript outlines the study design and analysis plan for an ongoing large international trial of a novel transdermal hormone gel for male contraception. Successful completion of this and future studies of this formulation may lead to the approval of a male contraceptive.


Assuntos
Anticoncepcionais Masculinos , Testosterona , Gravidez , Masculino , Humanos , Feminino , Sêmen , Anticoncepção/métodos , Anticoncepcionais , Géis
3.
Andrology ; 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37727884

RESUMO

BACKGROUNDS: Despite a wide spectrum of contraceptive methods for women, the unintended pregnancy rate remains high (45% in the US), with 50% resulting in abortion. Currently, 20% of global contraceptive use is male-directed, with a wide variation among countries due to limited availability and lack of efficacy. Worldwide studies indicate that >50% of men would opt to use a reversible method, and 90% of women would rely on their partner to use a contraceptive. Additional reasons for novel male contraceptive methods to be available include the increased life expectancy, sharing the reproductive risks among partners, social issues, the lack of pharma industry involvement and the lack of opinion makers advocating for male contraception. AIM: The present guidelines aim to review the status regarding male contraception, the current state of the art to support the clinical practice, recommend minimal requirements for new male contraceptive development and provide and grade updated, evidence-based recommendations from the European Society of Andrology (EAA) and the American Society of Andrology (ASA). METHODS: An expert panel of academicians appointed by the EAA and the ASA generated a consensus guideline according to the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) system. RESULTS: Sixty evidence-based and graded recommendations were produced on couple-centered communication, behaviors, barrier methods, semen analysis and contraceptive efficacy, physical agents, surgical methods, actions before initiating male contraception, hormonal methods, non-hormonal methods, vaccines, and social and ethical considerations. CONCLUSION: As gender roles transform and gender equity is established in relationships, the male contribution to family planning must be facilitated. Efficient and safe male-directed methods must be evaluated and introduced into clinical practice, preferably reversible, either hormonal or non-hormonal. From a future perspective, identifying new hormonal combinations, suitable testicular targets, and emerging vas occlusion methods will produce novel molecules and products for male contraception.

4.
Endocr Rev ; 29(4): 465-93, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18436704

RESUMO

Despite significant advances in contraceptive options for women over the last 50 yr, world population continues to grow rapidly. Scientists and activists alike point to the devastating environmental impacts that population pressures have caused, including global warming from the developed world and hunger and disease in less developed areas. Moreover, almost half of all pregnancies are still unwanted or unplanned. Clearly, there is a need for expanded, reversible, contraceptive options. Multicultural surveys demonstrate the willingness of men to participate in contraception and their female partners to trust them to do so. Notwithstanding their paucity of options, male methods including vasectomy and condoms account for almost one third of contraceptive use in the United States and other countries. Recent international clinical research efforts have demonstrated high efficacy rates (90-95%) for hormonally based male contraceptives. Current barriers to expanded use include limited delivery methods and perceived regulatory obstacles, which stymie introduction to the marketplace. However, advances in oral and injectable androgen delivery are cause for optimism that these hurdles may be overcome. Nonhormonal methods, such as compounds that target sperm motility, are attractive in their theoretical promise of specificity for the reproductive tract. Gene and protein array technologies continue to identify potential targets for this approach. Such nonhormonal agents will likely reach clinical trials in the near future. Great strides have been made in understanding male reproductive physiology; the combined efforts of scientists, clinicians, industry and governmental funding agencies could make an effective, reversible, male contraceptive an option for family planning over the next decade.


Assuntos
Anticoncepção/tendências , Anticoncepção/métodos , Anticoncepção/psicologia , Anticoncepcionais Masculinos/uso terapêutico , Anticoncepcionais Orais Hormonais/uso terapêutico , Humanos , Masculino , Modelos Biológicos , Aceitação pelo Paciente de Cuidados de Saúde , Espermatogênese/efeitos dos fármacos , Espermatogênese/fisiologia , Testículo/efeitos dos fármacos , Testículo/fisiologia
5.
Contraception ; 102(1): 52-57, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32298717

RESUMO

OBJECTIVE: To determine men's satisfaction with and acceptability of a once-daily, oral regimen of dimethandrolone undecanoate (DMAU) versus placebo when used for 28 days. STUDY DESIGN: After a Phase I double-blind, randomized, placebo-controlled, dose-escalating trial of oral DMAU for 28-days, 57 healthy male volunteers completed a survey assessing their experience and satisfaction with the regimen. In the trial, participants were randomized to receive up to 4 DMAU capsules daily versus placebo and instructed to ingest them within 30 min of consuming a high fat meal. Pharmacokinetic and pharmacodynamic profiles were performed, followed by a 6-week recovery phase. Participants were counseled that they could not rely on the drug for contraception. RESULTS: Fifty-seven participants were offered acceptability surveys (39 DMAU, 18 placebo). Most respondents, 80% (45/56), reported satisfaction with the method; 77% (44/57) would recommend it. 54% (31/57), reported that, if available, they would use the method as their primary contraceptive. More respondents reported satisfaction with active DMAU than placebo (87% vs. 67%; p = 0.05). Most respondents, 91% (52/57), reported no difficulty with having to take up to 4 pills within 30 min of ingesting a high-fat meal. CONCLUSION: Most participants reported that the study method, daily oral DMAU or placebo, was satisfactory and acceptable. Having to take the drug after a high-fat meal did not detract from acceptability. IMPLICATIONS: Most participants in a 4-week trial of daily DMAU capsules would recommend and use the method. High satisfaction among DMAU and placebo groups affirms acceptability of a daily male contraceptive pill, warranting further study of oral DMAU.


Assuntos
Anticoncepcionais Masculinos , Anticoncepção , Método Duplo-Cego , Humanos , Masculino , Nandrolona/análogos & derivados
6.
J Clin Endocrinol Metab ; 105(3)2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31976519

RESUMO

BACKGROUND: 11ß-methyl-19-nortestosterone (11ß-MNT) is a modified testosterone (T) with androgenic and progestational activity. A single oral dose of the prodrug, 11ß-MNT dodecylcarbonate (11ß-MNTDC), was well tolerated in healthy men. METHODS: We conducted a randomized, double-blind study at 2 academic medical centers. 42 healthy men (18-50 years) were randomized to receive oral placebo or 11ß-MNTDC, 200 or 400 mg daily, for 28 consecutive days. Primary outcome (safety and tolerability) measures were assessed twice per week. Subjects underwent serial blood sampling over 24 hours on days 1 and 28 to assess secondary outcomes: pharmacokinetics (serum drug concentrations); pharmacodynamics of 11ß-MNTDC (serum sex steroids and gonadotropins); and mood and sexual function (via validated questionnaires). RESULTS: There were no serious adverse events. No participants discontinued because of an adverse event or laboratory test abnormality. 11ß-MNTDC resulted in a dose-related increase in serum 11ß-MNTDC and 11ß-MNT concentrations sustained over 24 hours. Administration of 11ß-MNTDC resulted in a marked suppression of serum gonadotropins, T, calculated free T, estradiol, and SHBG over the treatment period (P < 0.01). Adverse effects that may be related to 11ß-MNTDC included weight gain, acne, headaches, fatigue, and mild mood changes, with 5 men reporting decreased libido and 3 decreased erectile/ejaculatory function. Serum low-density lipoprotein cholesterol, weight (~2 kg), hematocrit, and hemoglobin increased and serum high-density lipoprotein cholesterol decreased in both 11ß-MNTDC groups. CONCLUSION: Daily oral 11ß-MNTDC for 28 days in healthy men markedly suppressed serum gonadotropin and T concentrations without serious adverse effects. These results warrant further evaluation of 11ß-MNTDC as a potential male oral contraceptive.


Assuntos
Estrenos/administração & dosagem , Gonadotropinas/sangue , Administração Oral , Adolescente , Adulto , Anticoncepção/métodos , Anticoncepcionais Masculinos/administração & dosagem , Anticoncepcionais Masculinos/efeitos adversos , Anticoncepcionais Masculinos/farmacocinética , Método Duplo-Cego , Regulação para Baixo/efeitos dos fármacos , Esquema de Medicação , Estrenos/efeitos adversos , Estrenos/farmacocinética , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Cancer Res ; 67(10): 5033-41, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17510436

RESUMO

Androgen deprivation therapy (ADT) remains the primary treatment for advanced prostate cancer. The efficacy of ADT has not been rigorously evaluated by demonstrating suppression of prostatic androgen activity at the target tissue and molecular level. We determined the efficacy and consistency of medical castration in suppressing prostatic androgen levels and androgen-regulated gene expression. Androgen levels and androgen-regulated gene expression (by microarray profiling, quantitative reverse transcription-PCR, and immunohistochemistry) were measured in prostate samples from a clinical trial of short-term castration (1 month) using the gonadotropin-releasing hormone antagonist, Acyline, versus placebo in healthy men. To assess the effects of long-term ADT, gene expression measurements were evaluated at baseline and after 3, 6, and 9 months of neoadjuvant ADT in prostatectomy samples from men with localized prostate cancer. Medical castration reduced tissue androgens by 75% and reduced the expression of several androgen-regulated genes (NDRG1, FKBP5, and TMPRSS2). However, many androgen-responsive genes, including the androgen receptor (AR) and prostate-specific antigen (PSA), were not suppressed after short-term castration or after 9 months of neoadjuvant ADT. Significant heterogeneity in PSA and AR protein expression was observed in prostate cancer samples at each time point of ADT. Medical castration based on serum testosterone levels cannot be equated with androgen ablation in the prostate microenvironment. Standard androgen deprivation does not consistently suppress androgen-dependent gene expression. Suboptimal suppression of tumoral androgen activity may lead to adaptive cellular changes allowing prostate cancer cell survival in a low androgen environment. Optimal clinical efficacy will require testing of novel approaches targeting complete suppression of systemic and intracrine contributions to the prostatic androgen microenvironment.


Assuntos
Androgênios/fisiologia , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , Neoplasias da Próstata/terapia , Testosterona/antagonistas & inibidores , Adulto , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Análise de Sequência com Séries de Oligonucleotídeos , Oligopeptídeos/uso terapêutico , Orquiectomia/métodos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Testosterona/sangue
8.
J Clin Endocrinol Metab ; 104(2): 423-432, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30252061

RESUMO

Context: Dimethandrolone (DMA) has androgenic and progestational activity. Single oral doses of DMA undecanoate (DMAU) were well tolerated and reversibly suppressed serum LH and testosterone (T) in men. Objective: Assess safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of oral DMAU. Design: Double-blind, randomized, placebo-controlled study. Setting: Two academic medical centers. Participants: Healthy men (18 to 50 years). Interventions: One hundred men received DMAU [0, 100, 200, or 400 mg, formulated in castor oil/benzyl benzoate (C) or powder (P)] for 28 days. Subjects underwent 24-hour PK sampling on days 1 and 28 and twice weekly ambulatory visits throughout treatment. Main Outcome Measures: Primary outcomes were safety and tolerability parameters (vitals, laboratory data, mood, and sexual function scores) and adverse events. Secondary outcomes were drug PK profiles and PD effects (serum LH, FSH, and sex hormones). Results: Eighty-two subjects completed the study and were included in the analysis. There were no serious adverse events. No clinically significant changes developed in safety laboratory parameters. A significant dose effect was seen for weight, hematocrit, high-density lipoprotein cholesterol, corrected QT interval, and sexual desire. Serum 24-hour average concentrations of DMAU and DMA showed dose-related increases (P < 0.001). All six subjects in the P400 group and 12 of 13 subjects in the C400 group achieved marked suppression of LH and FSH (<1.0 IU/L) and serum T (<50 ng/dL). Conclusions: Daily oral administration of DMAU for 28 days in healthy men is well tolerated. Doses of ≥200 mg markedly suppress serum T, LH, and FSH. These results support further testing of DMAU as a male contraceptive.


Assuntos
Anticoncepcionais Masculinos/administração & dosagem , Drogas em Investigação/administração & dosagem , Nandrolona/análogos & derivados , Administração Oral , Adulto , Anticoncepcionais Masculinos/efeitos adversos , Anticoncepcionais Masculinos/farmacocinética , Relação Dose-Resposta a Droga , Método Duplo-Cego , Drogas em Investigação/efeitos adversos , Drogas em Investigação/farmacocinética , Hormônio Foliculoestimulante/sangue , Voluntários Saudáveis , Humanos , Hormônio Luteinizante/sangue , Masculino , Nandrolona/administração & dosagem , Nandrolona/efeitos adversos , Nandrolona/farmacocinética , Placebos/administração & dosagem , Placebos/efeitos adversos , Testosterona/sangue , Adulto Jovem
9.
J Clin Endocrinol Metab ; 104(3): 629-638, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30252057

RESUMO

Context: 11ß-Methyl-19-nortestosterone-17ß-dodecylcarbonate (11ß-MNTDC) is an orally bioavailable prodrug of 11ß-methyl-19-nortestosterone (11ß-MNT) with androgenic and progestational activity. Objectives: (i) Quantify 11ß-MNT binding to androgen and progesterone receptors. (ii) Evaluate safety, tolerability, and serum gonadotropin and testosterone suppression by 11ß-MNTDC in men. Design and Setting: (i) In vitro receptor binding and transactivation studies and (ii) randomized, double-blind, placebo-controlled single-dose, dose-escalating phase I study at two academic medical centers. Participants and Intervention: Twelve healthy male volunteers were randomized (five active, one placebo) to escalating single oral doses (100, 200, 400, and 800 mg) of 11ß-MNTDC or placebo given with or without food. Main Outcome Measures: (i) In vitro 11ß-MNT/11ß-MNTDC human receptor binding and transactivation and (ii) safety and tolerability, pharmacokinetics, and quantification of serum gonadotropin and testosterone concentrations for 24 hours following dosing. Results: 11ß-MNT avidly binds and activates human androgen and progesterone receptors, but 11ß-MNTDC has minimal activity. Single oral doses of 11ß-MNTDC were well tolerated without serious adverse events. Administration of 11ß-MNTDC with food markedly increased average 11ß-MNTDC and 11ß-MNT serum concentrations (P < 0.001 for all doses) compared with fasting with a significant dose-related effect on average serum drug concentrations (P < 0.0001). The 200-, 400-, and 800-mg doses significantly suppressed average serum testosterone concentrations (P < 0.05). Conclusions: A single, oral dose of 11ß-MNTDC up to 800 mg administered with food is safe and well tolerated in healthy men. The active drug 11ß-MNT has androgenic and progestational activity, rapidly suppresses serum testosterone, and is a promising candidate for an effective once-daily oral male hormonal contraceptive.


Assuntos
Anticoncepcionais Masculinos/administração & dosagem , Nandrolona/análogos & derivados , Administração Oral , Adulto , Disponibilidade Biológica , Anticoncepcionais Masculinos/efeitos adversos , Anticoncepcionais Masculinos/farmacocinética , Relação Dose-Resposta a Droga , Método Duplo-Cego , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Nandrolona/administração & dosagem , Nandrolona/efeitos adversos , Nandrolona/farmacocinética , Receptores Androgênicos/metabolismo , Receptores de Progesterona/metabolismo , Adulto Jovem
10.
J Clin Endocrinol Metab ; 93(5): 1774-83, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18303073

RESUMO

CONTEXT: Male hormonal contraceptive methods require effective suppression of sperm output. OBJECTIVE: The objective of the study was to define the covariables that influence the rate and extent of suppression of spermatogenesis to a level shown in previous World Health Organization-sponsored studies to be sufficient for contraceptive purposes (< or =1 million/ml). DESIGN: This was an integrated analysis of all published male hormonal contraceptive studies of at least 3 months' treatment duration. SETTING: Deidentified individual subject data were provided by investigators of 30 studies published between 1990 and 2006. PARTICIPANTS: A total of 1756 healthy men (by physical, blood, and semen exam) aged 18-51 yr of predominantly Caucasian (two thirds) or Asian (one third) descent were studied. This represents about 85% of all the published data. INTERVENTION(S): Men were treated with different preparations of testosterone, with or without various progestins. MAIN OUTCOME MEASURE: Semen analysis was the main measure. RESULTS: Progestin coadministration increased both the rate and extent of suppression. Caucasian men suppressed sperm output faster initially but ultimately to a less complete extent than did non-Caucasians. Younger age and lower initial blood testosterone or sperm concentration were also associated with faster suppression, but the independent effect sizes for age and baseline testicular function were relatively small. CONCLUSION: Male hormonal contraceptives can be practically applied to a wide range of men but require coadministration of an androgen with a second agent (i.e. progestin) for earlier and more complete suppression of sperm output. Whereas considerable progress has been made toward defining clinically effective combinations, further optimization of androgen-progestin treatment regimens is still required.


Assuntos
Anticoncepcionais Masculinos/farmacologia , Progestinas/administração & dosagem , Espermatogênese/efeitos dos fármacos , Testosterona/administração & dosagem , Adolescente , Adulto , Povo Asiático , Índice de Massa Corporal , Humanos , Masculino , Pessoa de Meia-Idade , População Branca
12.
J Urol ; 179(6): 2333-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18423697

RESUMO

PURPOSE: Dutasteride and finasteride are 5alpha-reductase inhibitors that dramatically decrease serum levels of dihydrotestosterone. Because androgens affect bone, lipids, hematopoiesis, prostate and sexual function, we determined the impact of 5alpha-reductase inhibitors on these end points. MATERIALS AND METHODS: We conducted a randomized, double-blinded, placebo controlled trial of 99 men 18 to 55 years old randomly assigned to receive 0.5 mg dutasteride (33), 5 mg finasteride (34) or placebo (32) daily for 1 year. Bone mineral density was measured at baseline, after 1 year of treatment and 6 months after drug discontinuation. In addition, markers of bone turnover, fasting serum lipoprotein concentrations, hemoglobin and prostate specific antigen were measured at baseline, after 26 and 52 weeks of treatment, and again 24 weeks after drug discontinuation. Sexual function was assessed at these points by a validated questionnaire. RESULTS: Significant suppression of circulating dihydrotestosterone levels with the administration of dutasteride or finasteride did not significantly affect bone mineral density or markers of bone metabolism. Similarly serum lipoproteins and hemoglobin were unaffected. Serum prostate specific antigen and self-assessed sexual function decreased slightly during treatment with both 5alpha-reductase inhibitors but returned to baseline during followup. CONCLUSIONS: Profound suppression of circulating serum dihydrotestosterone induced by 5alpha-reductase inhibitors during 1 year does not adversely impact bone, serum lipoproteins or hemoglobin, and has a minimal, reversible effect on serum prostate specific antigen and sexual function in normal men. Circulating dihydrotestosterone does not appear to have a clinically significant role in modulating bone mass, hematopoiesis or lipid metabolism in normal men.


Assuntos
Azasteroides/farmacologia , Densidade Óssea/efeitos dos fármacos , Colestenona 5 alfa-Redutase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Finasterida/farmacologia , Hemoglobinas/análise , Hemoglobinas/efeitos dos fármacos , Lipoproteínas/sangue , Lipoproteínas/efeitos dos fármacos , Antígeno Prostático Específico/sangue , Antígeno Prostático Específico/efeitos dos fármacos , Sexualidade/efeitos dos fármacos , Adolescente , Adulto , Método Duplo-Cego , Dutasterida , Humanos , Masculino , Pessoa de Meia-Idade
13.
J Androl ; 29(2): 222-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18077826

RESUMO

Oral androgen development has been hampered by the rapid metabolism of orally administered testosterone (T) and low bioavailibility. The addition of the 5alpha-reductase inhibitor dutasteride (D) to oral T in oil dramatically improves concentrations of serum T. In this study we evaluate the absorption of oral T+D, comparing nanomilled T (NmT+D) vs T dissolved in oil (Capmul; CpT+D), as nanomilling might offer a simpler, more practical means of oral T administration, given the limited solubility of T in oil. Twelve healthy men were administered leuprolide on Day -14 to suppress endogenous T biosynthesis and were pretreated with D to block 5alpha-reductase. Once hypogonadal, subjects were sequentially administered 200- and 400-mg doses of CpT+D and NmT+D in the fasted and fed states. Serum T and dihydrotestosterone (DHT) were measured: before dose and at 0.5, 1, 2, 3, 4, 6, 8, 10, 12, and 24 hours after each dose. Two weeks after leuprolide administration, T levels were below the normal range. A 400-mg dose of either formulation of oral T+D increased mean serum T above the lower limit of the normal range for 8-10 hours. Food had a minimal effect on the pharmacokinetic parameters of the NmT+D formulation but decreased the maximum observed concentration after dosing (C(max)) for CpT+D. Serum DHT remained below the normal range throughout the study period with both formulations. No significant changes in liver function tests or other adverse events were observed. A 400-mg dose of either oral T+D formulation normalized serum T for 8-10 hours and suppressed DHT. NmT allows for tablet formulation, and its pharmacokinetics were not affected by food, demonstrating the feasibility of oral nanomilled T as a promising and practical twice-daily therapy for the treatment of male hypogonadism.


Assuntos
Azasteroides/farmacologia , Hipogonadismo , Testosterona/administração & dosagem , Testosterona/sangue , Administração Oral , Adolescente , Adulto , Di-Hidrotestosterona/farmacocinética , Dutasterida , Humanos , Hipogonadismo/induzido quimicamente , Hipogonadismo/tratamento farmacológico , Leuprolida , Masculino , Pessoa de Meia-Idade
14.
Asian J Androl ; 10(2): 193-200, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18097527

RESUMO

AIM: To study the relationship between circulating androgens (total testosterone [TT], free testosterone [fT] and dihydrotestosterone [DHT]) and high-density lipoprotein cholesterol (HDL-C) in men with and without cardiovascular disease (CVD). METHODS: Cross-sectional analyses included 1 661 baseline samples from the Massachusetts Male Aging Study (MMAS), a population-based cohort of men ages 40-70 years. Serum hormones were measured by radioimmunoassay and HDL-C was determined following precipitation of the lower density lipoproteins. CVD was determined by self-report. Analyses were performed using multiple linear regression. RESULTS: TT and HDL-C were positively correlated in the entire sample (r=0.11, P=0.0001). After adjusting for confounders, we found this relationship was mostly limited to the 209 men with CVD. Among men with CVD, TT (P=0.0004), fT (P=0.0172) and DHT (P=0.0128) were all positively correlated with HDL-C, whereas in men without CVD only TT correlated with HDL-C (P=0.0099). CONCLUSION: Our results suggest that if androgens contribute to CVD in middle-aged men, the effect is not related to a suppressive effect of endogenous T on HDL-C.


Assuntos
Doenças Cardiovasculares/sangue , HDL-Colesterol/sangue , Testosterona/sangue , Adulto , Idoso , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade
15.
Arch Intern Med ; 167(12): 1252-60, 2007 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-17592098

RESUMO

BACKGROUND: Sex steroid levels are related to metabolic outcomes that could convey higher risk of premature death. METHODS: We examined whether total or free testosterone, dihydrotestosterone, and sex hormone-binding globulin levels are related to all-cause or cause-specific mortality in men. Data were obtained from the Massachusetts Male Aging Study, a population-based cohort study of 1709 men aged 40 to 70 years. Men were followed up for all-cause and cause-specific mortality. RESULTS: Complete data were available for 1686 men, with 395 deaths occurring during 15.3 years of follow-up. With age adjustment, dihydrotestosterone and sex hormone-binding globulin levels were associated with ischemic heart disease mortality, and free testosterone level was associated with respiratory mortality. In multivariate-adjusted models, higher free testosterone (P=.02) and lower dihydrotestosterone (P=.04) levels were significantly associated with ischemic heart disease mortality, although the latter association was not robust to differences in model selection. The relative risk of death from ischemic heart disease per 1-SD lower free testosterone level was 0.80 (95% confidence interval, 0.64-0.99). Free testosterone level was significantly associated with respiratory mortality (P=.002), with a multivariate-adjusted relative risk per 1-SD lower free testosterone level of 1.90 (95% confidence interval, 1.24-2.92). Total testosterone level was unrelated to mortality, and sex hormone-binding globulin was not significantly associated with mortality after multivariate adjustment. CONCLUSIONS: In men, endogenous sex steroid levels seem to have relatively weak associations with mortality. These data provide little support for the hypothesis that endogenous sex steroid levels are associated with risk of premature death but suggest that further investigation of the relationship between sex steroids and mortality from ischemic heart disease and respiratory disease may be warranted.


Assuntos
Di-Hidrotestosterona/sangue , Isquemia Miocárdica/mortalidade , Neoplasias/mortalidade , Doenças Respiratórias/mortalidade , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue , Adulto , Idoso , Biomarcadores/sangue , Causas de Morte , Seguimentos , Humanos , Masculino , Massachusetts/epidemiologia , Pessoa de Meia-Idade , Análise Multivariada , Isquemia Miocárdica/sangue , Neoplasias/sangue , Radioimunoensaio , Doenças Respiratórias/sangue
16.
J Clin Endocrinol Metab ; 92(5): 1659-65, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17299062

RESUMO

CONTEXT: Dutasteride and finasteride are 5alpha-reductase inhibitors (5ARIs) that dramatically reduce serum levels of dihydrotestosterone (DHT). OBJECTIVE: Because androgens are essential for fertility, we sought to determine the impact of 5ARI administration on serum testosterone (T), DHT, and spermatogenesis. DESIGN, SETTING, SUBJECTS, AND INTERVENTION: We conducted a randomized, double-blinded, placebo-controlled trial in 99 healthy men randomly assigned to receive dutasteride (D; 0.5 mg) (n = 33), finasteride (F; 5 mg) (n = 34), or placebo (n = 32) once daily for 1 yr. MAIN OUTCOME MEASURES: Blood and semen samples were collected at baseline and 26 and 52 wk of treatment and 24 wk after treatment and were assessed for T, DHT, and semen parameters. RESULTS: D and F significantly (P < 0.001) suppressed serum DHT, compared with placebo (D, 94%; F, 73%) and transiently increased serum T. In both treatment groups, total sperm count, compared with baseline, was significantly decreased at 26 wk (D, -28.6%; F, -34.3%) but not at 52 wk (D, -24.9%; F, -16.2%) or the 24-wk follow-up (D, -23.3%; F, -6.2%). At 52 wk, semen volume was decreased (D, -29.7%; F, -14.5%, significantly for D) as was sperm concentration (D, -3.2%; [corrected] F, -7.4%, neither significant). There was a significant reduction of -6 to 12% in sperm motility during treatment with both D and F and at follow-up. Neither treatment had any effect on sperm morphology. CONCLUSIONS: This study demonstrates that the decrease in DHT induced by 5ARIs is associated with mild decreases in semen parameters that appear reversible after discontinuation.


Assuntos
Inibidores de 5-alfa Redutase , Azasteroides/farmacologia , Inibidores Enzimáticos/farmacologia , Finasterida/farmacologia , Hormônios/sangue , Sêmen/efeitos dos fármacos , Adolescente , Adulto , Método Duplo-Cego , Dutasterida , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/ultraestrutura
17.
J Androl ; 28(5): 734-41, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17494097

RESUMO

Male hormonal contraceptive regimens function by suppressing gonadotropin secretion, resulting in a dramatic decrease in testicular androgen biosynthesis and spermatogenesis. Animal studies suggest that persistent intratesticular (iT)-androgen production has a stimulatory effect on spermatogenesis in the setting of gonadotropin suppression. We hypothesized that men with incompletely suppressed spermatogenesis (>1,000,000 sperm/mL) during male hormonal contraceptive treatment would have higher iT-androgen concentrations than men who achieved severe oligospermia (

Assuntos
Di-Hidrotestosterona/metabolismo , Gonadotropinas/antagonistas & inibidores , Bloqueadores de Espermatogênese/farmacologia , Espermatogênese/efeitos dos fármacos , Testículo/metabolismo , Testosterona/metabolismo , Adulto , Di-Hidrotestosterona/sangue , Gonadotropinas/sangue , Humanos , Masculino , Testosterona/sangue , Falha de Tratamento
18.
J Androl ; 28(4): 548-54, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17314233

RESUMO

The administration of testosterone plus a progestogen functions as a male contraceptive by inhibiting the release of pituitary gonadotropins. After 3 to 4 months of treatment, most men are azoospermic or severely oligospermic (< or =1 million sperm/mL). However, 10% to 20% of men have persistent sperm production despite profound gonadotropin suppression. Since insulin-like factor 3 (INSL3) has been shown to prevent germ cell apoptosis in mice, we hypothesized that INSL3 might be higher in men with persistent spermatogenesis during treatment with male hormonal contraceptives. In a retrospective analysis, we measured serum INSL3 in 107 men from 3 recent male hormonal contraceptive studies and determined the relationship between suppression of spermatogenesis and serum INSL3. At the end of treatment 63 men (59%) were azoospermic and 44 men (41%) had detectable sperm in their ejaculates. Baseline INSL3 did not predict azoospermia; however, end of treatment serum INSL3 was significantly higher in nonazoospermic men compared with those with azoospermia (median [interquartile range]: 95 [73-127] pg/mL vs 80 [67-101] pg/mL; P = .03). Furthermore, serum INSL3 was positively correlated with sperm concentration (r = .25; P = .009) at the end of treatment and was significantly associated with nonazoospermia by multivariate logistic regression (P = .03). After 6 months of treatment with a hormonal male contraceptive regimen, higher serum INSL3 concentrations were associated with persistent sperm production. INSL3 may play a role in preventing complete suppression of spermatogenesis in some men on hormonal contraceptive regimens. This finding suggests that INSL3 may be a potential target for male contraceptive development.


Assuntos
Anticoncepcionais Masculinos , Insulina/sangue , Espermatogênese/fisiologia , Biomarcadores/sangue , Humanos , Masculino , Proteínas , Radioimunoensaio , Valores de Referência , Estudos Retrospectivos , Contagem de Espermatozoides , Espermatogênese/efeitos dos fármacos , Falha de Tratamento
19.
Contraception ; 75(3): 218-23, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17303493

RESUMO

BACKGROUND: Testosterone (T) gel, administered transdermally in combination with injections of depomedroxyprogesterone acetate (DMPA) every 3 months, results in effective suppression of spermatogenesis in 90% of men. Men's attitudes regarding the daily self-administration of T-gel and the impact of such a regimen on sexual function, however, are unknown. Therefore, we questioned subjects enrolled in a combination T-gel plus DMPA male contraceptive trial regarding the acceptability of T-gel for male contraception and the impact of the T-gel/DMPA regimen on sexual function and satisfaction during treatment. STUDY DESIGN: Thirty-eight healthy men, ages 18-55, were treated with T-gel (100 mg daily) + DMPA (300 mg every 3 months) for 24 weeks. Sexual function was assessed using a validated questionnaire at baseline, after 12 and 24 weeks of treatment and 12 weeks into recovery. The overall acceptability of the method and attitudes regarding the daily self-administration of T-gel were assessed by a questionnaire 12 weeks into recovery. RESULTS: Fifty percent of subjects were either satisfied or very satisfied with the T-gel-based contraceptive regimen, and 45% indicated they would use the regimen if it were commercially available. The T-gel was found to be easy to use by 76% of men, but a third of subjects felt that T-gel administration interfered with their daily routine. Sexual function was largely preserved during treatment; however, slight decreases in sexual function were noted during recovery. CONCLUSIONS: The experimental male hormonal contraceptive regimen of T-gel + DMPA is acceptable to approximately one half of study volunteers, most of whom would use the method if it were commercially available. Given its appeal to a significant proportion of men, additional studies using T-gel and DMPA for male contraception are warranted.


Assuntos
Anticoncepcionais Masculinos/farmacologia , Acetato de Medroxiprogesterona/farmacologia , Satisfação do Paciente , Testosterona/farmacologia , Administração Tópica , Adolescente , Adulto , Androgênios/efeitos adversos , Androgênios/farmacologia , Coito/fisiologia , Anticoncepcionais Masculinos/efeitos adversos , Combinação de Medicamentos , Humanos , Injeções Subcutâneas , Masculino , Acetato de Medroxiprogesterona/efeitos adversos , Pessoa de Meia-Idade , Contagem de Espermatozoides , Espermatogênese/efeitos dos fármacos , Inquéritos e Questionários , Testosterona/efeitos adversos
20.
J Clin Endocrinol Metab ; 91(3): 843-50, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16394089

RESUMO

BACKGROUND: The metabolic syndrome (MetS), characterized by central obesity, lipid and insulin dysregulation, and hypertension, is a precursor state for cardiovascular disease. The purpose of this analysis was to determine whether low serum sex hormone levels or clinical androgen deficiency (AD) predict the development of MetS. METHODS: Data were obtained from the Massachusetts Male Aging Study, a population-based prospective cohort of 1709 men observed at three time points (T1, 1987-1989; T2, 1995-1997; T3, 2002-2004). MetS was defined using a modification of the ATP III guidelines. Clinical AD was defined using a combination of testosterone levels and clinical signs and symptoms. The association between MetS and sex hormone levels or clinical AD was assessed using relative risks (RR), and 95% confidence intervals (95% CI) were estimated using Poisson regression models. RESULTS: Analysis was conducted in 950 men without MetS at T1. Lower levels of total testosterone and SHBG were predictive of MetS, particularly among men with a body mass index (BMI) below 25 kg/m2 with adjusted RRs for a decrease in 1 sd of 1.41 (95% CI, 1.06-1.87) and 1.65 (95% CI, 1.12-2.42). Results were similar for the AD and MetS association, with RRs of 2.51 (95% CI, 1.12-5.65) among men with a BMI less than 25 compared with an RR of 1.22 (95% CI, 0.66-2.24) in men with a BMI of 25 or greater. CONCLUSIONS: Low serum SHBG, low total testosterone, and clinical AD are associated with increased risk of developing MetS over time, particularly in nonoverweight, middle-aged men (BMI, <25). Together, these results suggest that low SHBG and/or AD may provide early warning signs for cardiovascular risk and an opportunity for early intervention in nonobese men.


Assuntos
Androgênios/deficiência , Doenças Cardiovasculares/epidemiologia , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue , Adulto , Idoso , Peso Corporal , Estudos de Coortes , Humanos , Masculino , Massachusetts , Pessoa de Meia-Idade , Valores de Referência , Fatores Socioeconômicos
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