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1.
Andrology ; 7(6): 878-887, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30969032

RESUMO

BACKGROUND: Novel male-based contraceptives are needed to broaden family planning choices. A progestin, Nestorone® (Nes) gel, plus a testosterone (T) gel suppresses sperm concentrations to levels associated with effective contraception in normal men. However, administration of two gels on different parts of the body daily is impractical. OBJECTIVE: Compare the effectiveness of daily application of a single, combined 8.3 mg Nes-62.5 mg T gel (Nes-T) vs. 62.7 mg T gel to suppress serum FSH and LH concentrations to ≤1.0 IU/L (a threshold associated with suppression of sperm concentrations to ≤1 million and effective contraception) and to compare the pharmacokinetics of serum Nes and T concentrations between the gel groups. DESIGN: We conducted a 28-day, double-blind, controlled trial of 44 healthy men randomized to daily Nes-T or T gel with measurement of hormones at baseline, treatment, and recovery and during 24-h pharmacokinetic studies on days 1 and 28 of treatment. RESULTS: Of the subjects who met pre-defined inclusion criteria, 84% of the Nes-T group suppressed serum gonadotropin concentrations to ≤1.0 IU/L at days 21-28 vs. 16.7% in the T group (p < 0.001). On day 1, Nes concentrations rose significantly above baseline by 2 h and continued to rise up to 24 h after Nes-T gel application. Nes concentrations were not detectable in the T group. Serum total T concentrations rose and were significantly higher in the T gel group compared to the Nes-T group at 24 h on day 1 and days 11, 14, and 21 (p < 0.01). There were no serious adverse events in either group. About 80% of the subjects reported satisfaction with both gels. CONCLUSION: Daily Nes-T gel effectively and safely suppresses serum gonadotropins and is acceptable to most men. It should be studied further in efficacy trials of hormonal male contraception.


Assuntos
Contraceptivos Hormonais/farmacologia , Anticoncepcionais Masculinos/farmacologia , Gonadotropinas/sangue , Norprogesteronas/farmacologia , Testosterona/farmacologia , Adolescente , Adulto , Contraceptivos Hormonais/farmacocinética , Anticoncepcionais Masculinos/farmacocinética , Método Duplo-Cego , Combinação de Medicamentos , Hormônio Foliculoestimulante/sangue , Contracepção Hormonal , Humanos , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Norprogesteronas/farmacocinética , Contagem de Espermatozoides , Espermatogênese/efeitos dos fármacos , Inquéritos e Questionários , Testosterona/farmacocinética , Congêneres da Testosterona/farmacologia , Adulto Jovem
2.
Andrology ; 7(2): 235-243, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30556332

RESUMO

BACKGROUND: Testosterone (T)/Nestorone (NES) combination gel is a potential transdermal male contraceptive that suppresses gonadotropins and spermatogenesis. Transfer of transdermal T from men to women can be prevented by washing or covering application sites with clothing. OBJECTIVES: We hypothesized that showering or wearing a shirt over gel application sites would prevent secondary exposure of T and NES to a woman after close skin contact. MATERIALS AND METHODS: Twelve healthy male and 12 healthy female participants were recruited. Men applied T/NES 62 mg/8 mg gel to their shoulders and upper arms. Two hours after application, female partners rubbed the application site for 15 min. Exposure in the female partner was assessed under three conditions: a shirt covered the application site; the man showered prior to skin contact; or without intervention to reduce transfer. Serum T and NES concentrations were measured by LC-MS/MS in serial blood samples for 24 h after gel exposure. MAIN OUTCOMES: Change in female serum T and NES levels as measured by average concentration over 24 h (Cavg ). RESULTS: Median female serum T Cavg was 23.9 ng/dL (interquartile range, 19.3, 33.9) with the shirt barrier and 26.7 ng/dL (20.7, 33.9) after showering, which was higher than baseline 20.9 ng/dL (16.7, 25.0), both p < 0.03) but lower than without intervention (58.2 ng/dL [30.9, 89.1], both p < 0.01). Female serum NES Cavg and maximum concentration were below the lower limit of quantification with the shirt barrier and after showering, but increased without intervention in six of 12 women (maximum concentration <60 pg/mL). Men had lower average serum NES levels after showering (47 pg/ml [20, 94] compared to no intervention (153.3 pg/mL [51, 241], p < 0.02). CONCLUSION: Secondary transfer of T and NES occurs after intensive skin contact with the gel application site. Secondary transfer is decreased by a shirt barrier or showering before contact.


Assuntos
Anticoncepcionais Masculinos/administração & dosagem , Anticoncepcionais Masculinos/farmacocinética , Norprogesteronas/administração & dosagem , Norprogesteronas/farmacocinética , Testosterona/administração & dosagem , Testosterona/farmacocinética , Adulto , Feminino , Géis , Humanos , Masculino , Pele
3.
Clin Endocrinol (Oxf) ; 84(5): 672-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26663024

RESUMO

OBJECTIVE: Diurnal salivary cortisol patterns in healthy adults are well established but have not been studied in midlife women with hot flashes. We hypothesized that frequent hot flashes are associated with aberrant cortisol patterns similar to sleep-deficient individuals. DESIGN: Cross-sectional. PARTICIPANTS: A total of 306 women, ages 40-62, randomized to a behavioural intervention for hot flashes. MEASUREMENTS: Baseline comparisons of cortisol geometric means (nmol/l) from four daily time points averaged over two consecutive days plus other calculated cortisol measures were made between groups defined by baseline: (i) mean daily hot flash frequency tertile (≤5·5, N = 103; >5·5-8·8, N = 103; >8·8, N = 100) and (ii) selected characteristics. Repeated-measures linear regression models of log-transformed cortisol evaluated group differences, adjusting for covariates. RESULTS: Women were 67% White and 24% African American, with 7·6 (SD 3·9) hot flashes per day. Salivary cortisol geometric means (nmol/l) among all women were as follows: 75·0 (SD 44·8) total, 8·6 (SD 5·6) wake, 10·0 (SD 7·5) wake +30 min, 3·7 (SD 3·3) early afternoon and 1·6 (SD 1·8) bedtime. Wake + 30-minute values showed an 18% median rise from wake values (interquartile range -24 to 96%), and means varied by hot flash frequency tertile, from lowest to highest: 11·4(SD 7·3), 10·3 (SD 6·5) and 8·6 (SD 7·8), respectively, P = 0·003. Beside the early afternoon value (P = 0·02), cortisol values did not vary by hot flash frequency. CONCLUSION: Taken together, these findings suggest that high frequency of moderate-to-severe hot flashes may be associated with subtle abnormalities in cortisol concentrations - a pattern consistent with chronic sleep disturbance.


Assuntos
Exercício Físico/fisiologia , Ácidos Graxos Ômega-3/uso terapêutico , Fogachos/prevenção & controle , Hidrocortisona/análise , Saliva/química , Adulto , Ritmo Circadiano , Estudos Transversais , Feminino , Fogachos/metabolismo , Fogachos/fisiopatologia , Humanos , Modelos Lineares , Modelos Logísticos , Menopausa/fisiologia , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos
4.
J Clin Endocrinol Metab ; 98(3): 1198-206, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23348398

RESUMO

CONTEXT: The concentration of intratesticular testosterone (IT-T) required for human spermatogenesis is unknown because spermatogenesis can persist despite the markedly reduced IT-T concentrations observed with LH suppression. Methods to lower IT-T further are needed to determine the relationship between IT-T and spermatogenesis. OBJECTIVE: The objective of the study was to determine the effect of inhibiting the synthesis and metabolism of testosterone (T) on IT-T in gonadotropin-suppressed human testes. DESIGN/SETTING/PATIENTS: Forty normal men participated in a blinded, placebo-controlled, randomized trial at an academic center. INTERVENTION/OUTCOME MEASURES: All men were first administered the GnRH antagonist acyline to suppress LH. Forty-eight hours after acyline administration, subjects were randomly assigned to placebo, ketoconazole (to inhibit T synthesis) at 400 or 800 mg, dutasteride (to inhibit T metabolism) 2.5 mg, or anastrazole (to inhibit T metabolism) 1 mg, daily for 7 days (n = 8/group). Intratesticular steroid concentrations were measured 48 hours after acyline administration alone and again after 7 days of combination treatment. RESULTS: After 7 days of combination treatment, the median IT-T (25th, 75th percentile) in the placebo group was 14 (8.0, 21.2) ng/mL. IT-T was reduced to 3.7 (2.5, 7.1) ng/mL in the ketoconazole 400 mg group and 1.7 (0.8, 4.0) ng/mL in the ketoconazole 800 mg group (P < .001 vs placebo for both comparisons). IT-T concentrations in the dutasteride and anastrazole groups were similar to placebo. CONCLUSION: Combining inhibition of steroidogenesis with gonadotropin suppression lowers IT-T more than gonadotropin suppression alone. This combination might be useful to determine the minimum IT-T concentration necessary for human spermatogenesis, information essential for developing male hormonal contraceptives.


Assuntos
Androgênios/biossíntese , Anticoncepção/métodos , Cetoconazol/administração & dosagem , Oligopeptídeos/administração & dosagem , Testículo/efeitos dos fármacos , Inibidores de 14-alfa Desmetilase/administração & dosagem , 17-alfa-Hidroxiprogesterona/sangue , Adolescente , Adulto , Androgênios/sangue , Androstenodiona/biossíntese , Androstenodiona/sangue , Desidroepiandrosterona/biossíntese , Desidroepiandrosterona/sangue , Desenho de Fármacos , Sinergismo Farmacológico , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Espermatogênese/efeitos dos fármacos , Espermatogênese/fisiologia , Testículo/metabolismo , Testosterona/biossíntese , Testosterona/sangue , Adulto Jovem
5.
J Clin Endocrinol Metab ; 96(4): 1175-81, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21289266

RESUMO

INTRODUCTION: Concentrations of intratesticular (IT) testosterone (T) are known to be 100-200 times those of serum T; however, the IT concentrations of T's precursors, their testicular to serum gradients, gonadotropin dependence, and response to stimulation with human chorionic gonadotropin (hCG) have not been studied in detail. We hypothesized that serum and IT androstenedione (ADD) and IT dehydroepiandrosterone (DHEA) would be significantly suppressed by the administration of a GnRH antagonist and increased when stimulated by hCG, without a similar suppression of serum DHEA. METHODS: We suppressed gonadotropins in 23 normal men with the GnRH antagonist acyline and randomly assigned them to one of four doses of hCG, 0, 15, 60, or 125 IU sc every other day for 10 d. Blood and IT fluid for the measurement of serum and IT hormones were obtained at baseline and after 10 d of treatment. RESULTS: Baseline IT ADD [median (25th, 75th percentile)] was 629 (308, 860) nmol/liter, and IT DHEA was 564 (411, 879) nmol/liter, which were 175 and 27 times higher than their respective serum concentrations. IT ADD and IT DHEA were suppressed by 98 and 82%, respectively, by acyline and significantly increased with hCG administration. Likewise, serum ADD was suppressed by 50%, but serum DHEA was unchanged. DISCUSSION: ADD and DHEA are highly concentrated within the human testes compared with serum. Serum and IT ADD and IT DHEA are markedly suppressed with GnRH administration and stimulated by hCG, but serum DHEA is not, suggesting that most circulating DHEA is not of testicular origin.


Assuntos
Androstenodiona/metabolismo , Gonadotropina Coriônica/farmacologia , Desidroepiandrosterona/metabolismo , Gonadotropinas/farmacologia , Testículo/efeitos dos fármacos , Adolescente , Adulto , Androstenodiona/análise , Desidroepiandrosterona/análise , Relação Dose-Resposta a Droga , Antagonistas de Hormônios/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/farmacologia , Estimulação Química , Testículo/química , Testículo/metabolismo , Testosterona/análise , Testosterona/metabolismo , Suspensão de Tratamento , Adulto Jovem
6.
J Clin Endocrinol Metab ; 95(8): 3806-13, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20484472

RESUMO

CONTEXT AND OBJECTIVE: In men with infertility secondary to gonadotropin deficiency, treatment with relatively high dosages of human chorionic gonadotropin (hCG) stimulates intratesticular testosterone (IT-T) biosynthesis and spermatogenesis. Previously we found that lower dosages of hCG stimulated IT-T to normal. However, the minimal dose of hCG needed to stimulate IT-T and the dose-response relationship between very low doses of hCG and IT-T and serum testosterone in normal men is unknown. DESIGN, SETTING, PATIENTS, AND INTERVENTION: We induced experimental gonadotropin deficiency in 37 normal men with the GnRH antagonist acyline and randomized them to receive one of four low doses of hCG: 0, 15, 60, or 125 IU sc every other day or 7.5 g daily testosterone gel for 10 d. Testicular fluid was obtained by percutaneous aspiration for steroid measurements at baseline and after 10 d of treatment and correlated with contemporaneous serum hormone measurements. RESULTS: Median (25th, 75th percentile) baseline IT-T was 2508 nmol/liter (1753, 3502 nmol/liter). IT-T concentrations increased in a dose-dependent manner with very low-dosage hCG administration from 77 nmol/liter (40, 122 nmol/liter) to 923 nmol/liter (894, 1017 nmol/liter) in the 0- and 125-IU groups, respectively (P<0.001). Moreover, serum hCG was significantly correlated with both IT-T and serum testosterone (P<0.01). CONCLUSION: Doses of hCG far lower than those used clinically increase IT-T concentrations in a dose-dependent manner in normal men with experimental gonadotropin deficiency. Assessment of IT-T provides a valuable tool to investigate the hormonal regulation of spermatogenesis in man.


Assuntos
Gonadotropina Coriônica/farmacologia , Hormônio Foliculoestimulante/deficiência , Hormônio Luteinizante/deficiência , Sêmen/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testosterona/análise , Adolescente , Adulto , Análise de Variância , Cromatografia Líquida , Relação Dose-Resposta a Droga , Fluorimunoensaio , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Seleção de Pacientes , Sêmen/química
7.
J Androl ; 31(2): 138-45, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19779211

RESUMO

Sex steroids are essential for spermatogenesis; however, normal intratesticular concentrations of these hormones in man have not been extensively studied. To improve our understanding of intratesticular hormone concentrations, we performed bilateral testicular aspirations in a group of normal men, determined sex steroid concentrations within each testis, and compared these levels to serum hormone concentrations. Ten healthy human subjects aged 20-49 underwent bilateral testicular aspirations. Intratesticular hormone concentrations of testosterone, dihydrotestosterone (DHT), and estradiol were measured using liquid chromatography-tandem mass spectrometry. Intratesticular testosterone concentrations ranged from 119 to 1251 ng/mL, with a mean of 635 +/- 368 ng/mL. Intratesticular estradiol ranged from 0.41 to 3.9 ng/mL, with a mean of 2.4 +/- 1.3 ng/mL. Intratesticular DHT ranged from 1.1 to 7.9 ng/mL, with a mean of 3.5 +/- 3.2 ng/mL. Intratesticular testosterone and estradiol concentrations correlated highly with serum luteinizing hormone (LH; r = 0.87 and r = 0.70 respectively, P < .01). Intratesticular testosterone correlated highly with serum testosterone. Moreover, a significant correlation between the right and left testes was observed for testosterone (r = 0.82, P = .003), but not for estradiol or DHT. Intratesticular hormone concentrations can be safely assessed by testicular aspiration. Intratesticular testosterone and estradiol correlate highly with serum LH concentrations, and variation in serum LH accounts for most of the variation in intratesticular testosterone among men. In addition, intratesticular testosterone is highly correlated between testes in a given individual. Direct measurement of intratesticular testosterone will improve our understanding of the relationship between intratesticular sex steroids and spermatogenesis, and may have implications for the development of male hormonal contraception.


Assuntos
Di-Hidrotestosterona/análise , Estradiol/análise , Hormônio Luteinizante/sangue , Testículo/química , Testosterona/análise , Adulto , Cromatografia Líquida , Di-Hidrotestosterona/metabolismo , Estradiol/metabolismo , Hormônios Esteroides Gonadais/análise , Hormônios Esteroides Gonadais/metabolismo , Humanos , Masculino , Espectrometria de Massas , Testículo/metabolismo , Testosterona/metabolismo , Adulto Jovem
8.
Methods Inf Med ; 41(4): 277-81, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12425238

RESUMO

OBJECTIVES: Despite evidence documenting their ineffectiveness, sliding scale insulin is a commonly used regimen for glucose management for hospitalized patients with diabetes mellitus. At the Veterans Affairs Puget Sound Medical Center, where computer order entry has been mandated, we tested the hypothesis that an evidence-based minimal intervention order (supplemental insulin only when fasting serum glucoses exceeded 400 mg/dl) would decrease the use of sliding scale insulin orders. METHODS: Using a computerized order entry system, providers were initially offered a traditional sliding scale order or their own ad hoc orders for glycemic control of inpatients. After 34 weeks providers were offered a third option; a "minimal intervention order" with supplemental insulin only for glucose > 400 mg/dl. We extracted all regular insulin orders and performed a retrospective review of insulin sliding scale orders written between December 1, 1998 and November 16, 1999. We compared the frequency of traditional insulin sliding scale orders before and after the introduction of the minimal intervention order. RESULTS: Nearly all orders in the first 34 weeks were traditional insulin sliding scales. We found a significant decrease in the number of traditional insulin sliding scale orders in the 16 weeks after the introduction of a computerized quick-order for minimal intervention, from 978/1007 (97.1%) to 254/398 (63.8%) (P < 0.001). CONCLUSIONS: A simple, evidenced-based quick-order in a computer order entry system rapidly and significantly reduced use of sliding scale insulin regimens for glycemic control of inpatients.


Assuntos
Sistemas de Informação em Farmácia Clínica , Cetoacidose Diabética/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Equilíbrio Ácido-Base , Glicemia/análise , Cetoacidose Diabética/prevenção & controle , Esquema de Medicação , Prescrições de Medicamentos/estatística & dados numéricos , Hospitais de Veteranos , Humanos , Concentração de Íons de Hidrogênio , Sistemas Computadorizados de Registros Médicos/organização & administração , Sistemas de Medicação no Hospital , Estudos Retrospectivos , Washington
9.
J Clin Endocrinol Metab ; 87(7): 3090-6, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12107206

RESUMO

We examined the effects of sex steroids on cognitive functioning by exogenously manipulating circulating T levels in a group of healthy young men. Thirty-two men were randomized to receive 8 wk of treatment including: 1) im T enanthate 100 mg/wk plus daily oral placebo (T); 2) im placebo/wk plus 125 microg daily oral levonorgestrel (LNG); 3) im T enanthate 100 mg/wk plus 125 microg daily oral LNG (T + LNG); 4) im placebo/wk plus daily oral placebo. Cognitive functions were assessed at baseline and twice during treatment. Serum T and E2 levels were significantly increased in the T and T + LNG groups compared with baseline (P < 0.01) and T levels were significantly decreased in the LNG group (P < 0.05). Verbal memory significantly decreased in the LNG group (P < 0.01) and was maintained by coadministration of T in the T + LNG group. Divided attention was unaffected in the LNG group but improved significantly in the T + LNG group. In summary, decreased serum T levels induced by LNG or direct effects of the progestin, LNG, adversely affects verbal memory in normal young men. These results suggest that short-term changes in sex steroid levels have effects on cognitive function in healthy young men.


Assuntos
Cognição/efeitos dos fármacos , Anticoncepcionais Masculinos/administração & dosagem , Levanogestrel/administração & dosagem , Testosterona/análogos & derivados , Testosterona/administração & dosagem , Administração Oral , Adulto , Anticoncepcionais Masculinos/farmacologia , Estradiol/sangue , Humanos , Injeções Intramusculares , Levanogestrel/farmacologia , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Placebos , Testosterona/sangue , Testosterona/farmacologia , Fatores de Tempo
10.
J Androl ; 22(6): 1053-60, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11700852

RESUMO

Weekly intramuscular administration of testosterone esters such as testosterone enanthate (TE) suppresses gonadotropins and spermatogenesis and has been studied as a male contraceptive. For unknown reasons, however, some men fail to achieve azoospermia with such regimens. We hypothesized that either 1) daily circulating serum fluoroimmunoreactive gonadotropins were higher or testosterone levels were lower during the weekly injection interval, or 2) monthly circulating bioactive gonadotropin levels were higher in nonazoospermic men. We therefore analyzed daily testosterone and fluoroimmunoreactive gonadotropin levels as well as pooled monthly bioactive and fluoroimmunoreactive gonadotropin levels in normal men receiving chronic TE injections and correlated these levels with sperm production. After a 3-month control period, 51 normal men were randomly assigned to receive intramuscular TE at 25 mg (n = 10), 50 mg (n = 9), 100 mg (n = 10), 300 mg (n = 10), or placebo (n = 12) weekly for 6 months. After 5 months of testosterone administration, morning testosterone and fluoroimmunoreactive follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were measured daily for a 1-week period between TE injections. In addition, fluoroimmunoreactive and bioactive FSH and LH levels were measured in pooled monthly blood samples drawn just before the next TE injection. In the 100-mg and 300-mg TE groups, mean monthly fluoroimmunoreactive FSH and LH levels were suppressed by 86%-97%, bioactive FSH and LH levels by 62%-80%, and roughly half the subjects became azoospermic. In the 1-week period of month 6, daily testosterone levels between TE injections were within the normal range in men receiving placebo, or 25 or 50 mg of weekly TE, but were significantly elevated in men receiving 100 or 300 mg of weekly TE. At no point during treatment, however, were there significant differences in daily testosterone or fluoroimmunoreactive gonadotropin levels, or monthly bioactive gonadotropin levels between men achieving azoospermia and those with persistent spermatogenesis. This study, therefore, demonstrates that neither monthly nor daily differences in serum testosterone, or fluoroimmunoreactive or bioactive gonadotropins explain why some men fail to completely suppress their sperm counts to zero with weekly TE administration. Innate differences in the testicle's ability to maintain spermatogenesis in a low-gonadotropin environment may explain persistent spermatogenesis in some men treated with androgen-based contraceptive regimens.


Assuntos
Anticoncepcionais Masculinos , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Oligospermia/sangue , Testosterona/análogos & derivados , Testosterona/sangue , Testosterona/farmacologia , Adulto , Anticoncepcionais Masculinos/administração & dosagem , Anticoncepcionais Masculinos/farmacologia , Humanos , Injeções Intramusculares , Masculino , Valores de Referência , Sêmen/química , Testosterona/administração & dosagem
11.
Expert Opin Pharmacother ; 2(9): 1389-98, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11585019

RESUMO

As the world human population continues to explode, the need for effective, safe and convenient contraceptive methods escalates. Historically, women have borne the brunt of responsibility for contraception and family planning. Except for the condom, there are no easily reversible, male-based contraceptive options. Recent surveys have confirmed that the majority of men and women would consider using a hormonal male contraceptive if a safe, effective and convenient formulation were available. Investigators have sought to develop a male hormonal contraceptive based on the observation that spermatogenesis depends on stimulation by gonadotropins, follicle-stimulating hormone (FSH) and luteinising hormone (LH). Testosterone (T) and other hormones such as progestins suppress circulating gonadotropins and spermatogenesis and have been studied as potential male contraceptives. Results from two large, multi-centre trials demonstrated that high-dosage T conferred an overall contraceptive efficacy comparable to female oral contraceptives. This regimen was also fully reversible after discontinuation. However, this regimen was not universally effective and involved weekly im. injections that could be painful and inconvenient. In addition, the high dosage of T suppressed serum high-density lipoprotein (HDL) cholesterol levels, an effect that might increase atherogenesis. Investigators have attempted to develop a hormonal regimen that did not cause androgenic suppression of HDL cholesterol and that was uniformly effective by suppressing spermatogenesis to zero in all men. Studies of combination regimens of lower-dosage T and a progestin or a gonadotropin-releasing hormone analogue have demonstrated greater suppression of spermatogenesis than the WHO trials of high-dosage T but most of these regimens cause modest weight gain and suppression of serum HDL cholesterol levels. Overall, the data suggest that we are close to developing effective male hormonal contraceptives. The focus is now on developing effective oral regimens that could be safely taken daily or long-acting depot formulations of a male hormonal contraception that could be conveniently injected every 3 - 6 months. In this article, we shall review the exciting new developments in male hormonal contraception.


Assuntos
Anticoncepcionais Masculinos/farmacologia , Espermatogênese/efeitos dos fármacos , Anticoncepcionais Masculinos/química , Anticoncepcionais Orais Hormonais/química , Anticoncepcionais Orais Hormonais/farmacologia , Humanos , Masculino , Congêneres da Progesterona/química , Congêneres da Progesterona/farmacologia , Congêneres da Testosterona/química , Congêneres da Testosterona/farmacologia
12.
Endocrinol Metab Clin North Am ; 30(3): 647-69, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11571935

RESUMO

Aging is accompanied by gradual but progressive reductions in the secretion of testosterone and growth hormone in men, and by alterations in body composition and functional capacity that, to some degree, undo the effects of puberty. Preventing or reversing these changes with the use of trophic factors, including androgens, growth hormone, and growth hormone secretagogues, is an appealing prospect, but documenting the effectiveness of these interventions and their benefits and risks has proven to be a difficult undertaking that is far from complete. Small-scale clinical studies have shown that it is practicable to boost growth hormone and IGF-1 levels for periods of up to 12 months, and testosterone for up to 36 months, to reverse at least some age-related changes in body composition. Information regarding the effects of these interventions on strength, exercise capacity, and the ability to perform activities of daily living is still sparse, and additional reports from recently completed or currently ongoing clinical trials will not provide sufficient data to make firm conclusions. From the limited information currently available, androgen supplementation may be of benefit in some men aged more than 65 years, particularly in men with low serum testosterone levels (< 2 ng/mL). In this group, supplemental androgen therapy would be expected to increase lean body mass, bone mass, and possibly strength. In older men with testosterone levels between 2 and 3.5 ng/mL, some benefit might result from androgen supplementation, but it is not yet clear whether the benefits outweigh the risks. For men in this category, one might consider a 6- to 12-month trial of therapy after a full discussion and explicit consent, followed by a reassessment of the value of ongoing treatment. The even more limited data on growth hormone or growth hormone secretagogue interventions in aging do not support their general clinical use in healthy older men. Growth hormone is much more expensive than testosterone and is not covered by insurance for off-label uses. Patients who persistently seek a trial of therapy should be encouraged to enroll in a study if one is locally available. All of the growth hormone studies reported to date have focused, generally for reasons of safety, on healthy and robust groups of older subjects, men in whom the need for intervention is least compelling and in whom the functional effects of treatment may be the most difficult to observe. Phase II studies of intermediate size and duration examining prefrail groups of elderly who are at greater risk for functional loss and who stand to benefit the most from either preventive or restorative interventions are underway but are limited to the intermediate outcomes of body composition, strength, and function. Trials designed to assess clinically relevant final outcomes, such as falls, fractures, and institutionalization, are of necessity large-scale, long-term, and expensive. Support for larger phase III studies of growth hormone is unlikely to be forthcoming until the phase II studies are completed and show further promise. A multicenter clinical trial of testosterone is currently being planned under the joint sponsorship of the National Institute on Aging, the Veterans Health Administration, and industry, aimed at assessing the effects of testosterone on the risk for falls and fractures. The results of this trial and other large clinical trials should help to better define the balance of benefits and risks of trophic factor intervention in normal older men.


Assuntos
Envelhecimento/fisiologia , Androgênios/fisiologia , Hormônio do Crescimento Humano/fisiologia , Sistemas Neurossecretores/fisiologia , Androgênios/efeitos adversos , Androgênios/uso terapêutico , Hormônio do Crescimento/efeitos adversos , Hormônio do Crescimento/uso terapêutico , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/efeitos adversos , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Masculino
13.
Am J Med ; 111(4): 261-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11566455

RESUMO

PURPOSE: It is unclear whether intramuscular administration of testosterone esters to hypogonadal men is associated with changes in plasma lipids. We therefore analyzed 19 studies published between 1987 and 1999 that focused on male subjects with nonexperimental hypogonadism, treated subjects with an intramuscular testosterone ester and reported pretreatment and post-treatment concentrations of total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL) cholesterol, or total triglyceride. METHODS: We calculated study-specific, post-treatment minus pretreatment differences in each plasma lipid concentration (mean [95% confidence interval]). After testing of between-study homogeneity, we combined the study-specific differences. We then determined whether heterogeneity of differences could be explained in models of the differences on study and patient characteristics (mean +/- SE) before and after excluding extreme values using a multiple outlier procedure. RESULTS: The studies represented 272 hypogonadal men (age 44 +/- 4 years; 20% with hypergonadotropic hypogonadism; total testosterone 0.5 +/- 0.2 ng/mL) who received, on average, 179 +/- 13 mg intramuscular testosterone ester every 16 +/- 1 days for 6 +/- 1 months. Fixed-effects estimates of post-treatment minus pretreatment differences were -14 [-17 to -11] mg/dL (total cholesterol), -5 [-8 to -1] mg/dL (LDL cholesterol), -4 [-5 to -2] mg/dL (HDL cholesterol), and -1 [-6 to + 4] mg/dL (triglyceride). Decreases in HDL cholesterol were larger at lower dosages of testosterone ester (r = -0.54, P = 0.055), but were not explained by attrition, regression to the mean, dosing frequency or duration, concomitant elevation of plasma total testosterone, aromatization of testosterone to estradiol, or other study and patient characteristics. CONCLUSION: Intramuscular administration of testosterone esters to hypogonadal men is associated with a small, dosage-dependent decrease in HDL cholesterol and concomitant declines in total cholesterol and LDL cholesterol. The aggregate effect of these changes on cardiovascular risk remains unknown but deserves further study.


Assuntos
Hipogonadismo/tratamento farmacológico , Lipídeos/sangue , Testosterona/administração & dosagem , HDL-Colesterol/sangue , Relação Dose-Resposta a Droga , Humanos , Hipogonadismo/sangue , Injeções Intramusculares , Masculino
14.
Ann Med ; 33(9): 587-95, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11817653

RESUMO

New male contraceptive options are urgently needed. Safe, effective and fully reversible methods of male contraception would be useful for monogamous couples who are trying to regulate their family size. In addition, an effective male hormonal contraceptive that could be implanted or injected as a long-acting formulation every 3-6 months would be useful in countries where limiting population growth has become a public policy imperative. Male hormonal contraception is based on the same principles as traditional oestrogen-progestin female oral contraceptives. Both spermatogenesis and ovulation are dependent upon normal secretion of the pituitary gonadotropins, follicle stimulating hormone (FSH) and luteinizing hormone (LH). Exogenous gonadotropin-releasing hormone (GnRH) analogues and sex steroid hormones such as testosterone (T) and progestins suppress gonadotropins and spermatogenesis. Two large multicentre trials demonstrated that weekly administration of high-dosage T was very effective in suppressing gonadotropins and spermatogenesis and conferred an overall contraceptive efficacy comparable to female oral contraceptives. Studies of combination regimens of lower-dosage T plus a progestin or a GnRH analogue have demonstrated greater suppression of spermatogenesis than the World Health Organization trials of high-dosage T. Most of these male hormonal contraceptives have been associated with modest weight gain and suppression of serum high-density cholesterol (HDL) levels. In this article, we review the new developments in male hormonal contraception.


Assuntos
Anticoncepcionais Masculinos , Anticoncepcionais Orais Hormonais , Testosterona/análogos & derivados , Anabolizantes/farmacologia , HDL-Colesterol/sangue , Anticoncepcionais Masculinos/farmacologia , Anticoncepcionais Orais Hormonais/farmacologia , Preparações de Ação Retardada , Humanos , Masculino , Nandrolona/farmacologia , Testosterona/farmacologia
16.
Fertil Steril ; 74(4): 707-14, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11020511

RESUMO

OBJECTIVE: To test the hypothesis that oral desogestrel (DSG) plus testosterone would uniformly and rapidly suppress sperm concentrations in young men as effectively as levonorgestrel (LNG) plus testosterone and cause less high-density lipoprotein (HDL) suppression and weight gain. DESIGN: Single-blind, randomized trial. SETTING: VA Puget Sound and University of Washington, Seattle, Washington. PATIENT(S): Twenty-four healthy young men, aged 20-49. INTERVENTION(S): Subjects were randomized to three groups of men who were administered 6 months of therapy with oral DSG plus im testosterone enanthate: 150 microg of DSG plus 50 mg of testosterone (DSG 150-T 50), 150 microg of DSG plus 100 mg of testosterone (DSG 150-T 100) or 300 microg of DSG plus 100 mg of testosterone (DSG 300-T 100). We compared these three groups to two groups of historical controls of 100 mg of im testosterone alone or 150 microg of oral LNG plus 100 mg of im testosterone (LNG 125-T 100 group) enrolled in similar studies. MAIN OUTCOME MEASURE(S): Suppression of sperm counts to severe oligoazoospermia (sperm counts <1 x 10(6)/mL) and azoospermia, weight gain, and serum high-density cholesterol (HDL) suppression. RESULT(S): Azoospermia was achieved in all eight men receiving DSG 150-T 100 and seven of the eight men in the DSG 300-T 100 group. DSG 150 or 300 plus T 100 suppressed spermatogenesis as effectively as LNG 125-T 100 and more effectively than DSG 50-T 100 or testosterone alone. All groups tended to gain weight compared with their baseline, but the weight gain was greatest (and statistically significant) in the DSG 150-T 100, DSG 300-T 100, and LNG 125-T 100 groups. Serum HDL levels were modestly suppressed in all groups, and this effect was greatest in the DSG 300-T 100 and LNG 125-T 100 groups. CONCLUSION(S): The combination of DSG plus testosterone is a very effective regimen for suppression of spermatogenesis and has acceptably low side effects.


Assuntos
Anticoncepcionais Masculinos/farmacologia , Anticoncepcionais Orais Hormonais/farmacologia , Anticoncepcionais Orais Sintéticos/farmacologia , Desogestrel/farmacologia , Levanogestrel/farmacologia , Lipoproteínas HDL/sangue , Espermatogênese/efeitos dos fármacos , Testosterona/farmacologia , Aumento de Peso/efeitos dos fármacos , Acne Vulgar/induzido quimicamente , Adulto , Análise Química do Sangue , Colesterol/sangue , Ginecomastia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Oligospermia/induzido quimicamente , Contagem de Espermatozoides , Testosterona/sangue
17.
J Androl ; 20(3): 407-14, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10386821

RESUMO

Studies using exogenous high-dosage testosterone (T) or a combination regimen of physiologic T plus high-dosage levonorgestrel (LNG) administration in normal men have shown that oligoazoospermia (<3 million/mL) or azoospermia can be achieved in the majority of the men. However, these hormonal regimens have been associated with significant weight gain and suppression of serum high-density lipoprotein (HDL) cholesterol levels. We hypothesized that a combination of physiologic exogenous testosterone and lower dosage LNG would result in uniform severe oligoazoospermia or azoospermia in normal men but would cause fewer adverse metabolic side effects. We conducted a randomized, placebo-controlled, single-blind trial comparing 6 months of T enanthate (100 mg IM, weekly) plus LNG, 125 microg by mouth, daily (LNG 125; n = 18) or LNG, 250 microg by mouth, daily (LNG 250; n = 18) and compared these regimens with our previous study of the same dosage of T enanthate combined with placebo LNG (LNG 0; n = 18) or with 500 mg of LNG (LNG= 500; n = 18). All three combination regimens of T enanthate and LNG suppressed spermatogenesis more rapidly and resulted in significantly more uniform severe oligoazoospermia (<1 million/mL) than the T-alone regimen. Severe oligoazoospermia was achieved in 89% of the LNG 125, 89% of the LNG 250, and 78% of the LNG 500 groups, respectively, versus 56% of the men in LNG 0 (P < 0.05 for the combination groups vs. LNG 0), but there were no significant differences between the combination regimens (P = NS). All four groups gained significant weight compared with their baselines, although the gain tended to be greater as the dosage of LNG increased (2.0+/-0.9, 2.9+/-1.1, 3.6+/-1.0, and 5.4+/-1.0 kg gained, compared with baseline in the LNG 0, 125, 250, and 500 groups respectively; P < 0.05 compared with baseline). Serum levels of HDL cholesterol decreased in all of the groups, but the effect was larger as the dosage of LNG increased (4+/-4% vs. 13+/-4%, 20+/-3%, and 22+/-4% decrease in HDL levels from baseline in the LNG 0, LNG 125, LNG 250, and LNG 500 groups respectively; P = 0.06 for LNG 125 compared with LNG 0, and P < 0.05 for LNG 250 and LNG 500 compared with LNG 0). We conclude that 1) the combination of physiologic exogenous T enanthate and LNG suppresses spermatogenesis more effectively than T enanthate alone and that 2) the combination regimen of T enanthate plus lower dosage LNG suppresses sperm production comparably to T enanthate plus higher dosage LNG, while causing less weight gain and HDL cholesterol suppression. A combination regimen of physiologic testosterone plus a low dosage of levonorgestrel offers great promise as a safe and effective male contraceptive regimen.


Assuntos
Anticoncepcionais Masculinos/administração & dosagem , Gonadotropinas Hipofisárias/sangue , Levanogestrel/administração & dosagem , Espermatogênese/efeitos dos fármacos , Testosterona/análogos & derivados , Acne Vulgar/induzido quimicamente , Adulto , Apolipoproteína A-I/sangue , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Anticoncepcionais Masculinos/efeitos adversos , Anticoncepcionais Masculinos/sangue , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Ginecomastia/induzido quimicamente , Humanos , Levanogestrel/efeitos adversos , Levanogestrel/sangue , Masculino , Método Simples-Cego , Contagem de Espermatozoides/efeitos dos fármacos , Testosterona/administração & dosagem , Testosterona/efeitos adversos , Testosterona/sangue
18.
J Gen Intern Med ; 13(9): 627-39, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9754520

RESUMO

OBJECTIVE: To summarize for clinicians recent epidemiologic evidence regarding medical risks of alcohol use for women. METHODS: MEDLINE and PsychINFO, 1990 through 1996, were searched using key words "women" or "woman," and "alcohol." MEDLINE was also searched for other specific topics and authors from 1980 through 1996. Data were extracted and reviewed regarding levels of alcohol consumption associated with mortality, cardiovascular disease, alcohol-related liver disease, injury, osteoporosis, neurologic symptoms, psychiatric comorbidity, fetal alcohol syndrome, spontaneous abortion, infertility, menstrual symptoms, breast cancer, and gynecologic malignancies. Gender-specific data from cohort studies of general population or large clinical samples are primarily reviewed. MAIN RESULTS: Women develop many alcohol-related medical problems at lower levels of consumption than men, probably reflecting women's lower total body water, gender differences in alcohol metabolism, and effects of alcohol on postmenopausal estrogen levels. Mortality and breast cancer are increased in women who report drinking more than two drinks daily. Higher levels of alcohol consumption by women are associated with increased menstrual symptoms, hypertension, and stroke. Women who drink heavily also appear to have increased infertility and spontaneous abortion. Adverse fetal effects occur after variable amounts of alcohol consumption, making any alcohol use during pregnancy potentially harmful. CONCLUSIONS: In general, advising nonpregnant women who drink alcohol to have fewer than two drinks daily is strongly supported by the epidemiologic literature, although specific recommendations for a particular woman should depend on her medical history and risk factors.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Doenças Cardiovasculares/etiologia , Feminino , Transtornos do Espectro Alcoólico Fetal/etiologia , Neoplasias dos Genitais Femininos/etiologia , Humanos , Hepatopatias/etiologia , Masculino , Osteoporose Pós-Menopausa/fisiopatologia , Gravidez , Complicações na Gravidez/etiologia , Assunção de Riscos , Caracteres Sexuais
19.
J Clin Endocrinol Metab ; 83(10): 3527-33, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9768659

RESUMO

GnRH antagonists plus testosterone (T) suppress LH and FSH levels and inhibit spermatogenesis to azoospermia or severe oligozoospermia. High-dose T treatment alone has been shown to be an effective male contraceptive (contraceptive efficacy rate of 1.4 per 100 person yr). Combined GnRH antagonist and T induces azoospermia more rapidly and at a higher incidence than T alone; this combination has therefore been proposed as a prototype male contraceptive. However, because GnRH antagonists are expensive to synthesize and difficult to deliver, it would be desirable to rapidly suppress sperm counts to low levels with GnRH antagonist plus T and maintain azoospermia or severe oligozoospermia with T alone. In this study, 15 healthy men (age 21-41 yr) with normal semen analyses were treated with T enanthate (TE) 100 mg im/week plus 10 mg Nal-Glu GnRH antagonist sc daily for 12 weeks to induce azoospermia or severe oligozoospermia. At 12-16 weeks, 10 of 15 subjects had zero sperm counts, and 14 of 15 had sperm counts less than 3 x 10(6)/mL. The 14 who were suppressed on combined treatment were maintained on TE alone (100 mg/week im) for an additional 20 weeks. Thirteen of 14 subjects in the TE alone phase had sperm counts maintained at less than 3 x 10(6)/mL for 20 weeks. Ten remained persistently azoospermic or had sperm concentration of 0.1 x 10(6)/mL once during maintenance. Mean LH and FSH levels in the subjects were suppressed to 0.4+/-0.2 IU/L and 0.5+/-0.2 IU/L in the induction phase, which was maintained in the maintenance phase. The 1 subject who failed to suppress sperm counts during induction had serum LH and FSH reduced to 0.3 and 0.5 IU/L, respectively. The subject who failed to maintenance had LH and FSH suppressed to 1.0 and 0.2 IU/L, respectively, during the induction phase but these rose to 1.6 and 2.1 IU/L, respectively, during maintenance. Failure to suppress or maintain low sperm counts may be related to incomplete suppression of serum LH and FSH levels. We conclude that sperm counts suppressed with GnRH antagonist plus T can be maintained with relatively low dose TE treatment alone. This concept should be explored further in the development of effective, safe, and affordable hormonal male contraceptives.


Assuntos
Anticoncepcionais Masculinos/farmacologia , Dipeptídeos/farmacologia , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Antagonistas de Hormônios/farmacologia , Espermatogênese/efeitos dos fármacos , Testosterona/análogos & derivados , Adulto , Anticoncepcionais Masculinos/efeitos adversos , Dipeptídeos/efeitos adversos , Hormônio Foliculoestimulante/sangue , Antagonistas de Hormônios/efeitos adversos , Humanos , Libido/efeitos dos fármacos , Hormônio Luteinizante/sangue , Masculino , Comportamento Sexual/efeitos dos fármacos , Testosterona/efeitos adversos , Testosterona/sangue , Testosterona/farmacologia
20.
Fertil Steril ; 69(1): 89-95, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9457940

RESUMO

OBJECTIVE: To determine whether immature spermatids increase in semen in response to hormonal contraceptive treatments. Such a finding would support the existence of a defect in spermiogenesis, which in turn may explain the reported variability in sperm output. DESIGN: Semen smears were obtained from healthy men undergoing randomized control trials of T plus progestin contraceptive treatments. PATIENT(S): Healthy men (21-49 years) with normal semen analyses received T (50-100 mg IM weekly) in combination with either desogestrel (150-300 microg daily, n = 5) or levonorgestrel (125-250 microg daily, n = 10) for 24 weeks. Semen smears were made during spermatogenic suppression and recovery. Nine control subjects were also assessed. MAIN OUTCOME MEASURE(S): Semen analyses were performed using World Health Organization criteria. Immature spermatids and white blood cells in semen were identified by immunostaining with monoclonal antibodies to the human intra-acrosomal antigen SP-10 and the ubiquitous white cell CD-45 antigen, respectively. RESULT(S): In a total of 14 normal ejaculates (9 control and 5 pretreatment) 74+/-14 million/mL sperm (mean+/-SEM) were seen together with a few immature spermatids (0.69+/-0.20 million/mL). During contraceptive treatments, spermatid number decreased in parallel with the sperm concentration and spermatids disappeared in most subjects. No significant changes were seen in either leukocyte or immunonegative round cell concentration (0.41+/-0.25 and 0.25+/-0.09 million/mL in controls, respectively) in response to treatments. CONCLUSION(S): Spermatid sloughing, as assessed by the ejaculation of immature spermatids, is not a feature of T-induced spermatogenic regression in men; rather, the decline in both mature and immature germ cells in the ejaculate probably results from a decline in the number of precursor cells, ultimately resulting in severe oligo- or azoospermia. Detailed studies on the sites of spermatogenic interruption are required to understand the variability in responses seen after contraceptive therapies in men.


Assuntos
Androgênios/farmacologia , Anticoncepcionais Masculinos/farmacologia , Sêmen/efeitos dos fármacos , Espermátides/efeitos dos fármacos , Adulto , Senescência Celular/efeitos dos fármacos , Senescência Celular/fisiologia , Anticoncepcionais Orais Sintéticos/farmacologia , Desogestrel/farmacologia , Combinação de Medicamentos , Humanos , Levanogestrel/farmacologia , Masculino , Pessoa de Meia-Idade , Sêmen/fisiologia , Contagem de Espermatozoides/efeitos dos fármacos , Espermátides/fisiologia , Testosterona/farmacologia
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