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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.
Andrology ; 5(2): 278-285, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27907978

RESUMO

Dimethandrolone (DMA, 7α,11ß-dimethyl-19-nortestosterone) has both androgenic and progestational activities, ideal properties for a male hormonal contraceptive. In vivo, dimethandrolone undecanoate (DMAU) is hydrolyzed to DMA. We showed previously that single oral doses of DMAU powder in capsule taken with food are well tolerated and effective at suppressing both LH and testosterone (T), but absorption was low. We compared the pharmacokinetics and pharmacodynamics of two new formulations of DMAU, in castor oil and in self-emulsifying drug delivery systems (SEDDS), with the previously tested powder formulation. DMAU was dosed orally in healthy adult male volunteers at two academic medical centers. For each formulation tested in this double-blind, placebo-controlled study, 10 men received single, escalating, oral doses of DMAU (100, 200, and 400 mg) and two subjects received placebo. All doses were evaluated for both fasting and with a high fat meal. All three formulations were well tolerated without clinically significant changes in vital signs, blood counts, or serum chemistries. For all formulations, DMA and DMAU showed higher maximum (p < 0.007) and average concentrations (p < 0.002) at the 400 mg dose, compared with the 200 mg dose. The powder formulation resulted in a lower conversion of DMAU to DMA (p = 0.027) compared with both castor oil and SEDDS formulations. DMAU in SEDDS given fasting resulted in higher serum DMA and DMAU concentrations compared to the other two formulations. Serum LH and sex hormone concentrations were suppressed by all formulations of 200 and 400 mg DMAU when administered with food, but only the SEDDS formulation was effectively suppressed serum T when given fasting. We conclude that while all three formulations of oral DMAU are effective and well tolerated when administered with food, DMAU in oil and SEDDS increased conversion to DMA, and SEDDS may have some effectiveness when given fasting. These properties might be advantageous for the application of DMAU as a male contraceptive.


Assuntos
Anticoncepcionais Masculinos/farmacologia , Nandrolona/análogos & derivados , Administração Oral , Adulto , Anticoncepcionais Masculinos/efeitos adversos , Anticoncepcionais Masculinos/farmacocinética , Di-Hidrotestosterona/sangue , Método Duplo-Cego , Sistemas de Liberação de Medicamentos , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Nandrolona/efeitos adversos , Nandrolona/farmacocinética , Nandrolona/farmacologia , Testosterona/sangue
4.
Andrology ; 3(3): 582-589, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25891800

RESUMO

Humanin (HN) has cytoprotective action on male germ cells after testicular stress induced by heat and hormonal deprivation. To examine whether HN has protective effects on chemotherapy-induced male germ cell apoptosis, we treated four groups of adult rats with (i) vehicle (control), (ii) HN, (iii) cyclophosphamide (CP); or (iv) HN+CP. To investigate whether the protective effects of HN on germ cells require the presence of Leydig cells, another four groups of rats were pre-treated with ethane dimethanesulfonate (EDS), a Leydig cell toxicant, to eliminate Leydig cells. After 3 days, when Leydig cells were depleted by EDS, we administered: (i) vehicle, (ii) HN, (iii) CP; or (iv) HN+CP to rats. All rats were killed 12 h after the injection of HN and/or CP. Germ cell apoptosis was detected by TUNEL assay and quantified by numerical count. Compared with control and HN (alone), CP significantly increased germ cell apoptosis; HN +CP significantly reduced CP-induced apoptosis at early (I-VI) and late stages (IX-XIV) but not at middle stages (VII-VIII) of the seminiferous epithelial cycle. Pre-treatment with EDS markedly suppressed serum and intratesticular testosterone (T) levels, and significantly increased germ cell apoptosis at the middle (VII-VIII) stages. CP did not further increase germ cell apoptosis in the EDS-pre-treated rats. HN significantly attenuated germ cell apoptosis at the middle stages in EDS pre-treated rats. To investigate whether HN has any direct effects on Leydig cell function, adult Leydig cells were isolated and treated with ketoconazole (KTZ) to block testosterone synthesis. HN was not effective in preventing the reduction of T production by KTZ in vitro. We conclude that HN decreases CP and/or EDS-induced germ cell apoptosis in a stage-specific fashion. HN acts directly on germ cells to protect against EDS-induced apoptosis in the absence of Leydig cells and intratesticular testosterone levels are very low.


Assuntos
Proteínas Reguladoras de Apoptose/farmacologia , Apoptose/efeitos dos fármacos , Ciclofosfamida/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Células Intersticiais do Testículo/efeitos dos fármacos , Animais , Cetoconazol/farmacologia , Masculino , Mesilatos/farmacologia , Ratos , Ratos Sprague-Dawley , Espermatozoides/patologia , Testosterona/biossíntese , Testosterona/sangue , Testosterona/metabolismo
5.
Endocrinology ; 155(2): 417-28, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24280056

RESUMO

Nonalcoholic fatty liver disease is common in developed countries and is associated with obesity, metabolic syndrome, and type 2 diabetes. T deficiency is a risk factor for developing these metabolic deficiencies, but its role in hepatic steatosis has not been well studied. We investigated the effects of T on the pathogenesis of hepatic steatosis in rats fed a high-fat diet (HFD). Adult male rats were randomly placed into four groups and treated for 15 weeks: intact rats on regular chow diet (RCD), intact rats on liquid HFD (I+HFD), castrated rats on HFD (C+HFD), and castrated rats with T replacement on HFD (C+HFD+T). Fat contributed 71% energy to the HFD but only 16% of energy to the RCD. Serum T level was undetectable in castrated rats, and T replacement led to 2-fold higher mean serum T levels than in intact rats. C+HFD rats gained less weight but had higher percentage body fat than C+HFD+T. Severe micro- and macrovesicular fat accumulated in hepatocytes with multiple inflammatory foci in the livers of C+HFD. I+HFD and C+HFD+T hepatocytes demonstrated only mild to moderate microvesicular steatosis. T replacement attenuated HFD-induced hepatocyte apoptosis in castrated rats. Serum glucose and insulin levels were not increased with HFD in any group. Immunoblots showed that insulin-regulated proteins were not changed in any group. This study demonstrates that T deficiency may contribute to the severity of hepatic steatosis and T may play a protective role in hepatic steatosis and nonalcoholic fatty liver disease development without insulin resistance.


Assuntos
Fígado Gorduroso/tratamento farmacológico , Terapia de Reposição Hormonal , Fígado/efeitos dos fármacos , Testosterona/uso terapêutico , Adiponectina/sangue , Animais , Apoptose/efeitos dos fármacos , Composição Corporal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Castração , Ingestão de Alimentos/efeitos dos fármacos , Ácidos Graxos não Esterificados/sangue , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Insulina/sangue , Leptina/sangue , Fígado/metabolismo , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
6.
Andrology ; 1(6): 899-905, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24123845

RESUMO

Development of a male hormonal contraceptive has been challenging ascribable to the failure to adequately suppress spermatogenesis in 5-10% of men. Methods to identify incomplete suppressors early in treatment might identify men most responsive to male hormonal contraceptives. We hypothesized that serum hormone and gonadotropin concentrations after 4 weeks of transdermal treatment with testosterone and Nestorone in a contraceptive trial would be associated with suppression of sperm concentrations to <1 million/mL after 24 weeks. Indeed, luteinizing hormone or follicle-stimulating hormone concentrations greater than 1 IU/L after 4 weeks of transdermal testosterone/nestorone treatment were 97% sensitive for predicting failure to suppress spermatogenesis after 24 weeks of treatment. Serum nestorone concentrations were significantly associated with suppression, but serum testosterone concentrations were not. Early suppression of gonadotropins is associated with, but does not ensure, adequate suppression of spermatogenesis. This information may allow for rapid identification of non-responders in male hormonal contraceptive trials.


Assuntos
Norprogesteronas/farmacologia , Administração Cutânea , Adolescente , Adulto , Anticoncepcionais Masculinos/farmacologia , Hormônio Foliculoestimulante/sangue , Géis , Humanos , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Norprogesteronas/administração & dosagem , Norprogesteronas/sangue , Espermatogênese/efeitos dos fármacos , Testosterona/administração & dosagem , Testosterona/sangue , Testosterona/farmacologia
7.
Int J Androl ; 33(4): 581-7, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19622086

RESUMO

XXY mouse has been characterized as an experimental model for men with Klinefelter's syndrome (XXY male phenotype). To test whether donor XY germ cells could proliferate and differentiate in the XXY testicular environment, donor testicular cells from adult (2-3 months old) and immature (10 days old) XY green fluorescence protein (GFP) transgenic mice were transplanted into the seminiferous tubules of adult (4-7 months old) and young (6 weeks old) XXY recipient mice respectively. Twelve weeks after transplantation, GFP positive spermatogonia were found in 21.74% (five out of 23) of adult XXY recipients who received adult donor cells. The GFP positive segments of seminiferous tubules were observed in 44.44% (four out of nine) young XXY recipients who received donor cells from 10 days old GFP mice. We found using immunohistochemistry and cell morphology that donor-derived GFP positive germ cells were spermatogonia, spermatocytes, round spermatids and spermatozoa in some of the seminiferous tubules of young XXY recipient mice. The results demonstrated that the donor XY germ cells were able to qualitatively complete spermatogenesis in some of the seminiferous tubules of XXY mice.


Assuntos
Células Germinativas/transplante , Síndrome de Klinefelter/genética , Testículo/citologia , Animais , Diferenciação Celular , Proliferação de Células , Proteínas de Fluorescência Verde/genética , Masculino , Camundongos , Camundongos Transgênicos , Espermatozoides/citologia
8.
Int J Impot Res ; 21(2): 89-98, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18843273

RESUMO

Obesity is an important risk factor for many common diseases including cardiovascular disease (CVD), type 2 diabetes, cancer and erectile dysfunction (ED). Adipose tissues produce a number of adipokines and cytokines, which affect endothelial and metabolic function resulting in insulin resistance and the metabolic syndrome (risks factors for CVD). Both ED and metabolic syndrome improve with a reduction in body mass index (BMI). The relationships among obesity, metabolic syndrome, ED, sex hormone-binding globulin (SHBG) and serum total and free testosterone levels are complex and often confusing to the physician. It is known that BMI is inversely proportional to serum total testosterone concentrations; low serum SHBG levels in obesity contribute to the low serum total testosterone. Recent studies show that BMI is also inversely proportional to free testosterone concentration. The characteristic low serum testosterone concentrations observed in obese men are also present in men with the metabolic syndrome and type 2 diabetes mellitus. A small proportion of men with ED have hypogonadism; however, the proportion increases if these men are obese with manifestations of the metabolic syndrome or type 2 diabetes mellitus. ED is a common symptom in patients with type 2 diabetes who also have low testosterone levels. This review describes the relationships between low serum testosterone concentrations and ED in obese patients and those with metabolic syndrome and type 2 diabetes mellitus.


Assuntos
Disfunção Erétil/complicações , Obesidade/complicações , Testosterona/sangue , Testosterona/deficiência , Tecido Adiposo/patologia , Androgênios/uso terapêutico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Disfunção Erétil/sangue , Disfunção Erétil/tratamento farmacológico , Disfunção Erétil/patologia , Humanos , Masculino , Síndrome Metabólica/sangue , Síndrome Metabólica/patologia , Obesidade/sangue , Obesidade/tratamento farmacológico , Obesidade/patologia
9.
J Clin Endocrinol Metab ; 91(4): 1423-7, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16403821

RESUMO

CONTEXT: Adults with Klinefelter's syndrome (KS) are known to present disturbances of language skills and delayed learning abilities. OBJECTIVES: The aim of this study was to assess brain morphometry in KS and to correlate eventual volumetric changes with performance on neuropsychological tests. PATIENTS: Patients included 18 KS adults and 20 age-matched controls. METHODS: All participants underwent prospectively double-spin-echo brain magnetic resonance imaging and neuropsychological testing of verbal and nonverbal domains. On the axial stack of magnetic resonance imaging slices, regional brain volumes were measured either by automated segmentation (full brain, total cerebrospinal fluid, and ventricular volume) or manual drawing with help of a neuroanatomy atlas (frontal, temporal, and parietal lobes, gray matter component of the lobes, cerebellar hemispheres, and hippocampal complexes). RESULTS: KS patients performed significantly lower than controls on language-related tasks exploring verbal processing speed and verbal executive function. They were diagnosed with significant enlargement of ventricular volume and bilateral reduction of cerebellar hemispheres. Furthermore, after separation of participants according to handedness and after correction of regional brain volumes for atrophy, a significant reduction of left temporal lobe volume was found in KS compared with controls. Ventricular volume was inversely correlated with cognitive function, whereas left temporal lobe volume was positively correlated with language-related tasks. CONCLUSION: This study hypothesizes that supernumerary X-chromosome and/or congenital hypogonadism provoke structural alterations in the subcortical pathways involved in language processing, thus providing a neurobiological substrate for cognitive deficits in KS.


Assuntos
Encéfalo/patologia , Transtornos Cognitivos/patologia , Transtornos Cognitivos/psicologia , Síndrome de Klinefelter/patologia , Síndrome de Klinefelter/psicologia , Adolescente , Adulto , Ventrículos Cerebrais/patologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Testosterona/farmacologia
10.
J Endocrinol Invest ; 28(3 Suppl): 109-11, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16042368

RESUMO

Until more data on the efficacy and risks of testosterone (T) treatment of hypogonadal older men become available, the use of T substitution in men in this age group should be carefully considered and benefits vs risks should be discussed with the patient. Generally symptoms of hypogonadism together with low serum T levels are considered indications for treatment. For aging men, short acting preparations may be preferred and levels of serum T are maintained with in the mid adult range. Careful assessment for improvement of symptoms is the essential goal of treatment. Monitoring for manifestations of prostate disease, erythrocytosis and other adverse events of androgen treatment is critical in the management of older men with androgen replacement therapy.


Assuntos
Terapia de Reposição Hormonal , Testosterona/administração & dosagem , Idoso , Envelhecimento , Contraindicações , Humanos , Hipogonadismo/tratamento farmacológico , Masculino , Testosterona/efeitos adversos , Testosterona/deficiência , Resultado do Tratamento
11.
J Endocrinol Invest ; 28(3 Suppl): 112-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16042369

RESUMO

Transdermal testosterone (T) gels have proven to be an efficacious means of delivering T to hypogonadal men. Patches, gels and creams have been used in T transdermal formulations. Patches suffered from problems either with adherence or skin irritability while gels have a potential problem of transferability from patients to partner or other family member. At present, gels have been well received by clinicians and users. There is no evidence that transdermal preparations are not suitable for treatment of older hypogonadal men; the rapid off time of both patches and gels may argue allow that transdermal preparations may be a preferential treatment modality for older men with a potential higher risk of developing androgen-responsive prostate cancer.


Assuntos
Envelhecimento , Androgênios/administração & dosagem , Hipogonadismo/tratamento farmacológico , Administração Cutânea , Idoso , Androgênios/efeitos adversos , Géis , Humanos , Masculino , Neoplasias da Próstata/induzido quimicamente , Escroto/efeitos dos fármacos , Testosterona/sangue
12.
Aging Male ; 6(3): 207-11, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14628501

RESUMO

Transdermal testosterone gels represent an effective alternative to injectable testosterone preparations. Short-term (6 months) data demonstrated positive effects on muscle, bone, fat, libido and mood. This report provides a preliminary analysis of longer-term treatment with a testosterone gel (AndroGel or Testogel) in a group of men aged 19-67 years of age. The positive effects of testosterone treatment on all of the above parameters persisted in this 3-year follow-up. The benefits occurred independent of age (equally in the older and younger subjects). The positive effects of transdermal testosterone gel on bone mineral density previously identified at 6 months of treatment, continued with time. The positive effects on bone mineral density were greater in the spine than the hip. There were minimal effects on lipid levels. Levels of prostate-specific antigen (PSA) increased with testosterone treatment but, in general, remained in the normal range. Three subjects (1.8%) were shown to have elevated PSA and biopsy-proven prostate cancer. It was not possible to determine if this incidence is above the background rate. Monitoring for prostate disease through PSA measurements and digital rectal examination is recommended for hypogonadal men in the older age groups when treated with testosterone.


Assuntos
Androgênios/administração & dosagem , Géis/administração & dosagem , Terapia de Reposição Hormonal/métodos , Hipogonadismo/tratamento farmacológico , Testosterona/administração & dosagem , Adulto , Afeto , Idoso , Androgênios/uso terapêutico , Composição Corporal/efeitos dos fármacos , Densidade Óssea , Colesterol/sangue , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Policitemia , Antígeno Prostático Específico , Sexualidade , Testosterona/uso terapêutico , Resultado do Tratamento
13.
J Clin Endocrinol Metab ; 87(8): 3562-72, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12161475

RESUMO

Recent studies demonstrate that combinations of androgens and progestagens are highly effective in the suppression of spermatogenesis in normal volunteers. To test whether progestagen and androgen delivery systems designed to produce steady serum levels will be as effective as other androgen plus progestagen combinations, we compared Norplant II and testosterone (T) transdermal patch to T patch alone on the suppression of spermatogenesis in normal men. Thirty-nine healthy male volunteers (age, 20-45 yr) were randomly assigned to one of two groups. Group 1 (n = 19) received two transdermal T patches daily (Testoderm TTS, each patch designed to deliver about 5 mg/d T) alone, and group 2 (n = 20) received combined Norplant II [Jadelle, four capsules delivering approximately 160 microg/d levonorgestrel (LNG)] plus T patch. Neither of these regimens were very effective, with suppression of spermatogenesis to severe oligozoospermia occurring in less than 60% of subjects. We then expanded the study to include two more groups to determine whether T patch or Norplant II was the main factor causing the inadequate suppression of spermatogenesis. Another 29 subjects were randomized to one of two groups. Group 3 (n = 15) received oral LNG (125 microg/d) plus T patch, and group 4 (n = 14) received Norplant II plus T enanthate (TE) injection (100 mg/wk i.m.). After a pretreatment phase of 4 wk, all subjects received treatment for 24 wk, followed by a recovery period of 12-24 wk. Steady-state serum LNG levels (800-1200 pmol/liter) were achieved from wk 3-24 after Norplant II insertion and decreased rapidly after the removal of the implants at wk 24. Trough serum LNG levels after oral LNG administration were at a comparable range (940-1300 pmol/liter). Azoospermia was achieved in 24%, 35%, 33%, and 93%, and severe oligozoospermia (<1 x 10(6)/ml) developed in 24%, 60%, 42%, and 100% of the subjects in groups 1, 2, 3, and 4, respectively, during treatment phase. All subjects in the Norplant II plus TE groups had persistent sperm concentrations less than 3 x 10(6)/ml from wk 12 until the end of treatment. Concomitant with the marked suppression of spermatogenesis in the Norplant II plus TE group, serum FSH and LH levels were most decreased in this group compared with all other groups. In the T patch-only group, serum SHBG was not suppressed, and total serum T was higher than baseline levels. In the other three groups administered progestagens, serum SHBGs were significantly suppressed, and serum total T remained similar to baseline levels. Serum free T levels were not changed in any group. Except for a suppression of serum high-density lipoprotein cholesterol, there was no significant change in weight, hematocrit, clinical chemistry, or prostate-specific antigen levels in any of the treatment groups. Although more efficacious than T patch alone, Norplant II or oral LNG plus T patch was not as effective in suppressing spermatogenesis to severe oligo- or azoospermia as in previous reports using oral LNG plus TE. This relative lesser efficacy occurred despite the achievement of serum LNG levels by Norplant II that were equivalent to those reported after administration of oral LNG. Substituting the transdermal T delivery system with TE injections resulted in very effective suppression of sperm output. The difference in spermatogenesis suppression of these combined regimens is likely due to less T delivered by the transdermal patch compared with the TE weekly injections. We conclude that Norplant II implants plus TE 100 mg/wk were very efficient in suppressing spermatogenesis to a level acceptable for contraceptive efficacy. This study demonstrates that the dose or route of administration of androgens is critical for sperm suppression in combined androgen-progestagen regimens for hormonal male contraception.


Assuntos
Anticoncepcionais Masculinos/administração & dosagem , Hormônios Esteroides Gonadais/administração & dosagem , Levanogestrel/administração & dosagem , Testosterona/administração & dosagem , Administração Cutânea , Adolescente , Adulto , Peso Corporal , Coito , Anticoncepção/métodos , Anticoncepcionais Masculinos/efeitos adversos , Anticoncepcionais Masculinos/sangue , Implantes de Medicamento , Hormônio Foliculoestimulante/sangue , Hormônios Esteroides Gonadais/sangue , Humanos , Levanogestrel/efeitos adversos , Levanogestrel/sangue , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Globulina de Ligação a Hormônio Sexual/metabolismo , Espermatogênese/efeitos dos fármacos , Testículo/anatomia & histologia , Testículo/efeitos dos fármacos , Testosterona/sangue
14.
J Androl ; 22(6): 981-91, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11700863

RESUMO

To explore the functional role of Bcl-2 in germ cell development, transgenic mice carrying 6 kilobases of the inhibin-alpha promoter were generated to express human bcl-2 gene product in the gonads. Although female transgenic mice demonstrated decreased follicle apoptosis, enhanced folliculogenesis, and increased germ cell tumorigenesis, the adult males exhibited variable impairment of spermatogenesis. The degree of damage ranged from tubules with intraepithelial vacuoles of varying sizes to near atrophied tubules consisting of Sertoli cells and a few spermatogonia. Although there was no significant change in body weight, an approximately 34% decrease in testicular weights was noted in transgenic animals compared with wild-type mice. Gamete maturation, assessed by determining the percentage of tubules with advanced (steps 13-16) spermatids, was decreased to 44.4% of the values measured in the wild-type animals. The incidence of germ cell apoptosis increased 3.8-fold in the transgenic animals and was associated with a marked loss of germ cells. Electron microscopy of the testes further revealed large vacuoles in the Sertoli cell cytoplasm and dilations of the intracellular spaces between adjacent Sertoli cells, spermatid malformations, and increased germ cell apoptosis in the transgenic animals. There was no evidence of Sertoli cell death either by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay or electron microscopy. Leydig cell ultrastructure, cell size and numbers, and plasma levels of testosterone were not different between normal and the transgenic animals. Collectively, these results support the critical role of Bcl-2 in male germ cell development and are consistent with the gender-specific role of the Bcl-2 family members in reproduction.


Assuntos
Regulação da Expressão Gênica , Genes bcl-2 , Camundongos Transgênicos , Espermatogênese/genética , Testículo/fisiologia , Animais , Apoptose/genética , Peso Corporal , Feminino , Hormônio Foliculoestimulante/sangue , Masculino , Camundongos , Tamanho do Órgão , Folículo Ovariano/citologia , Células de Sertoli/citologia , Espermatozoides/anormalidades , Testículo/anatomia & histologia , Testículo/ultraestrutura , Testosterona/sangue , Vacúolos/ultraestrutura
15.
Neuroendocrinology ; 74(1): 1-11, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11435753

RESUMO

UNLABELLED: We have previously demonstrated that the inducible nitric oxide synthase (iNOS) protein and total NOS activity increase in the hypothalamus and other regions of the male rat brain during aging. We have now tested the hypothesis that increased iNOS results in excessive nitric oxide (NO) and peroxynitrite production, and leads to increased apoptosis in CNS cells, including the GnRH and oxytocin hypothalamic neurons involved in the control of male reproductive function. Young (3-month-old) and old (24-month-old) male Brown Norway rats (n = 6) were perfused with 4% formalin. Adjacent coronal paraffin-embedded sections (5 microm) of preoptic area (POA), supraoptic nucleus (SON), paraventricular nucleus (PVN), and arcuate nucleus (ARC) of the hypothalamus were immunostained with antibodies for iNOS, neuronal NOS (nNOS), and nitrotyrosine (a marker of peroxynitrite formation). The intensity of immunostaining was measured using a densitometric image analysis system. Apoptosis was determined by the TUNEL assay. Double immunofluorescence staining with confocal laser scanning microscopy was used for co-localization studies. A significant increase in the iNOS immunostaining measured as optical density (OD) was found in the old compared to the young animals (SON: 0.32 +/- 0.02 vs. 0.23 +/- 0.03, p < 0.05; PVN: 0.34 +/- 0.03 vs. 0.07 +/- 0.05, p < 0.001; POA: 0.18 +/- 0.02 vs. 0.01 +/- 0.02, p < 0.001). Aging did not affect nNOS expression. Nitrotyrosine was elevated in the hypothalamic regions of old compared to young rats (SON: 0.32 +/- 0.05 vs. 0.10 +/- 0.04, p < 0.05; PVN: 0.32 +/- 0.04 vs. 0.13 +/- 0.03, p < 0.01; POA: 0.72 +/- 0.06 vs. 0.03 +/- 0.003, p < 0.001). Increased nitrotyrosine was accompanied by an elevation of the apoptotic index in the old rats (SON: 11.01 +/- 3.33 vs. 0.57 +/- 0.50, p < 0.001; PVN: 3.08 +/- 1.12 vs. 0.42 +/- 0.32; POA: 6.60 +/- 1.93 vs. 0.18 +/- 0.17, p < 0.01; ARC: 0.001 +/- 0.0001 vs. 4.33 +/- 2.33). iNOS staining co-localized with GnRH and oxytocin staining. IN CONCLUSION: The aging-related iNOS increased expression in the hypothalamus of the male rat affects regions known to control the synthesis and release of GnRH (POA, ARC) and oxytocin (PVN, SON), and the factors regulating penile erection (POA, and PVN). These observations suggest that iNOS may play a role in the reduction in GnRH and oxytocin neuronal secretion resulting in reproductive dysfunctions such as lowered serum testosterone, hypospermatogenesis, and diminished copulatory function in the aging male animal.


Assuntos
Envelhecimento/fisiologia , Hipotálamo/química , Neurônios/química , Óxido Nítrico Sintase/análise , Reprodução , Tirosina/análogos & derivados , Animais , Apoptose , Biomarcadores , Hormônio Liberador de Gonadotropina/análise , Hipotálamo/citologia , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Microscopia de Fluorescência , Óxido Nítrico , Óxido Nítrico Sintase Tipo I , Óxido Nítrico Sintase Tipo II , Ocitocina/análise , Ratos , Ratos Endogâmicos BN , Tirosina/análise
16.
Clin Endocrinol (Oxf) ; 54(6): 739-50, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11422108

RESUMO

OBJECTIVE: Androgen replacement has been reported to increase bone mineral density (BMD) in hypogonadal men. We studied the effects of 6 months of treatment with a new transdermal testosterone (T) gel preparation on bone turnover markers and BMD. DESIGN: This was a prospective, randomized, multicentre, parallel clinical trial where 227 hypogonadal men, mean age 51 years (range: 19-68 years) were studied in 16 academic and research institutions in the USA. Subjects were randomized to apply 1% T gel containing 50 or 100 mg T (delivering approximately 5-10 mg T/day) or two T patches (delivering 5 mg T/day) transdermally for 90 days. At day 91, depending on the serum T concentration, the T gel dose was adjusted upward or downward to 75 mg T/day until day 180. No dose adjustment occurred in the T patch group. MEASUREMENTS: Serum T, free T and oestradiol, bone turnover markers and BMD were measured on days 0, 30, 90 and 180 before and after treatment. RESULTS: Application of T gel 100 mg/day resulted in serum T concentrations 1.4 and 1.9-fold higher than in the T gel 50 mg/day and the T patch groups, respectively. Proportional increases occurred in serum oestradiol. Urine N-telopeptide/creatinine ratio, a marker for bone resorption, decreased significantly (P = 0.0019) only in the T gel 100 mg/day group. Serum bone osteoblastic activity markers (osteocalcin, procollagen and skeletal alkaline phosphatase) increased significantly during the first 90 days of treatment without intergroup differences but declined to baseline thereafter. BMD increased significantly both in the hip (+1.1 +/- 0.3%) and spine (+2.2 +/- 0.5%) only in the T gel 100 mg/day group (P = 0.0001). CONCLUSIONS: Transdermal testosterone gel application for 6 months decreased bone resorption markers and increased osteoblastic activity markers for a short period, which resulted in a small but significant increase in BMD. Ongoing long-term studies should answer whether the observed increases in BMD are sustained or continue to be dependent on the dose of testosterone administered.


Assuntos
Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Hipogonadismo/tratamento farmacológico , Testosterona/uso terapêutico , Administração Cutânea , Adulto , Idoso , Fosfatase Alcalina/sangue , Análise de Variância , Biomarcadores/sangue , Biomarcadores/urina , Cálcio/sangue , Colágeno/urina , Colágeno Tipo I , Creatinina/urina , Esquema de Medicação , Estradiol/sangue , Géis , Humanos , Masculino , Pessoa de Meia-Idade , Osteocalcina/sangue , Peptídeos/urina , Fósforo/sangue , Pró-Colágeno/sangue , Estudos Prospectivos , Testosterona/sangue
17.
Endocr Rev ; 22(3): 342-88, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11399748

RESUMO

This review is designed to help the reproductive endocrinologist integrate his or her professional activity with those of other disciplines including urology, radiology, neurology, and psychology in order to successfully manage all of the inseparable aspects of male sexual and reproductive functioning. Significant advances in the field of male sexual physiology and pathophysiology and new methods of investigation and treatment of male sexual disorders are outlined. The review synthesizes available data on the following: norms of sexual organs, aging and sexuality, role of central and peripheral neurochemicals in each stage of the sexual cycle, role of corporeal smooth muscles in the hemodynamic control of erection and detumescence, influence of psychological factors, drugs, and disease on all aspects of sexual functioning, and use of nocturnal penile tumescence monitoring, imaging investigations, and neurophysiologic studies in the diagnostic workup of males with sexual dysfunction. Clinical algorithms are presented where appropriate. Extensive discussions on newly developed strategies in psychological and behavioral counseling, drug therapy, tissue engineering, nonsurgical devices, and surgical treatments for all forms of sexual disorders are also provided. Lastly, the effect of sexual dysfunction and its treatment on quality of life in affected men is addressed, along with recommendations for future research endeavors.


Assuntos
Sexo , Disfunções Sexuais Fisiológicas/diagnóstico , Disfunções Sexuais Fisiológicas/terapia , Humanos , Masculino , Pênis/anatomia & histologia , Pênis/fisiologia , Pênis/fisiopatologia , Disfunções Sexuais Fisiológicas/fisiopatologia
18.
J Int Neuropsychol Soc ; 7(4): 446-56, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11396547

RESUMO

Children and adolescents with Klinefelter syndrome (XXY) have been reported to show deficits in language processing including VIQ < PIQ and a learning disability in reading and spelling. However, whether this is characteristic of adults with Klinefelter syndrome has not been established. Thirty-five men with Klinefelter syndrome, aged 16 to 61, and 22 controls were evaluated with a comprehensive neuropsychological battery. The Klinefelter patients scored significantly below controls in language skills, verbal processing speed, verbal and nonverbal executive abilities, and motor dexterity. Within the Klinefelter sample, three cognitive subgroups were identified: VIQ 7 or more points below PIQ (n = 10), VIQ within 6 points of PIQ (n = 12), and PIQ 7 or more points below VIQ (n = 12). The deficits detected in language, verbal processing speed, and verbal executive skills were found to be isolated to the VIQ < PIQ subgroup, while the abnormalities in motor dexterity and nonverbal executive skills were confined to the PIQ < VIQ subgroup. Older age was significantly correlated with increases in VIQ relative to PIQ in the patient group, which suggests the intriguing possibility that the PIQ < VIQ subgroup primarily emerges in young adulthood, perhaps in response to the reported hormonal abnormalities detected in Klinefelter syndrome patients during puberty.


Assuntos
Transtornos Cognitivos/diagnóstico , Síndrome de Klinefelter/genética , Adolescente , Adulto , Dislexia/diagnóstico , Lateralidade Funcional/fisiologia , Humanos , Transtornos da Linguagem/diagnóstico , Masculino , Pessoa de Meia-Idade , Transtornos das Habilidades Motoras/diagnóstico , Testes Neuropsicológicos , Tempo de Reação , Índice de Gravidade de Doença , Comportamento Verbal
19.
Endocrinology ; 142(4): 1461-70, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11250926

RESUMO

Klinefelter syndrome (47,XXY) is the most common sex chromosome aneuploidy in men. Thus, it is important to establish an experimental animal model to explore its underlying molecular mechanisms. Mice with a 41,XXY karyotype were produced by mating wild-type male mice with chimeric female mice carrying male embryonic stem cells. The objectives of the present study were to characterize the testicular phenotype of adult XXY mice and to examine the ontogeny of loss of germ cells in juvenile XXY mice. In the first experiment the testicular phenotypes of four adult XXY mice and four littermate controls (40,XY) were studied. XXY mice were identified by either Southern hybridization or karyotyping and were further confirmed by fluorescence in situ hybridization. The results showed that the testis weights of adult XXY mice (0.02 +/- 0.01 g) were dramatically decreased compared with those of the controls (0.11 +/- 0.01 g). Although no significant differences were apparent in plasma testosterone levels, the mean plasma LH and FSH levels were elevated in adult XXY mice compared with controls. The testicular histology of adult XXY mice showed small seminiferous tubules with varying degrees of intraepithelial vacuolization and a complete absence of germ cells. Hypertrophy and hyperplasia of Leydig cells were observed in the interstitium. Electron microscopic examination showed Sertoli cells containing scanty amounts of cytoplasm and irregular nuclei with prominent nucleoli. The junctional region between Sertoli cells appeared normal. In some tubules, nests of apparently degenerating Sertoli cells were found. In the second experiment the ontogeny of germ cell loss in juvenile XXY mice and their littermate controls was studied. Spermatogonia were found and appeared to be morphologically normal in juvenile XXY mice. Progressive loss of germ cells occurred within 10 days after birth. This resulted in the absence of germ cells in the adult XXY mice. We conclude that a progressive loss of germ cells occurring in early postnatal life results in the complete absence of germ cells in adult XXY mice. The XXY mouse provides an experimental model for its human XXY counterpart, Klinefelter syndrome.


Assuntos
Síndrome de Klinefelter/genética , Cromossomo X/genética , Cromossomo Y/genética , Animais , Southern Blotting , Peso Corporal/fisiologia , Modelos Animais de Doenças , Feminino , Fibroblastos/patologia , Fibroblastos/ultraestrutura , Células Germinativas/patologia , Células Germinativas/ultraestrutura , Cariotipagem , Síndrome de Klinefelter/patologia , Células Intersticiais do Testículo/patologia , Células Intersticiais do Testículo/ultraestrutura , Masculino , Camundongos , Microscopia Eletrônica , Tamanho do Órgão/fisiologia , Fenótipo , Gravidez , Cromossomo X/ultraestrutura , Cromossomo Y/ultraestrutura
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