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1.
Andrology ; 7(6): 878-887, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30969032

RESUMEN

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.


Asunto(s)
Agentes Anticonceptivos Hormonales/farmacología , Anticonceptivos Masculinos/farmacología , Gonadotropinas/sangre , Norprogesteronas/farmacología , Testosterona/farmacología , Adolescente , Adulto , Agentes Anticonceptivos Hormonales/farmacocinética , Anticonceptivos Masculinos/farmacocinética , Método Doble Ciego , Combinación de Medicamentos , Hormona Folículo Estimulante/sangre , Anticoncepción Hormonal , Humanos , Hormona Luteinizante/sangre , Masculino , Persona de Mediana Edad , Norprogesteronas/farmacocinética , Recuento de Espermatozoides , Espermatogénesis/efectos de los fármacos , Encuestas y Cuestionarios , Testosterona/farmacocinética , Congéneres de la Testosterona/farmacología , Adulto Joven
2.
Andrology ; 7(2): 235-243, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30556332

RESUMEN

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.


Asunto(s)
Anticonceptivos Masculinos/administración & dosificación , Anticonceptivos Masculinos/farmacocinética , Norprogesteronas/administración & dosificación , Norprogesteronas/farmacocinética , Testosterona/administración & dosificación , Testosterona/farmacocinética , Adulto , Femenino , Geles , Humanos , Masculino , Piel
3.
Andrology ; 7(1): 42-52, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30345711

RESUMEN

BACKGROUND: Ex vivo androgen prodrug conversion by blood esterases after oral androgen ester administration may result in an overestimation of the measured blood androgens. OBJECTIVE: We investigated whether blood collection tubes with esterase inhibitors decreased the conversion of testosterone undecanoate (TU) and dimethandrolone undecanoate (DMAU) to their active metabolites, testosterone (T), and dimethandrolone (DMA), providing a more accurate assessment of circulating T/DMA levels. METHODS: Blood was collected in tubes with/without esterase inhibitors from: (i) four healthy and four hypogonadal men receiving no androgens and spiked ex vivo with TU/DMAU; (ii) four men taking oral TU (Andriol® ); and (iii) eight hypogonadal men dosed with oral 316 mg TU and 15 healthy men with 200 mg DMAU. T/DMA levels were measured by LC-MS/MS. RESULTS: Sodium fluoride (NaF, an esterase inhibitor) decreased measured T levels by 14.2% in men not receiving TU. Increasing amounts of TU/DMAU added to blood collected into plain tubes resulted in a concentration-dependent overestimation of T/DMA that was reduced by collecting blood into NaF tubes (by 30-85%), and keeping samples at 4 °C and minimizing time prior to centrifugation. After oral TU/DMAU administration to men, when TU/DMAU levels were >15/10 ng/mL, respectively, blood collected in NaF tubes yielded lower measured T concentrations by 15-30% and DMA by 22% due to an additional inhibitory effect of NaF on blood esterases. CONCLUSION: NaF directly lowers plasma T/DMA levels measured by LC-MS/MS and also inhibits blood esterase activity. Overestimation of T/DMA in blood collected in tubes without NaF after oral TU/DMAU administration is important for pharmacokinetics studies in drug development clinical trials but may have limited impact in clinical practice/utilization because the differences between measured and true androgen values are modest and the wide therapeutic androgen efficacy ranges obviate the need for highly accurate androgen measurements during therapy.


Asunto(s)
Esterasas/metabolismo , Nandrolona/análogos & derivados , Fluoruro de Sodio/farmacología , Testosterona/análogos & derivados , Testosterona/sangre , Adolescente , Adulto , Cromatografía Liquida , Esterasas/antagonistas & inhibidores , Humanos , Hipogonadismo/tratamiento farmacológico , Hipogonadismo/patología , Persona de Mediana Edad , Nandrolona/sangre , Nandrolona/metabolismo , Nandrolona/uso terapéutico , Espectrometría de Masas en Tándem , Testosterona/metabolismo , Testosterona/uso terapéutico , Adulto Joven
4.
Andrology ; 5(2): 278-285, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27907978

RESUMEN

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.


Asunto(s)
Anticonceptivos Masculinos/farmacología , Nandrolona/análogos & derivados , Administración Oral , Adulto , Anticonceptivos Masculinos/efectos adversos , Anticonceptivos Masculinos/farmacocinética , Dihidrotestosterona/sangre , Método Doble Ciego , Sistemas de Liberación de Medicamentos , Estradiol/sangre , Hormona Folículo Estimulante/sangre , Humanos , Hormona Luteinizante/sangre , Masculino , Nandrolona/efectos adversos , Nandrolona/farmacocinética , Nandrolona/farmacología , Testosterona/sangre
5.
Andrology ; 3(3): 582-589, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25891800

RESUMEN

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.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/farmacología , Apoptosis/efectos de los fármacos , Ciclofosfamida/farmacología , Péptidos y Proteínas de Señalización Intracelular/farmacología , Células Intersticiales del Testículo/efectos de los fármacos , Animales , Cetoconazol/farmacología , Masculino , Mesilatos/farmacología , Ratas , Ratas Sprague-Dawley , Espermatozoides/patología , Testosterona/biosíntesis , Testosterona/sangre , Testosterona/metabolismo
6.
Endocrinology ; 155(2): 417-28, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24280056

RESUMEN

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.


Asunto(s)
Hígado Graso/tratamiento farmacológico , Terapia de Reemplazo de Hormonas , Hígado/efectos de los fármacos , Testosterona/uso terapéutico , Adiponectina/sangre , Animales , Apoptosis/efectos de los fármacos , Composición Corporal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Castración , Ingestión de Alimentos/efectos de los fármacos , Ácidos Grasos no Esterificados/sangre , Hígado Graso/metabolismo , Hígado Graso/patología , Insulina/sangre , Leptina/sangre , Hígado/metabolismo , Masculino , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
7.
Andrology ; 1(6): 899-905, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24123845

RESUMEN

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.


Asunto(s)
Norprogesteronas/farmacología , Administración Cutánea , Adolescente , Adulto , Anticonceptivos Masculinos/farmacología , Hormona Folículo Estimulante/sangre , Geles , Humanos , Hormona Luteinizante/sangre , Masculino , Persona de Mediana Edad , Norprogesteronas/administración & dosificación , Norprogesteronas/sangre , Espermatogénesis/efectos de los fármacos , Testosterona/administración & dosificación , Testosterona/sangre , Testosterona/farmacología
8.
Andrology ; 1(4): 651-9, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23686888

RESUMEN

We have previously demonstrated that the mitochondria-derived cytoprotective peptide humanin (HN), when administered intratesticularly to rats, rescues germ cells from apoptosis secondary to testicular stress of hormonal deprivation induced by gonadotropin-releasing hormone antagonist (GnRH-A). To decipher the cellular mechanisms of HN action in the amelioration of GnRH-A-induced germ cell apoptosis, adult male rats received the following treatments for 5 days: (i) daily intratesticular (IT) injections with saline (control); (ii) a single subcutaneous injection of GnRH-A on Day 1 and daily IT injection of saline; (iii) daily IT injection of synthetic HN; and (iv) GnRH-A injection on Day 1 and daily IT injection of HN (GnRH-A+HN). HN alone had no effect on germ cell apoptosis. GnRH-A increased germ cell apoptosis and BAX in the testicular mitochondrial fractions. Synthetic HN decreased germ cell apoptosis induced by GnRH-A and BAX in the mitochondria. We deduced that the cytoprotective action of synthetic HN on GnRH-A-induced germ cell apoptosis was mediated by attenuating p38 mitogen-activated protein kinase activity and increasing STAT3 phosphorylation. The effect of synthetic HN on the expression of endogenous rat HN in the testis was studied using rat HN specific antibody. GnRH-A treatment increased, but concomitant treatment with synthetic HN reduced endogenous rat HN expression in both cytosolic and mitochondrial fractions in testis. Co-immunoprecipitation experiments demonstrated that the increased rat HN was physically associated with BAX in the cytosolic testicular fractions after GnRH-A treatment. Double-immunofluorescence staining confirmed the co-localization of BAX and rat HN in the cytoplasm of Leydig cells and spermatocytes after GnRH-A treatment. We conclude that the cytoprotective effect of exogenously administered synthetic HN is mediated by interactions of endogenous rat HN with BAX in the cytoplasm preventing the entry of BAX to the mitochondria to govern the fate of germ cell survival or death during pro-apoptotic stress to the testis in rats.


Asunto(s)
Apoptosis , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Mitocondrias/metabolismo , Testículo/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Animales , Apoptosis/efectos de los fármacos , Citoprotección , Técnica del Anticuerpo Fluorescente , Inmunoprecipitación , Inyecciones Subcutáneas , Péptidos y Proteínas de Señalización Intracelular/administración & dosificación , Masculino , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Oligopéptidos/toxicidad , Fosforilación , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/administración & dosificación , Factor de Transcripción STAT3/metabolismo , Testículo/efectos de los fármacos , Testículo/patología , Factores de Tiempo , Regulación hacia Arriba , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
9.
J Clin Endocrinol Metab ; 98(6): 2422-9, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23559086

RESUMEN

CONTEXT: In the absence of panhypopituitarism and low serum IGF-I levels, the diagnosis of adult GH deficiency (AGHD) requires confirmation with a GH stimulation test. Macimorelin is a novel, orally active ghrelin mimetic that stimulates GH secretion. OBJECTIVE: The objective of the study was to determine the diagnostic efficacy and safety of macimorelin in AGHD. DESIGN: This was a multicenter open-label study comparing the diagnostic accuracy of oral macimorelin with that of arginine+GHRH in AGHD patients and healthy, matched controls. After 43 AGHD patients and 10 controls were tested, the GHRH analog Geref Diagnostic [GHRH(1-29)NH2] became unavailable in the United States. The study was completed by testing 10 additional AGHD patients and 38 controls with macimorelin alone. MAIN OUTCOME MEASURE: Peak GH area under the receiver operating characteristic curve after macimorelin was measured. RESULTS: Fifty AGHD subjects and 48 controls were evaluated. Peak GH levels in AGHD patients and controls after macimorelin were 2.36 ± 5.69 and 17.71 ± 19.11 ng/mL, respectively (P < .0001). With macimorelin, the receiver operating characteristic analysis yielded an optimal GH cut point of 2.7 ng/mL, with 82% sensitivity, 92% specificity, and 13% misclassification rate. For subjects receiving both tests, macimorelin showed discrimination comparable with arginine+GHRH (area under the receiver operating characteristic curve 0.99 vs 0.94, respectively, P = .29). Obesity (body mass index > 30 kg/m(2)) was present in 58% of subjects, and peak GH levels were inversely associated with body mass index in controls (r = -0.37, P = .01). Using the separate cut points of 6.8 ng/mL for nonobese and 2.7 for obese subjects reduced the misclassification rate to 11%. Only 1 drug-related serious adverse event, an asymptomatic QT interval prolongation on the electrocardiogram, was reported. CONCLUSION: Oral macimorelin is safe, convenient, and effective in diagnosing AGHD with accuracy comparable with the arginine+GHRH test.


Asunto(s)
Ghrelina/análogos & derivados , Hormona de Crecimiento Humana/deficiencia , Indoles , Triptófano/análogos & derivados , Administración Oral , Adulto , Anciano , Arginina , Estudios Cruzados , Femenino , Hormona Liberadora de Hormona del Crecimiento , Hormona de Crecimiento Humana/sangre , Humanos , Factor I del Crecimiento Similar a la Insulina/análisis , Masculino , Persona de Mediana Edad , Curva ROC
10.
Int J Androl ; 34(6 Pt 1): 541-7, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20969601

RESUMEN

Oral testosterone undecanoate (TU) is used to treat testosterone deficiency; however, oral TU treatment elevates dihydrotestosterone (DHT), which may be associated with an increased risk of acne, male pattern baldness and prostate hyperplasia. Co-administration of 5α-reductase inhibitors with other formulations of oral testosterone suppresses DHT production and increases serum testosterone. We hypothesized that finasteride would increase serum testosterone and lower DHT during treatment with oral TU. Therefore, we studied the steady-state pharmacokinetics of oral TU, 200 mg equivalents of testosterone twice daily for 7 days, alone and with finasteride 0.5 and 1.0 mg po twice daily in an open-label, three-way crossover study in 11 young men with experimentally induced hypogonadism. On the seventh day of each dosing period, serum testosterone, DHT and oestradiol were measured at baseline and 1, 2, 4, 8, 12, 13, 14, 16, 20 and 24 h after the morning dose. Serum testosterone and DHT were significantly increased into and above their normal ranges similarly by all three treatments. Co-administration of finasteride at 0.5 and 1.0 mg po twice daily had no significant effect on either serum testosterone or DHT. Oral TU differs from other formulations of oral testosterone in its response to concomitant inhibition of 5α-reductase, perhaps because of its unique lymphatic route of absorption.


Asunto(s)
Colestenona 5 alfa-Reductasa/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Finasterida/farmacología , Testosterona/análogos & derivados , Administración Oral , Adolescente , Adulto , Estudios Cruzados , Dihidrotestosterona/sangre , Humanos , Masculino , Persona de Mediana Edad , Testosterona/administración & dosificación , Testosterona/farmacocinética , Adulto Joven
11.
Int J Androl ; 33(4): 581-7, 2010 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-19622086

RESUMEN

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.


Asunto(s)
Células Germinativas/trasplante , Síndrome de Klinefelter/genética , Testículo/citología , Animales , Diferenciación Celular , Proliferación Celular , Proteínas Fluorescentes Verdes/genética , Masculino , Ratones , Ratones Transgénicos , Espermatozoides/citología
14.
Int J Impot Res ; 21(1): 1-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-18923415

RESUMEN

The new ISA, ISSAM, EAU, EAA and ASA recommendations on the investigation, treatment and monitoring of late-onset hypogonadism in males provide updated evidence-based information for clinicians who diagnose and treat patients with adult onset, age related testosterone deficiency.


Asunto(s)
Hipogonadismo/diagnóstico , Hipogonadismo/terapia , Guías de Práctica Clínica como Asunto , Factores de Edad , Edad de Inicio , Humanos , Hipogonadismo/sangre , Masculino , Sociedades Médicas , Testosterona/sangre
15.
Int J Impot Res ; 21(2): 89-98, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-18843273

RESUMEN

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.


Asunto(s)
Disfunción Eréctil/complicaciones , Obesidad/complicaciones , Testosterona/sangre , Testosterona/deficiencia , Tejido Adiposo/patología , Andrógenos/uso terapéutico , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Disfunción Eréctil/sangre , Disfunción Eréctil/tratamiento farmacológico , Disfunción Eréctil/patología , Humanos , Masculino , Síndrome Metabólico/sangre , Síndrome Metabólico/patología , Obesidad/sangre , Obesidad/tratamiento farmacológico , Obesidad/patología
18.
J Clin Endocrinol Metab ; 91(4): 1423-7, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16403821

RESUMEN

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.


Asunto(s)
Encéfalo/patología , Trastornos del Conocimiento/patología , Trastornos del Conocimiento/psicología , Síndrome de Klinefelter/patología , Síndrome de Klinefelter/psicología , Adolescente , Adulto , Ventrículos Cerebrales/patología , Femenino , Lateralidad Funcional/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Testosterona/farmacología
20.
J Endocrinol Invest ; 28(3 Suppl): 109-11, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16042368

RESUMEN

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.


Asunto(s)
Terapia de Reemplazo de Hormonas , Testosterona/administración & dosificación , Anciano , Envejecimiento , Contraindicaciones , Humanos , Hipogonadismo/tratamiento farmacológico , Masculino , Testosterona/efectos adversos , Testosterona/deficiencia , Resultado del Tratamiento
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