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1.
AIDS ; 37(7): 1065-1075, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36928263

RESUMO

BACKGROUND: Persons with HIV (PWH) on antiretroviral therapy (ART) have persistent immune activation associated with increased risk for non-AIDS related diseases. Latent tuberculosis infection (LTBI), endemic in Africa, may contribute to this immune dysregulation. We evaluated the impact of HIV and TB co-infection on plasma pro- and anti-inflammatory cytokines among Kenyan adults. METHODS: We compared data from 221 PWH on long-term ART and 177 HIV-negative adults examining biomarkers of pro-[sCD14, interleukin (IL)-2, IL-6, interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), IL-12p70, IL-17A] and anti(IL-4, IL-5, IL-13) inflammatory cytokines, by HIV/LTBI status (HIV+LTBI+, HIV+LTBI-, HIV-LTBI+, HIV-LTBI-). LTBI was diagnosed based on a positive QuantiFERON TB Gold-Plus test in the absence of active TB symptoms. Linear regression was used to evaluate the associations of HIV, LTBI, and HIV/LTBI status with biomarkers adjusting for clinical factors including HIV-specific factors. RESULTS: Half of the participants were women and 52% had LTBI. HIV was independently associated with higher sCD14, IL-15, IL-6, IL-4, IL-5. LTBI was independently associated with higher TNF-α, IL-12p70, IL-17A, IL-4, IL-13 in adjusted models ( P  < 0.05). LTBI status was associated with higher IL-4 and IL-12p70 only among PWH, but not HIV-negative participants ( P  < 0.05 for interactions). In multivariate analysis, only HIV+LTBI+ demonstrated elevated levels of TNF-α, IL-6, IL-12p70, IL-15, IL-17A, IL4, IL-5, IL-13 in comparison to the HIV-LTBI- ( P  < 0.05 for all). The effect of LTBI on cytokines among PWH was independent of CD4 + T-cell count and ART duration. CONCLUSIONS: Despite viral suppression, persons with HIV and LTBI exhibit abnormal cytokine production accompanied by high concentrations of pro- and anti-inflammatory cytokines.


Assuntos
Infecções por HIV , Tuberculose Latente , Adulto , Masculino , Humanos , Feminino , Citocinas , Tuberculose Latente/diagnóstico , Tuberculose Latente/tratamento farmacológico , Interleucina-17 , Interleucina-15/uso terapêutico , Quênia , Fator de Necrose Tumoral alfa , Interleucina-13 , Interleucina-4 , Interleucina-5/uso terapêutico , Interleucina-6 , Receptores de Lipopolissacarídeos , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Biomarcadores , Anti-Inflamatórios
2.
J Endocr Soc ; 6(8): bvac099, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35822201

RESUMO

Context: Selective androgen receptor modulators (SARMs), because of their preferential muscle vs prostate selectivity, are being developed for muscle-wasting conditions. Oral SARMs suppress high-density lipoprotein cholesterol (HDL-C) but their effects on functional capacity and atherogenic potential of HDL particles are unknown. Objective: To determine the effects of an oral SARM (OPK-88004) on cholesterol efflux capacity, HDL particle number and size, apolipoprotein particle number and size and HDL subspecies. Methods: We measured cholesterol efflux capacity (CEC); HDL particle number and size; APOB; APOA1; and protein-defined HDL subspecies associated with coronary heart disease (CHD) risk in men, who had undergone prostatectomy for low-grade prostate cancer during 12-week treatment with placebo or 1, 5, or 15 mg of an oral SARM (OPK-88004). Results: SARM significantly suppressed HDL-C (P < .001) but HDL particle size did not change significantly. SARM had minimal effect on CEC of HDL particles (change + 0.016, -0.036, +0.070, and -0.048%/µmol-HDL/L-1 at 0, 1, 5, and 15 mg SARM, P = .045). SARM treatment suppressed APOAI (P < .001) but not APOB (P = .077), and reduced APOA1 in HDL subspecies associated with increased (subspecies containing α2-macroglobulin, complement C3, or plasminogen) as well as decreased (subspecies containing APOC1 or APOE) CHD risk; relative proportions of APOA1 in these HDL subspecies did not change. SARM increased hepatic triacylglycerol lipase (HTGL) (P < .001). Conclusion: SARM treatment suppressed HDL-C but had minimal effect on its size or cholesterol efflux function. SARM reduced APOA1 in HDL subspecies associated with increased as well as decreased CHD risk. SARM-induced increase in HTGL could contribute to HDL-C suppression. These data do not support the simplistic notion that SARM-associated suppression of HDL-C is necessarily proatherogenic; randomized trials are needed to determine SARM's effects on cardiovascular events.

3.
Andrology ; 9(5): 1526-1539, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33908182

RESUMO

BACKGROUND: Dimethandrolone (DMA) and 11ß-methyl-19-nortestosterone (11ß-MNT) are two novel compounds with both androgenic and progestational activity that are under investigation as potential male hormonal contraceptives. Their metabolic effects have never been compared in men. OBJECTIVE: Assess for changes in insulin sensitivity and adiponectin and compare the metabolic effects of these two novel androgens. MATERIALS/METHODS: In two clinical trials of DMA undecanoate (DMAU) and 11ß-MNT dodecylcarbonate (11ß-MNTDC), oral prodrugs of DMA and 11ß-MNT, healthy men received drug, or placebo for 28 days. Insulin and adiponectin assays were performed on stored samples. Mixed model analyses were performed to compare the effects of the two drugs. Student's t test, or the non-parametric Kruskal-Wallis test as appropriate, was used to evaluate for an effect of active drug versus placebo. RESULTS: Class effects were seen, with decrease in HDL-C and SHBG, and increase in weight and hematocrit, with no statistically significant differences between the two compounds. No changes in fasting glucose, fasting insulin, or HOMA-IR were seen with either compound. There was a slight decrease in adiponectin with DMAU that was not seen with 11ß-MNTDC. An increase in LDL-C was seen with 11ß-MNTDC but not with DMAU. DISCUSSION: There were no significant changes in insulin resistance after 28 days of oral administration of these novel androgens despite a mild increase in weight. There may be subtle differences in their metabolic impacts that should be explored in future studies. CONCLUSION: Changes in metabolic parameters should be carefully monitored when investigating androgenic compounds.


Assuntos
Androgênios/farmacologia , Anticoncepcionais Masculinos/farmacologia , Nandrolona/análogos & derivados , Adiponectina/sangue , Administração Oral , Adulto , Glicemia/efeitos dos fármacos , HDL-Colesterol/efeitos dos fármacos , LDL-Colesterol/efeitos dos fármacos , Jejum/sangue , Voluntários Saudáveis , Hematócrito , Humanos , Insulina/sangue , Resistência à Insulina , Masculino , Nandrolona/farmacologia , Globulina de Ligação a Hormônio Sexual/efeitos dos fármacos , Aumento de Peso/efeitos dos fármacos , Adulto Jovem
4.
Clin Infect Dis ; 73(7): e2034-e2042, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33313687

RESUMO

BACKGROUND: Systemic inflammation independently predicts future cardiovascular events and is associated with a 2-fold increase in cardiovascular disease (CVD) risk among persons living with human immunodeficiency virus (PLHIV). We examined the association between inflammatory markers, HIV status, and traditional CVD risk factors. METHODS: We conducted a cross-sectional study of Kenyan adults with and without HIV seeking care at Kisumu County Hospital. Using a multiplex immunoassay, we measured interleukin (IL) 1ß, IL-6, tumor necrosis factor α (TNF-α), and high-sensitivity C-reactive protein (hsCRP) concentrations. We compared inflammatory marker concentrations by HIV status using the Wilcoxon rank-sum test. Multivariable linear regression was used to evaluate associations between inflammatory biomarkers and HIV status, adjusting for CVD risk factors. RESULTS: We enrolled 286 PLHIV and 277 HIV-negative participants. Median duration of antiretroviral therapy for PLHIV was 8 years (interquartile range, 4-10) and 96% were virally suppressed. PLHIV had a 51% higher mean IL-6 concentration (P < .001), 39% higher mean IL-1ß (P = .005), 40% higher mean TNF-α (P < .001), and 27% higher mean hsCRP (P = .008) compared with HIV-negative participants, independent of CVD risk factors. Male sex, older age, and obesity were associated with higher concentrations of inflammatory markers. Restricting to PLHIV, viral load of ≥1000 copies/mL was associated with higher TNF-α levels (P = .013). CONCLUSIONS: We found higher levels of systemic inflammatory biomarkers among PLHIV who were virally suppressed, and this was independent of traditional CVD risk factors. Further longitudinal analyses to determine whether these inflammatory markers predict future CVD events, and are possible therapeutic targets among PLHIV, are warranted.


Assuntos
Infecções por HIV , Adulto , Idoso , Biomarcadores , Estudos Transversais , HIV , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Inflamação/epidemiologia , Quênia/epidemiologia , Masculino
5.
J Clin Endocrinol Metab ; 106(1): e171-e181, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33090208

RESUMO

CONTEXT: Dimethandrolone undecanoate (DMAU) is being developed as a male contraceptive. Daily oral administration of DMAU, a potent androgen that is not aromatized, markedly suppresses serum testosterone (T) and estradiol (E2) in healthy men. E2 deficiency can increase bone resorption in men. OBJECTIVE: This work aimed to assess changes in bone turnover markers with DMAU administration in a 28-day study. DESIGN: A randomized, double-blind, placebo-controlled study was conducted. SETTING: This study took place at 2 academic medical centers. PARTICIPANTS: Healthy men, age 18 to50 years (n = 81), participated. INTERVENTION: Men received 0, 100, 200, or 400 mg of oral DMAU for 28 days. Serum C-terminal telopeptide of type I collagen (CTX; bone resorption marker) and procollagen type I amino-terminal propeptide (P1NP; bone formation marker) were measured on days 1 and 28. MAIN OUTCOME MEASURES: Changes in bone turnover markers and serum hormones over the treatment period were measured. RESULTS: On day 28, median serum T and E2 were markedly suppressed in all treatment groups vs placebo (P < .001 for both). Percentage change (%) in serum P1NP significantly differed across treatment groups (P = .007): Serum P1NP significantly increased in the 200 mg (5%, interquartile range [IQR] -7% to 27%) and 400 mg (22%, IQR -1% to 40%) groups relative to placebo (-8%, IQR -20% to 0%). Change (%) in serum CTX did not differ between groups (P = .09). CONCLUSIONS: DMAU administration for 28 days to healthy men leads to marked suppression of serum T and E2, yet increases P1NP, a serum marker of bone formation. Longer-term studies of the potent androgen DMAU are warranted to determine its impact on bone health in men.


Assuntos
Remodelação Óssea/efeitos dos fármacos , Nandrolona/análogos & derivados , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Adolescente , Adulto , Fosfatase Alcalina/sangue , Biomarcadores/sangue , Colágeno Tipo I/sangue , Anticoncepcionais Masculinos/farmacologia , Método Duplo-Cego , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Nandrolona/farmacologia , Peptídeos/sangue , Placebos , Fatores de Tempo , Estados Unidos , Regulação para Cima/efeitos dos fármacos , Adulto Jovem
6.
Clin Endocrinol (Oxf) ; 93(5): 555-563, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32633813

RESUMO

OBJECTIVE: Ageing in male adults is typically accompanied by adiposity accumulation and changes in circulating sex hormone concentrations. We hypothesized that an ageing-associated increase in oestrogens and decrease in androgens would correlate with an increase in adiposity. DESIGN: 10-year prospective, observational study. STUDY SUBJECTS: A total of 190, community-dwelling men in the Japanese American Community Diabetes Study. MEASUREMENTS: At 0 and 10 years, CT scanning quantified intra-abdominal fat (IAF) and subcutaneous fat (SCF) areas while plasma concentrations of oestradiol, oestrone, testosterone and dihydrotestosterone were measured by liquid chromatography-tandem-mass spectrometry at each time point. Multivariate linear regression analyses assessed correlations between 10-year changes in hormone concentrations and IAF or SCF, adjusting for age and baseline fat depot area. RESULTS: Participants were middle-aged [median 54.8 years, interquartile range (IQR) 39.9-62.8] men and mostly overweight by Asian criterion (median BMI 24.9, IQR 23.3-27.1) and with few exceptions had normal sex-steroid concentrations. Median oestradiol and dihydrotestosterone did not change significantly between 0 and 10 years (P = .084 and P = .596, respectively) while median oestrone increased (P < .001) and testosterone decreased (P < .001). Median IAF and SCF increased from 0 to 10 years (both P < .001). In multivariate analyses, change in oestrone positively correlated (P = .019) while change in testosterone (P = .003) and dihydrotestosterone (P = .014) negatively correlated with change in IAF. Plasma oestradiol and oestrone positively correlated with change in SCF (P = .041 and P = .030, respectively) while testosterone (P = .031) negatively correlated in multivariate analysis. CONCLUSION: Among 190 community-dwelling, Japanese American men, increases in IAF were associated with decreases in plasma androgens and increases in plasma oestrone, but not oestradiol, at 10 years. Further research is necessary to understand whether changing hormone concentrations are causally related to changes in regional adiposity or whether the reverse is true.


Assuntos
Adiposidade , Asiático , Adulto , Estradiol , Estrona , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Testosterona , Tomografia Computadorizada por Raios X
7.
J Clin Endocrinol Metab ; 105(3)2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31976519

RESUMO

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


Assuntos
Estrenos/administração & dosagem , Gonadotropinas/sangue , Administração Oral , Adolescente , Adulto , Anticoncepção/métodos , Anticoncepcionais Masculinos/administração & dosagem , Anticoncepcionais Masculinos/efeitos adversos , Anticoncepcionais Masculinos/farmacocinética , Método Duplo-Cego , Regulação para Baixo/efeitos dos fármacos , Esquema de Medicação , Estrenos/efeitos adversos , Estrenos/farmacocinética , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
J Clin Lipidol ; 12(4): 1072-1082, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29793828

RESUMO

BACKGROUND: Exogenous testosterone decreases serum concentrations of high-density lipoprotein cholesterol (HDL-C) in men, but whether this alters cardiovascular risk is uncertain. OBJECTIVE: To investigate the effects of testosterone and estradiol on HDL particle concentration (HDL-Pima) and metrics of HDL function. METHODS: We enrolled 53 healthy men, 19 to 55 years of age, in a double-blinded, placebo-controlled, randomized trial. Subjects were rendered medically castrate using the GnRH receptor antagonist acyline and administered either (1) placebo gel, (2) low-dose transdermal testosterone gel (1.62%, 1.25 g), (3) full replacement dose testosterone gel (1.62%, 5 g) or (4) full replacement dose testosterone gel together with an aromatase inhibitor for 4 weeks. At baseline and end of treatment, serum HDL total macrophage and ABCA1-specific cholesterol efflux capacity (CEC), HDL-Pima and size, and HDL protein composition were determined. RESULTS: Significant differences in serum HDL-C were observed with treatment across groups (P = .01 in overall repeated measures ANOVA), with increases in HDL-C seen after both complete and partial testosterone deprivation. Medical castration increased total HDL-Pima (median [interquartile range] 19.1 [1.8] nmol/L at baseline vs 21.3 [3.1] nmol/L at week 4, P = .006). However, corresponding changes in total macrophage CEC and ABCA1-specific CEC were not observed. Change in serum 17ß-estradiol concentration correlated with change in total macrophage CEC (ß = 0.33 per 10 pg/mL change in serum 17ß-estradiol, P = .03). CONCLUSIONS: Testosterone deprivation in healthy men leads to a dissociation between changes in serum HDL-C and HDL CEC. Changes in serum HDL-C specifically due to testosterone exposure may not reflect changes in HDL function.


Assuntos
HDL-Colesterol/sangue , Oligopeptídeos/administração & dosagem , Testosterona/administração & dosagem , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Adulto , Inibidores da Aromatase/administração & dosagem , Doenças Cardiovasculares/diagnóstico , Linhagem Celular , HDL-Colesterol/química , Método Duplo-Cego , Estradiol/sangue , Humanos , Injeções Subcutâneas , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula , Efeito Placebo , Testosterona/sangue , Testosterona/farmacologia , Adulto Jovem
9.
Asian J Androl ; 20(3): 276-283, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29205180

RESUMO

Androgen deprivation in men leads to increased adiposity, but the mechanisms underlying androgen regulation of fat mass have not been fully defined. Androgen receptor (AR) is expressed in monocytes/macrophages, which are resident in key metabolic tissues and influence energy metabolism in surrounding cells. Male mice bearing a cell-specific knockout of the AR in monocytes/macrophages (M-ARKO) were generated to determine whether selective loss of androgen signaling in these cells would lead to altered body composition. Wild-type (WT) and M-ARKO mice (12-22 weeks of age, n = 12 per group) were maintained on a regular chow diet for 8 weeks and then switched to a high-fat diet for 8 additional weeks. At baseline and on both the regular chow and high-fat diets, no differences in lean mass or fat mass were observed between groups. Consistent with the absence of differential body weight or adiposity, no differences in food intake (3.0 ± 0.5 g per day for WT mice vs 2.8 ± 0.4 g per day for M-ARKO mice) or total energy expenditure (0.6 ± 0.1 Kcal h-1 for WT mice vs 0.5 ± 0.1 Kcal h-1 for M-ARKO mice) were evident between groups during high-fat feeding. Liver weight was greater in M-ARKO than that in WT mice (1.5 ± 0.1 g vs 1.3 ± 0.0 g, respectively, P = 0.02). Finally, M-ARKO mice did not exhibit impairments in glucose tolerance or insulin sensitivity relative to WT mice at any study time point. In aggregate, these findings suggest that AR signaling specifically in monocytes/macrophages does not contribute to the regulation of systemic energy balance, adiposity, or insulin sensitivity in male mice.


Assuntos
Adiposidade/genética , Fígado/anatomia & histologia , Macrófagos/metabolismo , Monócitos/metabolismo , Receptores Androgênicos/genética , Animais , Glicemia/genética , Glicemia/metabolismo , Metabolismo Energético/genética , Teste de Tolerância a Glucose , Homeostase/genética , Masculino , Camundongos , Camundongos Knockout , Tamanho do Órgão , Receptores Androgênicos/metabolismo , Transdução de Sinais
10.
Am J Physiol Endocrinol Metab ; 313(5): E528-E539, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28698282

RESUMO

Male hypogonadism results in changes in body composition characterized by increases in fat mass. Resident immune cells influence energy metabolism in adipose tissue and could promote increased adiposity through paracrine effects. We hypothesized that manipulation of circulating sex steroid levels in healthy men would alter adipose tissue immune cell populations. Subjects (n = 44 men, 19-55 yr of age) received 4 wk of treatment with the gonadotropin-releasing hormone receptor antagonist acyline with daily administration of 1) placebo gel, 2) 1.25 g testosterone gel (1.62%), 3) 5 g testosterone gel, or 4) 5 g testosterone gel with an aromatase inhibitor. Subcutaneous adipose tissue biopsies were performed at baseline and end-of-treatment, and adipose tissue immune cells, gene expression, and intra-adipose estrogen levels were quantified. Change in serum total testosterone level correlated inversely with change in the number of CD3+ (ß = -0.36, P = 0.04), CD4+ (ß = -0.34, P = 0.04), and CD8+ (ß = -0.33, P = 0.05) T cells within adipose tissue. Change in serum 17ß-estradiol level correlated inversely with change in the number of adipose tissue macrophages (ATMs) (ß = -0.34, P = 0.05). A negative association also was found between change in serum testosterone and change in CD11c+ ATMs (ß = -0.41, P = 0.01). Overall, sex steroid deprivation was associated with increases in adipose tissue T cells and ATMs. No associations were found between changes in serum sex steroid levels and changes in adipose tissue gene expression. Circulating sex steroid levels may regulate adipose tissue immune cell populations. These exploratory findings highlight a possible novel mechanism that could contribute to increased metabolic risk in hypogonadal men.


Assuntos
Tecido Adiposo/citologia , Tecido Adiposo/imunologia , Hormônios Esteroides Gonadais/fisiologia , Imunidade Celular/fisiologia , Adulto , Inibidores da Aromatase/farmacologia , Antígeno CD11c/metabolismo , Complexo CD3/metabolismo , Antígenos CD4/metabolismo , Estradiol/farmacologia , Regulação da Expressão Gênica , Hormônios Esteroides Gonadais/sangue , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Receptores LHRH/antagonistas & inibidores , Linfócitos T/imunologia , Testosterona/sangue , Testosterona/farmacologia , Adulto Jovem
11.
Endocr Rev ; 38(3): 220-254, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472278

RESUMO

Benefits associated with lowered serum DHT levels after 5α-reductase inhibitor (5AR-I) therapy in men have contributed to a misconception that circulating DHT levels are an important stimulus for androgenic action in target tissues (e.g., prostate). Yet evidence from clinical studies indicates that intracellular concentrations of androgens (particularly in androgen-sensitive tissues) are essentially independent of circulating levels. To assess the clinical significance of modest elevations in serum DHT and the DHT/testosterone (T) ratio observed in response to common T replacement therapy, a comprehensive review of the published literature was performed to identify relevant data. Although the primary focus of this review is about DHT in men, we also provide a brief overview of DHT in women. The available published data are limited by the lack of large, well-controlled studies of long duration that are sufficiently powered to expose subtle safety signals. Nonetheless, the preponderance of available clinical data indicates that modest elevations in circulating levels of DHT in response to androgen therapy should not be of concern in clinical practice. Elevated DHT has not been associated with increased risk of prostate disease (e.g., cancer or benign hyperplasia) nor does it appear to have any systemic effects on cardiovascular disease safety parameters (including increased risk of polycythemia) beyond those commonly observed with available T preparations. Well-controlled, long-term studies of transdermal DHT preparations have failed to identify safety signals unique to markedly elevated circulating DHT concentrations or signals materially different from T.


Assuntos
Di-Hidrotestosterona , Inibidores de 5-alfa Redutase/farmacologia , Animais , Di-Hidrotestosterona/sangue , Di-Hidrotestosterona/química , Di-Hidrotestosterona/metabolismo , Di-Hidrotestosterona/farmacologia , Feminino , Humanos , Masculino , Próstata/efeitos dos fármacos , Próstata/metabolismo , Neoplasias da Próstata/sangue , Caracteres Sexuais , Testosterona/farmacologia , Testosterona/fisiologia
12.
Clin Endocrinol (Oxf) ; 87(1): 59-67, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28370068

RESUMO

OBJECTIVE: Serum sex steroid concentrations may alter body composition and glucose homoeostasis in men in a dose-response manner. We evaluated these end-points in healthy men rendered medically castrate through use of a gonadotrophin-releasing hormone antagonist (acyline) with incremental doses of exogenous testosterone (T) gel. DESIGN: Subjects (n=6-9 per group) were randomly assigned to injections of acyline every 2 weeks plus transdermal T gel (1.25 g, 2.5 g, 5.0 g, 10 g or 15 g) daily or double placebo (injections and gel) for 12 weeks. PATIENTS: Healthy men, ages 25-55 years, with normal serum total T concentrations. MEASUREMENTS: Serum T, dihydrotestosterone (DHT) and oestradiol (E2) were measured at baseline and every 2 weeks. Body composition was analysed by dual-energy X-ray absorptiometry at baseline and week 12. Fasting serum adiponectin, leptin, glucose and insulin concentrations were measured at baseline and week 10. RESULTS: Forty-eight men completed the study. A significant treatment effect was observed for change in lean mass (ANOVAP=.01) but not fat mass (P=.14). Lean mass increased in the 15 g T group relative to all lower dose groups, except the 10 g T group. When all subjects were analysed together, changes in lean mass correlated directly and changes in fat mass correlated inversely with serum T, E2 and DHT. No changes were noted in serum glucose, insulin or adipokine levels. CONCLUSIONS: In healthy men, higher serum concentrations of T, DHT and E2 were associated with greater increases in lean mass and decreases in fat mass but not with changes in serum glucose, insulin or adipokines.


Assuntos
Adipocinas/sangue , Composição Corporal/efeitos dos fármacos , Hormônios Esteroides Gonadais/administração & dosagem , Testosterona/administração & dosagem , Adulto , Glicemia , Di-Hidrotestosterona/sangue , Relação Dose-Resposta a Droga , Estradiol/sangue , Hormônios Esteroides Gonadais/sangue , Voluntários Saudáveis , Antagonistas de Hormônios , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/administração & dosagem , Testosterona/sangue
13.
J Clin Endocrinol Metab ; 101(10): 3724-3731, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27482750

RESUMO

CONTEXT: T deprivation increases risk of insulin resistance in men, but whether this risk is independent of changes in body composition is unknown. Further, the metabolic roles of T and its metabolite estradiol have not been clearly defined in men. OBJECTIVE: This study sought to establish the effects of selective sex steroid withdrawal on insulin sensitivity in healthy men. DESIGN, SETTING, AND PARTICIPANTS: This was a double-blinded, placebo-controlled, randomized trial at an academic medical center of 56 healthy men, 19-55 years of age. INTERVENTIONS: Subjects received the GnRH antagonist acyline plus one of the following: placebo gel (Castrate), 1.25 g testosterone gel (Low T/E), 5 g testosterone gel (Normal T/E), or 5 g testosterone gel with letrozole (Normal T/Low E) daily for 4 weeks. Body composition and glucose tolerance were assessed at baseline and end of treatment. MAIN OUTCOME MEASURE: Insulin sensitivity was quantified by the Matsuda index. RESULTS: Predicted circulating sex steroid concentrations were achieved in all treatment groups. The time-by-group interaction for Matsuda index did not achieve significance in overall repeated measures ANOVA (baseline vs week 4; P = .16). A significant time-by-group interaction was observed for fat mass (P = .003), with changes in fat mass attributable predominantly to estrogen exposure in linear regression analysis (P = .016). A time-by-group interaction also was observed for lean mass (P = .03) and influenced by androgen exposure (P = .003). CONCLUSIONS: Short-term sex steroid withdrawal in healthy men causes adverse changes in body composition. These findings support the role of estradiol as a determinant of adiposity in men.


Assuntos
Adiposidade , Androgênios/farmacologia , Inibidores da Aromatase/farmacologia , Glicemia/metabolismo , Estradiol/sangue , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Antagonistas de Hormônios/farmacologia , Resistência à Insulina , Testosterona , Adulto , Androgênios/administração & dosagem , Inibidores da Aromatase/administração & dosagem , Método Duplo-Cego , Antagonistas de Hormônios/administração & dosagem , Humanos , Letrozol , Masculino , Pessoa de Meia-Idade , Nitrilas/administração & dosagem , Nitrilas/farmacologia , Testosterona/administração & dosagem , Testosterona/sangue , Testosterona/farmacologia , Triazóis/administração & dosagem , Triazóis/farmacologia , Adulto Jovem
14.
J Clin Endocrinol Metab ; 101(7): 2937-44, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27172434

RESUMO

CONTEXT: Concern exists that T replacement therapy (TRT) might increase the risk of prostate disease. There are limited data regarding the impact of TRT on prostate androgen concentrations. OBJECTIVE: Determine the dose-dependent effects of exogenous T administration on intraprostatic androgen concentrations. DESIGN: Twelve-week, double-blinded, randomized, placebo-controlled trial. SETTING: Academic medical center. PARTICIPANTS: Sixty-two healthy eugonadal men, aged 25-55 years. INTERVENTIONS: Subjects were randomly assigned to receive injections of acyline, a GnRH antagonist (used to achieve medical castration), every 2 weeks plus transdermal T gel (1.25 g, 2.5 g, 5.0 g, 10 g, or 15 g daily), or placebo injections and transdermal gel for 12 weeks. MAIN OUTCOMES: Serum T and dihydrotestosterone (DHT) were measured at baseline and every 2 weeks during treatment. Intraprostatic T and DHT concentrations were assessed from tissue obtained through ultrasound-guided prostate needle biopsies at week 12. Androgens were quantified by liquid chromatography-tandem mass spectrometry. RESULTS: 51 men completed the study and were included in the analysis. There were no significant adverse events. Exogenous T resulted in a dose-dependent increase in serum T and DHT concentrations (190-770 and 60-180 ng/dL, respectively). Although intraprostatic T differed among dose groups (P = .01), intraprostatic DHT was comparable regardless of T dose (P = .11) and was 10- to 20-fold greater than intraprostatic T. CONCLUSIONS: In healthy, medically castrate men receiving exogenous T, the total intraprostatic androgen concentration (predominantly DHT) remained stable across serum T concentrations within the physiological range. These findings further our knowledge of the relationship between serum and intraprostatic androgens and suggest that physiological serum T achieved by TRT is unlikely to alter the prostate hormonal milieu.


Assuntos
Di-Hidrotestosterona/metabolismo , Oligopeptídeos/administração & dosagem , Orquiectomia , Próstata/metabolismo , Testosterona/uso terapêutico , Adulto , Hormônio Liberador de Gonadotropina/agonistas , Saúde , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Orquiectomia/métodos , Próstata/efeitos dos fármacos , Testosterona/farmacologia , Resultado do Tratamento
15.
Pharmacol Ther ; 163: 109-17, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27016468

RESUMO

World population continues to grow at an unprecedented rate, doubling in a mere 50years to surpass the 7-billion milestone in 2011. This steep population growth exerts enormous pressure on the global environment. Despite the availability of numerous contraceptive choices for women, approximately half of all pregnancies are unintended and at least half of those are unwanted. Such statistics suggest that there is still a gap in contraceptive options for couples, particularly effective reversible contraceptives for men, who have few contraceptive choices. Male hormonal contraception has been an active area of research for almost 50years. The fundamental concept involves the use of exogenous hormones to suppress endogenous production of gonadotropins, testosterone, and downstream spermatogenesis. Testosterone-alone regimens are effective in many men but high dosing requirements and sub-optimal gonadotropin suppression in 10-30% of men limit their use. A number of novel combinations of testosterone and progestins have been shown to be more efficacious but still require further refinement in delivery systems and a clearer understanding of the potential short- and long-term side effects. Recently, synthetic androgens with both androgenic and progestogenic activity have been developed. These agents have the potential to be single-agent male hormonal contraceptives. Early studies of these compounds are encouraging and there is reason for optimism that these may provide safe, reversible, and reliable contraception for men in the near future.


Assuntos
Antiespermatogênicos/farmacologia , Antiespermatogênicos/uso terapêutico , Progestinas/farmacologia , Progestinas/uso terapêutico , Testosterona/farmacologia , Androgênios/farmacologia , Antiespermatogênicos/administração & dosagem , Antiespermatogênicos/efeitos adversos , Acetato de Ciproterona/uso terapêutico , Vias de Administração de Medicamentos , Quimioterapia Combinada , Hormônio Foliculoestimulante/metabolismo , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Gonadotropinas/metabolismo , Humanos , Hormônio Luteinizante/metabolismo , Masculino , Progestinas/administração & dosagem , Progestinas/efeitos adversos , Espermatogênese/fisiologia
16.
Obes Res Clin Pract ; 10(6): 624-632, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26747209

RESUMO

PROBLEM: The role of plasma estradiol in the accumulation of intra-abdominal fat (IAF) in men is uncertain. Cross-sectional studies using imaging of IAF have shown either a positive or no association. In contrast, a randomised controlled trial using an aromatase inhibitor to suppress estradiol production found an association between oestrogen deficiency and short-term IAF accumulation. No longitudinal study has been conducted to examine the relationship between plasma estradiol concentration and the change in IAF area measured using direct imaging. METHODS: This is a longitudinal observational study in community-dwelling Japanese-American men (n=215, mean age 52 years, BMI 25.4kg/m2). IAF and subcutaneous fat areas were assessed using computerized tomography (CT) at baseline, 5 and 10 years. Baseline plasma estradiol concentrations were measured using liquid chromatography-tandem mass spectrometry. RESULTS: Univariate analysis found no association between baseline estradiol concentration and baseline IAF, or 5- or 10-year changes in IAF area (r=-0.05 for both time points, p=0.45 and p=0.43, respectively). Multivariate linear regression analysis of the change in IAF area by baseline estradiol concentration adjusted for age, baseline IAF area, and weight change found no association with either the 5- or 10-year IAF area change (p=0.52 and p=0.55, respectively). CONCLUSIONS: Plasma estradiol concentration was not associated with baseline IAF nor with change in IAF area over 5 or 10 years based on serial CT scans in community-dwelling Japanese-American men. These results do not support a role for oestrogen deficiency in IAF accumulation in men.


Assuntos
Estradiol/sangue , Gordura Intra-Abdominal/metabolismo , Abdome , Adulto , Asiático , Humanos , Japão/etnologia , Modelos Lineares , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal/sangue , Estudos Prospectivos
17.
Asian J Androl ; 18(1): 21-4, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26208394

RESUMO

Measurement of intratesticular sex steroid concentrations in men informs both the development of male hormonal contraceptives and the understanding of male infertility. Given the challenges of using invasive techniques to measure testicular hormone physiology, our group has used a minimally-invasive fine-needle aspiration technique to measure intratesticular hormones in normal healthy men. Herein, we present a post-hoc analysis of the safety and efficacy of testicular fine-needle aspiration (FNA) completed as part of six clinical trials. From 2001 through 2011, a total of 404 procedures were conducted among 163 research volunteers, 85.9% of which were successful in obtaining sufficient fluid for the measurement of intratesticular steroid concentrations. Pain was the most common side effect, with 36.8% of procedures associated with moderate procedural pain and 4.7% with severe procedural pain. Postprocedural pain was uncommon and abated within a few days. Mild local bruising occurred with 14.9% of procedures. Two serious adverse events (0.5%) required surgical intervention. The risk of an adverse event was not associated with age, body mass index, testicular size, or the volume of fluid aspirated. Testicular FNA to obtain fluid for measurement of intratesticular steroid concentrations frequently causes mild to moderate procedural pain, but serious adverse events occur rarely. Testicular FNA has been instrumental for defining human intratesticular hormone physiology and is a minimally-invasive, safe, effective method for obtaining fluid for research on testicular physiology and pathology.


Assuntos
Biópsia por Agulha , Testículo/metabolismo , Testosterona/metabolismo , Biópsia por Agulha/efeitos adversos , Humanos , Masculino , Dor Pós-Operatória
18.
Asian J Androl ; 16(2): 248-55, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24407178

RESUMO

A growing body of literature has established the anabolic benefi ts of testosterone (T) therapy in hypogonadal men. However, there remains a paucity of data regarding the risks of exogenous androgen use in older men and the potential for adverse effects on the prostate gland. Whether T therapy in older, hypogonadal men might worsen lower urinary tract symptoms or exacerbate, unmask, or even incite prostate cancer development has tempered enthusiasm for T therapy, while known prostatic disease has served as a relative contraindication to T therapy. Androgens are necessary for the development and maintenance of the prostate gland. However, epidemiologic studies do not consistently fi nd a positive relationship between endogenous serum androgen concentrations and the risk of prostate disease. Recent data demonstrate that 5α-reductase inhibitors decrease the risk of low-grade prostate cancer, suggesting that modifying androgen metabolism may have beneficial effects on prostate health, yet similar reductions in high-grade disease have not been observed, thereby questioning the true clinical benefits of these agents for chemoprevention. Knowing how to best investigate the relationship between androgens and the development of prostate disease given the lack of large, randomized trials is difficult. Accumulating data challenges the assumption that alterations in serum androgens have parallel effects within the prostate hormonal environment or change androgen-regulated processes within the gland. Long-term intervention studies are needed to truly ascertain the effects of androgen manipulation on prostate tissue and disease risk. However, available data do not support the notion that restoring serum androgens to normal physiologic ranges drives prostate disease.


Assuntos
Androgênios/fisiologia , Doenças Prostáticas/fisiopatologia , Neoplasias da Próstata/fisiopatologia , Humanos , Masculino
19.
J Clin Invest ; 123(10): 4410-22, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24018560

RESUMO

The activating receptor NK cell group 2 member D (NKG2D) mediates antitumor immunity in experimental animal models. However, whether NKG2D ligands contribute to tumor suppression or progression clinically remains controversial. Here, we have described 2 novel lines of "humanized" bi-transgenic (bi-Tg) mice in which native human NKG2D ligand MHC class I polypeptide-related sequence B (MICB) or the engineered membrane-restricted MICB (MICB.A2) was expressed in the prostate of the transgenic adenocarcinoma of the mouse prostate (TRAMP) model of spontaneous carcinogenesis. Bi-Tg TRAMP/MICB mice exhibited a markedly increased incidence of progressed carcinomas and metastasis, whereas TRAMP/MICB.A2 mice enjoyed long-term tumor-free survival conferred by sustained NKG2D-mediated antitumor immunity. Mechanistically, we found that cancer progression in TRAMP/MICB mice was associated with loss of the peripheral NK cell pool owing to high serum levels of tumor-derived soluble MICB (sMICB). Prostate cancer patients also displayed reduction of peripheral NK cells and high sMIC levels. Our study has not only provided direct evidence in "humanized" mouse models that soluble and membrane-restricted NKG2D ligands pose opposite impacts on cancer progression, but also uncovered a mechanism of sMIC-induced impairment of NK cell antitumor immunity. Our findings suggest that the impact of soluble NKG2D ligands should be considered in NK cell-based cancer immunotherapy and that our unique mouse models should be valuable for therapy optimization.


Assuntos
Neoplasias Ósseas/sangue , Carcinoma/sangue , Antígenos de Histocompatibilidade Classe I/sangue , Células Matadoras Naturais/fisiologia , Neoplasias Hepáticas/sangue , Neoplasias Pulmonares/sangue , Neoplasias da Próstata/sangue , Idoso , Animais , Neoplasias Ósseas/imunologia , Neoplasias Ósseas/secundário , Carcinoma/imunologia , Carcinoma/secundário , Linhagem Celular Tumoral , Proliferação de Células , Antígenos de Histocompatibilidade Classe I/fisiologia , Homeostase , Humanos , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/secundário , Metástase Linfática , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Transplante de Neoplasias , Neoplasias da Próstata/imunologia , Neoplasias da Próstata/patologia
20.
Fertil Steril ; 99(1): 132-139, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23040523

RESUMO

OBJECTIVE: To study the potential role for using serum biomarkers, including insulin-like factor 3 (INSL3), 17α-hydroxyprogesterone, antimüllerian hormone, and inhibin B, as correlates of intratesticular T (IT-T) concentrations in men. DESIGN: Prospective, randomized, controlled trial. SETTING: University-based medical center. PATIENT(S): Thirty-seven healthy men aged 18-50 years. INTERVENTION(S): All men received the GnRH antagonist acyline, plus very low doses of hCG (0 IU, 15 IU, 60 IU, or 125 IU) SC every other day or 7.5 g T gel daily (75 mg delivered). The IT-T concentrations obtained by percutaneous testicular aspiration with simultaneous serum protein and steroid concentrations were measured at baseline and after 10 days of treatment. MAIN OUTCOME MEASURE(S): Intratesticular and serum hormone and gonadotropin concentrations. RESULT(S): After 10 days of gonadotropin suppression, serum INSL3 decreased by more than 90% and correlated highly with IT-T concentrations. In contrast, serum inhibin B, antimüllerian hormone, and 17α-hydroxyprogesterone did not correlate with IT-T. Serum INSL3 increased with the dose of hCG administered and returned to baseline after treatment. CONCLUSION(S): Serum INSL3 correlates highly with IT-T and serum T concentrations during acute gonadotropin suppression in men. Human chorionic gonadotropin stimulates dose-dependent increases in INSL3 and IT-T in healthy men and might be a useful biomarker of IT-T concentration in some clinical settings. CLINICAL TRIAL REGISTRATION NUMBER: NCT# 00839319.


Assuntos
Gonadotropina Coriônica/farmacologia , Gonadotropinas/deficiência , Insulina/sangue , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testosterona/metabolismo , 17-alfa-Hidroxiprogesterona/sangue , Adolescente , Adulto , Hormônio Antimülleriano/sangue , Biomarcadores/sangue , Relação Dose-Resposta a Droga , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Humanos , Inibinas/sangue , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/farmacologia , Proteínas , Adulto Jovem
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