RESUMO
Forty percent of US pregnancies are unintended despite currently available contraceptives. A substantial number of men use the currently available methods of male contraception, condoms and vasectomy, and a large majority would be interested in novel forms of male contraception if available. Research into male contraception has been ongoing for more than 50 years, with hormonal contraceptives nearing clinical utility and non-hormonal methods hopefully becoming available, albeit with a longer time frame. However, uncertainly regarding benchmarks for the efficacy and safety of male contraception continue to be an issue with development and regulatory approval. In addition, pharmaceutical industry support is minimal with the NIH and Foundations being the main research funders. Given the continuing high rates of unintended pregnancy, many of which are now occurring in areas with extremely restricted access to legal abortion, additional focus and investment in male contraceptive development is imperative.
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Anticoncepcionais Masculinos , Gravidez , Feminino , Masculino , Humanos , Anticoncepção , Anticoncepcionais , PreservativosRESUMO
The economic and public health burdens of unplanned pregnancies are evident globally. Since the introduction of the condom >300 years ago, assumptions about male willingness to participate in contraception, as well as concerns about failure rates and side effects, have stagnated the development of additional reversible male contraceptives. However, changing attitudes and recent research advances have generated renewed interest in developing reversible male contraceptives. To achieve effective and reversible suppression of spermatogenesis, male hormonal contraception relies on suppression of testicular testosterone and sperm production using an androgen-progestin combination. While these may be associated with side effects-changes in libido, weight, hematocrit, and cholesterol-recently, novel androgens and progestins have shown promise for a "male pill" with reduced side effects. Here we summarize landmark studies in male contraceptive development, showcase the most recent advances, and look into the future of this field, which has the potential to greatly impact global public health.
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Anticoncepção/métodos , Anticoncepcionais Masculinos/administração & dosagem , Contracepção Hormonal/métodos , Taxa de Gravidez , Progestinas/administração & dosagem , Administração Cutânea , Androgênios/administração & dosagem , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Contracepção Hormonal/efeitos adversos , Humanos , Masculino , Gravidez , Testosterona/administração & dosagem , Resultado do TratamentoRESUMO
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 , MasculinoRESUMO
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 XRESUMO
Unintended pregnancy is a global public health problem. Despite a variety of female contraceptive options, male contraceptive options are limited to the condom and vasectomy. Condoms have high failure rates and surgical vasectomy is not reliably reversible. There is a global need and desire for novel male contraceptive methods. Hormonal methods have progressed the furthest in clinical development and androgen plus progestin formulations hold promise as a marketable, reversible male contraceptive over the next decade. Investigators have tested androgen plus progestin approaches using oral, transdermal, subdermal, and injectable drug formulations and demonstrated the short-term safety and reversibility of hormonal male contraception. The most commonly reported side effects associated with hormonal male contraception include weight gain, acne, slight suppression of serum high-density cholesterol, mood changes, and changes in libido. Efficacy trials of hormonal male contraceptives have demonstrated contraceptive efficacy rates greater than that of condoms. Although there has been less progression in the development of nonhormonal male contraceptives, potentially reversible vaso-occlusive methods are currently in clinical trials in some countries. Various studies have confirmed both men and women's desire for novel male contraceptives. Barriers to development include an absence of investment from pharmaceutical companies, concerns regarding side effects and spermatogenic rebound with hormonal methods, and lack of clear reversibility and proven effectiveness of nonhormonal methods. The ultimate availability of male contraceptives could have an important impact on decreasing global unintended pregnancy rates (currently 40% of all pregnancies) and will be a step towards reproductive justice and greater equity in family planning.
Assuntos
Anticoncepção , Serviços de Planejamento Familiar , Feminino , Humanos , Masculino , GravidezRESUMO
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 JovemRESUMO
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/sangueRESUMO
OBJECTIVE: Total testosterone concentrations are influenced by sex hormone-binding globulin (SHBG) concentrations, which are decreased by obesity and increased with ageing. Therefore, we sought to understand and compare the associations of ageing and obesity with SHBG. DESIGN: We performed a retrospective, cross-sectional analysis of the associations of obesity and age on SHBG and testosterone measurements in men being evaluated for hypogonadism. PATIENTS, MEASUREMENTS AND ANALYSIS: A total of 3671 men who underwent laboratory testing for testosterone deficiency from the Veterans Administration Puget Sound Health Care System from 1997 through 2007 was included. Univariate and multivariate linear regression modelling of the associations between age and body mass index (BMI) and SHBG was performed. RESULTS: Obesity was associated with a significantly lower SHBG [ß = -1·26 (95% CI -1·14, -1·38) nmol/l] per unit increase in BMI. In contrast, ageing was associated with a significantly increased SHBG [ß = 0·46 (95% CI 0·39, 0·53) nmol/l per year] (P < 0·001 for both effects). The association of obesity with lower SHBG was two to three times larger than the association of ageing with increased SHBG in both univariate and multivariate modelling. On average, obese men (BMI >30 kg/m(2)) had significantly lower SHBG and total testosterone concentrations than nonobese men [(mean ± SD) SHBG: 36 ± 22 vs 50 ± 27 nmol/l and total testosterone: 10·5 ± 5·4 nmol/l vs 14·1 ± 7·4 nmol/l; (P < 0·001 for both comparisons)], but calculated free testosterone concentrations did not differ between obese and nonobese men. CONCLUSIONS: We found that the association between obesity and lowered SHBG is greater than the association of ageing with increased SHBG. These competing effects may impact total testosterone measurements for the diagnosis of low testosterone, particularly in obese men.
Assuntos
Envelhecimento/metabolismo , Obesidade/metabolismo , Globulina de Ligação a Hormônio Sexual/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/sangue , Envelhecimento/fisiologia , Índice de Massa Corporal , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Estudos Retrospectivos , Testosterona/sangue , Adulto JovemRESUMO
PURPOSE OF REVIEW: Rates of unintended pregnancy have remained relatively stagnant for many years, despite a broad array of female contraceptive options. Recent restrictions on access to abortion in some countries have increased the urgency for expanding contraceptive options. Increasing data suggest men are keen to utilize novel reversible male contraceptives. RECENT FINDINGS: Despite decades of clinical research in male contraception, no reversible hormonal product currently exists. Nestorone/testosterone, among other novel androgens, shows promise to finally move to pivotal Phase 3 studies and introduction to the marketplace. SUMMARY: Hormonal male contraception utilizes androgens or androgen-progestin combinations to exploit negative feedback that regulates the hypothalamic-pituitary-testicular axis. By suppressing release of gonadotropins, these agents markedly decrease endogenous testosterone production, lower intratesticular testosterone and suppress spermatogenesis. The addition of a progestin enhances the degree and speed of sperm suppression. The androgen component preserves a state of symptomatic eugonadism in the male. There is growing demand and acceptance of male contraceptive options in various forms. As these formulations progress through stages of drug development, regulatory oversight and communication with developers around safety and efficacy standards and garnering industry support for advancing the production of male contraceptives will be imperative.
RESUMO
INTRODUCTION: Male contraception with exogenously administered hormones suppresses both luteinizing hormone and follicle stimulating hormone leading to low intratesticular testosterone concentration. This results in reversible suppression of spermatogenesis and marked decrease in sperm output in the ejaculate and preventing pregnancy in the female partner. PRIOR STUDIES: Studies of testosterone administered alone or in combination of another gonadotropin suppressive agent such as a progestin or gonadotropin releasing hormone (GnRH) analog showed decisively that the exogenous hormone administrations are effective in suppressing sperm output with few adverse events that are not anticipated. In contraceptive efficacy studies, testosterone alone or combined with a progestin are as effective in preventing pregnancies as female contraceptive methods. CONCLUSION: Hormone combinations for male contraception are in late-phase clinical trials and hold the promise of being the new, reversible contraception method for men in over half a century. Lessons learned from the male hormonal contraceptive development pave the way for new targeted approached to regulate male fertility.
Assuntos
Anticoncepcionais Masculinos , Testosterona , Humanos , Masculino , Anticoncepcionais Masculinos/farmacologia , Anticoncepcionais Masculinos/administração & dosagem , Contracepção Hormonal , Espermatogênese/efeitos dos fármacos , Feminino , Contraceptivos Hormonais/administração & dosagem , Contraceptivos Hormonais/efeitos adversos , Progestinas/administração & dosagem , Progestinas/efeitos adversosRESUMO
Injectable male hormonal contraceptives are effective for preventing pregnancy in clinical trials; however, users may prefer to avoid medical appointments and injections. A self-administered transdermal contraceptive gel may be more acceptable for long-term contraception. Transdermal testosterone gels are widely used to treat hypogonadism and transdermal administration may have utility for male contraception; however, no efficacy data from transdermal male hormonal contraceptive gel are available. We designed and are currently conducting an international, multicenter, open-label study of self-administration of a daily combined testosterone and segesterone acetate (Nestorone) gel for male contraception. The transdermal approach to male contraception raises novel considerations regarding adherence with the daily gel, as well as concern about the potential transfer of the gel and the contraceptive hormones to the female partner. Enrolled couples are in committed relationships. Male partners have baseline normal spermatogenesis and are in good health; female partners are regularly menstruating and at risk for unintended pregnancy. The study's primary outcome is the rate of pregnancy in couples during the study's 52-week efficacy phase. Secondary endpoints include the proportion of male participants suppressing sperm production and entering the efficacy phase, side effects, hormone concentrations in male participants and their female partners, sexual function, and regimen acceptability. Enrollment concluded on November 1, 2022, with 462 couples and enrollment is now closed. This report outlines the strategy and design of the first study to examine the contraceptive efficacy of a self-administered male hormonal contraceptive gel. The results will be presented in future reports. IMPLICATIONS: The development of a safe, effective, reversible male contraceptive would improve contraceptive options and may decrease rates of unintended pregnancy. This manuscript outlines the study design and analysis plan for an ongoing large international trial of a novel transdermal hormone gel for male contraception. Successful completion of this and future studies of this formulation may lead to the approval of a male contraceptive.
Assuntos
Anticoncepcionais Masculinos , Testosterona , Gravidez , Masculino , Humanos , Feminino , Sêmen , Anticoncepção/métodos , Anticoncepcionais , GéisRESUMO
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 â<â0.05). LTBI status was associated with higher IL-4 and IL-12p70 only among PWH, but not HIV-negative participants ( P â<â0.05 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 â<â0.05 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-InflamatóriosRESUMO
BACKGROUNDS: Despite a wide spectrum of contraceptive methods for women, the unintended pregnancy rate remains high (45% in the US), with 50% resulting in abortion. Currently, 20% of global contraceptive use is male-directed, with a wide variation among countries due to limited availability and lack of efficacy. Worldwide studies indicate that >50% of men would opt to use a reversible method, and 90% of women would rely on their partner to use a contraceptive. Additional reasons for novel male contraceptive methods to be available include the increased life expectancy, sharing the reproductive risks among partners, social issues, the lack of pharma industry involvement and the lack of opinion makers advocating for male contraception. AIM: The present guidelines aim to review the status regarding male contraception, the current state of the art to support the clinical practice, recommend minimal requirements for new male contraceptive development and provide and grade updated, evidence-based recommendations from the European Society of Andrology (EAA) and the American Society of Andrology (ASA). METHODS: An expert panel of academicians appointed by the EAA and the ASA generated a consensus guideline according to the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) system. RESULTS: Sixty evidence-based and graded recommendations were produced on couple-centered communication, behaviors, barrier methods, semen analysis and contraceptive efficacy, physical agents, surgical methods, actions before initiating male contraception, hormonal methods, non-hormonal methods, vaccines, and social and ethical considerations. CONCLUSION: As gender roles transform and gender equity is established in relationships, the male contribution to family planning must be facilitated. Efficient and safe male-directed methods must be evaluated and introduced into clinical practice, preferably reversible, either hormonal or non-hormonal. From a future perspective, identifying new hormonal combinations, suitable testicular targets, and emerging vas occlusion methods will produce novel molecules and products for male contraception.
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The effects of androgens on cardiovascular disease (CVD) risk in men remain unclear. To better characterize the relationship between androgens and HDL, we investigated the effects of testosterone replacement on HDL protein composition and serum HDL-mediated cholesterol efflux in hypogonadal men. Twenty-three older hypogonadal men (ages 51-83, baseline testosterone < 280 ng/dl) were administered replacement testosterone therapy (1% transdermal gel) with or without the 5α-reductase inhibitor dutasteride. At baseline and after three months of treatment, we determined fasting lipid concentrations, HDL protein composition, and the cholesterol efflux capacity of serum HDL. Testosterone replacement did not affect HDL cholesterol (HDL-C) concentrations but conferred significant increases in HDL-associated paraoxonase 1 (PON1) and fibrinogen α chain (FGA) (P = 0.022 and P = 0.023, respectively) and a decrease in apolipoprotein A-IV (apoA-IV) (P = 0.016). Exogenous testosterone did not affect the cholesterol efflux capacity of serum HDL. No differences were observed between men who received testosterone alone and those who also received dutasteride. Testosterone replacement in older hypogonadal men alters the protein composition of HDL but does not significantly change serum HDL-mediated cholesterol efflux. These effects appear independent of testosterone conversion to dihydrotestosterone. Further research is needed to determine how changes in HDL protein content affect CVD risk in men.
Assuntos
HDL-Colesterol/metabolismo , Hipogonadismo/tratamento farmacológico , Proteoma/efeitos dos fármacos , Testosterona/uso terapêutico , HDL-Colesterol/sangue , Jejum , Humanos , Hipogonadismo/sangue , Hipogonadismo/metabolismo , Masculino , Pessoa de Meia-Idade , Testosterona/administração & dosagem , Testosterona/farmacologiaRESUMO
Despite significant advances in contraceptive options for women over the last 50 yr, world population continues to grow rapidly. Scientists and activists alike point to the devastating environmental impacts that population pressures have caused, including global warming from the developed world and hunger and disease in less developed areas. Moreover, almost half of all pregnancies are still unwanted or unplanned. Clearly, there is a need for expanded, reversible, contraceptive options. Multicultural surveys demonstrate the willingness of men to participate in contraception and their female partners to trust them to do so. Notwithstanding their paucity of options, male methods including vasectomy and condoms account for almost one third of contraceptive use in the United States and other countries. Recent international clinical research efforts have demonstrated high efficacy rates (90-95%) for hormonally based male contraceptives. Current barriers to expanded use include limited delivery methods and perceived regulatory obstacles, which stymie introduction to the marketplace. However, advances in oral and injectable androgen delivery are cause for optimism that these hurdles may be overcome. Nonhormonal methods, such as compounds that target sperm motility, are attractive in their theoretical promise of specificity for the reproductive tract. Gene and protein array technologies continue to identify potential targets for this approach. Such nonhormonal agents will likely reach clinical trials in the near future. Great strides have been made in understanding male reproductive physiology; the combined efforts of scientists, clinicians, industry and governmental funding agencies could make an effective, reversible, male contraceptive an option for family planning over the next decade.
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Anticoncepção/tendências , Anticoncepção/métodos , Anticoncepção/psicologia , Anticoncepcionais Masculinos/uso terapêutico , Anticoncepcionais Orais Hormonais/uso terapêutico , Humanos , Masculino , Modelos Biológicos , Aceitação pelo Paciente de Cuidados de Saúde , Espermatogênese/efeitos dos fármacos , Espermatogênese/fisiologia , Testículo/efeitos dos fármacos , Testículo/fisiologiaRESUMO
Rates of unplanned pregnancies are high globally, burdening women and families. Efforts to develop male contraceptive agents have been thwarted by unacceptable failure rates, side effects and a dearth of pharmaceutical industry involvement. Hormonal male contraception consists of exogenous androgens which exert negative feedback on the hypothalamic-pituitary-gonadal axis and suppress gonadotropin production. This in turn suppresses testicular testosterone production and sperm maturation. Addition of a progestin suppresses spermatogenesis more effectively in men. Contraceptive efficacy studies in couples have shown male hormonal methods are effective and reversible, but also may come with side effects related to sexual desire, acne and serum cholesterol and inconvenient methods of dosing and delivery. Recently, novel androgens as potential contraceptive agents are being evaluated in early clinical trials and look to overcome these drawbacks. Here we summarize landmark studies of prototype male hormonal contraceptives, showcasing recent advances and future prospects in this important area of public health.
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Androgênios , Anticoncepcionais Masculinos , Colesterol/farmacologia , Anticoncepção/métodos , Anticoncepcionais Masculinos/farmacologia , Anticoncepcionais Masculinos/uso terapêutico , Feminino , Gonadotropinas , Humanos , Masculino , Gravidez , Progestinas/farmacologia , Sêmen , Espermatogênese , Testosterona/farmacologia , Testosterona/uso terapêuticoRESUMO
Rates of unplanned pregnancies are high and stagnant globally, burdening women, families and the environment. Local limitations placed upon contraceptive access and abortion services exacerbate global disparities for women. Despite survey data suggesting men and their partners are eager for expanded male contraceptive options, efforts to develop such agents have been stymied by a paucity of monetary investment. Modern male hormonal contraception, like female hormonal methods, relies upon exogenous progestins to suppress the hypothalamic-pituitary-gonadal axis, in turn suppressing testicular testosterone production and sperm maturation. Addition of an androgen augments gonadotropin suppression, more effectively suppressing spermatogenesis in men, and provides androgenic support for male physiology. Previous contraceptive efficacy studies in couples have shown that hormonal male methods are effective and reversible. Recent efforts have been directed at addressing potential user and regulatory concerns by utilizing novel steroids and varied routes of hormone delivery. Provision of effective contraceptive options for men and women is an urgent public health need. Recognizing and addressing the gaps in our contraceptive options and engaging men in family planning will help reduce rates of unplanned pregnancies in the coming decades.
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Anticoncepcionais Masculinos , Contracepção Hormonal , Androgênios/farmacologia , Anticoncepção/métodos , Anticoncepcionais Masculinos/farmacologia , Feminino , Humanos , Masculino , Gravidez , Espermatogênese , Testosterona/farmacologiaRESUMO
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 (Pâ <â .001) but HDL particle size did not change significantly. SARM had minimal effect on CEC of HDL particles (changeâ +â 0.016, -0.036, +0.070, and -0.048%/µmol-HDL/L-1 at 0, 1, 5, and 15 mg SARM, Pâ =â .045). SARM treatment suppressed APOAI (Pâ <â .001) but not APOB (Pâ =â .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) (Pâ <â .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.
RESUMO
OBJECTIVE: To assess men's preferences for healthcare provider from whom they would obtain hormonal male contraceptive (HMC) methods. STUDY DESIGN: We asked participants from 3 clinical trials of investigational HMC methods-an oral pill (11ß-Methyl-19-nortestosterone-17ß-dodecylcarbonate, 11ß-MNTDC), intramuscular or subcutaneous injection (Dimethandrolone undecanoate), and transdermal gel (Nestorone and testosterone)-to rank their top 3 preferred HMC providers from a list including: men's health doctor (urologist/andrologist), hormonal doctor (endocrinologist), reproductive health doctor (OB/GYN), family planning clinician (community health worker, midwife, nurse practitioner), regular doctor (family medicine/internal medicine), and community pharmacist. We examined preferences based on their rankings and conducted bivariate analyses. Collapsing the various specialists (men's health doctor, hormonal doctor, reproductive health doctor, and family planning clinician) into a single provider type, we examined participant demographics against provider preference (regular doctor, pharmacist, or specialist). RESULTS: Participants across the 3 trials (n = 124) ranked their regular doctor (44%) and community pharmacist (18%) as their most preferred HMC provider; these preferences did not differ significantly by trial and drug formulation. Specialists in family planning (13%), men's health (12%), reproductive health (10%), and hormones (4%) were least frequently ranked as their preferred provider. Older and higher educated participants more often preferred specialists over regular doctors and pharmacists (p = 0.02 and p = 0.01). CONCLUSIONS: Despite receiving contraceptive steroid hormones and care from endocrinologists and family planning specialists in a clinical trial, participants would prefer to obtain contraception from their regular doctor. IMPLICATIONS: As most men expect to obtain hormonal male contraceptives from their regular doctor when commercially available, primary care physicians should become familiar with HMCs and be prepared to provide counseling and options accordingly.
Assuntos
Anticoncepcionais Masculinos , Nandrolona , Ensaios Clínicos como Assunto , Anticoncepção/métodos , Anticoncepcionais Masculinos/uso terapêutico , Serviços de Planejamento Familiar , Humanos , Masculino , TestosteronaRESUMO
The carotid intimal media thickness (CIMT) is a validated measure of subclinical atherosclerosis. Human immunodeficiency virus (HIV) is a risk factor for cardiovascular disease (CVD) and has been associated with CIMT in North America and Europe; however, there are limited data from Sub-Saharan Africa (SSA). In this cross-sectional study, we measured CIMT in a cohort of 262 people living with HIV (PLHIV) on antiretroviral therapy (ART) forâ ≥6 months and HIV-negative adults in western Kenya. Using linear regression, we examined the associations between CVD risk factors and CIMT, both overall and stratified according to the HIV status. Among the PLHIV, we examined the association between CIMT and HIV-related factors. Of 262 participants, approximately half were women. The HIV-negative group had a higher prevalence of ageâ ≥55 years (Pâ =â .002), previously diagnosed hypertension (Pâ =â .02), treatment for hypertension (Pâ =â .03), and elevated blood pressure (BP) (Pâ =â .01). Overall prevalence of carotid plaques was low (15/262 [6.0%]). HIV-positive status was not significantly associated with a greater mean CIMT (Pâ =â .19). In multivariable regression models, PLHIV with elevated blood pressure or treatment for hypertension had a greater mean CIMT (Pâ =â .002). However, the CD4 count, viral load, and ART regimen were not associated with differences in CIMT. In the HIV-negative group, older age (Pâ =â .006), high total cholesterol levels (Pâ =â .01), and diabetes (Pâ =â .02) were associated with a greater mean CIMT. In this cross-sectional study of Kenyan adults, traditional CVD risk factors were found to be more prevalent among HIV-negative participants. After multivariable regression analysis, we found no association between HIV status and CIMT, and PLHIV had fewer CVD risk factors associated with CIMT than HIV-negative participants did. HIV-specific factors were not associated with the CIMT.