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1.
J Sex Med ; 18(5): 849-867, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33814355

RESUMO

BACKGROUND: The Global Consensus Position Statement on the Use of Testosterone Therapy for Women (Global Position Statement) recommended testosterone therapy for postmenopausal women with hypoactive sexual desire disorder (HSDD). AIM: To provide a clinical practice guideline for the use of testosterone including identification of patients, laboratory testing, dosing, post-treatment monitoring, and follow-up care in women with HSDD. METHODS: The International Society for the Study of Women's Sexual Health appointed a multidisciplinary panel of experts who performed a literature review of original research, meta-analyses, review papers, and consensus guidelines regarding testosterone use in women. Consensus was reached using a modified Delphi method. OUTCOMES: A clinically useful guideline following a biopsychosocial assessment and treatment approach for the safe and efficacious use of testosterone in women with HSDD was developed including measurement, indications, formulations, prescribing, dosing, monitoring, and follow-up. RESULTS: Although the Global Position Statement endorses testosterone therapy for only postmenopausal women, limited data also support the use in late reproductive age premenopausal women, consistent with the International Society for the Study of Women's Sexual Health Process of Care for the Management of HSDD. Systemic transdermal testosterone is recommended for women with HSDD not primarily related to modifiable factors or comorbidities such as relationship or mental health problems. Current available research supports a moderate therapeutic benefit. Safety data show no serious adverse events with physiologic testosterone use, but long-term safety has not been established. Before initiation of therapy, clinicians should provide an informed consent. Shared decision-making involves a comprehensive discussion of off-label use, as well as benefits and risks. A total testosterone level should not be used to diagnose HSDD, but as a baseline for monitoring. Government-approved transdermal male formulations can be used cautiously with dosing appropriate for women. Patients should be assessed for signs of androgen excess and total testosterone levels monitored to maintain concentrations in the physiologic premenopausal range. Compounded products cannot be recommended because of the lack of efficacy and safety data. CLINICAL IMPLICATIONS: This clinical practice guideline provides standards for safely prescribing testosterone to women with HSDD, including identification of appropriate patients, dosing, and monitoring. STRENGTHS & LIMITATIONS: This evidence-based guideline builds on a recently published comprehensive meta-analysis and the Global Position Statement endorsed by numerous societies. The limitation is that testosterone therapy is not approved for women by most regulatory agencies, thereby making prescribing and proper dosing challenging. CONCLUSION: Despite substantial evidence regarding safety, efficacy, and clinical use, access to testosterone therapy for the treatment of HSDD in women remains a significant unmet need. Parish SJ, Simon JA, Davis SR, et al. International Society for the Study of Women's Sexual Health Clinical Practice Guideline for the Use of Systemic Testosterone for Hypoactive Sexual Desire Disorder in Women. J Sex Med 2021;18:849-867.


Assuntos
Disfunções Sexuais Psicogênicas , Saúde Sexual , Feminino , Humanos , Libido , Masculino , Comportamento Sexual , Disfunções Sexuais Psicogênicas/tratamento farmacológico , Testosterona/uso terapêutico
2.
Climacteric ; 24(6): 533-550, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33792440

RESUMO

AIM: To provide a clinical practice guideline for the use of testosterone including identification of patients, laboratory testing, dosing, post-treatment monitoring, and follow-up care in women with hypoactive sexual desire disorder (HSDD). METHODS: The International Society for the Study of Women's Sexual Health appointed a multidisciplinary panel of experts who performed a literature review of original research, meta-analyses, review papers, and consensus guidelines regarding testosterone use in women. Consensus was reached using a modified Delphi method. OUTCOMES: A clinically useful guideline following a biopsychosocial assessment and treatment approach for the safe and efficacious use of testosterone in women with HSDD was developed including measurement, indications, formulations, prescribing, dosing, monitoring, and follow-up. RESULTS: Although the Global Position Statement endorses testosterone therapy for only postmenopausal women, limited data also support the use in late reproductive age premenopausal women, consistent with the International Society for the Study of Women's Sexual Health Process of Care for the Management of HSDD. Systemic transdermal testosterone is recommended for women with HSDD not primarily related to modifiable factors or comorbidities such as relationship or mental health problems. Current available research supports a moderate therapeutic benefit. Safety data show no serious adverse events with physiologic testosterone use, but long-term safety has not been established. Before initiation of therapy, clinicians should provide an informed consent. Shared decision-making involves a comprehensive discussion of off-label use, as well as benefits and risks. A total testosterone level should not be used to diagnose HSDD, but as a baseline for monitoring. Government-approved transdermal male formulations can be used cautiously with dosing appropriate for women. Patients should be assessed for signs of androgen excess and total testosterone levels monitored to maintain concentrations in the physiologic premenopausal range. Compounded products cannot be recommended because of the lack of efficacy and safety data. CLINICAL IMPLICATIONS: This clinical practice guideline provides standards for safely prescribing testosterone to women with HSDD, including identification of appropriate patients, dosing, and monitoring. STRENGTHS AND LIMITATIONS: This evidence-based guideline builds on a recently published comprehensive meta-analysis and the Global Position Statement endorsed by numerous societies. The limitation is that testosterone therapy is not approved for women by most regulatory agencies, thereby making prescribing and proper dosing challenging. CONCLUSION: Despite substantial evidence regarding safety, efficacy, and clinical use, access to testosterone therapy for the treatment of HSDD in women remains a significant unmet need.


Assuntos
Disfunções Sexuais Psicogênicas , Saúde Sexual , Testosterona/uso terapêutico , Humanos , Masculino , Disfunções Sexuais Psicogênicas/tratamento farmacológico
3.
J Urol ; 203(4): 817-823, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31670607

RESUMO

PURPOSE: Although healthy young men demonstrate a diurnal pattern of serum testosterone, minimal information is available on diurnal variation in young men with testosterone deficiency. MATERIALS AND METHODS: Blood samples were obtained during a 24-hour period at 8 and 11 a.m., 2, 5 and 8 p.m., and 8 a.m. the following morning. Men were categorized with normal or low testosterone if serum testosterone was greater than 300 ng/dl or less than 300 ng/dl at 8 a.m., respectively. RESULTS: We studied 21 volunteers with a mean age of 31.7 years (range 18 to 49). Testosterone was normal in 11 men and low in 10 and all had a normal luteinizing hormone concentration. The low testosterone group was older (mean age 33.4 vs 30.1 years) with a higher body mass index (mean 32.6 vs 27.5 kg/m2) but the differences were not significant. The highest and lowest overall mean testosterone concentrations were observed at 8 a.m. and 2 p.m., respectively. Mean testosterone levels in the normal group declined between 8 a.m. and 2 p.m. from 423 to 358 ng/dl, representing a 15% decrease (p=0.0003). Mean testosterone in the low testosterone group was 228 ng/dl at 8 a.m. and 218 ng/dl at 2 p.m., representing a 4% decline (p=0.54). Calculated free testosterone paralleled total testosterone with a 14% decrease in the normal testosterone group (p <0.001) and a 5% decrease in the low testosterone group (p=0.52). Two of 11 men in the normal group showed no diurnal variation. No subject with baseline testosterone greater than 400 ng/dl had testosterone less than 300 ng/dl at any time point. CONCLUSIONS: Men with low testosterone failed to show diurnal variation on 24-hour blood sampling. We speculate that similar central mechanisms may be involved in the pathophysiology leading to secondary testosterone deficiency as well as the loss of circadian rhythms.


Assuntos
Ritmo Circadiano/fisiologia , Testosterona/sangue , Adolescente , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Testosterona/deficiência , Adulto Jovem
4.
Diabetes Obes Metab ; 22(11): 2055-2068, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32558149

RESUMO

AIMS: To investigate whether testosterone therapy (TTh) in men with hypogonadism and type 2 diabetes mellitus (T2DM) improves glycaemic control and insulin sensitivity, and results in remission of T2DM. MATERIAL AND METHODS: A total of 356 men who had total testosterone levels ≤12.1 nmol/L (350 ng/dL) and symptoms of hypogonadism were included in the study and followed up for 11 years. All patients received standard diabetes treatment and 178 patients additionally received parenteral testosterone undecanoate 1000 mg every 12 weeks following an initial 6-week interval. A control group comprised 178 hypogonadal patients who opted not to receive TTh. RESULTS: Patients with hypogonadism and T2DM treated with testosterone had significant progressive and sustained reductions in fasting glucose, glycated haemoglobin (HbA1c) and fasting insulin over the treatment period. In the control group, fasting glucose, HbA1c and fasting insulin increased. Among the patients treated with testosterone 34.3% achieved remission of their diabetes and 46.6% of patients achieved normal glucose regulation. Of the testosterone-treated group, 83.1% reached the HbA1c target of 47.5 mmol/mol (6.5%) and 90% achieved the HbA1c target of 53.0 mmol/mol (7%). In contrast, no remission of diabetes or reductions in glucose or HbA1c levels were noted in the control group. There were fewer deaths, myocardial infarctions, strokes and diabetic complications in the testosterone-treated group. CONCLUSIONS: Long-term TTh in men with T2DM and hypogonadism improves glycaemic control and insulin resistance. Remission of diabetes occurred in one-third of the patients. TTh is potentially a novel additional therapy for men with T2DM and hypogonadism.


Assuntos
Diabetes Mellitus Tipo 2 , Hipogonadismo , Glicemia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Hipogonadismo/complicações , Hipogonadismo/tratamento farmacológico , Hipogonadismo/epidemiologia , Masculino , Sistema de Registros , Testosterona/análogos & derivados
5.
J Urol ; 199(1): 257-265, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28728990

RESUMO

PURPOSE: We investigated the effects of long-term testosterone therapy on urinary and sexual function, and quality of life in hypogonadal men. MATERIALS AND METHODS: We performed an observational, prospective, cumulative registry study in 656 men with a mean ± SD age of 60.7 ± 7.2 years who had total testosterone 12.1 nmol/l or less and symptoms of hypogonadism. In the testosterone treated group 360 men received parenteral testosterone undecanoate 1,000 mg/12 weeks for up to 10 years. The 296 men who elected against testosterone therapy served as controls. From each group 82 patients were propensity matched by age, waist circumference and body mass index, resulting in 82 matched pairs of 164 men. Data were analyzed and estimated differences between the groups were adjusted for components of metabolic syndrome and quality of life. RESULTS: We found significant decreases in I-PSS (International Prostate Symptom Score) and post-void bladder volume (each p <0.0001) in patients receiving testosterone therapy but not in the untreated group. We recorded a decrease in AMS (Aging Males' Symptoms Scale) in the testosterone treated group but not in the untreated group (p <0.0001). We also recorded significant improvement in the IIEF-EF (International Index of Erectile Function-Erectile Function) domain in the testosterone treated group but not in the untreated group (p <0.0001). The improvement was maintained throughout followup. CONCLUSIONS: Long-term testosterone therapy in hypogonadal men resulted in significant improvements in urinary and sexual function, and in quality of life. In untreated hypogonadal men voiding and erectile function deteriorated with continued followup.


Assuntos
Androgênios/uso terapêutico , Hipogonadismo/tratamento farmacológico , Ereção Peniana/efeitos dos fármacos , Testosterona/análogos & derivados , Micção/efeitos dos fármacos , Idoso , Androgênios/farmacologia , Seguimentos , Humanos , Hipogonadismo/fisiopatologia , Masculino , Pessoa de Meia-Idade , Ereção Peniana/fisiologia , Estudos Prospectivos , Qualidade de Vida , Sistema de Registros/estatística & dados numéricos , Testosterona/farmacologia , Testosterona/uso terapêutico , Resultado do Tratamento , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/fisiopatologia , Micção/fisiologia
6.
Clin Endocrinol (Oxf) ; 89(1): 3-10, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29486065

RESUMO

OBJECTIVE: A label change in testosterone (T) products in March 2015 followed a highly publicized FDA advisory committee meeting in September 2014. Changes included a warning of possible increased cardiovascular (CV) risks and restriction of indicated populations to younger men with a limited set of known aetiologies of testosterone deficiency (TD). These changes greatly impacted clinical practice and public perception of T therapy (TTh). Our aim was to review these changes in the light of subsequently published studies. DESIGN: We identified 23 studies through June 2017, including 12 clinical trials and 11 observational studies. The Testosterone Trials included 790 men aged 65 years and older with TD without known aetiology, assigned to 1-year T gel or placebo. RESULTS: Demonstrated benefits of T included sexual activity and desire, physical activity and mood. There were 9 major adverse CV events (MACE) in the T arm and 16 in the placebo arm. No study reported increased MACE with TTh. A 3-year RCT showed no difference in carotid atherosclerosis. Several large observational studies reported reduced CV events with TTh, including one showing progressively reduced CV and mortality risk with greater duration of TTh. Men whose serum T normalized with TTh had reduced risk of MI and death compared with men whose T levels failed to normalize. CONCLUSION: We conclude that existing evidence fails to support increased CV risk with TTh; on the contrary, there is evidence suggestive of real-world CV benefits. Finally, existing evidence provides benefits of TTh in older men without known aetiology for T deficiency.


Assuntos
Terapia de Reposição Hormonal/normas , Testosterona/uso terapêutico , Doenças Cardiovasculares/induzido quimicamente , Sistema Cardiovascular/efeitos dos fármacos , Humanos , Fatores de Risco , Estados Unidos , United States Food and Drug Administration
7.
Gerontology ; 63(2): 144-156, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27855417

RESUMO

Frailty is a clinical condition related to changes in metabolism, to sarcopenia, and to decline in muscle mass and strength, bone mineral density, and physical function with aging. The pathophysiology of frailty is multifactorial and associated with comorbidities. Testosterone is implicated in regulating metabolic functions, maintenance of muscle and bone, and inhibition of adipogenesis. In older individuals, reduced testosterone is thought to contribute to an altered state of metabolism, loss of muscle and bone, and increased fat, leading to sarcopenia, sarcopenic obesity, and frailty. While no direct relationship between testosterone deficiency (commonly known as hypogonadism) and frailty has been established (due to the multifactorial nature of frailty), clinical evidence suggests that testosterone deficiency is associated with increased sarcopenia and obesity. Testosterone treatment in frail older men with limited mobility and with testosterone deficiency improved insulin resistance, glucose metabolism, and body composition. These changes contribute to better physical function and improved quality of life. Because frailty increases disability, comorbidities, and the risk of hospitalization, institutionalization, and mortality in older men, it is warranted to explore the potential usefulness of testosterone treatment in frail men with hypogonadism in order to attenuate the progression of sarcopenia and frailty. In this paper, we will discuss the impact of testosterone deficiency on frailty and the potential role of testosterone treatment in ameliorating and reducing the progression of frailty. Such an approach may reduce disability and the risk of hospitalization and increase functional independence and quality of life.


Assuntos
Envelhecimento/fisiologia , Idoso Fragilizado , Testosterona/deficiência , Testosterona/uso terapêutico , Acidentes por Quedas/prevenção & controle , Afeto/efeitos dos fármacos , Idoso , Envelhecimento/psicologia , Anemia/tratamento farmacológico , Anemia/etiologia , Composição Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Cognição/efeitos dos fármacos , Humanos , Resistência à Insulina , Masculino , Força Muscular/efeitos dos fármacos , Obesidade/complicações , Qualidade de Vida , Sarcopenia/tratamento farmacológico , Sarcopenia/etiologia , Sarcopenia/fisiopatologia
8.
Adv Exp Med Biol ; 1043: 473-526, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29224108

RESUMO

Androgens are steroid hormones with pleotropic and diverse biochemical and physiological functions, and androgen deficiency exerts a negative impact on human health. Testosterone (T) either directly or via its transformation into the more potent metabolite 5α-dihydrotestosterone (5α-DHT) or via aromatization into estradiol (E2) modulates important biochemical signaling pathways of human physiology and plays a critical role in the growth and/or maintenance of functions in a host of tissues and organs. T and 5α-DHT play an important role in regulating physiology of the muscle, adipose tissue, liver, bone, and central nervous system, as well as reproductive and sexual functions. Thus, androgen deficiency (also referred to as hypogonadism) is a well-recognized medical condition and if remained untreated will have a negative impact on human health and quality of life.In this chapter, we have summarized the negative impact of T deficiency (TD) on a host of physiological functions including reduced lean body mass (LBM), increased fat mass (FM), increased insulin resistance (IR), metabolic syndrome (MetS) and adiposity, reduced bone mineral density (BMD), anemia, sexual dysfunction, and reduced quality of life and increased mortality. In addition, we discuss another critical aspect of unrecognized form of androgen deficiency resulting from inhibition of 5α-reductases with drugs, such as finasteride and dutasteride, to block transformation of T into 5α-DHT in the course of treatment of benign prostatic hyperplasia (BPH) and male pattern hair loss, also known as androgenetic alopecia (AGA). The negative impact of drugs that inhibit transformation of T to 5α-DHT by 5α-reductases on metabolic function is manifested in fat accumulation in the liver, which may predispose to nonalcoholic fatty liver disease (NAFLD). Also, inhibition of 5α-DHT formation increases glucose synthesis and reduces glucose disposal potentially contributing to hyperglycemia, IR, and elevated activities of liver function enzymes concomitant with reduction in circulating T levels, worsening erectile dysfunction (ED), and reduced quality of life.Although we have attempted to summarize the current literature pertaining to this critical topic "androgen deficiency" and its impact on men's health and quality of life, there remain many gaps in the knowledge regarding the biochemical pathways that are involved in the pathophysiology of androgen deficiency. We wish to clearly state that there are areas of controversies, including whether age-related androgen deficiency (functional hypogonadism) merits treatment and whether T therapy provided real proven benefits. Finally, considerable debate exists with respect to the potential and purported cardiovascular (CV) risks of treating TD with exogenous T. For brevity sake, we will not discuss in detail the benefits of T therapy in men with TD since this topic is comprehensively covered by Dr. F. Saad's chapter in this book, entitled "Testosterone Therapy and Glucose Homeostasis in Men with Testosterone Deficiency (Hypogonadism)."We have made a concerted effort to address the controversy of T therapy in men with TD in the discussion. However, we wish to acknowledge that these issues will remain a matter of debate for some time to come. Only with advances in fundamental basic science and clinical research, some of these controversial issues may be laid to rest. Nevertheless, we believe that there is considerable body of credible evidence to suggest that T therapy of men with TD is safe and effective and provides a host of health benefits and therefore merits considerations in men with TD, irrespective of the underlying cause or etiology. An additional aspect of androgen deficiency is the drug-induced reduction in 5α-DHT levels by the use of 5α-reductase inhibitors. We also believe that physicians prescribing 5α-reductase inhibitors (i.e., finasteride or dutasteride) for relief of BPH symptoms or treatment of hair loss should engage their patients in a productive discussion regarding the potential adverse side effects of these medications on their overall health and quality of life.


Assuntos
Inibidores de 5-alfa Redutase/efeitos adversos , Metabolismo Energético/efeitos dos fármacos , Hipogonadismo/sangue , Comportamento Sexual/efeitos dos fármacos , Testosterona/deficiência , Nível de Saúde , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Hipogonadismo/induzido quimicamente , Hipogonadismo/tratamento farmacológico , Hipogonadismo/fisiopatologia , Masculino , Qualidade de Vida , Fatores de Risco , Fatores Sexuais , Disfunções Sexuais Fisiológicas/induzido quimicamente , Disfunções Sexuais Fisiológicas/fisiopatologia , Disfunções Sexuais Fisiológicas/psicologia , Disfunções Sexuais Psicogênicas/induzido quimicamente , Disfunções Sexuais Psicogênicas/fisiopatologia , Disfunções Sexuais Psicogênicas/psicologia , Testosterona/efeitos adversos , Testosterona/sangue
9.
Am J Physiol Regul Integr Comp Physiol ; 311(3): R566-73, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27488887

RESUMO

In the adult male, testosterone (T) deficiency (TD) also known as male hypogonadism, is a well-established medical condition, which has been recognized for more than a century. T therapy in men with TD was introduced as early as 1940s and was reported to improve overall health with no concomitant serious adverse effects. A wealth of recent studies demonstrated that T therapy in men with TD is associated with increased lean body mass, reduced fat mass and waist circumference, improvement in glycemic control, and reduced obesity. T therapy is also associated with improvements in lipid profiles, amelioration of metabolic syndrome (Met S) components, reduced inflammatory biomarkers, reduced systolic and diastolic blood pressure, and improvements in sexual function. More importantly, T therapy is associated with amelioration of diabetes and reduced mortality. However, few studies, marred with serious methodological and analytical flaws reported between 2010 and 2014, suggested that T therapy is associated with increased cardiovascular (CV) risk. As summarized in this review, a thorough and critical analysis of these studies showed that the risks purported are unsubstantiated and such studies lacked credible scientific and clinical evidence. Moreover, recent observational, registry studies, clinical trials, and meta-analyses, all revealed no increase in CV risks in men receiving T therapy. In this review, the benefits of T therapy in adult men with TD and the lack of credible evidence suggesting that T therapy is linked to increased CV risks are discussed. It should be noted that the literature is replete with studies demonstrating beneficial effects of T therapy on CV and overall health.


Assuntos
Doenças Cardiovasculares/mortalidade , Terapia de Reposição Hormonal/mortalidade , Hipogonadismo/tratamento farmacológico , Hipogonadismo/mortalidade , Testosterona/deficiência , Testosterona/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Causalidade , Comorbidade , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento
10.
Rev Endocr Metab Disord ; 16(3): 249-68, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26590935

RESUMO

Testosterone deficiency (TD) is a well-established and recognized medical condition that contributes to several co-morbidities, including metabolic syndrome, visceral obesity and cardiovascular disease (CVD). More importantly, obesity is thought to contribute to TD. This complex bidirectional interplay between TD and obesity promotes a vicious cycle, which further contributes to the adverse effects of TD and obesity and may increase the risk of CVD. Testosterone (T) therapy for men with TD has been shown to be safe and effective in ameliorating the components of the metabolic syndrome (Met S) and in contributiong to increased lean body mass and reduced fat mass and therefore contributes to weight loss. We believe that appropriate T therapy in obese men with TD is a novel medical approach to manage obesity in men with TD. Indeed, other measures of lifestyle and behavioral changes can be used to augment but not fully replace this effective therapeutic approach. It should be noted that concerns regarding the safety of T therapy remain widely unsubstantiated and considerable evidence exists supporting the benefits of T therapy. Thus, it is paramount that clinicians managing obese men with TD be made aware of this novel approach to treatment of obesity. In this review, we discuss the relationship between TD and obesity and highlight the contemporary advancement in management of obesity with pharmacological and surgical approaches, as well as utilization of T therapy and how this intervention may evolve as a novel approach to treatment of obesity in men with TD .


Assuntos
Doenças Cardiovasculares/etiologia , Obesidade/complicações , Testosterona/deficiência , Idoso , Humanos , Hipogonadismo/etiologia , Masculino , Síndrome Metabólica/etiologia , Obesidade/tratamento farmacológico , Obesidade/terapia , Obesidade Abdominal/etiologia , Testosterona/sangue , Testosterona/uso terapêutico , Redução de Peso
11.
Rev Endocr Metab Disord ; 16(3): 177-98, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26296373

RESUMO

Steroids are important physiological orchestrators of endocrine as well as peripheral and central nervous system functions. One of the key processes for regulation of these molecules lies in their enzymatic processing by a family of 5α-reductase (5α-Rs) isozymes. By catalyzing a key rate-limiting step in steroidogenesis, this family of enzymes exerts a crucial role not only in the physiological control but also in pathological events. Indeed, both 5α-R inhibition and supplementation of 5α-reduced metabolites are currently used or have been proposed as therapeutic strategies for a wide array of pathological conditions. In particular, the potent 5α-R inhibitors finasteride and dutasteride are used in the treatments of benign prostatic hyperplasia (BPH), as well as in male pattern hair loss (MPHL) known as androgenetic alopecia (AGA). Recent preclinical and clinical findings indicate that 5α-R inhibitors evoke not only beneficial, but also adverse effects. Future studies should investigate the biochemical and physiological mechanisms that underlie the persistence of the adverse sexual side effects to determine why a subset of patients is afflicted with such persistence or irreversible adverse effects. Also a better focus of clinical research is urgently needed to better define those subjects who are likely to be adversely affected by such agents. Furthermore, research on the non-sexual adverse effects such as diabetes, psychosis, depression, and cognitive function are needed to better understand the broad spectrum of the effects these drugs may elicit during their use in treatment of AGA or BPH. In this review, we will summarize the state of art on this topic, overview the key unresolved questions that have emerged on the pharmacological targeting of these enzymes and their products, and highlight the need for further studies to ascertain the severity and duration of the adverse effects of 5α-R inhibitors, as well as their biological underpinnings.


Assuntos
Inibidores de 5-alfa Redutase/efeitos adversos , Inibidores de 5-alfa Redutase/uso terapêutico , Alopecia/tratamento farmacológico , Animais , Sistema Nervoso Central/fisiologia , Colestenona 5 alfa-Redutase/deficiência , Colestenona 5 alfa-Redutase/fisiologia , Transtornos Cognitivos/induzido quimicamente , Depressão/induzido quimicamente , Diabetes Mellitus/induzido quimicamente , Dutasterida/efeitos adversos , Dutasterida/uso terapêutico , Finasterida/efeitos adversos , Finasterida/uso terapêutico , Humanos , Masculino , Hiperplasia Prostática/tratamento farmacológico , Neoplasias da Próstata/prevenção & controle , Psicoses Induzidas por Substâncias , Disfunções Sexuais Fisiológicas/induzido quimicamente , Esteroides/biossíntese
13.
J Lipid Res ; 55(7): 1434-47, 2014 07.
Artigo em Inglês | MEDLINE | ID: mdl-24837748

RESUMO

Here, we investigated how LDL receptor deficiency (Ldlr(-/-)) modulates the effects of testosterone on obesity and related metabolic dysfunctions. Though sham-operated Ldlr(-/-) mice fed Western-type diet for 12 weeks became obese and showed disturbed plasma glucose metabolism and plasma cholesterol and TG profiles, castrated mice were resistant to diet-induced obesity and had improved glucose metabolism and reduced plasma TG levels, despite a further deterioration in their plasma cholesterol profile. The effect of hypogonadism on diet-induced weight gain of Ldlr(-/-) mice was independent of ApoE and Lrp1. Indirect calorimetry analysis indicated that hypogonadism in Ldlr(-/-) mice was associated with increased metabolic rate. Indeed, mitochondrial cytochrome c and uncoupling protein 1 expression were elevated, primarily in white adipose tissue, confirming increased mitochondrial metabolic activity due to thermogenesis. Testosterone replacement in castrated Ldlr(-/-) mice for a period of 8 weeks promoted diet-induced obesity, indicating a direct role of testosterone in the observed phenotype. Treatment of sham-operated Ldlr(-/-) mice with the aromatase inhibitor exemestane for 8 weeks showed that the obesity of castrated Ldlr(-/-) mice is independent of estrogens. Overall, our data reveal a novel role of Ldlr as functional modulator of metabolic alterations associated with hypogonadism.


Assuntos
Gorduras na Dieta/efeitos adversos , Hipogonadismo/metabolismo , Obesidade/metabolismo , Receptores de LDL/metabolismo , Testosterona/metabolismo , Animais , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Gorduras na Dieta/farmacologia , Hipogonadismo/induzido quimicamente , Hipogonadismo/genética , Hipogonadismo/patologia , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Masculino , Camundongos , Camundongos Knockout , Obesidade/induzido quimicamente , Obesidade/genética , Obesidade/patologia , Receptores de LDL/genética , Testosterona/genética , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
14.
J Sex Med ; 11(8): 1898-902, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24836599

RESUMO

INTRODUCTION: Three decades after the first nerve-sparing radical prostatectomy, postoperative erectile dysfunction (ED) remains a challenging and common problem. Despite considerable advances and improvements in surgical techniques, full recovery of erectile function remains elusive even for young, potent men. This suggests, ipso facto, that factors other than surgical technique must be important to recovery of erectile function. AIM: This study aims to review evidence that the prostate is an endocrine gland with contributions to local and systemic concentrations of 5α-dihydrotestosterone (5α-DHT), a potent androgen shown to be critical to penile physiology. METHODS: Literature review of human and animal studies related to endocrine role of prostate and postoperative recovery of erectile function. MAIN OUTCOME MEASURES: Effect of 5α-DHT on erectile function and recovery after surgical injury. RESULTS: We advance the following hypothesis: "Loss of endocrine function of the prostate, specifically reduced local 5α-DHT concentration plays a major role in the failure of full recovery of erectile function following anatomic nerve-sparing radical prostatectomy." CONCLUSIONS: We propose two separate, yet interrelated, mechanisms whereby the loss of 5α-DHT interferes with postoperative recovery of erectile function: (i) 5α-DHT contributes to cavernous nerve integrity and its ability to recover from surgical insult. (ii) 5α-DHT is important to the structural/functional integrity of penile tissues and erectile physiology. Kacker R, Morgentaler A, and Traish A. Medical hypothesis: Loss of the endocrine function of the prostate is important to the pathophysiology of postprostatectomy erectile dysfunction.


Assuntos
Di-Hidrotestosterona/metabolismo , Disfunção Erétil/etiologia , Complicações Pós-Operatórias/etiologia , Próstata/fisiopatologia , Prostatectomia/métodos , Androgênios/fisiologia , Animais , Disfunção Erétil/fisiopatologia , Humanos , Masculino , Tratamentos com Preservação do Órgão/efeitos adversos , Ereção Peniana/fisiologia , Pênis/inervação , Prostatectomia/efeitos adversos , Neoplasias da Próstata/fisiopatologia , Neoplasias da Próstata/cirurgia , Recuperação de Função Fisiológica/fisiologia
16.
Sex Med Rev ; 11(4): 384-394, 2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37587664

RESUMO

INTRODUCTION: Low testosterone (T) levels are associated with obesity, metabolic syndrome, type 2 diabetes mellitus and altered lipid profiles, thus contributing to increased cardiovascular disease risk. Hence T deficiency has a detrimental effect on men's vascular health, quality of life and increased mortality. OBJECTIVES: This review aims to present summary of data in the contemporary clinical literature pertaining to the benefits of T therapy in clinical studies with varying durations on vascular health in men with T deficiency. METHODS: A Medline search using PubMed and EMBASE was performed using the following key words: "testosterone deficiency," "testosterone therapy," major cardiovascular adverse events", "cardiovascular disease". Relevant studies were extracted, evaluated, and analyzed. We evaluated findings from clinical trials, observational studies and systematic reviews and meta-analyses to develop a comprehensive account of the critical role of T in maintaining vascular health. RESULTS: Considerable evidence beginning with studies published in 1940s concomitant with findings from the utmost recent clinical studies suggests a clinical value of T therapy in maintaining vascular health and reducing cardiovascular mortality. The current scientific and clinical evidence demonstrates strong relationship between low circulating T levels and risk of cardiovascular disease and T therapy is deemed safe in men with hypogonadism when given in the physiological range with no apparent harm. CONCLUSION: What emerges from the current clinical literature is that, irrespective of the length of study durations, testosterone therapy provides significant health benefits and reduces risk of cardiovascular disease. More important is that data from many observational and registry studies, demonstrated that longer durations of testosterone therapy were associated with greater health benefits and reduced cardiovascular risk. T therapy in men with T deficiency reduces the incidence of major adverse cardiovascular events attributed to improving overall metabolic function.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Hipogonadismo , Masculino , Humanos , Testosterona , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Qualidade de Vida , Hipogonadismo/complicações , Hipogonadismo/tratamento farmacológico
17.
J Sex Med ; 9(6): 1681-96, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22512993

RESUMO

INTRODUCTION: The role of estrogens in male sexual function and the pathogenesis of testosterone deficiency remain controversial and poorly understood. AIMS: To review the distribution of estrogens in normal and testosterone deficient men, their potential role in sexual function, and the clinical implications of elevated estrogens during testosterone therapy. METHODS: A comprehensive, broad-based literature review was conducted on the role of estrogens in male sexual function and testosterone deficiency. RESULTS: Estrogens elicit a variety of physiological responses in men and may contribute to modulation of sexual function. In the absence of testosterone deficiency, elevations in estrogens do not appear to be harmful and estrogens may help maintain some, but not all, sexual function in castrated men. While the therapeutic use of estrogens at pharmacologic doses has been used to suppress serum testosterone, naturally occurring elevations of estrogens do not appear to be a cause of low testosterone. During testosterone replacement, estrogens may rise and occasionally reach elevated levels. There is a lack of evidence that treatment of elevated estrogen levels during testosterone replacement has benefit in terms of male sexuality. CONCLUSION: Further research on the importance of estrogens in male sexual function is needed. Current evidence does not support a role of naturally occurring estrogen elevations in testosterone deficiency or the treatment of elevated estrogens during testosterone therapy.


Assuntos
Estrogênios/sangue , Disfunções Sexuais Fisiológicas/sangue , Sexualidade/fisiologia , Testosterona/deficiência , Testosterona/farmacologia , Inibidores da Aromatase/uso terapêutico , Moduladores de Receptor Estrogênico/uso terapêutico , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Hipogonadismo/sangue , Hipogonadismo/tratamento farmacológico , Masculino , Orquiectomia , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Testosterona/uso terapêutico
18.
Androg Clin Res Ther ; 3(1): 217-223, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36643964

RESUMO

There has been little recognition within the medical community of the health impact of testosterone (T) deficiency (TD), also known as hypogonadism, and the substantial benefits of testosterone therapy (TTh) on health and quality of life despite high-level clinical evidence. In a roundtable symposium, investigators summarized the contemporary evidence in several key clinical areas. TD negatively impacts human health and quality of life and is associated with increased mortality. Several studies have demonstrated that TTh in men with TD reduced all-cause and cardiovascular mortality. The longstanding belief that TTh is associated with increased prostate cancer (PCa) risk is contradicted by recent evidence, including multiple studies showing that TTh is associated with reduced PCa risk. Similarly, the weight of current evidence indicates the purported concern that TTh is associated with increased cardiovascular risk is incorrect. Normalization of physiological T reduces myocardial infarction, stroke, and deaths compared with men whose testosterone levels failed to normalize. In diabetic men TTh improves insulin resistance, and a large 2-year controlled study in men with abnormal glucose tolerance showed a substantially reduced rate of diabetes among men treated with TTh compared with untreated controls. Long-term TTh in diabetic men resulted in progressive improvements in obesity and insulin requirements, including a substantial number who experienced complete remission of diabetes. Finally, TTh has been shown to reduce severe outcomes with Covid-19 infection. These lines of evidence argue strongly for the need for greater awareness in the medical community of the impact of TD on health, and of the health benefits of TTh.

19.
Biochem Cell Biol ; 89(4): 423-33, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21819346

RESUMO

The RNA-binding protein p54(nrb) is involved in many nuclear processes including transcription, RNA processing, and retention of hyperedited RNAs. In interphase cells, p54(nrb) localizes to the nucleoplasm and concentrates with protein partners in the paraspeckles via an interaction with the non-coding RNA Neat1. During mitosis, p54(nrb) becomes multiphosphorylated and the effects of this modification are not known. In the present study, we show that p54(nrb) phosphorylation does not affect the interactions with its protein partners but rather diminishes its general RNA-binding ability. Biochemical assays indicate that in vitro phosphorylation of a GST-p54(nrb) construct by CDK1 abolishes the interaction with 5' splice site RNA sequence. Site-directed mutagenesis shows that the threonine 15 residue, located N-terminal to the RRM tandem domains of p54(nrb), is involved in this inhibition. In vivo analysis reveals that Neat1 ncRNA co-immunoprecipitates with p54(nrb) in either interphase or mitotic cells, suggesting that p54(nrb)-Neat1 interaction is not modulated by phosphorylation. Accordingly, in vitro phosphorylated GST-p54(nrb) still interacts with PIR-1 RNA, a G-rich Neat1 sequence known to interact with p54(nrb). In vitro RNA binding assays show that CDK1-phosphorylation of a GST-p54(nrb) construct abolishes its interaction with homoribopolymers poly(A), poly(C), and poly(U) but not with poly(G). These data suggest that p54(nrb) interaction with RNA could be selectively modulated by phosphorylation during mitosis.


Assuntos
Mitose , Proteínas Associadas à Matriz Nuclear/metabolismo , Fatores de Transcrição de Octâmero/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA , Células HeLa , Humanos , Imunoprecipitação , Interfase , Complexos Multiproteicos/metabolismo , Fosforilação , Ligação Proteica , Transporte Proteico , Sítios de Splice de RNA , RNA não Traduzido/metabolismo
20.
J Sex Med ; 8(11): 2960-82; quiz 2983, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22032408

RESUMO

INTRODUCTION: The circulation of large amounts of dehydroepiandrosterone (DHEA) and its sulfated derivative (DHEA-S) suggests a physiological role in human physiology. In the central nervous system, DHEA is considered a neurosteroid with a wide range of functions. AIM: The goal of this review is to discuss metabolism, biochemical, and physiological mechanism of DHEA action and the potential role of DHEA in aging and in ameliorating a host of pathological conditions, associated with aging. METHODS: We examined preclinical and clinical data reported in various studies from the available literature concerning the effects of DHEA in normal and pathological conditions. MAIN OUTCOME MEASURES: Data reported in the literature were analyzed, reviewed, and discussed. RESULTS: DHEA mediates its action via multiple signaling pathways involving specific membrane receptors and via transformation into androgen and estrogen derivatives (e.g., androgens, estrogens, 7α and 7ß DHEA, and 7α and 7ß epiandrosterone derivatives) acting through their specific receptors. These pathways include: nitric oxide synthase activation, modulation of γ-amino butyric acid receptors, N-methyl D-aspartate, receptors sigma receptors (Sigma-1), differential expression of inflammatory factors, adhesion molecules and reactive oxygen species, among others. Clinical and epidemiological studies suggested that low DHEA levels might be associated with ischemic heart disease, endothelial dysfunction, atherosclerosis, bone loss, inflammatory diseases, and sexual dysfunction. Most importantly, no significant adverse or negative side effects of DHEA were reported in clinical studies of men and women. CONCLUSIONS: DHEA modulates endothelial function, reduces inflammation, improves insulin sensitivity, blood flow, cellular immunity, body composition, bone metabolism, sexual function, and physical strength in frailty and provides neuroprotection, improves cognitive function, and memory enhancement. DHEA possesses pleiotropic effects and reduced levels of DHEA and DHEA-S may be associated with a host of pathologies; however, the clinical efficacy of DHEA supplementation in ameliorating patho-physiological symptoms remains to be evaluated.


Assuntos
Desidroepiandrosterona/fisiologia , Envelhecimento/fisiologia , Animais , Composição Corporal/fisiologia , Osso e Ossos/metabolismo , Doenças Cardiovasculares/fisiopatologia , Desidroepiandrosterona/biossíntese , Desidroepiandrosterona/metabolismo , Sulfato de Desidroepiandrosterona/metabolismo , Depressão/fisiopatologia , Endotélio Vascular/fisiologia , Feminino , Humanos , Imunidade Celular/fisiologia , Inflamação/fisiopatologia , Masculino , Comportamento Sexual/fisiologia , Pele/metabolismo
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