Does testosterone have a role in erectile function?

New evidence for the effect of type 2 diabetes and glycemic traits on testosterone levels: a two-sample Mendelian randomization study

Objective

Type 2 diabetes mellitus (T2DM) is an endocrine-related disease with an increasing incidence worldwide. Male sexual dysfunction is common in diabetic patients. Therefore, we designed a Mendelian randomization (MR) study to investigate the association of type 2 diabetes and 3 glycemic traits with testosterone levels.

Methods

Uncorrelated single nucleotide polymorphisms (SNPs) associated with T2DM (N = 228), fasting insulin (N = 38), fasting glucose (N = 71), and HbA1c (N = 75) at the genome-wide significance were selected as instrument variables. Genetic associations with testosterone levels (total testosterone, TT, bioavailable testosterone, BT, and sex hormone-binding globulin, SHBG) were obtained from the UK Biobank studies and other large consortia. Two-sample MR analysis was used to minimize the bias caused by confounding factors and response causality. Multivariable MR analysis was performed using Body mass index (BMI), Triglycerides (TG), LDL cholesterol (LDL), and adiponectin to adjust for the effects of potential confounders.

Results

Type 2 diabetes mellitus was associated with the decrease of total testosterone (β: -0.021,95%CI: -0.032, -0.010, p<0.001) and sex hormone binding globulin (β: -0.048,95%CI: -0.065, -0.031, p<0.001). In males, total testosterone (β: 0.058, 95% CI: 0.088, 0.028, p < 0.001) decreased. In females, it was associated with an increase in bioavailable testosterone (β: 0.077,95%CI: 0.058,0.096, p<0.001). Each unit (pmol/L) increase in fasting insulin was associated with 0.283nmol/L decrease in sex hormone-binding globulin (95%CI: -0.464, -0.102, p=0.002) and 0.260nmol/L increase in bioavailable testosterone (95%CI: -0.464, -0.102, p= 0.002). In males, sex hormone binding globulin decreased by 0.507nmol/L (95%CI: -0.960, -0.054, p= 0.028) and bioavailable testosterone increased by 0.216nmol/L (95%CI: 0.087,0.344, p= 0.001). In females, sex hormone binding globulin decreased by 0.714 nmol/L (95%CI: -1.093, -0.335, p<0.001) and bioavailable testosterone increased by 0.467nmol/L (95%CI: 0.286,0.648, p<0.001). Each unit (%) increase in HbA1c was associated with 0.060nmol/L decrease in sex hormone-binding globulin (95%CI: -0.113, -0.007, p= 0.026). In males, total testosterone decreased by 0.171nmol/L (95%CI: -0.288, -0.053, p=0.005) and sex hormone binding globulin decreased by 0.206nmol/L (95%CI: -0.340, -0.072, p=0.003). Total testosterone increased by 0.122nmol/L (95%CI: 0.012,0.233, p=0.029) and bioavailable testosterone increased by 0.163nmol/L (95%CI: 0.042,0.285, p=0.008) in females.

Conclusions

Using MR Analysis, we found independent effects of type 2 diabetes, fasting insulin, and HbA1c on total testosterone and sex hormone-binding globulin after maximum exclusion of the effects of obesity, BMI, TG, LDL and Adiponectin.

Prostaglandins as a Topical Therapy for Erectile Dysfunction: A Comprehensive Review

INTRODUCTION

Erectile dysfunction (ED) is a substantial cause of dissatisfaction among many men. This discontentment has led to the emergence of various drug treatment options for this problem.

OBJECTIVES

Unfortunately, due to various interactions, contraindications, and side effects, systemic therapies such as phosphodiesterase-5 inhibitors (including sildenafil, tadalafil, vardenafil, avanafil, etc.) are not welcomed in many patients. These problems have led researchers to look for other ways to reduce these complications.

METHODS

This article holistically reviews the efficacy of topical prostaglandins and their role in treating ED. We sought to provide a comprehensive overview of recent findings on the current topic by using the extensive literature search to identify the latest scientific reports on the topic.

RESULTS

In this regard, topical and transdermal treatments can be suitable alternatives. In diverse studies, prostaglandins, remarkably PGE1 (also known as alprostadil), have been suggested to be an acceptable candidate for topical treatment.

CONCLUSION

Numerous formulations of PGE1 have been used to treat patients so far. Still, in general, with the evolution of classical formulation methods toward modern techniques (such as using nanocarriers and skin permeability enhancers), the probability of treatment success also increases.

Erectile dysfunction and sexual quality of life in patients who underwent low-dose-rate brachytherapy alone for prostate cancer

This study evaluated erectile function and sexual quality of life (QoL), and predictive factors for erectile dysfunction (ED) and the deterioration of sexual QoL in 70 patients who underwent low-dose-rate brachytherapy (LDR-BT) alone for prostate cancer without androgen deprivation therapy. Erectile function and sexual QoL were evaluated before and 1, 3, 6, 12, 24, 36, 48 and 60 months after LDR-BT. Binary logistic regression analysis was used to determine whether age, prostate volume, hypertension, diabetes, Brinkman's index, testosterone, baseline Sexual Health Inventory for Men (SHIM) score and post-implant dosimetry parameters could predict ED and deterioration of sexual QoL at 24 and 60 months after LDR-BT. After 24 and 60 months, ED was noted in 39 of 70 patients and 42 of 64 patients respectively. Furthermore, sexual QoL worsened in 42 of 70 and 43 of 64 patients respectively. Baseline SHIM score was identified as a significant predictor of ED (24 months: odds ratio [OR]: 0.83, p = 0.02; 60 months: OR: 0.83, p = 0.03) and the deterioration of sexual QoL (24 months: OR: 0.84, p = 0.03). LDR-BT for prostate cancer promoted decreased erectile function and sexual QoL, with high preimplant potency being a significant predictor of ED and the deterioration of sexual QoL.

Estradiol is an independent risk factor for organic erectile dysfunction in eugonadal young men

Erectile dysfunction attributable to testosterone deficiency is less common in young males, and the effect of estradiol on erectile function in eugonadal young males is unclear. We analyzed data from 195 male participants, including 143 eugonadal patients with erectile dysfunction and 52 healthy men. To distinguish psychogenic and organic erectile dysfunction, penile rigidity was measured using the nocturnal penile tumescence rigidity test. Serum levels of sexual hormones were quantified by electrochemiluminescence, and penile vascular status was assessed by penile color Doppler ultrasound. Both serum estradiol levels and the ratio of estradiol to testosterone were higher in patients with organic erectile dysfunction than in patients with psychogenic erectile dysfunction or healthy controls. Organic erectile dysfunction was negatively associated with estradiol levels and the ratio of estradiol to testosterone, and estradiol was the only significant risk factor for organic erectile dysfunction (odds ratio: 1.094; 95% confidence interval: 1.042–1.149, P = 0.000). Moreover, serum estradiol levels were negatively correlated with penile rigidity. Serum estradiol levels were higher and penile rigidity was lower in patients with venous erectile dysfunction than in patients with nonvascular erectile dysfunction. We conclude that elevated serum estradiol levels may impair erectile function and may be involved in the pathogenesis of organic erectile dysfunction in eugonadal young men.

Aetiological analysis and diagnosis of reproductive disorders in male dromedary camels

The purpose of this paper was to analyse the aetiology and methods of diagnosing reproductive disorders in male dromedary camels. Male camel infertility manifests as one of three conditions: post-coital infertility (IG), inability to copulate (IC) and lack of sexual desire (LSD). IG is mainly a testicular disorder that is linked to a deteriorated seminogram, arrested spermatogenesis, Sertoli cell-only syndrome and testicular degeneration. For IG diagnosis, semen analysis, testicular biopsy and fine-needle aspiration are gold standards. Testicular ultrasonography was generally inefficient. High serum FSH was found in IG camels with oligo- and azoospermia, implying primary spermatogenesis defects. The testis-expressed protein (TEX101) and the epididymis-expressed protein (ECM1) are reliable biomarkers for distinguishing between obstructive and non-obstructive azoospermia. IC manifests in two forms: phimosis (PHI) and erectile dysfunction (ED). PHI is frequently linked to preputial and penile pathologies, as well as leucocytosis, neutrophilia and elevated nitric oxide metabolites. The majority of camels with ED have normal genital organs, and the condition is associated with an increase in cardiac troponin I. LSD is a rare disorder brought on by hormonal imbalances, high temperatures, stress and debilitating diseases. In conclusion, IG diagnosis necessitates semen analysis, testicular biopsy or fine-needle aspiration, and FSH testing, whereas IC diagnosis requires preputial and penile examinations. Diagnostic aids include serum and seminal biomarkers.

Neurobehavioral, testicular and erectile impairments of chronic ketamine administration: Pathogenesis and ameliorating effect of N-acetyl cysteine

Ketamine, a dissociative anesthetic, recently has spread as a recreational drug. Its abuse lead to neurobehavioral disturbance in addition to toxic effects on other body organs. To evaluate the toxic effects of chronic administration of low ketamine doses on the memory, testicles, and erection, explore its pathophysiology through oxidative stress mechanism and examine the ameliorating effect of N-acetyl cysteine (NAC). A total of 40 male albino rats were assigned to control, vehicle, ketamine only I.P. (10 mg/kg), and ketamine (10 mg/kg) + NAC (150 mg/kg) groups. Assessment of memory affection and erectile function by Passive Avoidance, Novel Object Recognition, and copulatory tests were performed. Estimation of malondialdehyde (MDA), catalase (CAT), and total antioxidant capacity (TAC) in serum and prefrontal & hippocampal homogenate, and luteinizing hormone (LH), testosterone in serum were done. Prefrontal cortex, hippocampus, and testes were collected for histopathology. Chronic ketamine administration induced significant memory deficits (P < 0.05), reduced erectile function (P < 0.05), severe hypospermatogenesis, increased MDA, reduced CAT, TAC levels in serum, and tissue homogenate (P < 0.05) and reduction of LH, and testosterone (P < 0.05). Treatment with NAC resulted in significant improvement of memory function, improved erectile function, and decrease in oxidative injury in both serum and tissue homogenates. Testosterone and LH levels exhibited significant difference between treatment groups and controls (P < 0.05). NAC reduced the deleterious histopathological changes. These data suggest that long-term ketamine affects short and long memory, induces erectile and testicular dysfunction through oxidative stress. Co-administration with NAC ameliorates these toxic effects.

Sexual dysfunction among diabetics and its impact on the SQoL of their partners

Sexual dysfunction (SD) has long been known to affect a significant number of people worldwide with serious implications and limitations on sexual expression and fulfillment. This may affect the sexual quality of life (SQoL) of individuals and their partners. A cross-sectional study was conducted among diabetic patients and their partners who visited the Tema General Hospital. A total of 130 and 116 diabetic males and females and their partners were interviewed. Male and female diabetic participants and partners were evaluated using the Golombuk Rust Inventory for Sexual Satisfaction-Male (GRISS-M)/SQoL-M and GRISS-Female/SQoL-F, respectively. For the diabetic males, the mean age and duration of diabetes (DOD) was 63.04±10.85 and 8.38±6.53 years, respectively, and that of the diabetic females was 56.98±9.42 and 6.11±5.31 years, respectively. Diabetic male participants with SD were significantly older and had a longer duration of diabetes. The mean SQoL and SQoL-Partner (SQoL-P) recorded for the diabetic males and their partners was 42.29±30.88 and 52.86±15.26, respectively. The mean SQoL and SQoL-P recorded for the diabetic females and their partners was 57.73±14.91 and 64.97±19.68, respectively. Diabetic males who had impotence had female partners with significantly lower SQoL-P scores, and similar results were recorded for those who had premature ejaculation, nonsensuality, avoidance and dissatisfaction problems. Female diabetics who had nonsensuality, avoidance and infrequency had male partners who recorded significantly lower SQoL-P scores. Female diabetics with higher perceptions of what an adequate intravaginal ejaculatory latency time (IELT) should be had male partners with significantly lower SQoL-P scores. Ageing and DOD are more likely to affect the sexual functioning of diabetic males than females. SD in diabetics with problems of impotence/vaginismus, premature ejaculation/anorgasmia, nonsensuality and avoidance has an adverse effect on the SQoL-P of their partners. Male partners of diabetic females who have a higher perception of IELT had a reduced SQoL. Ageing and longer DOD in diabetics are associated with a reduced SQoL-P of their partners.

Translational Perspective on the Role of Testosterone in Sexual Function and Dysfunction

INTRODUCTION

The biological importance of testosterone is generally accepted by the medical community; however, controversy focuses on its relevance to sexual function and the sexual response, and our understanding of the extent of its role in this area is evolving.

AIM

To provide scientific evidence examining the role of testosterone at the cellular and molecular levels as it pertains to normal erectile physiology and the development of erectile dysfunction and to assist in guiding successful therapeutic interventions for androgen-dependent sexual dysfunction.

METHODS

In this White Paper, the Basic Science Committee of the Sexual Medicine Society of North America assessed the current basic science literature examining the role of testosterone in sexual function and dysfunction.

RESULTS

Testosterone plays an important role in sexual function through multiple processes: physiologic (stimulates activity of nitric oxide synthase), developmental (establishes and maintains the structural and functional integrity of the penis), neural (development, maintenance, function, and plasticity of the cavernous nerve and pelvic ganglia), therapeutically for dysfunctional regulation (beneficial effect on aging, diabetes, and prostatectomy), and phosphodiesterase type 5 inhibition (testosterone supplement to counteract phosphodiesterase type 5 inhibitor resistance).

CONCLUSION

Despite controversies concerning testosterone with regard to sexual function, basic science studies provide incontrovertible evidence for a significant role of testosterone in sexual function and suggest that properly administered testosterone therapy is potentially advantageous for treating male sexual dysfunction.

Relationship between Erectile Dysfunction, Comorbidity, and Parkinson's Disease: Evidence from a Population-Based Longitudinal Study

BACKGROUND AND PURPOSE

To determine the risk of Parkinson's disease (PD) in relation to erectile dysfunction (ED) based on the National Health Insurance Research Database in Taiwan.

METHODS

We identified 3,153 patients who were newly diagnosed with ED between January 1, 2004 and December 31, 2010. A total of 12,612 randomly selected people without ED served as healthy controls. All of the study subjects were followed-up from the index date to the date of PD diagnosis, withdrawal from the National Health Insurance program, or the end of 2012 whichever occurred first.

RESULTS

The incidence density rate of PD was 1.52-fold higher in the ED cohort than the non-ED cohort (3.44 vs. 1.64 per 1,000 person-years), with an adjusted hazard ratio (HR) of 1.52 [95% confidence interval (CI)=1.09-2.12]. The combined effects on patients with ED and diabetes as well as hypertension showed a significant combined association with the PD risk compared with patients without ED, counterpart comorbidities, or medication use. The adjusted HR of PD for ED was higher for diabetes (2.82, 95% CI=1.42-5.63) and hypertension (2.19, 95% CI = 1.35-3.55).

CONCLUSIONS

ED leads to an increased risk of PD. ED patients with diabetes or hypertension have an elevated risk of PD.

Erectile dysfunction is a prognostic indicator of comorbidities in men with late onset hypogonadism

INTRODUCTION

The role of testosterone deficiency in erectile dysfunction (ED) is increasingly recognized; however, there is a need to clarify the nature of the relationship between ED and late onset hypogonadism (LOH).

AIM

In this study, we sought to determine the correlators of ED severity amongst men with LOH.

METHODS

130 patients diagnosed with LOH fulfilling the criteria of total testosterone ≤3.5 ng/ml (<12 nmol/l) and with an erectile function domain score <21 on the International Index of Erectile Function questionnaire (IIEF questions 1-5) were enrolled for a subsequent trial of Testosterone Undecanoate. Demographic data were recorded at baseline.

MAIN OUTCOME MEASURES

Subjects completed three standardised questionnaires to assess sexual health including International Prostate Symptom Score (IPSS), Aging Males Symptoms (AMS) and IIEF Sexual Health Inventory for Men (SHIM). Patients were stratified by ED severity with SHIM scores of 1-7 considered severe ED, 8-11 moderate ED and 12-16 mild to moderate. Serum testosterone, sex hormone binding globulin (SHBG) and lipids (total cholesterol, triglycerides, high-density lipoprotein and low-density lipoprotein) were assessed along with plasma fasting glucose and HbA1c. Weight, BMI and waist circumference were also recorded.

RESULTS

A significant association was observed between severity of ED and mean weight (p = 0.000), waist circumference (p = 0.000), triglycerides (p = 0.009), total cholesterol (p = 0.027), HbA1c (p = 0.000), fasting glucose (p = 0.003) and AMS scores (p = 0.043). No significant differences were seen in testosterone fractions and SHBG levels between ED subgroups. A positive correlation existed between the prevalence of diabetes mellitus (type 1 and type 2) and ED severity in this cohort (p = 0.018).

CONCLUSIONS

The descriptive data of our cohort show that increased severity of ED within LOH patients correlated with an increased waist circumference, hyperglycemia, hypertriglyceridemia, hyperlipidemia and a history of diabetes mellitus. Severe ED functions as a prognostic indicator of co-morbidities in men with LOH.

Late-onset hypogonadism: current concepts and controversies of pathogenesis, diagnosis and treatment

Although suppressed serum testosterone (T) is common in ageing men, only a small proportion of them develop the genuine syndrome of low T associated with diffuse sexual (e.g., erectile dysfunction), physical (e.g. loss of vigor and frailty) and psychological (e.g., depression) symptoms. This syndrome carries many names, including male menopause or climacterium, andropause and partial androgen deficiency of the ageing male (PADAM). Late-onset hypogonadism (LOH) describes it best and is therefore generally preferred. The decrease of T in LOH is often marginal, and hypogonadism can be either due to primary testicular failure (low T, high luteinizing hormone (LH)) or secondary to a hypothalamic-pituitary failure (low T, low or inappropriately normal LH). The latter form is more common and it is usually associated with overweight/obesity or chronic diseases (e.g., type 2 diabetes mellitus, the metabolic syndrome, cardiovascular and chronic obstructive pulmonary disease, and frailty). A problem with the diagnosis of LOH is that often the symptoms (in 20%–40% of unselected men) and low circulating T (in 20% of men >70 years of age) do not coincide in the same individual. The European Male Ageing Study (EMAS) has recently defined the strict diagnostic criteria for LOH to include the simultaneous presence of reproducibly low serum T (total T <11 nmol l⁻¹ and free T <220 pmol l⁻¹) and three sexual symptoms (erectile dysfunction, and reduced frequency of sexual thoughts and morning erections). By these criteria, only 2% of 40- to 80-year-old men have LOH. In particular obesity, but also impaired general health, are more common causes of low T than chronological age per se. Evidence-based information whether, and how, LOH should be treated is sparse. The most logical approach is lifestyle modification, weight reduction and good treatment of comorbid diseases. T replacement is widely used for the treatment, but evidence-based information about its real benefits and short- and long-term risks, is not yet available. In this review, we will summarize the current concepts and controversies in the pathogenesis, diagnosis and treatment of LOH.

Treatment strategies for diabetic patients suffering from erectile dysfunction: an update

INTRODUCTION

Erectile dysfunction (ED) is one of the most common complications of diabetes. The complex pathophysiology of this disease makes it difficult to create clinical treatments tailored specifically for diabetic patients.

AREAS COVERED

This article will provide an update of both medical and surgical treatment approaches for diabetic ED, as well as discuss established treatments that are the cornerstone of this field.

EXPERT OPINION

Currently, PDE type 5 inhibitors represent the first-line treatment for all patients with ED. In the interim since this article's first publication several new PDE5 inhibitors have come to market. Several others that were previously on the market are now available for daily dosing. Analysis of both testosterone level and hemoglobin A1c is an essential part of treatment. Intracavernosal injections and vacuum constriction devices remain safe, and are highly effective treatment options. The implantable penile prosthesis remains a safe, and definitive treatment modality for those patients with refractory ED. Over the coming years as the understanding of the underlying causes of diabetic ED continues, the development of new, noninvasive, but effective medical treatments will lead to even more options for the treatment of this difficult disease.

Asexuality development among middle aged and older men

Objectives

To assess erectile function in middle-aged and older men with asexuality status and further analyze their specific reasons for this condition.

Subjects and Methods

Men who had regular sexual intercourse attempts (sex frequency≥1 time per month) were classified into mild erectile dysfunction (ED), moderate to severe ED and non-ED according to International Index of Erectile Function-5, and men having no sexual intercourse attempts for at least 6 months were defined as having an asexuality status. The risk factors associated with ED were collected in a sample of 1,531 Chinese men aged 40 to 80 years, and the self-report reasons for asexuality were recorded in asexual cohort individually. Comparative analyses and multivariate regression models were conducted among these groups.

Results

The prevalence rates of ED and asexuality status were 49.9% and 37.2%. The asexuality status group had higher risk factors than the moderate to severe ED group in terms of old age (age≥65, adjusted odds ratio (OR) 17.69 versus (Vs.) 7.19), diabetes (crude OR: 2.40 Vs. 2.36) and hypertension (crude OR: 1.78 Vs. 1.72). The specific reasons for the asexuality status were “erectile difficulty” (52.9%), “do not care about sexuality” (53.5%)”, “no longer necessary to have sexuality at this age” (47.7%), “severe stress” (44.4%), “severe fatigue” (26.3%) and “masturbation” (26.9%).

Conclusions

Men with an asexual status suffer from higher risk factors for ED than men with moderate to severe ED. The majority of this asexual status could be attributed to a full ED, although the reasons for this transient asexuality also involved sexual attitudes and interests, sexual partners and masturbation.

Combined testosterone and vardenafil treatment for restoring erectile function in hypogonadal patients who failed to respond to testosterone therapy alone

INTRODUCTION

The role of testosterone in erectile dysfunction (ED) is increasingly recognized. It is suggested that assessment of testosterone deficiency in men with ED and symptoms of hypogonadism, prior to first-line treatment, may be a useful tool for improving therapy.

AIM

In this prospective, observational, and longitudinal study, we investigated the effects of vardenafil treatment as adjunctive therapy to testosterone undecanoate in hypogonadal ED patients who failed to respond to testosterone treatment alone.

METHODS

One hundred twenty-nine testosterone deficient (serum total testosterone ≤ 3.4 ng/mL) patients aged 56 ± 3.9 years received intramuscular injections of long-acting parenteral testosterone undecanoate at 3-month intervals for 8 months mean follow-up.

MAIN OUTCOME MEASURES

Scores on the International Index of Erectile Function Questionnaire-five items (IIEF-5) and partner survey scores were compared at baseline and posttreatment with testosterone therapy alone or in combination with vardenafil. Patient baseline demographics and concomitant disease were correlated with patients' IIEF-5 scores.

RESULTS

Seventy one (58.2%) responded well to monotherapy within 3 months. Nonresponders had lower testosterone levels and higher rates of concomitant diseases and smoking. Thirty-four of the 51 nonresponders accepted the addition of 20 mg vardenafil on demand. Efficacy assessments were measured by the IIEF-erectile function domain (IIEF-EF, questions 1-5 plus 15, 30 points) and partner self-designed survey at baseline after 4-6 weeks and at study end point. Thirty out of 34 patients responded well to this combination. IIEF-EF Sexual Health Inventory for Men score improved from 12 to 24 (P < 0.0001), and partner survey showed significantly higher satisfaction (P < 0.001). These patients reported spontaneous or nocturnal and morning erections or tumescence. No changes in adverse effects were recorded.

CONCLUSIONS

These data suggest that combination therapy of testosterone and vardenafil is safe and effective in treating hypogonadal ED patients who failed to respond to testosterone monotherapy.

Treatment of clozapine-induced priapism by goserline acetate injection

Clozapine (Denzapine) is a treatment for resistant schizophrenia. Among the serious but rare side effects of clozapine are agranulocytosis and priapism. We hereby present the case of a 30-year-old man with a diagnosis of schizophrenia who has spent nearly 12 years of his adult life on various psychiatric in-patient units including open wards, secure units, psychiatric intensive care units and rehab wards. Diagnosed at the age of 15, he only responded to clozapine at the age of 18. Whilst being on clozapine he developed priapism in June 2010 and needed emergency surgical treatment in the form of surgical decompression. He again responded only to clozapine and fortunately he did not redevelop priapism; however, he was readmitted in February 2011 due to relapse, and he remained resistant to other antipsychotics. He was rechallenged with clozapine and recovered, but unfortunately redeveloped priapism which required emergency surgical and medical intervention (goserline acetate and tinzaperin injection). In order to relieve the recurrent priapism, he agreed to continue clozapine and goserline acetate injection. This decision was made by the patient in a compos mentis state. As far as we are aware, this is the first time goserline acetate has been reported as a successful treatment for clozapine-induced priapism.

The high prevalence of testosterone deficiency in population of Polish men over 65 years with erectile dysfunctions

OBJECTIVES

Erectile dysfunctions (EDs) are in part caused by hormonal causes; but in men over 65 years of age, testosterone deficiency seems to play an important role. However, in population of Polish men over 65 years of age with relative poor health status, the prevalence of testosterone deficiency in patients with ED is unknown.

MATERIAL AND METHODS

286 men over 65 years of age with EDs were invited to complete an erectile function questionnaire (IIEF-5), as a diagnostic tool for EDs. Serum total testosterone (TT) levels were measured. Linear regression model was used to analyze the factors that are associated with testosterone deficiency.

RESULTS

The prevalence of testosterone deficiency was 17, 33, 42 and 57% for testosterone levels of less than 200, 250, 300 and 350 ng/dL, respectively. Only 47% patients had testosterone levels in the normal range (>350 ng/dL). The degree of ED was significantly higher in men with lowest testosterone levels (p < 0,002), and it was mild in 39.5% of cases, mild-to-moderate in 26.2%, moderate in 18.2% and severe in 16%. There was significant inverse relationship between age and TT (r = -0.3328, p < 0.05), IIEF-5 score and TT (r = -0.3149, p < 0.05) and IIEF-5 score and age (r = -0.3463, p < 0.05). The most common metabolic disorders were: obesity (68% in men with TT levels >350 ng/dL and 91% in men with TT levels <350 ng/dL) and dyslipidemia (54 and 95%, respectively). Obesity, age and hyperlipidemia all correlated with significantly decreased testosterone levels. Impaired fasting glucose did not affect the testosterone levels.

CONCLUSIONS

Testosterone deficiency was very common in population of Polish men presenting with EDs and correlated negatively with age, obesity and dyslipidemia. These results can be associated with relative poor health status of Polish population.

Effect of testosterone and frequent low-dose sildenafil/tadalafil on cavernous tissue oxidative stress of aged diabetic rats

This study aimed to assess the effect of testosterone (T) administration and chronic low-dose sildenafil/tadalafil on cavernous tissue oxidative stress (OS) of aged diabetic rats. In all, 140 Sprague-Dawley aged rats were subdivided into the following: controls; streptozotocin (STZ)-induced diabetic rats; diabetic rats injected with T every 4 weeks; diabetic rats on sildenafil orally daily; diabetic rats on T and daily sildenafil; diabetic rats on tadalafil orally every other day; diabetic rats on T and tadalafil; diabetic rats on alternate sildenafil/tadalafil; and diabetic rats on alternate sildenafil/tadalafil with T. After 12 weeks, the rats were euthanised where in dissected cavernous tissues malondialdehyde (MAD), glutathione peroxidase (GPx) and cGMP (cyclic guanosine monophosphate) were estimated. Compared with controls, aged diabetic rats demonstrated significant increase in cavernous tissue MDA and significant decrease in GPx and cGMP where diabetic rats injected with T had marked improvement of these parameters. Diabetic rats on sildenafil, tadalafil or alternate sildenafil/tadalafil demonstrated significant increased cavernous tissue GPx, cGMP and decreased cavernous MDA that was further improved when supplemented with T. It is concluded that frequent low-dose use of sildenafil and/or tadalafil supplemented with T has a marked impact on ameliorating cavernous OS in aged diabetic rats.

Multiple sclerosis and sexual dysfunction

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disorder of the central nervous system characterized by episodic and progressive neurologic dysfunction resulting from inflammatory and autoimmune reactions. The underlying pathogenesis of MS remains largely unclear. However, it is currently accepted as a T cell-mediated autoimmune disease. Among other clinical manifestations, sexual dysfunction (SD) is a painful but still underreported and underdiagnosed symptom of the disorder. SD in MS patients may result from a complex set of conditions and may be associated with multiple anatomic, physiologic, biologic, medical and psychological factors. SD arises primarily from lesions affecting the neural pathways involved in physiologic function. In addition, psychological factors, the side effects of medications and physical symptoms such as fatigue, muscular weakness, menstrual changes, pain and concerns about bladder and bowel incontinence may also be involved. Since MS primarily affects young people, SD secondary to MS may have a great impact on quality of life. Thus, maintaining a healthy sexual life with MS is an important priority. The treatment of SD requires multidisciplinary teamwork and cooperation among specialists, individual patients, partners and the society.

Biochemical and genetic markers of erectile dysfunction

Erectile dysfunction (ED) is a very common pathology, affecting over 150 million men worldwide. The pathogenesis is typically multifactorial, involving a kaleidoscope of organic, endocrine, and psychogenic factors. In general, ED is divided into organic and psychogenic impotence, but most men with organic etiologies have an associated psychogenic component. Given the high frequency of this pathology, the identification of biochemical and genetic correlates and/or markers is of pivotal interest not only for treating preciously these patients and preventing serious psychological consequences but also for the high risk for occult cardiovascular disease (CVD) that often accompanies or follows this pathology. A variety of cardiovascular risk factors have been associated with both the onset and the severity of ED, including markers of endothelial function, thrombosis, and especially dyslipidemia, so that their measurement should now be considered as an important part of the increased global cardiometabolic risk profile in patients with ED. While nitric oxide (NO), asymmetric dimethylarginine (ADMA), and endothelin (ET) hold some promises as biochemical markers of both CVD and ED, there are several technical and clinical drawbacks that make their measurement overall meaningless in the clinical practice. As regards genetic polymorphisms, controversial results have been provided so far. Although some genetic markers were consistently associated with ED, other studies failed to demonstrate significant associations, highlighting a substantial bias in standardization of methodologies and patient enrolment. Nevertheless, further research in this area should be encouraged, since the first promising evidence that gene therapy might be effective to restore the decline in ED has been provided in the animal model.

Original immunophenotype of blood endothelial progenitor cells and microparticles in patients with isolated arterial erectile dysfunction and late onset hypogonadism: effects of androgen replacement therapy

OBJECTIVE

Blood endothelial progenitor cells (EPCs) and endothelial microparticles (EMPs) have been proposed as markers of endothelial dysfunction. Aim of this study was to evaluate an original immunophenotype of EPCs and EMPs in patients with isolated arterial erectile dysfunction (ED) and late onset hypogonadism (LOH) before and after androgen replacement therapy.

MATERIALS AND METHODS

Fifty patients (50-64 years) with ED and LOH were selected. EPC (CD45(neg)/CD34(pos)/CD144(pos)) and EMP (CD45(neg)/CD34(neg)/CD144(pos)) blood concentrations were evaluated by flow cytometry. Thirty patients received androgen replacement therapy (Tostrex® ProStrakan) for 6 months (group A), other 20 patients not received androgen therapy for the contraindications in their clinical history (group B).

RESULTS

After 6 months, group B showed IIEF-5 score, peak systolic velocity and acceleration time significantly worse than group A; in addition EPCs and EMPs were significantly higher in group B compared to group A.

CONCLUSIONS

Patients with isolated arterial ED and LOH not treated with androgen therapy showed worst vascular parameters measured by penile Doppler and higher EPCs and EMPs compared to treated hypogonadal patients, hence, LOH appears to be an additional vascular risk factor, and these markers may be considered as predictors of cavernous artery disease. Finally, androgen therapy improves endothelial dysfunction.

Markers of erectile dysfunction

With the development and marketing of oral pharmacotherapy that is both noninvasive and successful in treating erectile dysfunction (ED), the quest to identify markers of organic ED lost ground. Indeed, the multi-factorial nature of ED may have led many researchers to conclude that searching for a universal marker of ED was futile. However, the realization that ED is strongly correlated with the overall health of men, and may act as a predictor for the development of cardiovascular disease (CVD) and diabetes, has stimulated interest in identifying genes that can distinguish organic ED. In addition, the potential ability to suggest to the patient that ED is reversible (i.e., psychogenic) with a simple test would be of significance to both the physician and patient, as well as for reimbursement issues for therapy by insurance companies. Such a marker may also act as a non-subjective measure of the degree of ED and the efficacy of treatment. This review discusses the importance of identifying such markers and recent work identifying potential markers in human patients.

Male late-onset hypogonadism: pathogenesis, diagnosis and treatment

Some aging men develop a condition of suppressed serum testosterone levels, which is associated with diffuse sexual, physical and psychological symptoms. Several terms are used for this syndrome, but late-onset hypogonadism (LOH) is preferred. The diagnosis of LOH is often uncertain because symptoms (occurring in 20-40% of men) and low circulating testosterone (found in 20% of men >70 years of age) seldom occur together. The strict diagnostic criteria for LOH include reproducibly low serum testosterone levels and sexual symptoms, including erectile dysfunction and reduced frequency of sexual thoughts and morning erections. Using these diagnostic criteria, only 2% of 40-80-year-old men have LOH. Obesity and impaired general health (including diabetes mellitus, cardiovascular and chronic obstructive pulmonary disease, and frailty) are more common reasons for low testosterone than advanced age per se. It seems logical, therefore, to begin by treating these conditions before testosterone replacement therapy is initiated. Even then, testosterone should only be used if there are no contraindications, such as unstable cardiac disease, serious prostate symptoms and high hemoglobin level. The long-term benefit of testosterone replacement therapy is uncertain, and the experimental nature of the treatment, and its associated risks, must be fully explained to the patient before treatment begins.

Erectile dysfunction in opioid users: lack of association with serum testosterone

This study describes the prevalence of erectile dysfunction (ED) among 57 men using illicit opioids who presented to a primary care program for buprenorphine therapy. Participants' mean age was 40 years and 34% reported ED. Low total testosterone was detected in 17% of those reporting ED, but total testosterone was not significantly associated with ED. Examining multiple comorbidities and laboratory parameters, only older age was significantly associated with ED (r = .27, P< .05). ED is highly prevalent among men abusing opioids, but low total testosterone is rarely the cause.

Quality of life, self-esteem, fatigue, and sexual function in young men after cancer: a controlled cross-sectional study

BACKGROUND

Androgen deficiency is increasingly recognized in young male cancer survivors; however, its impact on quality of life (QOL) is not established. The authors investigated the relationship between androgen levels, QOL, self-esteem, fatigue, and sexual function in young male cancer survivors compared with control subjects.

METHODS

A cross-sectional, observational study of 176 male cancer survivors and 213 male controls aged 25 to 45 years was performed. Subjects completed 3 QOL scales (Medical Outcomes Study 36-Item Short-Form Health Survey version 2, the 12-item General Health Questionnaire [GHQ-12], and Aging Male Scale), and measures of self-esteem (Rosenberg Self-Esteem Scale), fatigue (Functional Assessment of Chronic Illness Therapy-Fatigue), and sexual function (Derogatis Interview for Sexual Functioning-II Self-Report-Male).

RESULTS

Cancer survivors had lower scores for all components of the Short-Form Health Survey, Aging Male Scale, and Functional Assessment of Chronic Illness Therapy-Fatigue, and for 4 of 5 subsections of the Derogatis Interview for Sexual Functioning than controls. The majority of these differences remained after adjusting by linear regression analysis. Levels of psychiatric disorder or self-esteem did not differ between the 2 groups. In cancer survivors, those with androgen deficiency (serum testosterone < or = 10 nmol/L) had lower scores than those without for all components of the Short-Form Health Survey, the General Health Questionnaire, Functional Assessment of Chronic Illness Therapy-Fatigue, and the Derogatis Interview for Sexual Functioning. Serum testosterone only weakly correlated with health measures.

CONCLUSIONS

Young male cancer survivors self-report a marked impairment in QOL, energy levels, and quality of sexual functioning, and this was exacerbated in those with androgen deficiency. However, psychological distress was not elevated, self-esteem was normal, and sexual relationships were not impaired. The relationship with testosterone is complex, and appears dependent on a threshold level rather than direct correlation. Interventional trials are needed to determine whether testosterone replacement would improve QOL in young male cancer survivors.

Influence of serum testosterone on urinary continence and sexual activity in patients undergoing radical prostatectomy for clinically localized prostate cancer

The aim of the present study was to evaluate how serum testosterone level (T) can affect urinary continence and erectile function in patients undergoing radical prostatectomy (RP). We included 257 patients with clinically localized prostate cancer, those who had filled out preoperative quality of life questionnaires (University of California, Los Angeles Prostate Cancer Index, International Index of Erectile Function (IIEF)), and those who had T and total PSA sampled the day before surgery. We calculated correlations between T and age, body mass index (BMI), PSA, urinary function or bother (UF, UB) and sexual function or bother (SF, SB) and IIEF-5 in the whole population and in sub-populations with normal (⩾10.4 nmol l⁻¹) and low (<10.4 ng ml⁻¹) T using Pearson's and Spearman's correlation coefficients. We evaluated differences in these parameters between patients with low and normal T using the unpaired samples t-test and Mann–Whitney test, and finally the correlation between UF and SF, UB and SB, and between PSA and T in the overall population, and separately in patients with low and normal T using the Pearson's correlation coefficient. Mean preoperative T was 13.5 nmol l⁻¹ and 23.7% of patients presented a low T. Mean age, mean BMI and mean preoperative total PSA at RP were 64.3 years, 25.9 kg m⁻² and 9.0 ng ml⁻¹, respectively. BMI was negatively correlated with T in the overall population (r=−0.266; P=0.02); moreover, patients with normal T presented lower BMI compared with patients with low T (25.7 vs 27.6: P=0.02). We found a significant correlation between SF scores and T in patients with normal T (r=0.1777: P=0.05). SF was significantly higher in patients with normal T compared with those with low T (74.8 vs 64.8: P=0.05). Furthermore, UF and UB were significantly correlated with SF (r=0.2544: P<0.01) and SB (r=0.2512: P=0.01), respectively, in men with normal T. Serum T was significantly correlated with PSA in men with low T (r=0.3874: P=0.0029), whereas this correlation was missed in the whole population and in men with normal T. The correlation between preoperative PSA and T in men with low T is in agreement with the ‘saturation' model proposed by Morgentaler. The correlation between basal T and preoperative erectile function and urinary continence underlines the importance of assessing T before RP.

Oxytocin, vasopressin, prostaglandin F(2alpha), luteinizing hormone, testosterone, estrone sulfate, and cortisol plasma concentrations after sexual stimulation in stallions

This experiment was designed to determine the effects of sexual stimulation on plasma concentrations of oxytocin (OT), vasopressin (VP), 15-ketodihydro-PGF(2alpha) (PG-metabolite), luteinizing hormone (LH), testosterone (T), estrone sulfate (ES), and cortisol (C) in stallions. Semen samples were collected from 14 light horse stallions (Equus caballus) of proven fertility using a Missouri model artificial vagina. Blood samples were collected at 15, 12, 9, 6, and 3 min before estrous mare exposure, at erection, at ejaculation, and at 3, 6, and 9 min after ejaculation. Afterwards, blood sampling was performed every 10 min for the following 60 min. Sexual activity determined an increase in plasma concentrations of OT, VP, C, PG-metabolite, and ES and caused no changes in LH and T concentrations. The finding of a negative correlation between C and VP at erection, and between C and T before erection and at the time of erection, could be explained by a possible inhibitory role exerted by C in the mechanism of sexual arousal described for men.

Down-regulation of murine testicular 17β-HSD3 and hepatic CYP1A2 enzymes by a bovine testes extract

Purpose

We investigated the effects of a bovine testes extract (BTE), which was developed as an alternative product for andropausal men, on expression of testicular enzymes responsible for sex hormone synthesis genes and a carcinogen activation related gene.

Methods

Expression of testicular CYP1A2, CYP11A1, CYP17, 3β-HSD, and 17β-HSD3 mRNAs as well as hepatic CYP1A2 mRNA were semi-quantitatively determined by RT-PCR. In addition, expression of hepatic CYP1A2 protein and methoxyresorufin O-demethylase activity were carried out.

Results

Bovine testes extract did not alter the testicular expression of CYP11A1, CYP17, and 3β-HSD mRNAs, while that of CYP11A1 was significantly down-regulated by testosterone. Interestingly, administration of BTE for 3 weeks significantly suppressed testicular 17β-HSD3 and hepatic CYP1A2 mRNA. Correspondingly, methoxyresorufin O-demethylase (MROD) activity and expression of hepatic CYP1A2 protein were significantly decreased.

Conclusions

These findings strongly suggested considering risks versus benefits and raised concerns regarding the use of BTE as an alternative medication or health supplement in andropausal men due to its potential for suppressing expression of both 17β-HSD3 and CYP1A2 mRNAs, testicular enzymes responsible for sex hormone gene synthesis.

Risk of late-onset hypogonadism (andropause) in Brazilian men over 50 years of age with osteoporosis: usefulness of screening questionnaires

OBJECTIVE

To analyze the relative risk of late-onset hypogonadism in men with osteoporosis and the usefulness of screening questionnaires.

METHODS

We correlated the Aging Male's Symptoms (AMS), Androgen Deficiency in Aging Male (ADAM) and International Index of Erectile Function (IIEF-5) questionnaires and the laboratory diagnosis of hypogonadism in 216 men aged 50-84 years (110 with osteoporosis and 106 with normal bone density, paired by age and ethnicity).

RESULTS

Hypogonadism presented in 25% of the osteoporotic and in 12.2 % of normal bone density men (OR 2.08; IC95%: 1.14-3.79) and was associated with ADAM first question (low libido, p=0.013). Levels of TT below 400 ng/dl correlated with an AMS score above 26 (p=0.0278). IIEF-5 showed no correlation with testosterone levels.

CONCLUSION

Hypogonadism was 2.08 times more prevalent in osteoporotic men. The symptom that best correlated with late-onset hypogonadism was low libido (ADAM 1 positive).

The relationship of serum and salivary cortisol levels to male sexual dysfunction as measured by the International Index of Erectile Function

To evaluate the biomarkers of sexual function, we investigated the relationship between questionnaire responses and biological hormones such as testosterone (T) and cortisol (F) in serum and saliva. The study population included 105 men aged 30-72 years (mean: 49+/-4.5, median: 49). Levels of all serum hormones (Total-T, Free-T, Bioavailable-T, Total-F and Bioavailable-F) and salivary hormones (Saliva-T and Saliva-F) were measured directly by liquid chromatography/tandem mass spectrometry. The International Index of Erectile Function (IIEF) was used as a questionnaire to evaluate sexual dysfunction. Free-T and Bioavailable-T showed significant inverse correlations with age (P<0.01). In the group not taking antidepressants, the levels of Bioavailable-F and Saliva-F showed significant inverse correlations with a portion of the IIEF score (P<0.05). However, reductions in Bioavailable-T and Saliva-T showed no association with the IIEF score. In the group taking antidepressants, these hormone levels showed no correlation with IIEF.