Common grounds for erectile dysfunction and coronary artery disease

Can Erectile Dysfunction Severity Predict Major Adverse Cardiovascular Events in Men Undergoing Dialysis? A Prospective Cohort Study

PURPOSE

To evaluate the impact of severe erectile dysfunction (ED) on future major adverse cardiovascular events (MACE) in men on dialysis.

MATERIALS AND METHODS

This prospective cohort study included 71 men on dialysis. ED was assessed using the Sexual Health Inventory for Men (SHIM). Men were divided into the mild/moderate ED (SHIM score ≥8) and severe ED (SHIM score ≤7) groups. The primary endpoint was MACE-free survival. MACE was a composite of myocardial infarction, cardiovascular death, and stroke. The secondary endpoints were cardiac event-free survival and overall survival (OS). Moreover, the predictive abilities of severe ED for 5-year MACE, 5-year cardiac events, and 5-year overall mortality were evaluated.

RESULTS

The median age and follow-up period of the included men were 64 years and 58 months, respectively. The median SHIM score was 4.0; all had a degree of ED, and 64.7% had severe ED. In the background-adjusted multivariable analyses, severe ED was not significantly associated with shorter MACE-free survival (hazard ratio [HR], 1.890; 95% confidence interval [CI], 0.533-6.706; p=0.324), cardiac event-free survival (HR, 2.081; 95% CI, 0.687-6.304; p=0.195), and OS (HR, 0.817; 95% CI, 0.358-1.863; p=0.630). Severe ED did not significantly improve the predictive abilities for 5-year MACE, 5-year cardiac events, and 5-year overall mortality (p=0.110, p=0.101, and p=0.740, respectively).

CONCLUSIONS

ED severity was not associated with shorter MACE-free survival, cardiac event-free survival, or OS, and ED severity could not improve the predictive abilities for these outcomes in men undergoing dialysis.

Identifying potential cross-talk signatures for the occurrence of atherosclerosis in diabetic erectile dysfunction

BACKGROUND

Erectile dysfunction and atherosclerosis are common cardiovascular complications in diseases. Clinical associations between erectile dysfunction and atherosclerosis have been noticed, but the specific mechanisms are not illustrated adequately.

OBJECTIVES

The aim of the study was to further mine associated pathological mechanisms and genetic alterations of atherosclerosis in diabetes mellitus-related erectile dysfunction.

MATERIALS AND METHODS

Significant atherosclerosis-related genes were identified from transcriptome data of diabetes mellitus-related erectile dysfunction and atherosclerosis-related gene sets from DisGeNET and GeneCard databases. Functional enrichment and immune infiltration analyses were performed to clarify the biological roles and pathways as well as immune responses of significant atherosclerosis-related gene sets. A protein-protein interaction network was constructed, and gene clusters were performed. Then, data of diabetic plaques and high-glucose cavernosum endothelial cells were analyzed for validation. And hub atherosclerosis-related gene sets were identified. Finally, expressed pattern of hub atherosclerosis-related gene sets were explored by single-cell profiling and immune analysis.

RESULTS

In total, 202 significant atherosclerosis-related gene sets including 100 upregulated and 102 downregulated genes were identified. These genes were related to endothelial cell migration, inflammatory response, regulation of oxidative stress, and immune response. In immune infiltration, immature dendritic cells and monocytes showed differential expression between the diabetes mellitus-related erectile dysfunction and control groups, A protein-protein interaction network containing 135 nodes was constructed. A hub atherosclerosis-related gene set signature consisting of HBEGF, LOX, NQO1, and VLDLR was obtained by multi-omics validation. In addition, Functional enrichment analysis revealed that hub atherosclerosis-related gene sets were involved in oxidoreductase activity and extracellular matrix organization.

DISCUSSION AND CONCLUSION

We explored atherosclerosis-related genetic changes and signaling pathways in diabetes mellitus-related erectile dysfunction. HBEGF, LOX, NQO1, and VLDLR were identified as hub atherosclerosis-related gene sets. These may serve as potential biomarkers for the clinical management of atherosclerosis and preventing further cardiovascular risks in diabetes mellitus-related erectile dysfunction.

Association between Aortic Calcification Burden and the Severity of Erectile Dysfunction in Men Undergoing Dialysis: A Cross-Sectional Study

PURPOSE

Accelerated atherosclerosis is a major complication in patients with end-stage renal disease and it plays an important role in the pathogenesis of erectile dysfunction (ED). However, the association between aortic calcification burden and the severity of ED remains unclear. The aim of the present study was to investigate this association in men undergoing dialysis.

MATERIALS AND METHODS

This cross-sectional study included 71 men undergoing peritoneal dialysis and/or hemodialysis between July 2016 and May 2018 at Mutsu General Hospital. ED was assessed with the Sexual Health Inventory for Men (SHIM). Patients were divided into the mild/moderate (SHIM score ≥8) and severe ED groups (SHIM score ≤7). Aortic calcification index (ACI) was examined as a clinical indicator of abdominal aortic calcification. Multivariable logistic regression analysis was performed to identify the significant factors associated with severe ED.

RESULTS

The median age of the study participants was 64 years; all had ED, with 64.8% having severe ED. In the multivariable analyses, a slight association was observed between ankle-brachial index and severe ED (odds ratio [OR], 0.058; p=0.072), whereas ACI was significantly associated with severe ED (OR, 1.022; p=0.022).

CONCLUSIONS

Aortic calcification burden was independently associated with severe ED.

Endothelial Dysfunction, Erectile Deficit and Cardiovascular Disease: An Overview of the Pathogenetic Links

Erectile dysfunction (ED) is a condition with multifactorial pathogenesis, quite common among men, especially those above 60 years old. A vascular etiology is the most common cause. The interaction between chronic inflammation, androgens, and cardiovascular risk factors determines macroscopically invisible alterations such as endothelial dysfunction and subsequent atherosclerosis and flow-limiting stenosis that affects both penile and coronary arteries. Thus, ED and cardiovascular disease (CVD) should be considered two different manifestations of the same systemic disorder, with a shared aetiological factor being endothelial dysfunction. Moreover, the penile arteries have a smaller size compared with coronary arteries; thus, for the same level of arteriopathy, a more significant blood flow reduction will occur in erectile tissue compared with coronary circulation. As a result, ED often precedes CVD by 2–5 years, and its diagnosis offers a time window for cardiovascular risk mitigation. Growing evidence suggests, in fact, that patients presenting with ED should be investigated for CVD even if they have no symptoms. Early detection could facilitate prompt intervention and a reduction in long-term complications. In this review, we provide an overview of the pathogenetic mechanisms behind arteriogenic ED and CVD, focusing on the role of endothelial dysfunction as the common denominator of the two disorders. Developed algorithms that may help identify those patients complaining of ED who should undergo detailed cardiologic assessment and receive intensive treatment for risk factors are also analyzed.

Differences in the prevalence of erectile dysfunction between novel subgroups of recent-onset diabetes

AIMS/HYPOTHESIS

In men with diabetes, the prevalence of erectile dysfunction increases with advanced age and longer diabetes duration and is substantially higher in men with type 2 diabetes than those with type 1 diabetes. This study aimed to evaluate the prevalence of erectile dysfunction among the five novel subgroups of recent-onset diabetes and determine the strength of associations between diabetes subgroups and erectile dysfunction.

METHODS

A total of 351 men with recent-onset diabetes (<1 year) from the German Diabetes Study baseline cohort and 124 men without diabetes were included in this cross-sectional study. Erectile dysfunction was assessed with the International Index of Erectile Function (IIEF) questionnaire. Poisson regression models were used to estimate associations between diabetes subgroups (each subgroup tested against the four other subgroups as reference) and erectile dysfunction (dependent binary variable), adjusting for variables used to define diabetes subgroups, high-sensitivity C-reactive protein and depression.

RESULTS

The prevalence of erectile dysfunction was markedly higher in men with diabetes than in men without diabetes (23% vs 11%, p = 0.004). Among men with diabetes, the prevalence of erectile dysfunction was highest in men with severe insulin-resistant diabetes (SIRD) (52%), lowest in men with severe autoimmune diabetes (SAID) (7%), and intermediate in men with severe insulin-deficient diabetes (SIDD), mild obesity-related diabetes (MOD) and mild age-related diabetes (MARD) (31%, 18% and 29%, respectively). Men with SIRD had an adjusted RR of 1.93 (95% CI 1.04, 3.58) for prevalent erectile dysfunction (p = 0.038). Similarly, men with SIDD had an adjusted RR of 3.27 (95% CI 1.18, 9.10) (p = 0.023). In contrast, men with SAID and those with MARD had unadjusted RRs of 0.26 (95% CI 0.11, 0.58) (p = 0.001) and 1.52 (95% CI 1.04, 2.22) (p = 0.027), respectively. However, these associations did not remain statistically significant after adjustment.

CONCLUSIONS/INTERPRETATION

The high RRs for erectile dysfunction in men with recent-onset SIRD and SIDD point to both insulin resistance and insulin deficiency as major contributing factors to this complication, suggesting different mechanisms underlying erectile dysfunction in these subgroups.

Interactions between erectile dysfunction, cardiovascular disease and cardiovascular drugs

Sexual health has a fundamental role in overall health and well-being, and a healthy and dynamic sex life can make an important contribution to a good quality of life. Sexual dysfunction, and especially erectile dysfunction (ED) in men, is highly prevalent in patients with cardiovascular disease (CVD). CVD and ED have shared risk factors and pathophysiological links, such as endothelial dysfunction, inflammation and low plasma testosterone levels. ED has been shown to be an independent and early harbinger of future CVD events, providing an important window to initiate preventive measures. Therefore, screening and diagnosing ED is essential for the primary and secondary prevention of CVD because the assessment of ED offers an easy and low-cost prognostic tool that is an alternative to other investigational cardiovascular biomarkers. Moreover, ED is a major contributing factor to the discontinuation of, or poor adherence to, cardiovascular therapy. Cardiovascular drugs have divergent effects on erectile function, with diuretics and β-blockers having the worst profiles, and renin-angiotensin-aldosterone system inhibitors and nebivolol having the best profiles. Pharmacological treatment of ED has an equivocal effect on the risk of CVD, suggesting a complex interaction between ED and drugs for CVD. In this Review, we discuss how sexual function could be incorporated into the patient history taken by physicians treating individuals with CVD, not merely as part of the diagnostic work-up but as a means to pursue tangible and essential benefits in quality of life and cardiovascular outcomes.

The Prevalence of Erectile Dysfunction and Its Association with Cardiovascular Risk Factors in Patients after Myocardial Infarction

Background and Objectives: This study estimates the prevalence and severity of erectile dysfunction and its association with cardiovascular risk factors in patients after a myocardial infarction. Materials and Methods: This study included men aged 35-80 years, diagnosed with myocardial infarction and examined in the Department of Preventive Cardiology of Vilnius University Hospital Santaros Klinikos between 2016 and 2020. Anthropometric characteristics, blood pressure, lipid profile, blood glucose levels and prevalence of cardiovascular risk factors were evaluated. The International Index of Erectile Function-5 was used to assess patients' erectile function. Results: A total of 171 patients were analysed. The mean age was 57.6 ± 8.8 years. Of the patients, 42.1, 25.1 and 11.7% had three, four and five established cardiovascular risk factors, respectively. Of the patients, 100% were diagnosed with dyslipidaemia, 90.0%-arterial hypertension, 14.6%-diabetes, 23.3%-smoking, 43.7%-positive familial history and 54.5%-insufficient physical activity. The overall prevalence of erectile dysfunction was 62%. It was scored mild in 37.4%, mild-to-moderate-15.2%, moderate-5.3% and severe in 4.1% of the patients. The mean age was significantly different between severity groups (p < 0.001). The study demonstrated a negative correlation between age and total score of the questionnaire (r = -0.308, p < 0.001). Arterial hypertension was more frequent in the patients with erectile dysfunction (p = 0.02). Other cardiovascular risk factors were distributed similarly. Conclusions: Erectile dysfunction is common in patients after a myocardial infarction and its severity is age dependent. The prevalence of cardiovascular risk factors is high, with arterial hypertension significantly more frequent in patients with erectile dysfunction.

Erectile Dysfunction in Men Burdened with the Familial Occurrence of Coronary Artery Disease

Erectile dysfunction (ED) and coronary artery disease (CAD) share common risk factors, some of which have genetic backgrounds, while others may be stimulated by family lifestyle. We investigated the impact of the familial occurrence of CAD on the presence of ED and the presence of classic risk factors for ED in men with CAD. This cross-sectional observational study involved 751 men with CAD who were subjected to cardiac rehabilitation. Overall, 75.63% of the men had ED. CAD was diagnosed in 39.28% of the studied men’s relatives. ED was less frequent in the men with familial CAD than in those without (71.53% vs. 78.29%). Similar relations were observed for the presence of CAD in parents (70.43% vs. 78.34%) and the father (69.95% vs. 77.46%). The International Index of Erectile Function 5 score was significantly higher in patients with familial CAD (median (interquartile range); 17 (12–22) vs. 16 (10–21); p = 0.0118), in parents (18 (12–22) vs. 16 (10–20); p = 0.021), and in the father (18 (12–22) vs. 16 (10–21); p = 0.0499). Age and education minimized the effect of familial CAD. Familial CAD increased the incidence of hypertension, dyslipidemia, and smoking but not sedentary lifestyle. Despite the higher prevalence of selected risk factors for ED in men with familial CAD, a higher incidence of ED was not observed.

The Relationship Between Gensini Score and Erectile Dysfunction in Patients with Chronic Coronary Syndrome

Introduction

In previous studies, the relationship between atherosclerosis and erectile dysfunction (ED) was examined, but the relationship and correlation between Gensini score which evaluates the extent and severity of chronic coronary syndrome (CCS), and ED severity were not investigated.

Aim

To evaluate the relationship between Gensini score and ED in patients with CCS.

Methods

We included 142 consecutive male patients with the diagnosed CCS and underwent an elective coronary angiography between January 2019 and March 2020.

Main Outcome Measure

Correlation analysis demonstrated that Gensini score significantly negatively correlated with the International Index Erectile Function - 5 (IIEF-5) score (r = -0.417, P < .001).

Results

Severe ED was present in 48 (33.8%) patients, moderate ED in 31 (21.8%) patients, and mild ED in 22 (15.5%) patients. 41(28.9%) patients did not have ED. Both the No ED and Mild ED groups were statistically significantly lower than the Severe ED group in terms of the Gensini score (P < .05). When the recommended optimal cut-off point and accuracy measurements were made for the Gensini score, the area under curve (AUC) value in predicting ED was 0.806 (95% CI: 0.732-0.880, P < .001). Multivariate logistic regression analysis demonstrated that independent predictors for ED were Gensini score and age (P < .001, and P = .026, respectively). Every 1 unit increase in Gensini score resulted in a 6% increase in the occurrence of ED (OR = 1.06, CI:1.03-1.10, P < .001).

Conclusion

ED can be caused by endothelial dysfunction. Patients with severe CSS and high Gensini score should be evaluted for ED. ED may be a sign of severe CCS and a high Gensini score. It is also necessary to evaluate cardiological in patients with ED.

Deger M, Ozmen C, Akdogan N, et al. The Relationship Between Gensini Score and Erectile Dysfunction in Patients with Chronic Coronary Syndrome. Sex Med 2021;9:100376.

Erectile dysfunction and coronary artery calcification in incident dialysis patients

PURPOSE

Erectile dysfunction, which has been associated with mortality in the general population, is common in individuals on hemodialysis. Our aim was to determine the relationship between erectile dysfunction, coronary artery calcification and mortality in incident hemodialysis patients.

MATERIALS AND METHODS

A prospective cohort of incident adult dialysis patients with no history of coronary artery disease underwent coronary artery calcification measurement by ECG-triggered multi-slice computed tomography (MSCT) scan at baseline and at least 12 months later. Erectile dysfunction was determined using the 15-item validated International Index of Erectile Function (IIEF-15) questionnaire.

RESULTS

Erectile dysfunction was prevalent in 83% of patients, with 43% classified as severe erectile dysfunction, 22.4% as moderate erectile dysfunction, and 17.2% as mild erectile dysfunction. The median (IQR) coronary artery calcification score was 43.4 (0.25-353.8) for those with erectile dysfunction and 0 (0-0) for those without erectile dysfunction (p = 0.007). More than half (55.6%) of the patients with erectile dysfunction experienced progression of coronary artery calcification compared to 14.3% of patients without erectile dysfunction (p = 0.05). Mortality was 21% during an average follow-up of 5.2 (1.3) years. Twenty-three percent of patients with erectile dysfunction died compared to 10% of people without erectile dysfunction (p = 0.4). Erectile dysfunction was not significantly associated with mortality [HR 1.2 (1.3), p = 0.87].

CONCLUSIONS

Erectile dysfunction is common in individuals who start dialysis. It is significantly associated with an increased coronary artery calcification score, however, it is not associated with increased mortality in incident dialysis patients with no history of coronary artery disease.

Erectile Dysfunction in Men With Psoriatic Arthritis: A Population-based Cohort Study

OBJECTIVE

To define the incidence of erectile dysfunction (ED) in a population-based cohort of men with psoriatic arthritis (PsA).

METHODS

Data pertaining to demographics, ED, and potential confounding diagnosis were extracted from a comprehensive medical record system for a population-based cohort of men with PsA and an age-matched male comparator cohort. Cumulative incidence of ED adjusted for competing risk of death was compared between the 2 cohorts.

RESULTS

There were 128 age-matched pairs of men with PsA and without PsA in the described cohorts. At baseline, there was a 7% prevalence of ED in men with PsA prior to diagnosis compared to a 3% prevalence of ED in the comparator cohort (P = 0.16). After PsA diagnosis/index date, diagnosis with PsA was associated with an increased risk of ED (age-adjusted HR 1.45, 95% CI 0.79-2.68), but this association did not reach statistical significance. This was based on 24 cases of ED in the men with PsA and 18 cases within the comparator cohort. No confounding factors or ED treatment strategies differed significantly between men with PsA and ED and comparators with ED.

CONCLUSION

Men with PsA may have an increased risk of ED, which was detected but likely underpowered in this study. Whether this difference is secondary to higher prevalence of traditional risk factors of ED in men with PsA compared to the general population will require further study.

The erectile dysfunction as a marker of cardiovascular disease: a review

Cardiovascular disease (CVD) and erectile dysfunction (ED) are two conditions that often coexist. Both diseases are consequences of the systemic vascular disease, sharing common risk factors, like diabetes mellitus, arterial hypertension, smoking, obesity, dyslipidaemia. Furthermore, they share the same pathological basis, endothelial dysfunction. Symptoms of ED precede with three to five years the clinical manifestations of CVD. This period may be a window of opportunity for the early initiation of a prompt therapeutic action for cardiovascular risk factors. This article reviews the incidence and prevalence of CVD and ED, the common risk factors, the pathophysiological link between the two diseases, and the current diagnosis and management strategies of patients with CVD and ED, in order to prevent myocardial infarction, stroke or heart failure.

Association of erectile dysfunction and type II diabetes mellitus at a tertiary care centre of south India

BACKGROUND AND AIMS

Erectile Dysfunction (ED) is more common in diabetic men and, unfortunately, occurs at an earlier age in diabetic patients when compared with the general population. The study aims to evaluate the independent predictors of ED in adult men with type 2 diabetes mellitus (DM) at a tertiary care center of South India.

METHODS

A total of 720 men aged 30-70 years who had been diagnosed with type 2 DM were enrolled for the study from January 2017 to January 2020 from the outpatient diabetes clinic of the Hospital. All patients completed the abridged version of the International Index of Erectile Function (IIEF-5) questionnaire.

RESULTS

The mean age of the patients was (58.4 ± 7.8 years). 68.6% of subjects had varying degrees of erectile dysfunction, of which 54.6% had moderate to severe ED. 55.8% had poor glycemic control (HbA1c ≥ 7%). Subjects with ED had a longer duration of DM than those without ED (mean DM duration was 8.1 ± 4.9 years versus 4.4 ± 3.5 years; p < 0.001). Longer duration of DM, poor glycemic control, hypertension, peripheral arterial disease, testosterone deficiency were all independent predictors ED (p < 0.05).

CONCLUSIONS

A high incidence of erectile dysfunction was observed in type 2 DM patients attending the diabetic clinic, and over half of the people affected were of moderate-to-severe in intensity. Poor glycemic control, testosterone deficiency, peripheral arterial disease were the modifiable risk factors for ED in diabetic subjects. At the same time, a longer duration of type 2 DM was noticed as a glaring non-modifiable risk factor, according to our study.

Vitamin D and Male Erectile Function: An Updated Review

Literature support that vitamin-D is important for different systems of the human body including, but not limited to endocrine and immune systems, vasculature and endothelial function of the body. Male erectile function depends on many factors and can be perceived as a health indicator of the body. Epidemiological data have shown that vitamin-D deficiency is also associated with erectile dysfunction. In this review, our aim is to interpret the mechanisms by which vitamin-D might regulate anatomy and physiology of penis. Evidence showed that vitamin-D is needed for an adequate erectile function. Briefly, vitamin-D is crucial for a better healthy body and sexual activity.

Effect of Ticagrelor, a Cytochrome P450 3A4 Inhibitor, on the Pharmacokinetics of Tadalafil in Rats

Tadalafil is a cytochrome P450 (CYP) 3A4 substrate. Because there are few data on drug-drug interactions, it is advisable to take sufficient consideration when co-administering tadalafil with CYP3A4 inducers or inhibitors. This study was conducted to assess the effect of ticagrelor, a CYP3A4 inhibitor, on the pharmacokinetic properties of tadalafil after oral administration to rats. A total of 20 Sprague–Dawley male rats were randomly divided into the non-pretreated group and ticagrelor-pretreated group, and tadalafil was orally administered to each group after pretreatment with or without ticagrelor. Blood samples were collected at predetermined time points after oral administration of tadalafil. As a result, systemic exposure of tadalafil in the ticagrelor-pretreated group was significantly increased compared to the non-pretreated group (1.61-fold), and the clearance of tadalafil in the ticagrelor-pretreated group was significantly reduced than the non-pretreated group (37%). The prediction of the drug profile through the one-compartment model could explain the differences of pharmacokinetic properties of tadalafil in the non-pretreated and ticagrelor-pretreated groups. This study suggests that ticagrelor reduces a CYP3A-mediated tadalafil metabolism and that tadalafil and a combination regimen with tadalafil and ticagrelor requires dose control and specific pharmacotherapy.

Choroidal Thickness Analysis in Patients with Erectile Dysfunction

Purpose

To investigate the morphological features of choroidal vasculature in patients with erectile dysfunction (ED) by analyzing choroidal thickness using optical coherence tomography.

Materials and Methods

We enrolled 39 patients with ED and 19 controls. ED was defined as an erectile function domain score <26 on the International Index of Erectile Function (IIEF) questionnaire. Small-choroidal-vessel-layer (SCVL) thickness was calculated by subtracting large-choroidal-vessel-layer (which corresponded to Haller's layer) thickness from total choroidal thickness. Choroidal thickness was compared between the ED and control groups.

Results

SCVL thickness was lesser in the ED group than in the control group (control, 69.8±24.3 µm vs. ED, 55.1±19.9 µm; p=0.017). Among patients without diabetes, the ED group showed significantly lesser SCVL thickness than did the control group (control, 77.1±22.7 µm vs. ED, 56.5±20.9 µm; p=0.021). However, among patients with diabetes, choroidal thickness showed no significant intergroup difference. Multiple linear regression analysis revealed that spherical equivalent (standardized coefficient β=0.294; p=0.019) and the IIEF erectile function score (standardized coefficient β=0.315; p=0.012) were significantly associated with SCVL thickness.

Conclusions

SCVL thickness, including the choriocapillaris layer and medium-sized choroidal vascular layer, decreased in proportion to ED severity, suggesting that microvascular changes in choroidal vessels may occur before specific ocular diseases in patients with ED.

Erectile Dysfunction and Ischaemic Heart Disease

Erectile dysfunction (ED) is a common disorder that affects the quality of life of many patients. It is prevalent in more than half of males aged over 60 years. Increasing evidence suggests that ED is predominantly a vascular disorder. Endothelial dysfunction seems to be the common pathological process causing ED. Many common risk factors for atherosclerosis such as diabetes, hypertension, smoking, obesity and hyperlipidaemia are prevalent in patients with ED and so management of these common cardiovascular risk factors can potentially prevent ED. Phosphodiesterase type 5 inhibitors provide short-term change of haemodynamic factors to help initiate and maintain penile erection. They have been shown to be an effective and safe treatment strategy for ED in patients with heart disease, including those with ischaemic heart disease and hypertension.

Association between coronary heart disease and erectile dysfunction in Chinese Han population

To investigate the association between coronary heart disease (CHD) and erectile dysfunction (ED) in Chinese Han population. Patients who went to the andrological out-patient clinic of our hospital between August 1, 2015 and May 1, 2016 and met all eligible criteria were enrolled in this study. The patients diagnosed as ED using self-administered International Index of Erectile Function-5 (IIEF-5) questionnaire were considered as case group and others were considered as control. The cases were categorized as mild, moderate, and severe ED. Subjects were interviewed for the history of CHD. Uni- and multivariate logistic regression models were used to calculate odds ratios (ORs) and corresponding 95% confidence intervals (CIs) using the SPSS 18.0 software. A total of 240 participants (56 ED patients and 184 controls) were enrolled. CHD prevalence was higher in cases without statistical significance (OR = 1.20, 95%CI = 0.63-2.29; p = 0.58). Results of adjusted analysis also showed a non-significantly increased risk (OR = 1.25, 95%CI = 0.55-2.85; p = 0.59). Stratified analysis by severity of ED revealed similar results. This study suggests no significant association exists between CHD and ED in Chinese Han population.

Sexual Function and Mortality in Older Men: The Concord Health and Ageing in Men Project

Background

The longitudinal association between progressive temporal change in sexual (dys)function and mortality in older men.

Methods

Community-dwelling men aged 70 years and older from the Concord Health and Ageing in Men Project were assessed at baseline (2005-2007, n = 1,705), 2-years follow-up (n = 1,367), and 5-years follow-up (n = 958). Self-reported sexual function (erectile function and sexual activity) using standardized questions were analyzed by generalized estimating equations to examine the longitudinal prediction of mortality according to change in sexual function across three time-points.

Results

Men reported to have erectile dysfunction increased from 64% to 80%, and to be sexually inactive increased from 56% to 59% over the course follow-up. In univariate analyses, erectile dysfunction (hazard ratio: 2.02, 95% confidence interval [CI]: 1.45-2.81) or having no sexual activity (hazard ratio: 2.31, 95% CI: 1.82-2.93) at baseline predicted increased mortality over the subsequent 7 years. Models adjusted for multivariate and major reproductive hormones had negligible impact on mortality prediction, but neither statistically significantly predicted mortality after adjusting for depression. Similarly, change in erectile dysfunction over time was associated with mortality over 7 years in univariate (odds ratio: 1.69, 95% CI: 1.34-2.14) and multivariate analysis, including hormones, but not after adjusting for depression (odds ratio: 1.24, 95% CI: 0.95-1.62). Change in sexual activity was associated with mortality over 7 years in univariate analysis (odds ratio: 2.37, 95% CI: 1.33-4.20) but not after adjusting for age (odds ratio: 1.45, 95% CI: 0.79-2.64).

Conclusions

Our analyses suggest sexual dysfunction was not an independent risk factor of, but rather may be a biomarker for, all-cause mortality in older men.

Lower urinary tract symptoms/benign prostatic hypertrophy and vascular function: Role of the nitric oxide-phosphodiesterase type 5-cyclic guanosine 3',5'-monophosphate pathway

It is well known that there is an association of lower urinary tract symptoms/benign prostatic hypertrophy with cardiovascular disease, suggesting that lower urinary tract symptoms/benign prostatic hypertrophy is a risk factor for cardiovascular events. Vascular function, including endothelial function and vascular smooth muscle function, is involved in the pathogenesis, maintenance and development of atherosclerosis, leading to cardiovascular events. Vascular dysfunction per se should also contribute to lower urinary tract symptoms/benign prostatic hypertrophy. Both lower urinary tract symptoms/benign prostatic hypertrophy and vascular dysfunction have cardiovascular risk factors, such as hypertension, dyslipidemia, diabetes mellitus, aging, obesity and smoking. Inactivation of the phosphodiesterase type 5-cyclic guanosine 3',5'-monophosphate-nitric oxide pathway causes lower urinary tract symptoms/benign prostatic hypertrophy through an enhancement of sympathetic nervous activity, endothelial dysfunction, increase in Rho-associated kinase activity and vasoconstriction, and decrease in blood flow of pelvic viscera. Both endogenous nitric oxide and exogenous nitric oxide act as vasodilators on vascular smooth muscle cells through an increase in the content of cyclic guanosine 3',5'-monophosphate, which is inactivated by phosphodiesterase type 5. In a clinical setting, phosphodiesterase type 5 inhibitors are widely used in patients with lower urinary tract symptoms/benign prostatic hypertrophy. Phosphodiesterase type 5 inhibitors might have beneficial effects on vascular function through not only inhibition of cyclic guanosine 3',5'-monophosphate degradation, but also increases in testosterone levels and nitric oxide bioavailability, increase in the number and improvement of the function of endothelial progenitor cells, and decrease in insulin resistance. In the present review, the relationships between lower urinary tract symptoms/benign prostatic hypertrophy, the phosphodiesterase type 5-nitric oxide-cyclic guanosine 3',5'-monophosphate pathway, vascular function and cardiovascular outcomes are examined.

Erectile dysfunction, metabolic syndrome, and cardiovascular risks: facts and controversies

Erectile dysfunction (ED) is the most common male sexual dysfunction, and shares many risk factors with systemic conditions including cardiovascular disease (CVD) and the metabolic syndrome (MetS). ED is considered to be an independent risk factor for CVD and can be a harbinger of future cardiovascular events. Given this relationship, each encounter for ED should be viewed by healthcare providers as an opportunity to screen for CVD and other comorbid conditions, including the MetS, that can significantly affect a man's overall health. While universally accepted screening guidelines are lacking, expert panels do recommend an approach to risk stratification in men with ED. In this review, we discuss the current state of understanding of the relationship between ED, the MetS, and CV risk, and how this impacts the approach to the patient presenting with ED.

Prevalence of Erectile Dysfunction and Associated Factors in Korean Older Adults With Coronary Artery Disease

The current study aimed to identify the prevalence and associated factors of erectile dysfunction (ED) among 161 Korean adults 60 and older with coronary artery disease (CAD). ED was diagnosed in 72.2% of patients-the prevalence of which was significantly associated with age, education, employment, monthly income, frequency of sexual intercourse, body mass index, and low-density lipoprotein. Health-related quality of life (HRQoL) was lower in patients with ED than in those without ED (p < 0.001). Hierarchical multiple regression analysis revealed that ED significantly influenced HRQoL in patients with CAD after adjusting for sociodemographic and disease-related characteristic variables (p < 0.001). Interventions and training courses for health care providers should focus on improving caregivers' knowledge and communication skills with patients and spouses regarding sexual health. Furthermore, guidelines to improve HRQoL in patients with CAD should consider incorporating sexual counseling. [Journal of Gerontological Nursing, 42(10), 32-41.].

The impact of sexual therapy on patients after cardiac events participating in a cardiac rehabilitation program

Aims

To assess the impact of a sexual therapy module on male patients participating in phase 2 cardiac rehabilitation after a cardiac event.

Methods and results

We randomly assigned 92 consecutive male patients (age ≤ 70 years, mean age 58 years), on their admission to phase 2 cardiac rehabilitation after myocardial infarction/acute coronary syndromes and/or coronary artery bypass graft, into a ‘sexual therapy group’ ( n = 47) and a ‘control group’ ( n = 45). Two cotherapists met with the patient and spouse for 5 h in three sessions, in addition to cardiac rehabilitation. Sexual therapy included patient education, cognitive restructuring, emotional support, guided imagery, and medication (Viagra). Controls participated in cardiac rehabilitation without sexual therapy. Self-report questionnaires were used three times: before, 1, and 4 months after sexual therapy. Baseline characteristics of both groups were similar. More sexual therapy patients resumed sexual activity within 1 month (87% vs. 50% in control). Sexual therapy patients improved more than controls in quality of sexual function in terms of libido, confidence to attain erection, satisfaction with sexual relationship, frequency of erection, and enjoyment of sex. Sexual therapy patients were highly satisfied with cardiac rehabilitation and sexual therapy.

Conclusion

Sexual therapy is significantly effective in improving the frequency and quality of sexual activity in a patient's postcardiac event beyond the usual cardiac rehabilitation. Sexual therapy should be an integral part of cardiac rehabilitation. Eur J Cardiovasc Prev Rehabil14:672-678 © 2007 The European Society of Cardiology

Pharmacogenetics of erectile dysfunction: navigating into uncharted waters

Sildenafil and other PDE-5 inhibitors have revolutionized erectile dysfunction (ED) treatment. However, a significant number of patients do not respond or present adverse reactions to these drugs. While genetic polymorphisms may underlie this phenomenon, very little research has been undertaken in this research field. Most of the current knowledge is based on sildenafil, thus almost completely ignoring other important pharmacological therapies. Currently, the most promising genes with pharmacogenetic implications in ED are related to the nitric oxide and cGMP pathway, although other genes are likely to affect the responsiveness to treatment of ED. Nevertheless, the small number of studies available opens the possibility of further exploring other genes and phenotypes related to ED. This article provides a comprehensive overview of the genes being tested for their pharmacogenetic relevance in the therapy of ED.

A comprehensive review of metabolic syndrome affecting erectile dysfunction

INTRODUCTION

Metabolic syndrome (MetS) is the most important public health issue threatening the health of men and women all over the world. Its current prevalence (i.e., approximately 30%) is continuously increasing. MetS by itself is considered a risk factor for erectile dysfunction (ED).

AIM

To focus on the definition epidemiology, pathogenesis, and possible mechanistic links between MetS and ED in order to provide guidelines for treating such individuals.

METHODS

The search strategies yielded total records screened from PubMed.

MAIN OUTCOME MEASURES

Regardless of the definition, MetS consists of insulin resistance, hypertension, dyslipidemia, and obesity. MetS is not an end disease but is a disorder of energy utilization and storage.

RESULTS

The prevalence of ED in patients with MetS is almost twice than in those without MetS, and about 40% of patients with ED have MetS. An important mechanism linking MetS and ED is hypogonadism.

CONCLUSIONS

Recognizing through ED, underlying conditions such as hypogonadism, diabetes and MetS might be a useful motivation for men to improve their health-related choices. The clinical management of MetS can be done by therapeutic interventions that include lifestyle modifications, hormone replacement alone or in combination with phosphodiesterase 5 inhibitors, and other pharmacological treatments.

Association between erectile dysfunction and echocardiographic variables of ventricular hypertrophy and diastolic function in hypertensive patients with type 2 diabetes mellitus: a cross-sectional study

BACKGROUND

This study was conducted among individuals with diabetes and hypertension in order to assess the prevalence of erectile dysfunction (ED) and the association between ED and cardiovascular risk variables such as echocardiographic changes.

METHODS

We evaluated 114 men with type 2 diabetes mellitus and hypertension. ED was assessed by International Index of Erectile Function (IIEF-5) score. Clinical and laboratory variables were evaluated, including C-reactive protein (CRP), ambulatory blood pressure monitoring (ABPM), ankle brachial index (ABI) and transthoracic echocardiography. Comparisons between patients with ED (IIEF-5 < 22) and without ED (IIEF-5 ≥ 22) were performed.

RESULTS

Patients were 56.8 ± 5.7 years-old, systolic and diastolic blood pressure were 150.7 ± 19.5 mmHg and 85.4 ± 11.4 mmHg, respectively, and HbA1c was 8.0 ± 1.7%. The majority (74.6%) of patients had ED. Levels of CRP, ABPM values and ABI were similar between men with and without ED. Echocardiography variables related to cardiac chamber diameters, left ventricular hypertrophy and diastolic function were similar between groups, except there was a slight lower left ventricular ejection fraction in men with ED (64.9 ± 7.3 vs 68.1 ± 3.9%, P = 0.004).

CONCLUSIONS

In high cardiovascular risk hypertensive individuals with type 2 diabetes, ED is highly prevalent as expected, but its presence is associated with neither echocardiographic variables, nor other cardiovascular risk factors.

Metabolic syndrome and risk for ED: a meta-analysis

There are many recent observational studies on metabolic syndrome (MS) and the risk for ED, and it is still inconclusive whether MS increases the risk for ED. This meta-analysis aims to detect a relationship between MS and ED. We identified eligible studies by searching PubMed, Embase and the Cochrane Library for articles published before August 2013. Adjusted relative risks (RR) with 95% confidence interval (CI) were calculated using random-effects or fixed-effects models. A total of 10 studies involving 4092 participants were included in the meta-analysis. MS was associated with an increased incidence of ED (RR=1.60, 95% CI=1.27-2.02, P<0.001), with significant evidence of heterogeneity among these studies (P for heterogeneity <0.001, I(2)=92.9%). The subgroup and sensitivity analyses confirmed the stability of the results and no publication bias was detected. The present meta-analysis suggests that MS is significantly associated with the risk for ED. Large-scale and well-designed prospective studies are required to further investigate the association between MS and risk for ED.

A systematic review of the association between erectile dysfunction and cardiovascular disease

CONTEXT

Erectile dysfunction (ED) is considered a vascular impairment that shares many risk factors with cardiovascular disease (CVD). A correlation between ED and CVD has been hypothesized, and ED has been proposed as an early marker of symptomatic CVD.

OBJECTIVE

To analyze the relationship between ED and CVD, evaluating the pathophysiologic links between these conditions, and to identify which patients would benefit from cardiologic assessment when presenting with ED.

EVIDENCE ACQUISITION

A systematic literature review searching Medline, Embase, and Web of Science databases was performed. The search strategy included the terms erectile dysfunction, cardiovascular disease, coronary artery disease, risk factors, pathophysiology, atherosclerosis, low androgen levels, inflammation, screening, and phosphodiesterase type 5 inhibitors alone or in combination. We limited our search to studies published between January 2005 and May 2013.

EVIDENCE SYNTHESIS

Several studies reported an association between ED and CVD. The link between these conditions might reside in the interaction between androgens, chronic inflammation, and cardiovascular risk factors that determines endothelial dysfunction and atherosclerosis, resulting in disorders of penile and coronary circulation. Because penile artery size is smaller compared with coronary arteries, the same level of endothelial dysfunction causes a more significant reduction of blood flow in erectile tissues compared with that in coronary circulation. Thus ED could be an indicator of systemic endothelial dysfunction. From a clinical standpoint, because ED may precede CVD, it can be used as an early marker to identify men at higher risk of CVD events. ED patients at high risk of CVD should undergo detailed cardiologic assessment and receive intensive treatment of risk factors.

CONCLUSIONS

ED and CVD should be regarded as two different manifestations of the same systemic disorder. ED usually precedes CVD onset, and it might be considered an early marker of symptomatic CVD.

Erectile dysfunction precedes and is associated with severity of coronary artery disease among Asian Indians

INTRODUCTION

Erectile dysfunction (ED) and coronary artery disease (CAD) often share common risk factors, and there is growing evidence that ED might serve as a clinical marker for cardiovascular disease. Despite rising trends of CAD in Asian Indians, limited data are available on the prevalence of ED and its correlation with CAD severity in such patients.

AIM

To study the prevalence of ED in Asian Indian patients undergoing coronary angiography and to assess if the severity of ED correlates with angiographic severity of CAD.

METHODS

In all patients undergoing coronary angiography, ED was assessed using the International Index of Erectile Function-5 questionnaire.

MAIN OUTCOME MEASURES AND RESULTS

Among 175 male patients, ED was present in 70%; patients with ED had a higher incidence of multivessel CAD (80% vs. 36%, P 0.001), diffuse CAD (81% vs. 34%, P 0.001), and higher number of mean coronary vessels involved compared with those without ED. Those with severe ED had higher prevalence of multivessel CAD and higher number of mean coronary vessels involved compared with those with milder grades of ED. Onset of symptoms of ED preceded symptoms of CAD by a mean of 24.6 months in 84% of patients. The presence of severe ED was associated with a 21-fold higher risk of having triple-vessel disease (odds ratio [OR] 21.94, 95% confidence interval [CI] 3.41-141.09, P = 0.001) and an 18-fold higher risk of having diffuse angiographic CAD (OR 17.91, 95% CI 3.11-111.09, P = 0.001).

CONCLUSION

Asian Indians with angiographic CAD frequently have ED; symptoms of ED precede that of CAD in most patients. Incidence of multivessel and diffuse CAD is significantly more common in patients with ED. It is important for physicians to be aware of the close relationship between the two conditions so that patients with ED can have optimal risk stratification for concomitant CAD whenever required.

Tratamento endovascular da disfunção erétil por fístula arterioesponjosa traumática: relato de caso

A disfunção erétil (DE) representa um distúrbio comum de caráter multifatorial. Os autores relatam um caso de paciente vítima de trauma perineal evoluindo com DE por fístula da artéria bulbar para o corpo esponjoso peniano, promovendo um shunt arteriovenoso culminando com déficit de ereção, congestão peniana e dor. O mesmo foi submetido ao tratamento endovascular por embolização com sucesso e encontra-se no sexto mês de acompanhamento ambulatorial, com retorno às suas atividades sexuais e sem queixas de rigidez peniana e dor.

Evaluation of a multi-herb supplement for erectile dysfunction: a randomized double-blind, placebo-controlled study

Background

Evidence is lacking for multi-ingredient herbal supplements claiming therapeutic effect in sexual dysfunction in men. We examined the safety and efficacy of VigRX Plus (VXP) – a proprietary polyherbal preparation for improving male sexual function, in a double blind, randomized placebo-controlled, parallel groups, multi-centre study.

Methods

78 men aged 25–50 years of age; suffering from mild to moderate erectile dysfunction (ED), participated in this study. Subjects were randomized to receive VXP or placebo at a dose of two capsules twice daily for 12 weeks. The international index of erectile function (IIEF) was the primary outcome measure of efficacy. Other efficacy measures were: Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS), Serum testosterone, Semen analysis, Investigator’s Global assessment and Subjects’ opinion.

Results

In subjects receiving VXP, the IIEF-Erectile Function (EF) scores improved significantly as compared to placebo. After 12 weeks of treatment, the mean (sd) IIEF-EF score at baseline increased from 16.08 (2.87) to 25.08 (4.56) in the VXP group versus 15.86 (3.24) to 16.47 (4.25) in the placebo group (P < 0.0001). Similar results were observed in each of the remaining four domains of the IIEF (orgasmic function, sexual desire, intercourse satisfaction, and overall satisfaction).There was a significant difference for VXP versus placebo comparison of mean (sd) EDITS scores of patients: 82.31(20.23) vs 36.78(22.53) and partners :(82.75(9.8) vs 18.50(9.44);P < 0.001. Thirty-five out of 39 (90%) subjects from the VXP group and one (3%) from the placebo group wished to continue with the treatment they received. Investigator’s global assessment rated VXP therapy as very good to excellent in more than 50% patients and placebo therapy as fair to good in about 25% of patients. Incidence of side effects and subject’s rating for tolerability of treatment was similar in both groups.

Conclusions

VigRX Plus was well tolerated and more effective than placebo in improving sexual function in men.

Trial Registration

Clinical Trial Registry India, CTRI/2009/091/000099, 31-03-2009

Breaking the silence: helping men with erectile dysfunction

Erectile dysfunction is a condition that is often under-reported. This article provides the community nurse with a brief overview of erectile dysfunction in the context of sexual health and its importance to wellbeing. The article outlines issues concerning epidemiology, the possible causes of erectile dysfunction and the impact the condition can have on the man's quality of life. Often men with erectile dysfunction report being stigmatised, feeling shame and experiencing guilt. The role of the community nurse in assessing, making a diagnosis and helping the man with the condition is described. The article emphasises the fact that in order to offer care effectively and competently the community nurse must be up to date and knowledgeable concerning the condition.

Men's health: sexual dysfunction, physical, and psychological health--is there a link?

INTRODUCTION

Sexual dysfunction in men, such as erectile dysfunction, hypogonadism, and premature ejaculation, generates considerable attention. Its association with physical and psychological health is an issue which should be addressed seriously.

AIM

A review of the literature pertaining to the correlation between sexual dysfunction and physical and psychological health.

METHODS

PubMed search for relevant publications on the association between sexual dysfunction in men and physical and psychological health.

MAIN OUTCOME MEASURE

Clinical and epidemiological evidence that demonstrates the association between sexual dysfunction in men and physical and psychological health.

RESULTS

Sexual dysfunction, i.e., erectile dysfunction, hypogonadism, and premature ejaculation, has been shown to be associated with physical and psychological health. There is a strong correlation between sexual dysfunction and cardiovascular disease, metabolic syndrome, quality of life, and depression.

CONCLUSION

The association between men's sexual dysfunction and physical and psychological health is real and proven. Therefore, it should not be taken lightly but instead treated as a life-threatening medical problem.

Should patients with erectile dysfunction be evaluated for cardiovascular disease?

The landmark Massachusetts Male Ageing Study shed new light on the prevalence of erectile dysfunction (ED) and drew attention to ED as a disease of ageing. Over the years, ED has been linked to the development of cardiovascular disease (CVD) in some patients. There is clear evidence that ED and CVD share and have a similar risk factor profile. CVD is one of the most recognizable causes of mortality and early detection coupled with prevention of mortality from CVD has been the prime interest of many researchers. Consequently, there has been a multidisciplinary curiosity regarding the proposal to use ED as a marker for future CVD. In fact, there have been several proposals to use ED as a screening tool for future CVD. We performed a comprehensive search of two main databases-PubMed and Cochrane Library using a combination of keywords such as acute myocardial infarction, coronary artery disease (CAD) and ED. Journal articles from January 2000 to June 2011 were reviewed. We included all articles discussing the relationship between ED and CVD in the English language. All the relevant randomized controlled trials, cohort and retrospective studies, and review articles were included in our overall analysis in an attempt to answer the question whether all patients with ED should be clinically evaluated for CVD. The results showed a link between ED and the development of future CVD in some patients, but ED was not shown to be an independent risk predictor that is any better than the traditional Framingham risk factors. Screening for CVD may, however, be rewarding in younger patients with severe ED and in patients with concurrent CVD risk factors.

Erectile dysfunction and risk of cardiovascular disease: meta-analysis of prospective cohort studies

OBJECTIVES

Our goal was to evaluate the association between erectile dysfunction (ED) and risk of cardiovascular disease (CVD) and all-cause mortality by conducting a meta-analysis of prospective cohort studies.

BACKGROUND

Observational studies suggest an association between ED and the incidence of CVD. However, whether ED is an independent risk factor of CVD remains controversial.

METHODS

The PubMed database was searched through January 2011 to identify studies that met pre-stated inclusion criteria. Reference lists of retrieved articles were also reviewed. Two authors independently extracted information on the designs of the studies, the characteristics of the study participants, exposure and outcome assessments, and control for potential confounding factors. Either a fixed- or a random-effects model was used to calculate the overall combined risk estimates.

RESULTS

Twelve prospective cohort studies involving 36,744 participants were included in the meta-analysis. The overall combined relative risks for men with ED compared with the reference group were 1.48 (95% confidence interval [CI]: 1.25 to 1.74) for CVD, 1.46 (95% CI: 1.31 to 1.63) for coronary heart disease, 1.35 (95% CI: 1.19 to 1.54) for stroke, and 1.19 (95% CI: 1.05 to 1.34) for all-cause mortality. Sensitivity analysis restricted to studies with control for conventional cardiovascular risk factors yielded similar results. No evidence of publication bias was observed.

CONCLUSIONS

This meta-analysis of prospective cohort studies suggests that ED significantly increases the risk of CVD, coronary heart disease, stroke, and all-cause mortality, and the increase is probably independent of conventional cardiovascular risk factors.

Does erectile dysfunction contribute to cardiovascular disease risk prediction beyond the Framingham risk score?

OBJECTIVES

This study was designed to determine whether erectile dysfunction (ED) predicts cardiovascular disease (CVD) beyond traditional risk factors.

BACKGROUND

Both ED and CVD share pathophysiological mechanisms and often co-occur. It is unknown whether ED improves the prediction of CVD beyond traditional risk factors.

METHODS

This was a prospective, population-based study of 1,709 men (of 3,258 eligible) age 40 to 70 years. The ED data were measured by self-report. Subjects were followed for CVD for an average follow-up of 11.7 years. The association between ED and CVD was examined using the Cox proportional hazards regression model. The discriminatory capability of ED was examined using C statistics. The reclassification of CVD risk associated with ED was assessed using a method that quantifies net reclassification improvement.

RESULTS

Of the prospective population, 1,057 men with complete risk factor data who were free of CVD and diabetes at baseline were included. During follow-up, 261 new cases of CVD occurred. We found ED was associated with CVD incidence controlling for age (hazard ratio [HR]: 1.42, 95% confidence interval [CI]: 1.05 to 1.90), age and traditional CVD risk factors (HR: 1.41, 95% CI: 1.05 to 1.90), as well as age and Framingham risk score (HR: 1.40, 95% CI: 1.04 to 1.88). Despite these significant findings, ED did not significantly improve the prediction of CVD incidence beyond traditional risk factors.

CONCLUSIONS

Independent of established CVD risk factors, ED is significantly associated with increased CVD incidence. Nonetheless, ED does not improve the prediction of who will and will not develop CVD beyond that offered by traditional risk factors.

Molecular targets for diabetes mellitus-associated erectile dysfunction

Protein expression profiles in rat corporal smooth muscle tissue were compared between animal models of streptozotocin-induced diabetes mellitus (STZ-DM) and age-matched controls (AMCs) at 1 week and 2 months after induction of hyperglycemia with STZ treatment. At each time point, protein samples from four STZ-DM and four AMC rat corpora tissues were prepared independently and analyzed together across multiple quantitative two-dimensional gels using a pooled internal standard sample to quantify expression changes with statistical confidence. A total of 170 spots were differential expressed among the four experimental groups. A subsequent mass spectrometry analysis of the 170 spots identified a total of 57 unique proteins. Network analysis of these proteins using MetaCore suggested altered activity of transcriptional factors that are of too low abundance to be detected by the two-dimensional gel method. The proteins that were down-regulated with diabetes include isoforms of collagen that are precursors to fibril-forming collagen type 1; Hsp47, which assists and mediates the proper folding of procollagen; and several proteins whose abundance is controlled by sex hormones (e.g. CRP1 and A2U). On the other hand, proteins seen or predicted to be up-regulated include proteins involved in cell apoptosis (e.g. p53, 14-3-3-gamma, Serpinf1, Cct4, Cct5, and Sepina3n), proteins that neutralize the biological activity of nerve growth factor (e.g. anti-NGF 30), and proteins involved in lipid metabolism (e.g. apoA-I and apoA-IV). Subsequent Western blot validation analysis of p53, 14-3-3-gamma, and Hsp47 confirmed increased p53 and 14-3-3-gamma and decreased Hsp47 levels in separate samples. According to the results from the Western blot analysis, Hsp47 protein showed a approximately 3-fold decrease at 1 week and was virtually undetectable at 2 months in diabetic versus control. Taken together, our results identify novel candidate proteins playing a role in erectile dysfunction in diabetes resulting from STZ treatment.

NS11021, a novel opener of large-conductance Ca(2+)-activated K(+) channels, enhances erectile responses in rats

BACKGROUND AND PURPOSE

Large-conductance Ca(2+)-activated K(+) channels (BK(Ca)), located on the arterial and corporal smooth muscle, are potential targets for treatment of erectile dysfunction (ED). This study investigated whether NS11021 (1-(3,5-Bis-trifluoromethyl-phenyl)-3-[4-bromo-2-(1H-tetrazol-5-yl)-phenyl]-thiourea), a novel opener of BK(Ca) channels, relaxes erectile tissue in vitro and enhances erectile responses in intact rats. The effects were compared with sildenafil, an inhibitor of phosphodiesterase type 5.

EXPERIMENTAL APPROACH

Patch clamp was used to record whole cell current in rat isolated corpus cavernosum smooth muscle cells (SMCs) and human umbilical vein endothelial cells (HUVECs). Isometric tension was measured in intracavernous arterial rings and corpus cavernosum strips isolated from rats and men, and simultaneous measurements of intracellular Ca(2+) concentration ([Ca(2+)](i)) and tension were performed in intracavernous arteries. Erectile response was measured in anaesthetized rats.

KEY RESULTS

In patch clamp recordings, NS11021 increased currents sensitive to the selective BK(Ca) channel blocker, iberiotoxin (IbTX) in SMCs, but did not modulate K(+) current in HUVECs. NS11021 reduced [Ca(2+)](i) and tension in penile arteries. IbTX inhibited the vasorelaxation induced by NS11021 and sildenafil in human erectile tissue. NS11021 and sildenafil but not vehicle increased erectile responses in anaesthetized rats, an effect which was abolished after pretreatment with tetraethylammonium.

CONCLUSIONS AND IMPLICATIONS

NS11021 leads to relaxation of both intracavernous arteries and corpus cavernosum strips primarily through opening of BK(Ca) channels. It is also effective in facilitating erectile responses in anaesthetized rats. These results suggest a potential for use of BK(Ca) openers in the treatment of ED.