Androgens and Morphologic Remodeling at Penile and Cardiovascular Levels: A Common Piece in Complicated Puzzles?

Research progress on the protective effect of hormones and hormone drugs in myocardial ischemia-reperfusion injury

Ischemic heart disease (IHD) is a condition where the heart muscle does not receive enough blood flow, leading to cardiac dysfunction. Restoring blood flow to the coronary artery is an effective clinical therapy for myocardial ischemia. This strategy helps lower the size of the myocardial infarction and improves the prognosis of patients. Nevertheless, if the disrupted blood flow to the heart muscle is restored within a specific timeframe, it leads to more severe harm to the previously deprived heart tissue. This condition is referred to as myocardial ischemia/reperfusion injury (MIRI). Until now, there is a dearth of efficacious strategies to prevent and manage MIRI. Hormones are specialized substances that are produced directly into the circulation by endocrine organs or tissues in humans and animals, and they have particular effects on the body. Hormonal medications utilize human or animal hormones as their active components, encompassing sex hormones, adrenaline medications, thyroid hormone medications, and others. While several studies have examined the preventive properties of different endocrine hormones, such as estrogen and hormone analogs, on myocardial injury caused by ischemia-reperfusion, there are other hormone analogs whose mechanisms of action remain unexplained and whose safety cannot be assured. The current study is on hormones and hormone medications, elucidating the mechanism of hormone pharmaceuticals and emphasizing the cardioprotective effects of different endocrine hormones. It aims to provide guidance for the therapeutic use of drugs and offer direction for the examination of MIRI in clinical therapy.

Low androgen levels induce ferroptosis of rat penile cavernous endothelial cells

Background

Endothelial dysfunction caused by low androgen levels in penile tissue can lead to erectile dysfunction. The exact mechanism of endothelial dysfunction has not been thoroughly studied.

Objective

The study sought to verify whether low androgen levels induce ferroptosis of endothelial cells in rat penile tissue.

Methods

Rat penile cavernous endothelial cells (CP-R133) were divided into a no-androgen group (Dihydrotestosterone (DHT): 0 nmol/L), very low-androgen group (DHT: 0.1 nmol/L), low-androgen group (DHT: 1 nmol/L), DHT = 10 nmol/L group, DHT (0 nmol/L) + ferrostatin-1 (Fer-1) group, DHT (0.1 nmol/L) + Fer-1 group, DHT (1 nmol/L) + Fer-1 group, DHT (10 nmol/L) + Fer-1 group. Cell viability, intracellular ferrous ion (Fe2+), malondialdehyde (MDA), GSH into oxidized glutathione (GSSG), reactive oxygen species (ROS), nitric oxide (NO), transferrin receptor 1 protein (TfR1), solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), acyl-CoA synthetase long-chain family member 4 (ACSL4), endothelial nitric oxide synthase (eNOS), and phospho-eNOS (p-eNOS) were detected.

Outcomes

Low androgen levels could induce ferroptosis of rat penile cavernous endothelial cells in vivo by upregulating the expressions of TfR1 and ACSL4 and downregulating the expressions of SLC7A11 and GPX4.

Results

Cell viability, the levels of glutathione (GSH), NO, SLC7A11, GPX4, and p-eNOS/eNOS in the DHT = 0 nmol/L group were lower than those in the other groups (P < .05). The levels of Fe2+, ROS, MDA, GSSG, TfR1, and ACSL4 in the DHT = 0 nmol/L group were higher than those in the other groups (P < .05). Cell viability and the levels of GSH, NO, SLC7A11, GPX4, and p-eNOS/eNOS in the DHT = 1 nmol/L group were lower than those in the DHT (1 nmol/L) + Fer-1 group, DHT = 10 nmol/L group, and DHT (10 nmol/L) + Fer-1 group (P < .05). The levels of Fe2+, ROS, MDA, GSSG, TfR1, and ACSL4 in the DHT = 1 nmol/L group were higher than those in the DHT (1 nmol/L) + Fer-1 group, DHT = 10 nmol/L group, and DHT (10 nmol/L) + Fer-1 group (P < .05).

Clinical Implications

A ferroptosis inhibitor might be a novel drug for treating erectile dysfunction caused by low androgen level.

Strengths and Limitations

The results of this study need to be further confirmed in in vitro and in human studies. Meanwhile, further investigation is needed to clarify whether low androgen levels affect ferroptosis of rat penile cavernous smooth muscle and nerve cells.

Conclusion

Low androgen levels can induce ferroptosis of endothelial cells in rat penile tissue. Inhibition of ferroptosis can reverse endothelial dysfunction caused by low androgen levels.

Cardiovascular/Stroke Risk Assessment in Patients with Erectile Dysfunction-A Role of Carotid Wall Arterial Imaging and Plaque Tissue Characterization Using Artificial Intelligence Paradigm: A Narrative Review

PURPOSE

The role of erectile dysfunction (ED) has recently shown an association with the risk of stroke and coronary heart disease (CHD) via the atherosclerotic pathway. Cardiovascular disease (CVD)/stroke risk has been widely understood with the help of carotid artery disease (CTAD), a surrogate biomarker for CHD. The proposed study emphasizes artificial intelligence-based frameworks such as machine learning (ML) and deep learning (DL) that can accurately predict the severity of CVD/stroke risk using carotid wall arterial imaging in ED patients.

METHODS

Using the PRISMA model, 231 of the best studies were selected. The proposed study mainly consists of two components: (i) the pathophysiology of ED and its link with coronary artery disease (COAD) and CHD in the ED framework and (ii) the ultrasonic-image morphological changes in the carotid arterial walls by quantifying the wall parameters and the characterization of the wall tissue by adapting the ML/DL-based methods, both for the prediction of the severity of CVD risk. The proposed study analyzes the hypothesis that ML/DL can lead to an accurate and early diagnosis of the CVD/stroke risk in ED patients. Our finding suggests that the routine ED patient practice can be amended for ML/DL-based CVD/stroke risk assessment using carotid wall arterial imaging leading to fast, reliable, and accurate CVD/stroke risk stratification.

SUMMARY

We conclude that ML and DL methods are very powerful tools for the characterization of CVD/stroke in patients with varying ED conditions. We anticipate a rapid growth of these tools for early and better CVD/stroke risk management in ED patients.

Low androgen status inhibits erectile function by up-regulating the expression of proteins of mitochondria-associated membranes in rat corpus cavernosum

OBJECTIVE

To investigate the effect of low androgen status on mitochondria-associated membranes (MAMs) and its relationship with erectile function.

METHODS

A total of 36 eight-week-old male Sprague-Dawley rats were randomly divided into 6 groups: the control (sham-operated) group, the castration group, the castration + testosterone (cast + T) group, the control + siRNA group, the cast + siRNA group, and the cast + empty vector group. Testosterone propionate (3 mg/kg) was subcutaneously injected into the rats in the cast + T group every other day starting from the second day after the surgery. Four weeks later, lentiviral vectors carrying phosphofurin acidic cluster sorting protein 2 (PACS-2) gene-specific siRNA (1 × 10⁸ TU/ mL, 10 μL) were injected into the rats in the siRNA groups. At the 6th week of castration, the ratio of the maximum intracavernous pressure/the mean arterial pressure (ICPmax/MAP), the levels of nitric oxide (NO), endothelial nitric oxide synthase (eNOS), phospho-eNOS (p-eNOS), fatty acid-CoA ligase 4 (FACL-4), PACS-2, and inositol 1,4,5-trisphosphate receptor type 1 (IP3R1) in the penile corpus cavernosum were determined.

RESULTS

The FACL-4, PACS-2 and IP3R1 were primarily localized in the cytoplasm of endothelial cells and part of smooth muscle cells in the corpus cavernosum. The level of NO, the ratio of ICPmax/MAP, and p-eNOS/eNOS were decreased significantly in the castration group compared with the control group (P<0.01). The expressions of FACL-4, PACS-2, and IP3R1 were increased significantly in the castration group compared with the control group (P<0.01). The level of NO, the ratios of ICPmax/MAP, and the ratio of p-eNOS/eNOS were increased significantly in the cast + siRNA group compared with the castration group (P<0.01). The expressions of FACL-4 and PACS-2 were decreased significantly in the cast + siRNA group compared with the castration group (P<0.01).

CONCLUSION

Low androgen status up-regulated the expressions of patients in MAMs (FACL-4, PACS-2 and IP3R1) in the corpus cavernosum and inhibited the eNOS/NO/cGMP signaling pathway, resulting in impaired erectile function in rats. Erectile function may be improved by inhibiting the high expression of PACS-2 in the corpus cavernosum under low androgen state. This article is protected by copyright. All rights reserved.

Retrospection of Analytical Data Collected through Smart Devices for Diseases and Disability Caused by Physical Inactivity

The basic meaning of inactive lifestyle is doing sedentary activities. This includes playing video games, watching TV, operating computers, and sitting in a particular place for a long time. It may be sitting on the train or in bus, car, or office. This has many adverse effects on our bodies. This paper emphasizes the importance of physical activity, and a case study is presented to support the hypothesis that physical activity can certainly help improve human health. The diseases caused by inactive life are discussed in our paper. In this paper, a case study is described in which 200 individuals have participated in an activity called "Activity is Life," with the goal of improving the sedentary lifestyle and getting rid of physical ailments. The usage of analytical tools is made to analyse the data collected from the empirical research study, and IoT-based smart devices are used to capture the runtime data. The physicians and nurses have odd working hours, they have to go through many stress-induced situations, and most of them are suffering from life-threatening diseases such as depression, hypertension, cancer, and cardiovascular diseases. The main reason is inactivity in their lifestyles. To carry out an experimental study and to see the impact of regular activities on the health of doctors and nurses, a program was designed where 200 participants have participated. It is found that the activity-based 30-day program yielded great health benefits, including reduction in stress level, improvement in sleep quality index, and improvement in blood pressure values.

Low androgen status inhibits erectile function by increasing pyroptosis in rat corpus cavernosum

BACKGROUND

The mechanism of erectile dysfunction (ED) caused by low androgen status is not fully understood.

OBJECTIVES

To investigate whether low androgen status inhibits erectile function of rats by inducing pyroptosis in the corpus cavernosum (CC).

MATERIALS AND METHODS

Thirty-six eight-weeks-old healthy male Sprague-Dawley rats were equally divided into six groups: sham-operated group (4w sham, 8w sham), castration group (4w cast, 8w cast), and castration + testosterone (T) group (4w cast + T, 8w cast + T). The rats in castration + T groups were injected with testosterone propionate subcutaneously every other day. After 4 and 8 weeks, the ratio of maximum intracavernous pressure (ICPmax)/mean arterial pressure (MAP), the level of serum T, the concentration of nitric oxide (NO) and interleukin-1β (IL-1β), the expression of NOD-like receptor pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC), Caspase-1 p20, gasdermin D-N (GSDMD-N), transforming growth factor β1 (TGF-β1), collagen-I, and collagen-III, the ratio of smooth muscle/collagen (SM/C), and the proportion of pyroptotic cells in the CC were analyzed.

RESULTS

The ratio of ICPmax/MAP (3/5 V) and SM/C, the level of NO and serum T was significantly decreased in castration groups when compared to other groups (p < 0.01). NLRP3, ASC, Caspase-1, and GSDMD were mainly expressed in the cytoplasm of smooth muscle cells (SMCs) and endothelial cells (ECs) in the CC. The expression of NLRP3, ASC, Caspase-1p20, GSDMD-N, IL-1β, TGF-β1, collagen-I, and collagen-III was significantly increased in castration groups when compared with other groups (p < 0.01). The proportion of pyroptotic cells in the CC was increased significantly in castration groups when compared with other groups (p < 0.05).

DISCUSSION AND CONCLUSION

Low androgen status inhibits erectile function of rats by promoting CC fibrosis and reducing NO synthesis through pyroptosis of SMCs and ECs in the CC.

Understanding Erectile Dysfunction in Hypertensive Patients: The Need for Good Patient Management

Erectile dysfunction (ED) is defined as a man’s consistent or recurrent inability to attain and/or maintain penile erection enough for successful vaginal intercourse. ED affects a large part of the population, increasing its incidence with age and comorbidities. It is estimated by the year 2025, 322 million men will suffer from ED. Incidence of ED has been related not only to chronic diseases such as diabetes mellitus, metabolic syndrome, hyperlipidemia, psychiatric diseases or urinary tract diseases, but also to hypertension and especially to antihypertensive treatments. This review summarizes current knowledge about the management of ED in hypertensive men and its role as cardiovascular disease predictor.

Association Between Erectile Dysfunction and Carotid Subclinical Atherosclerosis in HIV-Infected Patients

BACKGROUND

Erectile dysfunction (ED) is frequent in HIV-infected patients, and it can be associated with atherosclerosis and cardiovascular events. So, the objective was to evaluate whether the presence of moderate-severe ED was a marker of subclinical atherosclerosis (SCA) in HIV-infected patients.

METHODS

A cross-sectional study was conducted in a cohort of HIV-infected patients. The presence of ED was assessed using the International Index of Erectile Function (IIEF-5) questionnaire. The presence of SCA was determined by calculating the mean carotid intima-media thickness with Doppler ultrasound. A logistic regression analysis was performed to check the variables associated with SCA.

RESULTS

One hundred thirty-nine men of 45 (10) years of age were included, of which 130 (94.9%) received antiretroviral therapy. In 30 (22%) patients, the Framingham score was higher than 10%. In 36 (25.9%) patients, ED was detected in a moderate-severe degree and in 53 (38.1%), SCA was detected. In the multivariate analysis, variables independently associated with the presence of SCA were as follows: older age [odds ratio (OR) = 1.22, confidence interval (CI) 95%: 1.1 to 1.35, P < 0.001] and moderate-severe ED (OR = 4.68, CI 95%: 1.18 to 18.5; P = 0.028). Variables associated with moderate-severe ED were as follows: age (OR = 1.107, CI 95%: 1.041 to 1.17, P < 0.001) and having antibodies for hepatitis C virus (OR = 5.12, CI 95%: 1.54 to 17.03, P < 0.001).

CONCLUSIONS

HIV-Infected patients often have moderate-severe ED, especially the elderly and coinfected patients with hepatitis C virus. ED can be an early clinical manifestation of incipient atherosclerosis, so its presence should involve a deep control of cardiovascular risk factors and using a regimen with a better atherogenic profile.

The correlation between erectile dysfunction and metabolic syndrome in an Indian population: A cross-sectional observational study

Objective: To evaluate the relationship between erectile dysfunction (ED), based on the five-item International Index of Erectile Function questionnaire (IIEF-5), and presence of metabolic syndrome (MetS) or its components based on Adult Treatment Panel III guidelines. We also explored the impact of increasing insulin resistance (IR), as calculated using the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) equation, on severity of ED. Pathophysiological links between ED and testosterone were re-evaluated.

Patients and methods: In all, 357 patients with ED were evaluated; 53 patients with primary, psychogenic, surgical, post-traumatic or drug-induced ED were excluded. The remaining 304 patients were evaluated after obtaining written informed consent. The Institutional Review Board approved the study. We assessed comorbidities, IIEF-5 scores, lower urinary tract symptoms (LUTS) based on International Prostate Symptom Score (IPSS), blood sugars, lipid and hormonal profiles, and vitamin D3 levels. Further evaluation was done when indicated.

Results: In all, 171 patients had MetS and 134 had pre-existing comorbidities (diabetes mellitus, 58; hypertension, 73; coronary artery disease, 13). The mean (SD) age was 44.6 (9.21) years and IIEF-5 score was 13.81 (3.17). ED severity was significantly correlated with presence of MetS. On multivariate analysis, there were significant correlations between ED and waist circumference, serum triglycerides, and fasting blood sugar. There was a statistically significant positive correlation between serum testosterone and IIEF-5 score (r = +0.292). The mean (SD) IR value (using the HOMA-IR formula) was 2.64 (2.87), which was statistically and negatively correlated with IIEF-5 scores (r = – 0.398). Receiver operating characteristic analysis showed that an IIEF-5 score of <14 predicted MetS and a HOMA-IR value of >2.1778 predicted MetS.

Conclusion: MetS or its components were present in 56.25% of the patients. Therefore presence of ED merits further evaluation for presence of MetS. This may help to prevent catastrophic and life-threatening consequences of MetS.

Abbreviations: BMI: body mass index; CRP: C-reactive protein; CVD: cardiovascular disease; DBP: diastolic blood pressure; DM: diabetes mellitus; ED: erectile dysfunction; FBS: fasting blood sugar; HDL: high-density lipoprotein; HOMA-IR- Homeostatic Model Assessment for Insulin Resistance; HTN: hypertension; IIEF-5: five-item version of the International Index of Erectile Function; IR: insulin resistance; LDL: low-density lipoprotein; LUTS: lower Urinary Tract Symptoms; MetS: metabolic syndrome; NO: nitric oxide; OR: odds ratio; PPBS: post-prandial blood sugar; ROC: receiver operating characteristic; SBP: systolic blood pressure; TG: triglyceride; WC: waist circumference

Deterioration of Chronotropic Responses and Heart Rate Recovery Indices in Men With Erectile Dysfunction

Introduction

Erectile dysfunction (ED) and cardiovascular (CV) diseases share common risk factors and ED has been accepted as an early manifestation of CV disease. Exercise stress testing (EST) is used to evaluate CV functions in men with ED. Low exercise workload, a slower heart rate recovery (HRR) after exercise, and inability to increase heart rate during EST (chronotropic incompetence) are independent negative predictors of adverse CV outcomes.

Aim

To assess the association among EST parameters, ED, and testosterone levels.

Methods

The study population consisted of 41 patients with ED and 40 controls. All participants underwent treadmill EST to assess cardiac autonomic functions. HRR indices were calculated by subtracting 1st (HRR1), 2nd (HRR2), and 3rd (HRR3) minute heart rates during the recovery period from maximal heart rate. Total exercise duration, exercise capacity and chronotropic response, and plasma testosterone levels were evaluated. Erectile functions were evaluated with the Sexual Health Inventory for Men. Patients were divided into subgroups according to severity and duration of ED.

Main Outcome Measures

Mean HRR1 (30.6 ± 11.9 vs 36.9 ± 9.9; P = .01), HRR2 (44.9 ± 12.4 vs 54.9 ± 7.8; P < .001), and HRR3 (50.1 ± 11.7 vs 63.0 ± 7.9; P < .001) were significantly lower in the ED than in the control group. Total exercise duration (9.4 ± 1.9 vs 10.9 ± 1.7 minutes; P < .001), exercise capacity (12.5 ± 1.9 vs 13.6 ± 1.4 metabolic equivalents; P = .004), and chronotropic response (0.88 ± 0.1 vs 1.0 ± 0.1; P < .001) were worse in the ED group. However, we found no association between severity and duration of ED and EST parameters. In addition, serum testosterone levels were significantly correlated with HRR1 (r = 0.36, P = .02) in men with ED.

Conclusion

Our data suggested that cardiac autonomic functions are impaired in patients with ED. A weak correlation between cardiac autonomic dysfunction and low testosterone levels in patients with ED was noted. However, further studies are needed to elucidate the prognostic significance and clinical implications of impaired autonomic functions and testosterone replacement therapy in patients with ED.

Kucukdurmaz F, Agar G, Resim S. Deterioration of Chronotropic Responses and Heart Rate Recovery Indices in Men With Erectile Dysfunction. Sex Med 2018;6:8–14.

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.

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.

Lack of exercise is a major cause of chronic diseases

Chronic diseases are major killers in the modern era. Physical inactivity is a primary cause of most chronic diseases. The initial third of the article considers: activity and prevention definitions; historical evidence showing physical inactivity is detrimental to health and normal organ functional capacities; cause versus treatment; physical activity and inactivity mechanisms differ; gene-environment interaction (including aerobic training adaptations, personalized medicine, and co-twin physical activity); and specificity of adaptations to type of training. Next, physical activity/exercise is examined as primary prevention against 35 chronic conditions [accelerated biological aging/premature death, low cardiorespiratory fitness (VO2max), sarcopenia, metabolic syndrome, obesity, insulin resistance, prediabetes, type 2 diabetes, nonalcoholic fatty liver disease, coronary heart disease, peripheral artery disease, hypertension, stroke, congestive heart failure, endothelial dysfunction, arterial dyslipidemia, hemostasis, deep vein thrombosis, cognitive dysfunction, depression and anxiety, osteoporosis, osteoarthritis, balance, bone fracture/falls, rheumatoid arthritis, colon cancer, breast cancer, endometrial cancer, gestational diabetes, pre-eclampsia, polycystic ovary syndrome, erectile dysfunction, pain, diverticulitis, constipation, and gallbladder diseases]. The article ends with consideration of deterioration of risk factors in longer-term sedentary groups; clinical consequences of inactive childhood/adolescence; and public policy. In summary, the body rapidly maladapts to insufficient physical activity, and if continued, results in substantial decreases in both total and quality years of life. Taken together, conclusive evidence exists that physical inactivity is one important cause of most chronic diseases. In addition, physical activity primarily prevents, or delays, chronic diseases, implying that chronic disease need not be an inevitable outcome during life.

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.

Endothelial progenitor cells and erectile dysfunction: a brief review on diagnostic significance and summary of our experience

The article provides a brief review of the literature concerning the diagnostic use of endothelial progenitor cells in patients with erectile dysfunction. In particular, patients with arterial erectile dysfunction could benefit from the use of this diagnostic marker, which in clinical practice can be used together with more conventional methods such as the penile Doppler. It is very important to acquire diagnostic tools for the diagnosis of sub clinical form of endothelial dysfunction in these patients, in particular when the erectile dysfunction is associated with cardiovascular risk factors.

Different profile of endothelial cell apoptosis in patients with Klinefelter's syndrome

INTRODUCTION

The aim of this study was to evaluate the effects of testosterone (T) therapy on the sexual function of middle-aged patients with acquired pre-pubertal hypergonadotropic hypogonadism (HrHy) and patients with Klinefelter syndrome (KS).

PATIENTS AND METHODS

A selected series of 35 middle-aged hypogonadal patients, including those who had recently been observed during andrological counseling (extracted from our database) and had not yet begun hormonal treatment, was recruited for this evaluation. This series of patients included 20 patients with acquired prepubertal HrHy and 15 KS patients who were matched by age and body mass index. All patients underwent an andrological evaluation, which included the administration of the International Index of Erectile Function 5 (IIEF-5) questionnaire and the evaluation of penile echo color Doppler. In addition, by flow cytometry we evaluated the serum levels of apoptotic endothelial microparticles (EMPa) and the vitronectin receptor (VR) at baseline and 6 months after the onset of T therapy.

RESULTS

After 6 months of T therapy, patients with HrHy demonstrated mean IIEF-5 scores and a peak systolic velocity that were significantly greater and a mean acceleration time that was significantly lower (p<0.05) than those of patients with KS (p<0.05). In addition, patients with HrHy showed mean EMPa values and VR serum concentrations that were significantly lower than those of patients with KS (p<0.05). KS patients showed significantly improved IIEF-5 scores and Doppler parameters (p<0.05) but not EMPa or VR serum concentrations following treatment.

DISCUSSION

These results indicate that erectile dysfunction in KS can improve with T therapy, although this improvement is more profound in HrHy patients, and these results also suggest that T therapy does not improve the severity of endothelial cell apoptosis in KS patients.

Androgen depletion in humans leads to cavernous tissue reorganization and upregulation of Sirt1-eNOS axis

Aging and physiological androgen decay leads to structural changes in corpus cavernosum (CC) that associate with erectile function impairment. There is evidence that such changes relate to nitric oxide (NO) bioavailability, an endothelial compound produced by the action of endothelial NO synthase (eNOS), and is regulated by sirtuin-1 (Sirt1), a NAD(+)-dependent protein deacetylase. Taking into account the reduced NO synthesis observed in aging and erectile dysfunction, we aimed to characterize human CC of androgen-deprived, young, and aged individuals postulating that androgen deprivation induces modifications similar to those observed in aging. Human penile fragments were collected from young individuals submitted to male-to-female sex reassignment procedure, who undergone an androgen deprivation chemical regimen, from young organ donors and from aged patients submitted to penile deviation surgery. They were processed for histomorphometric analysis of smooth muscle (SM) and connective tissues (CT), and dual-immunofluorescence of alpha-actin/vWf or Sirt1, and endothelin-1/eNOS. Estrogen receptors were analyzed by immunohistochemistry and semiquantification of Sirt1, eNOS, and phospho-Akt was assayed by Western blotting. Androgen withdrawal, similarly to aging, leads to a noteworthy reduction of SM-to-CT ratio in CC. However, in contrast to young and aged, a significant increase in penile Sirt1 expression accompanied by an increase in total eNOS expression was observed in androgen-depleted individuals. No changes were evidenced in phospho-Akt system and estrogen receptors were undetectable. These findings indicate that Sirt1 regulates the expression of eNOS in human CC employing mechanisms influenced by androgen depletion.

Cellular actions of testosterone in vascular cells: mechanism independent of aromatization to estradiol

In this work we investigated the role of testosterone on cellular processes involved in vascular disease, and whether these effects depend on its local conversion to estradiol. Cultures of rat aortic endothelial and smooth muscle cells in vitro treated with physiological concentrations of testosterone were employed. Testosterone rapidly increased endothelial nitric oxide production. To evaluate whether this non genomic action was dependent on testosterone aromatization we used an aromatase inhibitor. Anastrozole compound did not modify the fast increase in nitric oxide production elicited by testosterone. The hormonal effect was completely blocked by an androgen receptor antagonist (flutamide); meanwhile it wasn't modified by the presence of an estrogen receptor antagonist (ICI182780).The possibility of intracellular estradiol synthesis was ruled out when no differences were found in estradiol measurements performed in culture incubation medium from control and testosterone treated cells. The 5α-reductase inhibitor finasteride partially suppressed the enhancement in nitric oxide production, suggesting that the effect of testosterone was partially due to dihydrotestosterone conversion. Testosterone stimulated muscle cell proliferation independent of local conversion to estradiol. When cellular events that play key roles in vascular disease development were analyzed, testosterone prevented monocyte adhesion to endothelial cells induced by a proinflammatory stimulus (bacterial lipopolysaccharides), and prompted muscle cell migration in presence of a cell motility inducer. In summary, testosterone modulates vascular behavior through its direct action on vascular cells independent of aromatization to estradiol. The cellular actions exhibited by the steroid varied whether cells were under basal or inflammatory conditions.

Testosterone, endothelial health, and erectile function

Experimental and clinical studies have reported that testosterone has a critical role in the maintenance of homeostatic and morphologic corpus cavernosum components, essential for normal erectile physiology. Although the exact mechanisms mediated by testosterone in erectile function are still under investigation, recent research has suggested an important role in the regulation of endothelial cell (EC) biological functions. Besides stimulating the production of EC mediators, testosterone is also thought to promote the vasculogenic reendothelialization process, mediated by bone marrow-derived endothelial progenitor cells. Additionally, testosterone seems to modulate other erectile tissue components, including trabecular smooth muscle cells, nerve fibers, and tunica albuginea structure, all essential for the erectile process. This paper summarizes current data regarding testosterone-induced cellular and molecular mechanisms that regulate penile tissue components, focusing particularly on the role of testosterone in endothelial health and erectile function.

Erectile tissue molecular alterations with aging: differential activation of the p42/44 MAP Kinase pathway

Erectile dysfunction (ED) is a common problem in aged men; however, the molecular events involved in aging ED remain unclear. To better characterize the effects of aging in the penis, we evaluated cavernosal tissue remodeling capability and the downstream activation of the intracellular signaling mediator mitogen-activated protein p42/44 kinase (p42/44 MAPK). We used male Wistar rats, which were divided in groups of 2, 6, 12, 18, and 24 months old. Penile tissues were harvested and processed for protein isolation and immunohistochemical analysis. Cavernosal viability was assessed by TUNEL assay, and proliferation was analyzed by immunohistochemical detection of proliferating cell nuclear antigen (PCNA). Immunolocalization of the activated form of p42/44 MAPK was evaluated by immunofluorescence, and changes in its phosphorylation status were quantified by western blotting. p42/44 phosphorylation profile was also assessed in situ in human young and elderly cavernosal samples. With the advancement of age, experimental cavernosal tissue remodeling was affected by an age-dependent unbalance between the rate of apoptosis and proliferation, in all erectile components. Moreover, this turnover alteration was accompanied by significant modifications in the activation profile of the downstream effector p42/44 MAPK. In the youngest corporeal samples, p42/44 was mostly activated at perivascular sites, potentially mediating cell survival/proliferation. However, in elderly experimental erectile tissue, p42/44 phosphorylation shifted to trabecular fibroblasts, indicating a potential role in extracellular matrix (ECM) production. More importantly, the same differential pattern of p42/44 activation was observed in human young and aged cavernosal fragments, suggesting a distinct function of this protein with aging. We provided evidence for the first time that with the advancement of age, there is a differential activation of p42/44 MAPK in cavernosal tissue, which may promote ECM expansion and fibrosis, therefore compromising erectile function in the elderly.