Diabetes, hypertension and erectile dysfunction

Diabetes-induced male infertility: potential mechanisms and treatment options

Male infertility is a physiological phenomenon in which a man is unable to impregnate a fertile woman during a 12-month period of continuous, unprotected sexual intercourse. A growing body of clinical and epidemiological evidence indicates that the increasing incidence of male reproductive problems, especially infertility, shows a very similar trend to the incidence of diabetes within the same age range. In addition, a large number of previous in vivo and in vitro experiments have also suggested that the complex pathophysiological changes caused by diabetes may induce male infertility in multiple aspects, including hypothalamic-pituitary-gonadal axis dysfunction, spermatogenesis and maturation disorders, testicular interstitial cell damage erectile dysfunction. Based on the above related mechanisms, a large number of studies have focused on the potential therapeutic association between diabetes progression and infertility in patients with diabetes and infertility, providing important clues for the treatment of this population. In this paper, we summarized the research results of the effects of diabetes on male reproductive function in recent 5 years, elaborated the potential pathophysiological mechanisms of male infertility induced by diabetes, and reviewed and prospected the therapeutic measures.

Peyronie's disease development and management in diabetic men

BACKGROUND

Peyronie's disease (PD) is a fibrosing disorder of the penis resulting in plaque formation and penile deformity that negatively affect sexual and psychosocial function of patients. A multifactorial etiology of PD is assumed with diabetes mellitus (DM) being a potential risk factor.

OBJECTIVES

The aim of this narrative review was to investigate diabetes role in PD pathophysiology, diagnosis, and treatment.

MATERIALS AND METHODS

A non-systematic narrative review of original articles, meta-analyses, and randomized trials was conducted, including articles in the pre-clinical setting to support relevant findings.

RESULTS

Diabetes is one of the most common comorbidity observed in PD patients, with a prevalence of about 11% and a strong association with erectile dysfunction (ED). DM is associated with both a higher risk of developing PD and has also an impact on the outcomes of PD's treatments.

DISCUSSION

Evidence from literature underlines that metabolic alterations typical of DM are pivotal factors in the development of PD and resistance to its medical treatment.

CONCLUSION

The role of DM in development of PD is still debated, while its role in PD development is not completely clear, there is a clear impact of DM on PD treatment outcomes.

Ca2+ -activated Cl- channels (TMEM16A) underlie spontaneous electrical activity in isolated mouse corpus cavernosum smooth muscle cells

Penile detumescence is maintained by tonic contraction of corpus cavernosum smooth muscle cells (CCSMC), but the underlying mechanisms have not been fully elucidated. The purpose of this study was to characterize the mechanisms underlying activation of TMEM16A Ca2+ -activated Cl- channels in freshly isolated murine CCSMC. Male C57BL/6 mice aged 10-18 weeks were euthanized via intraperitoneal injection of sodium pentobarbital (100 mg.kg-1 ). Whole-cell patch clamp, pharmacological, and immunocytochemical experiments were performed on isolated CCSM. Tension measurements were performed in whole tissue. TMEM16A expression in murine corpus cavernosum was confirmed using immunocytochemistry. Isolated CCSMC developed spontaneous transient inward currents (STICs) under voltage clamp and spontaneous transient depolarizations (STDs) in current clamp mode of the whole cell, perforated patch clamp technique. STICs reversed close to the predicted Cl- equilibrium potential and both STICs and STDs were blocked by the TMEM16A channel blockers, Ani9 and CaCC(inh)-A01. These events were also blocked by GSK7975A (ORAI inhibitor), cyclopiazonic acid (CPA, sarcoplasmic reticulum [SR] Ca2+- ATPase blocker), tetracaine (RyR blocker), and 2APB (IP3 R blocker), suggesting that they were dependent on Ca2+ release from intracellular Ca2+ stores. Nifedipine (L-type Ca2+ channel blocker) did not affect STICs, but reduced the duration of STDs. Phenylephrine induced transient depolarizations and transient inward currents which were blocked by Ani9. Similarly, phenylephrine induced phasic contractions of intact corpus cavernosum muscle strips and these events were also inhibited by Ani9. This study suggests that contraction of CCSM is regulated by activation of TMEM16A channels and therefore inhibition of these channels could lead to penile erection.

Diabetes mellitus and the impairment of male reproductive function: Possible signaling pathways

BACKGROUND AND AIMS

Today, it has been shown that diabetes mellitus (DM) can affect male fertility. Glucose metabolism is a vital process in spermatogenesis that is impacted by diabetes condition. But the mechanisms by which DM causes male infertility are not wholly clarified. The aim of this review is to provide brief information about the influence of hyperglycemia on male fertility and specific emphasis on the molecular signaling pathway that is involved.

METHODS

Broad literature search in the electronic database "Pubmed", "Google Scholar", the website of "World Health Organization" (WHO) and Control Disease and Prevention (CDC) took place. There was no time restriction. A key criterion for the selection of articles was English and language. Finally, one hundred thirty seven articles were included in the review.

RESULTS

Diabetes mellitus affects many signaling pathways that involved in the spermatogenesis. It seems that increased ROS and oxidative stress in the diabetes is the beginning of all fertility problems and affects all of involved signaling pathways in the spermatogenesis.

CONCLUSIONS

It seems that there was strong interconnected between oxidative stress and all of involved signaling pathways in the reproductive problems in diabetes. So, approaches that diminish oxidative stress in the testis can be effective in improving diabetes related infertility complications.

Hypertension might be a risk factor for erectile dysfunction: a meta-analysis

The study aimed to evaluate whether hypertension was a risk factor for erectile dysfunction (ED). Databases including PubMed and Embase were retrieved to identify studies related to hypertension in ED patients. Odds ratio (OR) and 95% confidence interval (CI) were used as the effect size. Subgroup analyses stratified by total number of enrolled subjects and research regions were performed. Sensitivity analysis was performed by removing a single study at one time. Egger's test was used to evaluate the publication bias. Totally, 40 studies including 121,641 subjects were included in the meta-analysis. As a result, hypertension was closely related to ED (OR = 1.74, 95% CI, 0.63-0.80, p < .01). Subgroup analysis indicated hypertension was the risk factor for ED whatever the participants numbers. When stratified by different regions, hypertension was a risk factor for ED in Africa (OR = 3.35, 95% CI, 1.45-7.77, p < .01), Americas (OR = 1.97, 95% CI, 1.68-2.31, p < 0.01), Asia (OR = 1.46, 95% CI, 1.16-1.84, p < .01) and Europe (OR = 1.83, 95% CI, 1.34-2.49, p < .01), but not in Australia. Hypertension may be a potential risk factor for ED.

The impact of poor glycaemic control on the prevalence of erectile dysfunction in men with type 2 diabetes mellitus: a systematic review

Objective

To determine the impact of poor glycaemic control on the prevalence of erectile dysfunction among men with type 2 Diabetics aged 27 to 85 years.

Design

The databases Embase classic+Embase, Global health, Ovid Medline and PsychINFO, were searched for relevant studies in June 2014 using the keywords: (Diabetes Mellitus OR diabetes mellitus type2 OR DM2 OR T2DM OR insulin resistance) AND (erectile dysfunction OR sexual dysfunction OR impotence) AND glycaemic control.

Setting

All study settings were considered (primary care, secondary care and tertiary care setting).

Participants

Type 2 Diabetic Patients with erectile dysfunction.

Main outcome measures

Included studies must include one of the following outcomes: (1) HBA1c for assess the level of glycaemic control; (2) Erectile dysfunction (any stage: IIEF-5 = 21 or less).

Results

Five cross-sectional studies involving 3299 patients were included. The findings pointed to a positive association between erectile dysfunction and glycaemic control. Three studies showed a significant positive association, while one study showed only a weak correlation and one study showed borderline significance. Patients’ age, diabetes mellitus duration, peripheral neuropathy and body mass index had positive association with erectile dysfunction. However, smoking and hypertension were not associated with erectile dysfunction in most included studies. Physical activity had a protective effect against erectile dysfunction.

Conclusion

We may conclude that the risk of erectile dysfunction is higher in type 2 diabetic men with poor glycaemic control than those with good control.

The effect of Qigong on menopausal symptoms and quality of sleep for perimenopausal women: a preliminary observational study

OBJECTIVES

The study objectives were to examine the effect of a 12-week 30-minute-a-day Ping Shuai Qigong exercise program on climacteric symptoms and sleep quality in perimenopausal women.

DESIGN

This was a prospective observational study.

SETTINGS/LOCATION

The subjects (N=70) from two communities were women aged 45 years and above who were experiencing menopausal symptoms.

SUBJECTS

Thirty-five (35) women from one community were assigned to a Ping Shuai Qigong intervention group, while 35 women from the other community were assigned to the control group.

INTERVENTIONS

This was a 12-week, 30-minute-a-day Ping Shuai Qigong program.

OUTCOME MEASURES

The Greene Climacteric Symptom scale and the Pittsburgh Sleep Quality Index were the outcome measures.

METHODS

Descriptive analysis and repeated-measures analysis of variance were used.

RESULTS

Pretest scores at baseline found no significant group differences in climacteric symptoms or sleep quality. Significant improvements in climacteric symptoms were found at 6 weeks and 12 weeks (t=4.07, p<0.001 and t=11.83, p<0.001) in the intervention group. They were also found to have significant improvements in sleep quality in those times (t=5.93, p<0.001 and t=10.58, p<0.001, respectively).

CONCLUSIONS

Ping Shuai Qigong improved climacteric symptoms and sleep quality in perimenopausal women at 6 weeks and 12 weeks. The longer a person practiced this form of meditative exercise, the greater the improvement in sleeping quality and climacteric symptoms.

Intracavernous delivery of synthetic angiopoietin-1 protein as a novel therapeutic strategy for erectile dysfunction in the type II diabetic db/db mouse

INTRODUCTION

Patients with erectile dysfunction (ED) associated with type II diabetes often have impaired endothelial function and tend to respond poorly to oral phosphodiesterase type 5 inhibitors. Therefore, neovascularization is a promising strategy for curing diabetic ED.

AIM

To determine the effectiveness of a soluble, stable, and potent angiopoietin-1 (Ang1) variant, cartilage oligomeric matrix protein (COMP)-Ang1, in promoting cavernous angiogenesis and erectile function in a mouse model of type II diabetic ED. Methods.  Sixteen-week-old male db/db mice (in which obesity and type II diabetes are caused by a mutation in the leptin receptor) and control C57BL/6J mice were used and divided into four groups (N=14 per group): age-matched controls; db/db mice receiving two successive intracavernous injections of phosphate-buffered saline (PBS) (days -3 and 0; 20 µL); db/db mice receiving a single intracavernous injection of COMP-Ang1 protein (day 0; 5.8 µg/20 µL); and db/db mice receiving two successive intracavernous injections of COMP-Ang1 protein (days -3 and 0; 5.8 µg/20 µL).

MAIN OUTCOME MEASURES

Two weeks later, erectile function was measured by electrical stimulation of the cavernous nerve. The penis was then harvested and stained with antibodies to platelet/endothelial cell adhesion molecule-1 (PECAM-1) (endothelial cell marker), phosphohistone H3 (PH3, a nuclear protein indicative of cell proliferation), phospho-endothelial nitric oxide synthase (eNOS), and eNOS. Penis specimens from a separate group of animals were used for cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) quantification.

RESULTS

Local delivery of COMP-Ang1 protein significantly increased eNOS phosphorylation and cGMP and cAMP expression compared with that in the group treated with PBS. Repeated intracavernous injections of COMP-Ang1 protein completely restored erectile function and cavernous endothelial content through enhanced cavernous neoangiogenesis as evaluated by PECAM-1 and PH3 immunohistochemistry and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling assay, whereas a single injection of COMP-Ang1 protein elicited partial improvement.

CONCLUSION

Cavernous neovascularization using recombinant Ang1 protein is a novel therapeutic strategy for the treatment of ED resulting from type II diabetes.

Association between erectile dysfunction and cardiovascular risk in individuals with type-2 diabetes without overt cardiovascular disease

BACKGROUND

Erectile dysfunction in type-2 diabetes may be an independent marker for coronary artery disease. Present study was undertaken to investigate whether type-2 diabetic patients with erectile dysfunction without having overt cardiovascular disease had increased cardiovascular risk.

AIM

To find out correlation between ED and cardiovascular risk in diabetic patients.

METHODS

Fifty type-2 diabetic patients were assessed for erectile dysfunction using international index of erectile dysfunction (IIEF-5), which include questionnaire and cardiovascular risk assessment by multiparameter cardiovascular analysis device (periscope).

RESULTS

The prevalence of erectile dysfunction in type-2 diabetics was very high (78%), mild, moderate and severe ED was present in 6, 36 and 36%, respectively. The total cardiovascular risk was more in patients with ED in comparison to patients without ED (34.87 +/- 18.82 vs 20.91 +/- 11.03 p = 0.002). The mean 10-years coronary risk and cardiac risk was 12.00 + 9.60 and 22.23 + 14.14 (p = 0.029) and 13.36 +/- 1.22 and 28.85 +/- 4.13 (p 0.002) in patients without ED and with ED respectively. The mean vascular and atherosclerosis risk was 28.73 +/- 13.94 and 39.38 +/- 19.51 (p > 0.05) and 26.18 +/- 10.31 and 33.92 +/- 13.40 (p > 0.05) in patients without ED and with ED, respectively. Total cardiovascular risk was found to increase with age, duration of diabetes and HbA1c levels.

CONCLUSION

The total cardiovascular risk increases with increasing severity of erectile dysfunction in type-2 diabetic patients without having overt cardiovascular disease.

The hidden impact of diabetes on male sexual dysfunction and fertility

Diabetes affects an increasingly large number of young men of reproductive age. Erectile and ejaculatory difficulties arise due to vascular and neuropathic problems. The treatment of these may have effects on fertility potential. Erectile dysfunction can be treated with mechanical devices and intracavernosal injections. Although these have not been shown to affect fertility directly, they may result in poor compliance and hence reduced frequency of ejaculation with subsequent deterioration in sperm quality. Other medical treatments may have a more direct effect. The phosphodiesterase (PDE) inhibitor pentoxifylline has been shown to affect sperm quality and early embryo development. Therefore, Viagra, also a PDE inhibitor, may affect sperm quality. There is conflicting evidence about this in the literature. Ejaculatory difficulties are also more common in diabetics although treatments such as Trucut testicular biopsy and intracytoplasmic sperm injection have improved the outlook for these patients. There is also some evidence that spermatogenesis is affected by diabetes and that patients have a reduced sperm motility and semen volume. Therefore, diabetes has a significant impact on the fertility of men with this disease both directly and indirectly. The extent of iatrogenic influence on the reduced fertility potential of these patients needs to be researched as a matter of urgency.

Sexual rehabilitation with intracavernous PGE1 injections and oral drug administration in diabetic patients non-responder to oral therapy alone

Diabetes is an important risk factor in erectile dysfunction (ED), acting via several mechanisms. We assessed the efficacy of intracavernous injections (ICI) rehabilitation and oral systematic therapy in diabetic patients, as well as the response of controls to oral therapy ‘on demand’.

Materials and Methods

Sixteen diabetic patients with ED were treated with vasoactive drugs orally when needed, without satisfactory erections. The patients underwent then ICI rehabilitation with PGE1 20 mcg twice weekly for 4 weeks, followed by the administration of oral drugs twice weekly for 4 weeks. Before and after rehabilitation, the patients completed a detailed anamnestic protocol to study their libido (always present); they answered questions Q3 and Q4 of the IIEF questionnaire. During ICI, a study with dynamic echocolordoppler (ECCD) was carried out. All patients had Type 2 diabetes: 10 were treated with oral antidiabetics, 4 were treated with insulin, and in the other 2 patients, treated with insulin, a sensitive neuropathy of the lower limbs was diagnosed. Fourteen patients were treated with antihypertensive drugs.

Results

Before rehabilitation, the mean responses to questions 3 and 4 of the IIEF (International Index of Erectile Function) questionnaire were 1.6 and 1.5 respectively; after rehabilitation, the mean responses were 2.68 and 2.5, respectively. The ECCD test showed an arterial component in 4 cases and a high end-diastolic velocity (EDV) in 14 cases. Four patients (25%), 2 of which had neuropathy, and 2 were in advanced age, did not respond to PGE1 or to oral therapy, 4 patients (25%) (2 treated with insulin and 2 by oral therapy) responded to ICI but not to oral therapy, while 8 patients (50%) showed a good response to both injectable and oral therapy, with good Q3 and Q4 scores.

Conclusions

Good endothelial function appears to be essential for the maintenance of acceptable erectile function. Diabetes has a negative effect on this function, as does hypoxia and low perfusion. Based on the principle that a good erection improves endothelial function, we tried to determine if oral systematic and intracavernous rehabilitation would improve erectile function in diabetic patients. The results indicate that diabetes interferes with erectile function, compromising the effects of the vasoactive drugs. However, integrated systematic rehabilitation appears to allow a good erectile response to both intracavernous and oral therapy in a large number of cases. Therefore, we support this kind of rehabilitative protocol in the treatment of ED in diabetic patients.

Erectile dysfunction: expectations beyond phosphodiesterase type 5 inhibition

In the last few years the pathophysiological mechanisms of erection have been partially clarified, and the molecular machinery of the cellular components of the corpus cavernosum (CC) has been widely investigated. Since erection is a vascular event and the penis is a vascular organ, there must be an intact endothelium for an erection to occur. The regulation of penile tumescence inside the CC involves a balance between contracting and relaxing factors which regulate the functional state of smooth muscle cells. Recent studies have highlighted the importance of new local factors (i.e. phosphodiesterases, rho-kinases and endothelins), and pharmacological agents are available in the armamentarium of the specialist which are targeted to modulate the function of those mediators of erection. It is now well understood that male erectile dysfunction (ED) is a symptom rather than a disease; for this reason in the near future both general practitioners and specialists in internal medicine would have to interplay with sexual medicine. This review is intended to give the clinician some basic concepts of the pathophysiology of erection with relevance to the clinical practice, and to discuss the newest therapeutic approaches for those patients who do not respond to the treatment with oral inhibitors of phosphodiesterase Type 5.

Influence of smoking on predictors of vascular disease

Beyond the already well-established strong causative relationship with cancer, smoking increases the risk for vascular disease. Smoking may act directly or adversely influence risk factors contributing to the development of vascular disease. Smoking causes endothelial dysfunction, dyslipidemia (decreased high-density lipoprotein cholesterol levels, hypertriglyceridemia and increased oxidation of low-density lipoprotein cholesterol) and platelet activation leading to a prothrombotic state. Smoking increases emerging risk factors (eg, fibrinogen, homocysteine, and high-sensitivity C-reactive protein) and increases insulin resistance and the risk of developing type 2 diabetes mellitus. The beneficial effects of statins and antioxidants (eg, vitamins C and E, beta-carotene) are counteracted by smoking. Smoking-induced alterations in growth factors, adhesion molecules, and even in genes can accelerate the progression of atherosclerosis. The aim of this review is to consider the adverse consequences of smoking on the factors predisposing to vascular disease and to emphasize the beneficial effects of smoking cessation.

Cigarette smoking, hypertension and erectile dysfunction

Smoking is associated with an increased risk of developing erectile dysfunction (ED). For example, in the Massachusetts Male Aging Study (MMAS), cigarette smoking amplified the risk of ED associated with other risk factors (e.g. hypertension, diabetes and dyslipidaemia) or with ageing. At the molecular level, several changes associated with smoking have been documented in man and experimental models. These changes could contribute to the pathogenesis of ED. Furthermore, studies performed in dogs demonstrated a smoking-related reduction in arterial flow and venous restriction. Similarly, impaired penile flow has been documented in men who smoke. Cigarette smoking also interferes with the effectiveness of intracavernous papaverine and PGEI. Quitting is the 'first-line' therapy of ED and one of the most important measures for the prevention of atherosclerosis.