Effect of Intracavernosal Injection of Prostaglandin E1 on Duration and Rigidity of Erection in Patients With Vasculogenic Erectile Dysfunction: Is It Dose Dependent?

OBJECTIVE: To assess if the effect of intracavernosal injection of prostaglandin E1 (PGE1) on duration and rigidity of erection is dose dependent in patients with different types of vasculogenic erectile dysfunction (ED)? METHODS: A hundred patients with ED were assigned into 4 groups (n = 25/each); group (A) patients with arteriogenic ED, group (B) patients with veno-occlusive ED, group (C) patients with mixed (arteriogenic and veno-occlusive) ED, and group (D) patients who have only psychogenic ED (control). After intracavernosal injection of PGE1, patients were assessed using penile Doppler ultrasonography and erection hardness score together with calculation of erection duration. The starting dose of PGE1 was 5 µg which was increased to 10 µg and 20 µg as a maximal dose when needed. RESULTS: The mean PSV of patients in groups A, B, C, and D were 24.38 ± 3.3, 37.74 ± 8.28, 22.24 ± 3.85, and 47.76 ± 6.27, respectively. In group D, 88% have achieved the best response at dose of 5 µg while 5.3%, 21.7%, and 0% have achieved the best response at dose of 5 µg in groups A, B, and C, respectively (P < .05 for each). The rest of patients have required either 10 or 20µg to achieve the best response. Patients in group C have required the highest dose of PGE1 to achieve the best response (P < .05). CONCLUSION: Intracavernosal injection of PGE1 in escalating doses have improved the rigidity and duration of erection in patients with different types of vasculogenic ED. Patients with mixed arteriogenic and veno-occlusive ED have required the highest dose of PGE1 to achieve the best response.

Couplet medicines of leech and centipede granules improve erectile dysfunction via inactivation of the CaSR/PLC/PKC signaling in streptozotocin-induced diabetic rats.

Erectile dysfunction (ED) is one of the significant complications of diabetes mellitus (DM), and CASR plays an important role in cellular antiapoptosis and NO production in the vascular endothelium by activating PKC. The present study was aimed to investigate the efficacy of Leech and Centipede Granules (LCG) through the CaSR/PLC/PKC signaling. Fifty male Sprague-Dawley rats were treated with streptozotocin to induce the DM model. After 10 weeks, an apomorphine test was used to confirm DMED. Rats with DMED were administrated with LCG and U73122 for 4 weeks. Fasting blood glucose, body weight, insulin and glucagon levels were measured. Erectile function in rats was assessed by apomorphine. Serums were measured using enzyme-linked immunosorbent assay and flow cytometry, and penile tissues were harvested for histologic and the expression of related targets analyses. After treatment, fasting blood glucose, body weight, insulin, glucagon levels, and erectile function were significantly ameliorated in the LCG groups. The LOX-1, NOX, and EMPs concentrations were significantly decreased with LCG treatment. LCG also continuously increased NO and decreased ET-1 content in penile tissues. LCG and U73122 administration also improved penile fibrosis by significantly decreasing VCAM-1, ICAM-1, and CD62P. The data also showed that LCG reduced the apoptosis level in the penis. Furthermore, the inhibited activation of the CaSR/PLC/PKC pathway was observed in DMED rats with LCG treatment. Collectively, LCG significantly ameliorated erectile function of DMED rats via increased NO generation, inhibiting endothelial cells apoptosis and penile fibrosis, which might benefit from the suppression of CaSR/PLC/PKC pathway in DMED rats.

Folic acid supplementation improves erectile function in patients with idiopathic vasculogenic erectile dysfunction by lowering peripheral and penile homocysteine plasma levels: a case-control study.

BACKGROUND: Erectile dysfunction (ED) has common risk factors with many cardiovascular (CV) impairments. In view of these facts, hyperhomocysteinemia (HHcys) has been postulated for involvement in endothelial dysfunction. OBJECTIVES: We evaluated peripheral and penile homocysteine (Hcys) plasma levels before and after folic acid supplementation in idiopathic vasculogenic erectile dysfunction (ED) patients. MATERIALS AND METHODS: This study included 50 consecutive patients and 50 consecutive healthy controls that were recruited from December 2017 to December 2018. The patients received folic acid (FA) daily for 3 months and were evaluated by the abridged 5-item International Index of Erectile Function (IIEF-5) and penile duplex before and after therapy, in addition to plasma Hcys levels. RESULTS: Our study showed improvement in the severity of ED in our patients as all of them became mild to moderate ED after folic acid administration. Additionally, the median scores of IIEF-5 significantly increased from 6 to 14, respectively (p < 0.001). Furthermore, the median peripheral and penile Hcys plasma levels (µmol/l) significantly decreased after folic acid administration as 39 patients with moderate ED and 11 patients with severe ED were 0.62, 0.34, 5.37, 0.37, respectively, became mild to moderate ED with their median peripheral and penile Hcys plasma levels became 0.19, 0.15, p < 0.001, <0.001, respectively. Peripheral Hcys level correlates significantly with penile Hcys before and after folic acid administration (r: -0.06 p: 0.8, r: 0.9, p < 0.001, respectively). DISCUSSION AND CONCLUSION: Recently, an emerging body of evidence suggests a role for Hcys and folate in erectile function. Interestingly, our interventional study is one of the first that evaluated the effect of folic acid supplementation on HHcys where it demonstrated a significant decrease in peripheral and penile Hcys plasma levels after folic acid administration. Thus, FA should be prescribed concomitantly with phosphodiesterase type 5 inhibitors in ED patients.

Efficacy and safety of combination of tadalafil and aspirin versus tadalafil or aspirin alone in patients with vascular erectile dysfunction: a comparative randomized prospective study.

PURPOSE: We aimed to investigate the efficacy and safety of tadalafil, aspirin, and tadalafil + aspirin combination therapy in vascular erectile dysfunction (VED). METHODS: A total of 336 patients were randomly divided into four groups (group 1, aspirin 100 mg/day, 126 patients; group 2, tadalafil 5 mg/day, 72 patients; group 3, tadalafil 5 mg + aspirin 100 mg, 72 patients; group 4, placebo, 66 patients). In all groups, the changes from baseline to end point in erectile function scores on the International Index of Erectile Function (IIEF-EF) and the number of patients who answered "yes" to questions 2 and 3 of the sexual encounter profile(SEP) were compared statistically. RESULTS: The changes in IIEF-EF scores after treatment were 7.2 ± 4.4, 7.3 ± 4.3, 7.5 ± 4.4, and 2.0 ± 4.6 for group 1 (p < 0.0001), group 2 (p < 0.0001), group 3 (p < 0.0001), and group 4 (p = 0.0204), respectively. The change in SEP-2 ratios after treatment were 36.6%, 36.9%, 41.7%, and 9.4% for group 1 (p < 0.0001), group 2 (p < 0.0001), group 3 (p < 0.0001), and group 4 (p = 0.2925), respectively. The change in SEP-3 ratios after treatment was 46.6%, 49.2%, 53.7%, and 12.5% for group 1 (p < 0.0001), group 2 (p < 0.0001), group 3 (p < 0.0001), and group 4 (p = 0.1456), respectively. In group 2, both the number of patients who reported side effects (p < 0.0001) and stopped using the drug due to side effects (p < 0.05) were significantly higher than the control and others groups. CONCLUSIONS: Successful results were obtained by tadalafil and aspirin monotherapy and tadalafil + aspirin combination therapy in patients with VED. However, the least side effect was observed in the tadalafil + aspirin group. Aspirin can be used alone in the treatment of patients with VED, or combined with tadalafil to reduce side effects and increase success.

Carotid artery intima-media thickness can predict the response of patients with erectile dysfunction to phosphodiesterase 5 inhibitors.

This study investigated the role of carotid artery intima-media thickness (IMT) as a morphological marker of the response of vasculogenic erectile dysfunction (ED) patients to tadalafil, one of the phosphodiesterase 5 inhibitor (PDE5-I). Through March-December 2016, 51 men with vasculogenic ED aged over 30 years were enrolled in this prospective study. Vasculogenic ED was accepted as a normal testosterone level, with penile colour Doppler ultrasonography showing arteriogenic ED, venogenic ED or mixed arteriogenic and venogenic ED. All patients underwent biochemical and hormonal blood tests, ultrasonographic evaluation of the common carotid artery (CCA) IMT and penile colour Doppler ultrasonography. On-demand tadalafil (10 mg or 20 mg in cases of a non-response to 10 mg) was administered to each patient for 2 months. ED was assessed using the short form of International Index of Erectile Function (IIEF-5) before and after the drug therapy. According to the patients' responses to the medication, they were grouped as non-responders or responders. Thirty-one of the 51 patients responded to tadalafil. The mean CCA IMT of the non-responders and responders was 0.9 ± 0.2 mm and 0.6 ± 0.2 mm, respectively (P = 0.000). The IMT of 90% of the non-responders was >0.67 mm, whereas it was >0.67 mm in 40% of the responders. The data were analysed using the Kolmogorov-Smirnov test, Chi-square test, t-test, Mann-Whitney U test and receiver operator characteristic (ROC) curves. Measurement of CCA IMT may offer an alternative and simple method to predict the response of vasculogenic ED patients to PDE5-Is.

Antiplatelet (aspirin) therapy as a new option in the treatment of vasculogenic erectile dysfunction: a prospective randomized double-blind placebo-controlled study.

PURPOSE: To investigate the efficiency of antiplatelet (aspirin) therapy in vasculogenic erectile dysfunction (VED) patients with a high mean platelet volume. METHODS: A total of 184 patients diagnosed with VED between the ages of 18 and 76 were randomly divided into two groups and treated for 6 weeks [group 1: 120 patients (mean age 48.3), aspirin 100 mg/day; group 2: 64 patients (mean age 47.7), placebo 100 mg/day]. The changes from baseline to end point in erectile function scores on the International Index of Erectile Function (IIEF-EF) and the number of patients who answered "yes" to questions 2 and 3 of the sexual encounter profile (SEP) were compared statistically. RESULTS: The mean baseline IIEF-EF scores in groups 1 and 2 were 14.1 ± 4.9 and 14.3 ± 5.2, respectively (p = 0.7966), the number of patients who answered "yes" to SEP-2 was 62 (51.6%) in group 1 and 32 (50%) in group 2 (p = 0.8366), and the number of patients who answered "yes" to SEP-3 was 38 (31.6%) in group 1 and 20 (31.2%) in group 2 (p = 0.9557). In the aspirin group, the changes from baseline to end point in the IIEF-EF, SEP-2, and SEP-3 scores were 7.2, 36.6, and 46.6%, respectively. In the placebo group, these changes were 2.0, 9.4, and 12.5%, respectively. When compared with the placebo group, aspirin-treated subjects showed a significant improvement in all three efficacy measures (p < 0.0001). CONCLUSIONS: 100 mg of aspirin administered once a day significantly improved EF in men with VED.

Unreliability of the Duplex Scan in Diagnosing Corporeal Venous Occlusive Disease in Young Healthy Men With Erectile Deficiency.

OBJECTIVE: To define the role of cavernosal venous occlusive dysfunction (CVOD) as the only cause of erectile dysfunction (ED). MATERIALS AND METHODS: Patients meeting the CVOD criteria without any risk factors for organic ED were randomized into 2 groups; the end-diastolic velocity (EDV), peak systolic velocity (PSV), and resistive index (RI) of their cavernosal arteries were assessed using color duplex Doppler ultrasound (CDDU) after intracavernous injection (ICI) of 10 µg alprostadil. Group 1 (153 patients) underwent repeated CDDU + ICI assessments (a maximum of 3 rounds). Group 2 (149 patients) underwent CDDU + ICI before and after sexological counseling. The percentage data were analyzed using the Cochran-Mantel-Haenszel test; the numerical data were analyzed using the Wilcoxon test. RESULTS: For group 1, the PSVs (median values: first round 42 cm/s; second round 54 cm/s; third round 66 cm/s) and RIs (median values: first round 70%; second round 89%; third round 92%) increased significantly in each CDDU + ICI round, whereas the EDVs were significantly lower (median values: first round 11 cm/s; second round 5 cm/s; third round 1 cm/s). For group 2, the PSVs (median values: from 44 to 67 cm/s) and RIs (from 72% to 93%) increased significantly after sexological counseling, whereas the EDVs (median values: from 12 to 1 cm/s) were significantly lower. CONCLUSION: Repeated CDDU + ICI and counseling strongly diminished the percentage of patients meeting the CVOD criteria, leading to the suspicion that CVOD is linked to psychological issues in highly selected young healthy men with ED.

Herb formula enhances treatment of impotent patients after penile venous stripping: a randomised clinical trials.

Herbs have been regarded as aphrodisiacs in treating impotence for many centuries despite little true scientific evidence. Our latest refined penile venous stripping (PVS) technique is effective in treating impotence, although this procedure remains controversial. A synergic effect of PVS and oral herbs was confirmed in our practice but lacked rigorous scientific proof. The objective of this report was to review our experience with this combination. From August 2010 to May 2014, 263 males underwent PVS. Among these, 67 unsatisfied men chose additional salvage therapy and were randomly assigned to oral herbs (n = 35) or placebo treatment (n = 32) which replaced herb eventually. All were evaluated with the international index of erectile function (IIEF-5) scoring and our dual pharmaco-cavernosography. The pre-op IIEF-5 score for the herb group was 9.7 ± 3.7, post-operative 13.9 ± 3.3 and post-herb 19.6 ± 3.4, while the control group scores were as follows: pre-op 9.3 ± 4.1, post-op 14.5 ± 3.6, post-placebo 15.1 ± 3.5 and post-herb 19.9 ± 3.2. Although there was no significant difference between the two groups pre-operatively, post-operatively and post-herb, a statistically significant difference was found post-salvage therapy (19.6 ± 3.4 versus 15.1 ± 3.6, P < 0.001). It appears that the combination of oral herbs and PVS treatment provides an enhanced outcome to impotent patients refractory to medicine and unsatisfied with PVS monotherapy alone.

Lesion Pattern in Patients With Erectile Dysfunction of Suspected Arterial Origin: An Angiographic Study.

PURPOSE: To determine the specific lesion pattern of supplying arteries in patients with cardiovascular risk factors suffering from treatment-refractory erectile dysfunction (ED). METHODS: From May 2012 to August 2013, 26 men (median age 55 years) poorly responsive to phosphodiesterase-5 inhibitor therapy were evaluated for a possible vascular cause for their ED. The men were examined with penile duplex sonography and digital subtraction angiography (DSA). Arterial lesions in the common and internal iliac arteries and the internal pudendal arteries considered amenable to endovascular therapy were treated with angioplasty ± stents. Retrospectively, 2 blinded investigators independently evaluated the DSA images and categorized the vascular patterns of the erection-related arteries as normal, macroangiopathy (occlusive lesions of the internal pudendal arteries), or microangiopathy (smaller caliber arteries distal to the internal pudendal circulation with no distal arterial reconstitution). RESULTS: Seventeen macroangiopathic lesions were successfully treated by angioplasty in 11 patients. The treated arterial lesions were mainly located in the internal (n=10) and common iliac arteries (n=2), whereas the internal pudendal artery were involved in 5 cases. Microangiopathic lesions lacking distal reconstitution were present in 7 patients, and the remaining 8 patients had normal vessels supplying the penis. Patients with macroangiopathy undergoing angioplasty had a higher prevalence of peripheral artery disease (63.6% vs 6.7%, p=0.003). CONCLUSION: In this preliminary series of ED patients with cardiovascular risk factors and pathologic duplex sonographic flow parameters, roughly 40% exhibited arterial lesions amenable to endovascular revascularization. In the patients with macroangiopathy, vessels upstream of the internal pudendal artery were most commonly affected. More studies are warranted to define the role of endovascular procedures in this ED subpopulation.

Failure to attain stretched penile length after intracavernosal injection of a vasodilator agent is predictive of veno-occlusive dysfunction on penile duplex Doppler ultrasonography.

Penile duplex Doppler ultrasound (PDDU) assesses the etiology of erectile dysfunction. Peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive index (RI) are common PDDU parameters. We assessed whether stretched penile length (SPL) in the flaccid state and measured penile length at peak erection after intracavernosal injection (ICI) of a vasodilator during PDDU correlated with the etiology of erectile dysfunction. We performed a retrospective review of 93 patients who underwent PDDU for erectile dysfunction. Normal and stretched penile length were measured, both at a flaccid state prior to ICI and at peak erection during PDDU. Collected data included patient demographics, vascular, and anatomic parameters. The mean age was 52 years. SPL was equivalent to peak penile length after ICI in 60 patients (65%, group 1) and did not match in 33 (35%, group 2). There were no significant differences between the two groups in terms of flaccid, stretched, and post-ICI erect penile lengths, IIEF score, PSV, percent rigidity or tumescence, and vasodilator dose used. Patients in group 2 had less of a change in penile length from flaccid to erect state (36% vs. 44%, p = 0.02), higher EDV (12.0 vs. 8.5, p = 0.041), lower RI (0.6 vs. 1.0, p = 0.046), and more veno-occlusive dysfunction (82% vs. 53%, p = 0.001). On multivariate analysis, failure to reach maximum SPL at peak ICI erection (OR 2.255, CI 1.191-4.271, p = 0.0126), EDV (OR 1.281, CI 1.115-1.471, p < 0.001) and RI (OR 0.694, CI 0.573-0.723, p = 0.009) predicted veno-occlusive dysfunction. Failure to reach maximal SPL during PDDU using ICI with a vasodilator agent predicted veno-occlusive dysfunction, which is independent of both penile rigidity and tumescence. This measurement could serve as another diagnostic tool for predicting veno-occlusive dysfunction when PDDU is not readily available. Limitations include the subjective nature of penile measurements and different PGE1 doses used.

Pudendal nerve and internal pudendal artery damage may contribute to radiation-induced erectile dysfunction.

PURPOSE/OBJECTIVES: Erectile dysfunction is common after radiation therapy for prostate cancer; yet, the etiopathology of radiation-induced erectile dysfunction (RI-ED) remains poorly understood. A novel animal model was developed to study RI-ED, wherein stereotactic body radiation therapy (SBRT) was used to irradiate the prostate, neurovascular bundles (NVB), and penile bulb (PB) of dogs. The purpose was to describe vascular and neurogenic injuries after the irradiation of only the NVB or the PB, and after irradiation of all 3 sites (prostate, NVB, and PB) with varying doses of radiation. METHODS AND MATERIALS: Dogs were treated with 50, 40, or 30 Gy to the prostate, NVB, and PB, or 50 Gy to either the NVB or the PB, by 5-fraction SBRT. Electrophysiologic studies of the pudendal nerve and bulbospongiosus muscles and ultrasound studies of pelvic perfusion were performed before and after SBRT. The results of these bioassays were correlated with histopathologic changes. RESULTS: SBRT caused slowing of the systolic rise time, which corresponded to decreased arterial patency. Alterations in the response of the internal pudendal artery to vasoactive drugs were observed, wherein SBRT caused a paradoxical response to papaverine, slowing the systolic rise time after 40 and 50 Gy; these changes appeared to have some dose dependency. The neurofilament content of penile nerves was also decreased at high doses and was more profound when the PB was irradiated than when the NVB was irradiated. These findings are coincident with slowing of motor nerve conduction velocities in the pudendal nerve after SBRT. CONCLUSIONS: This is the first report in which prostatic irradiation was shown to cause morphologic arterial damage that was coincident with altered internal pudendal arterial tone, and in which decreased motor function in the pudendal nerve was attributed to axonal degeneration and loss. Further investigation of the role played by damage to these structures in RI-ED is warranted.

Acute effect of sildenafil on inflammatory markers/mediators in patients with vasculogenic erectile dysfunction.

BACKGROUND: Erectile dysfunction (ED) is associated with an incremental inflammatory activation. Evidence suggests that chronic phosphodiesterase 5 (PDE-5) inhibition may have a favorable effect on inflammatory activation and surrogate markers of ED. The aim of this study is to investigate the acute effect of sildenafil on circulating pro-inflammatory markers/mediators in ED patients. METHODS: The study comprised a randomized, double-blind, crossover trial carried out on two separate arms: one with sildenafil 100mg, and one with placebo. Twenty-seven subjects participated in the study (seven in the pilot and 20 in the main phase). In the main phase, blood samples were collected at baseline and at 2 and 4h after sildenafil or placebo administration to determine fibrinogen, high sensitivity C-reactive protein (hsCRP), high sensitivity interleukin-6 (hsIL-6) and tumor necrosis factor α (TNF-α). RESULTS: Administration of sildenafil produced a significant sustained reduction of fibrinogen, hsCRP and hsIL-6 (maximal absolute response of -44mg/dl, 0.42mg/l and 0.68pg/ml at 4h). Likewise, TNF-α was acutely decreased after sildenafil (maximal response of -13pg/ml, 2h). The effect of sildenafil on fibrinogen, hsCRP and hsIL-6 and TNF-α was independent of the baseline values of these markers/mediators or the baseline testosterone level (all P<0.05). Soluble vascular cell adhesion molecule 1 (sVCAM-1) levels remained unchanged. CONCLUSIONS: The present study shows for the first time the acute effect of sildenafil administration on pro-inflammatory markers/mediators in men with vasculogenic ED. This finding may have important implications in ED patients who are considered to be at increased cardiovascular risk.

Endovascular treatment of vasculogenic erectile dysfunction.

The treatment of erectile dysfunction (ED) has been a fascination involving multiple medical specialities over the past century with urologic, cardiac and surgical experts all contributing knowledge toward this multifactorial disease. With the well-described association between ED and cardiovascular disease, angiography has been utilized to identify vasculogenic impotence. Given the success of endovascular drug-eluting stent (DES) placement for the treatment of coronary artery disease, there has been interest in using this same technology for the treatment of vasculogenic ED. For men with inflow stenosis, DES placement to bypass arterial lesions has recently been reported with a high technical success rate. Comparatively, endovascular embolization as an approach to correct veno-occlusive dysfunction has produced astonishing procedural success rates as well. However, after a thorough literature review, arterial intervention is only recommended for younger patients with isolated vascular injuries, typically from previous traumatic experiences. Short-term functional outcomes are less than optimal with long-term results yet to be determined. In conclusion, the hope for a minimally invasive approach to ED persists but additional investigation is required prior to universal endorsement.

[The efficacy of peptide bioregulators of vessels in lower limbs chronic arterial insufficiency treatment in old and elderly people].

Atherosclerosis is a leading cause of obliterating diseases of the arteries in 80-90% of cases. The main pathogenetic mechanism is endothelial dysfunction, leading to hypertension, diabetes, congestive heart failure. The desire of modern society to improve the quality of life increases interest of human health in general and sexual health in particular, because the erectile function is an important factor in the quality of life, which makes us look for more effective methods of diagnosis, treatment and rehabilitation. The objective of the study was to assess the effectiveness of vasoactive tripeptide Vezugen in patients with vasculogenic erectile dysfunction as manifestation of atherosclerosis. Treatment results of erectile dysfunction in 41 patients were studied. A comparative analysis of clinical and instrumental parameters of blood flow in the main penile arteries before and after monotherapy was undertaken. The results show that the blood flow through the main artery of the penis after Vezugen treatment significantly improved both clinical and by objective indicators.

[Sildenafil citrate in the treatment of men with erectile dysfunction].

Based on literature data and the results of own authors' research, the review article considers the efficacy and safety of sildenafil, including its long-term use. Application of this drug leads to an improvement of erectile function in patients of all ages, regardless of etiology, severity and duration of erectile dysfunction (ED). Drug has long-term efficacy. Sildenafil affects both arterial and venous blood flow to the penis, which makes it indicated in vasculogenic erectile dysfunction first. Treatment with sildenafil is accompanied by improvement of the cavernous electrical activity, which justifies its use in neurogenic form of the disease. According to results of IIEF questionnaire, sildenafil provides quick and lasting therapeutic effect. Efficacy and safety of sildenafil is rated as good. As for short-term and long-term use, sildenafil does not cause dependence and addiction.

The use of PDE-5 inhibitors in the treatment of lower urinary tract symptoms due to benign prostatic hyperplasia.

The relationship between lower urinary tract symptoms secondary to BPH and ED has recently been the subject of significant research due to the prevalence of both conditions concomitantly existing in older men. Many large-scale studies have demonstrated an association between erectile dysfunction and lower urinary tract symptoms. Although the mechanisms underlying the relationship between LUTS and ED are not fully elucidated, several theories are currently proposed in literature: the nitric oxide/cGMP pathway, RhoA/Rho-kinase signaling, pelvic atherosclerosis associated with chronic hypoxia, and autonomic adrenergic hyperactivity. The mechanisms by which these pathways affect the bladder, prostate, pelvic vasculature and spinal cord are also the subject of current research. In this chapter, we examine the randomized, placebo-controlled trials that have evaluated the use of PDE-5Is in LUTS, as well as randomized, controlled trials (RCTs) researching combination PDE-5Is and alpha blockers.

Oral L-citrulline supplementation improves erectile function in rats with acute arteriogenic erectile dysfunction.

INTRODUCTION: Oral L-citrulline supplementation increases serum L-arginine levels more efficiently than L-arginine itself and increases nitric oxide (NO) production. AIM: To investigate whether oral L-citrulline supplementation improves erectile function in rats with acute arteriogenic erectile dysfunction (ED). METHODS: We divided 8-week-old male Wistar-ST rats into 3 groups: sham-operated rats (control group), arteriogenic ED rats who underwent ligation of both internal iliac arteries (ligation group), and arteriogenic ED rats receiving oral 2% L-citrulline water supplementation (citrulline group). Citrulline water was given to arteriogenic ED rats for 3 weeks from 1 week after surgery. Erectile function was evaluated by maximum intracavernous pressure/mean arterial pressure (ICP/MAP) ratios via cavernous nerve stimulation at 4 weeks after surgery. Then, the penises were resected, stained with Masson's trichrome, and observed microscopically. Serum nitrogen oxides (NOx) levels were measured by high-performance liquid chromatography. Bonferroni's multiple t-test was used for statistical analysis. MAIN OUTCOME MEASURES: The main outcome measures were changes in ICP/MAP, smooth muscle (SM)/collagen ratios, and NOx levels following L-citrulline supplementation. RESULTS: The ICP/MAP ratio in the ligation group was significantly lower than that in the control group (P<0.05), denoting ED. The ICP/MAP ratio of the citrulline group was significantly higher than that of the ligation group (P<0.05), indicating ED amelioration. Levels of NOx in the ligation group were significantly lower than in the control group (P<0.05), while those in the citrulline group were significantly higher than in the ligation group (P<0.05). SM/collagen ratios in the ligation group were significantly lower than in the control group (P<0.05), while ratios in the citrulline group were significantly higher than those in the ligation group (P<0.05). CONCLUSIONS: Oral L-citrulline supplementation improved ICP/MAP and SM/collagen ratios and increased NOx. Therefore, oral L-citrulline supplementation might be a useful novel therapy for acute arteriogenic ED.

An oral formulation of angiotensin-(1-7) reverses corpus cavernosum damages induced by hypercholesterolemia.

INTRODUCTION: The renin angiotensin system plays a crucial role in erectile function. It has been shown that elevated angiotensin-II levels contribute to the development of erectile dysfunction (ED). Oppositely, angiotensin-(1-7) (Ang-[1-7]) mediates penile erection by activation of receptor Mas. Recently, we have developed a formulation based on Ang-(1-7) inclusion in cyclodextrin (CyD) [Ang-(1-7)-CyD], which allows for the oral administration of Ang-(1-7). AIM: In the present study, we evaluated the effects of chronic treatment with Ang-(1-7)-CyD on penile fibrosis, oxidative stress, and endothelial function in hypercholesterolemic mice. METHODS: Apolipoprotein(Apo)E-/- mice fed a Western-type diet for 11 weeks received Ang-(1-7)-CyD or vehicle during the final 3 weeks. Collagen content and reactive oxygen species (ROS) production within the corpus cavernosum were evaluated by Sirius red and dihydroethidium staining, respectively. Protein expression of neuronal nitric oxide synthase (nNOS) and endothelial nitric oxide synthase (eNOS), nicotinamide adenine dinucleotide phosphate (NADPH) subunits (p67-phox and p22-phox), and AT1 and Mas receptors in the penis was assessed by Western blotting. Nitric oxide (NO) production was measured by Griess assay in the mice serum. Cavernosal strips were mounted in an isometric organ bath to evaluate the endothelial function. MAIN OUTCOME MEASURES: The effect of Ang-(1-7)-CyD treatment on penile fibrosis, oxidative stress, and endothelial function in hypercholesterolemia-induced ED. RESULTS: Ang-(1-7)-CyD treatment reduced collagen content in the corpus cavernosum of ApoE-/- mice. This effect was associated with an attenuation of ROS production and a diminished expression of NADPH. Furthermore, Ang-(1-7)-CyD treatment augmented the expression of nNOS and eNOS in the penis and elevated vascular NO production. Importantly, these effects were accompanied by an improvement in cavernosal endothelial function. CONCLUSION: Long-term treatment with Ang-(1-7)-CyD reduces penile fibrosis associated with attenuation of oxidative stress. Additionally, cavernosal endothelial function in hypercholesterolemic mice was markedly improved. These results suggest that Ang-(1-7)-CyD might have significant therapeutic benefits for the treatment of erectile dysfunction.