Efficacy of tadalafil on improvement of men with erectile dysfunction caused by COVID-19:A randomized placebo-controlled trial

Objective: According to the high prevalence of COVID-19 and the subsequent risk of men's sexual health, we decided to investigate the efficacy of tadalafil on improvement of men with erectile dysfunction caused by COVID-19.Methods: In this study, 70 outpatients who were recovered from COVID-19 without acute respiratory distress syndrome with negative polymerase chain reaction test and a complaint of erectile dysfunction were divided into two groups: 35 patients who received tadalafil 5 mg daily and 35 who received placebo. For each patient, basic assessment of sexual function was performed using the 5-item version of the International Index of Erectile Function (IIEF-5) questionnaire. Then, treatment was started from 2 months after complete recovery of COVID-19 with negative polymerase chain reaction test for 3 months. At the end of the treatments, the patients were re-evaluated for sexual function using the complete version of IIEF questionnaire. Finally, the results before and after treatment in the intervention group were compared with those of the control group.Results: Treatment with both tadalafil and placebo improved the patients' sexual function criteria compared to the baseline. However, this improvement was significantly higher in the intervention group with tadalafil than the control group with placebo (p<0.05).Conclusion: Daily administration of tadalafil 5 mg seems to be effective and safe for improvement of erectile dysfunction caused by COVID-19.

Mesenchymal stem cell secretome: A promising therapeutic strategy for erectile dysfunction?

Objective:The secretome,comprising bioactive chemicals released by mesenchymal stem cells(MSCs),holds therapeutic promise in regenerative medicine.This review aimed to explore the therapeutic potential of the MSC secretome in regenerative urology,particularly for treating erectile dysfunction(ED),and to provide an overview of preclinical and clinical research on MSCs in ED treatment and subsequently to highlight the rationales,mechanisms,preclinical investigations,and therapeutic potential of the MSC secretome in this context.Methods:The review incorporated an analysis of preclinical and clinical research involving MSCs in the treatment of ED.Subsequently,it delved into the existing knowledge regarding the MSC secretome,exploring its therapeutic potential.The methods included a comprehensive examination of relevant literature to discern the processes underlying the therapeutic efficacy of the MSC secretome.

Dual innervation method to preserve erectile function following prostatectomy

Prostate cancer is the second most prevalent cancer in men.Robot-assisted radical prostatectomy(RARP)has altered the landscape of prostate cancer treatment.Despite the excellent oncological outcomes associated with RARP,the rate of erectile dysfunction(ED)remains high.Primary repair of disrupted cavernous nerves with interpositional nerve grafts has been described;however,the outcomes have been inconsistent.We hypothesize that this is attributed to Schwann cell atrophy and axonal regeneration limitations caused by long nerve grafts.We proposed the use of nerve transfer to support axonal regrowth via an inter-positional graft with additional donor axons.A cadaveric study was performed to evaluate the anatomical feasibility of a vastus lateralis nerve(VLN)transfer to the distal recipient cavernous nerve stump.The VLN is long with multiple branching patterns that allow tension-free coaptation of the cavernous nerve.We postulate that a dual innervation method using VLN nerve transfer together with interpositional nerve graft repair of the transacted cavernous nerves may improve the outcomes of ED post-RARP.

Enhancing Erectile Function and Alleviating Andropause Symptoms: Clinical Efficacy of a Human Stem Cell Conditioned Medium Cream

Erectile dysfunction (ED) is increasingly prevalent in Japan, exceeding 30%, and increasing with age. Unhealthy lifestyle habits, obesity, insufficient exercise, and smoking have been implicated in its pathogenesis, along with endothelial dysfunction of the corpora cavernosa and impaired blood flow to the penis considered underlying factors. However, the current treatments are limited to Phosphodiesterase-5 (PDE5) inhibitors. ED is the primary symptom of andropathy. This study reports the clinical efficacy of human stem cell-conditioned medium cream for ED treatment. Ten men without underlying diseases suspected of andropause with ED (mean age 43.2 ± 4.4 y, Hb 15.2 ± 0.6 gm/dL, AST/ALT 30.2/37.9 ± 12.4/14.0, eGFR 82.7 ± 12.4 mL/min/1.73 m2) were targeted. The cream was applied twice daily to the genital and scrotal areas. The erectile hardness score (EHS), International Index of Erectile Function-5 (IIEF-5), and Aging Male Symptoms (AMS) scale were used to evaluate the participants before and 30 days after use, and the results were compared using paired t-tests. The post-use qualitative opinions were collected through interviews. Significant improvements were observed compared to baseline in the IIEF-5 (11.8 ± 4.6→17.2 ± 5.1, P < 0.001), and AMS (46.3 ± 6.7→37.6 ± 5.3, P < 0.001) scores post cream use. EHS did not show a statistically significant difference, but a trend towards improvement was observed. Qualitative feedback included increased morning erection, improved maintenance of erection during intercourse, and reduced post work fatigue. Human stem cell-conditioned medium contains endothelial growth factors that potentially contribute to the improvement of ED and andropause by enhancing corporal endothelial function. Future studies should include control groups to further investigate the efficacy of these treatments.

The mechanistic study on Wa medicine Niang-Mu-Liang medicinal liquor mitigating diabetes mellitus erectile dysfunction in rats by inhibiting ferroptosis

Background:This study aims to investigate the therapeutic effect of Wa medicine Niang-Mu-Liang medicinal liquor(NML)on rats with diabetes mellitus erectile dysfunction(DMED)and its impact on the ferroptosis signaling pathway.Methods:Thirty Sprague-Dawley rats were randomly divided into three groups:Control,DMED,and NML.After establishing the DMED model,treatments were administered for 8 weeks.After the administration,apomorphine hydrochloride tests were conducted to measure the mass and organ index of testes and epididymides,sperm concentration and viability in each group.Penile corpus cavernosum tissues were stained with hematoxylin and eosin.Nitric oxide and cyclic guanosine monophosphate levels in the penile corpus cavernosum tissues were determined using biochemical kits and enzyme-linked immunosorbent assay,while the expression of proteins related to the ferroptosis signaling pathway was measured by Western blot.Results:Compared to the DMED group,the DMED rats treated with NML showed significantly increased erection frequency,testicular and epididymal mass and index,sperm count and viability,along with noticeable improvement in the pathological morphology of penile corpus cavernosum.The content of nitric oxide and cyclic guanosine monophosphate,and the expression of ferritin heavy chain,ferritin light chain,and glutathione peroxidase 4 proteins in penile corpus cavernosum tissue were elevated,while the expression of transferrin and STEAP3 proteins was reduced.Conclusion:NML can improve erectile function in DMED rats by inhibiting the ferroptosis signaling pathway.

Pathogenesis and treatment of diabetes mellitus-related erectile dysfunction: current therapies and potential challenges

Erectile dysfunction(ED)is one of the important complications of diabetes,which is very common in diabetic patients,affecting more than half of male patients,and the incidence of the disease is about 3.5 times that of the normal population.The pathogenesis of diabetic erectile dysfunction(DMED)is complex,involving nerve,vascular,endocrine,muscular and psychological aspects.At present,the therapeutic approaches of DMED include drug therapy,surgery,physical therapy and so on.This article provides a review of current research on the pathogenesis and treatment of DMED.Further elucidation of the pathogenesis of DMED and the development of new therapeutic approaches are of great significance for the prevention and treatment of DMED.

Combination therapy for erectile dysfunction： an update review

The introduction of oral phosphodiesterase-5 inhibitors （PDE51s） in the late 1990s and early 2000s revolutionized the field of sexual medicine and PDE51s are currently first-line monotherapy for erectile dysfunction （ED）. However, a significant proportion of patients with complex ED will be therapeutic non-responders to PDE51 monotherapy. Combination therapy has recently been adopted for more refractory cases of ED, but a critical evaluation of current combination therapies is lacking. A thorough PubMed and Cochrane Library search was conducted focusing on the effectiveness of combination therapies for ED in therapeutic non-responders to PDE51 therapy. Journal articles spanning the time period between January 1990 and December 2010 were reviewed. Criteria included all pertinent review articles, randomized controlled trials, cohort studies and retrospective analyses. References from retrieved articles were also manually scanned for additional relevant publications. Published combination therapies include PDE51 plus vacuum erectile device （VED）, intraurethral medication, intracavernosal injection （ICI）, androgen supplement, a-blocker or miscellaneous combinations. Based on this review, some of these combination treatments appeared to be quite effective in preliminary testing. Caution must be advised, however, as the majority of combination therapy articles in the last decade have numerous limitations including study biases and small subject size. Regardless of limitations, present combination therapy research provides a solid foundation for future studies in complex ED management.

Stem cell therapy and diabetic erectile dysfunction:A critical review

Erectile dysfunction(ED)has been identified as one of the most frequent chronic complications of diabetes mellitus(DM).The prevalence of ED is estimated to be about 67.4%in all DM cases worldwide.The pathophysiological process leading to ED involves endothelial,neurological,hormonal,and psychological factors.In DM,endothelial and neurological factors play a crucial role.Damages in the blood vessels and erectile tissue due to insulin resistance are the hallmark of ED in DM.The current treatments for ED include phosphodiesterase-5 inhibitors and penile prosthesis surgery.However,these treatments are limited in terms of just relieving the symptoms,but not resolving the cause of the problem.The use of stem cells for treating ED is currently being studied mostly in experimental animals.The stem cells used are derived from adipose tissue,bone,or human urine.Most of the studies observed an improvement in erectile quality in the experimental animals as well as an improvement in erectile tissue.However,research on stem cell therapy for ED in humans remains to be limited.Nevertheless,significant findings from studies using animal models indicate a potential use of stem cells in the treatment of ED.

Molecular Yin and Yang of erectile function and dysfunction

In regard to erectile function, Yin is flaccidity and Yang erection. In the past decade, research has mostly focused on the Yang aspect of erectile function. However, in recent years, the Yin side is attracting increasingly greater attention. This is due to the realization that penile flaccidity is no less important than penile erection and is actively maintained by mechanisms that play critical roles in certain types of erectile dysfunction （ED）; for example, in diabetic patients. In addition, there is evidence that the Yin and Yang signaling pathways interact with each other during the transition from flaccidity to erection, and vice versa. As such, it is important that we view erectile function from not only the Yang but also the Yin side. The purpose of this article is to review recent advances in the understanding of the molecular mechanisms that regulate the Yin and Yang of the penis. Emphasis is given to the Rho kinase signaling pathway that regulates the Yin, and to the cyclic nucleotide signaling pathway that regulates the Yang. Discussion is organized in such a way so as to follow the signaling cascade, that is, beginning with the extracellular signaling molecules （e.g., norepinephrin and nitric oxide） and their receptors, converging onto the intracellular effectors （e.g., Rho kinase and protein kinase G）, branching into secondary effectors, and finishing with contractile molecules and phosphodiesterases. Interactions between the Yin and Yang signaling pathways are discussed as well.

Medical management of erectile dysfunction in aging males： is it too late to treat？

Erectile dysfunction （ED） is a common disorder among aging males. However, most aging males refuse to seek medical help and believe that ED is an irreversible event in the aging process. The purpose of this study was to describe the current medical management of ED in aging males and to examine whether it is too late to treat this disorder in these elderly men. From 2007 to 2008, 4507 patients diagnosed with ED were gathered from 46 centers in China; 4241 completed the study, 3837 of whom were treated with sildenafil. The 3837 patients were divided into five groups based on age （group A： 20-30 years; group B： 31-40 years; group C： 41-50 years; group D： 51-60 years; and group E： 〉60 years）. After comparing pre- and posttreatment International Index of Erectile Function-Erectile Function domain （IIEF-EF） questionnaires, Erection Hardness Scale （EHS）, and IIEF Q13 （＂How satisfied have you been with your overall sex life？＂）, we discovered that the aging males had worse erectile function, erection hardness, and sexual satisfaction than the younger males （P〈 0.001）. After treatment, the improvement rates in the IIEF-EF, EHS, and IIEF Q13 scores were 107.0%, 83.1%, and 116.5%, respectively. The magnitude of these changes demonstrated significant differences among groups （P 〈 0.001）. Accordingly, aging males are likely to benefit more from medical treatment. We propose that aging males should be informed that age is not a limiting factor for medical ED management, and it is never too late to treat.

Pathophysiology and treatment of diabetic erectile dysfunction

The pathophysiology of diabetes is multifactorial and no single etiology is at the forefront. The proposed mechanisms of erectile dysfunction （ED） in diabetic patients includes elevated advanced glycation end-products （AGEs） and increased levels of oxygen free radicals, impaired nitric oxide （NO） synthesis, increased endothelin B receptor binding sites and ultrastructural changes, upregulated RhoA/Rho-kinase pathway, NO-dependent selective nitrergic nerve degeneration and impaired cyclic guanosine monophosphate （cGMP）-dependent kinase-1 （PKG-1）. The treatment of diabetic ED is multimodal. Treatment of the underlying hyperglycemia and comorbidities is of utmost importance to prevent or halt the progression of the disease. The peripherally acting oral phosphodiesterase type 5 （PDE5） inhibitors are the mainstay of oral medical treatment of ED in diabetics. Vacuum erection devices are an additional treatment as a non-invasive treatment option. Local administration of vasoactive medication via urethral suppository or intracorpora! injection can be effective with minimal side-effects. Patients with irreversible damage of the erectile mechanism are candidates for penile implantation. Future strategies in the evolution of the treatment of ED are aimed at correcting or treating the underlying mechanisms of ED. With an appropriate vector, researchers have been able to transfect diabetic animals with agents such as neurotrophic factors and nitric oxide synthase （NOS）. Further studies in gene therapy are needed to fully ascertain its safety and utility in humans.

Prevalence and risk factors of erectile dysfunction in three cities of China: a community-based study

Aim: To determine the age-adjusted prevalence of erectile dysfunction (ED) in 3 big cities of China and to explore its potential sociodemographic, medical and lifestyle correlates. Methods: A cross-sectional, population-based survey was conducted in three cities of China. Structured questionnaires were administered to 2 226 men, aged 20 - 86 years, by trained interviewers. Results: The age-adjusted prevalence of ED was 28.34 % (mild 15.99 %, moderate 7.14 %, severe 5.21 %). In the men above 40, the prevalence was 40.2%. Age was positively correlated with ED (P<0.01). Education was negatively correlated with ED (P<0.01). Spouse companionship, living condition were positively correlated with ED (P<0.01). Histories of cardiovascular disease, diabetes, and hyperlipidemia were positively correlated with ED (P<0.01). Cigarette smoking was not correlated with ED (P>0.05), while the cigarette consumption and duration were positively correlated with ED (P<0.01). Alcohol drinking is negatively correlated with ED (P<0.01). The duration of drinking was positively correlated with ED (P<0.01). Weekly alcohol consumption was not correlated with ED (P>0.05). Conclusion: The prevalence of ED increased with age. Cardiovascular disease, diabetes and hyperlipidemia were positively correlated with the increased prevalence. Sociodemographic and lifestyle factors, such as education, spouse companionship, living condition, cigarette and alcohol consumption or duration also have association with the prevalence of ED.

Effects of icariin on erectile function and expression of nitric oxide synthase isoforms in castrated rats

Aim： To investigate the effect of icariin on erectile function and the expression of nitric oxide synthase （NOS） isoforms in castrated rats. Methods： Thirty-two adult male Wistar rats were randomly divided into one shamoperated group （A） and three castrated groups （B, C and D）. One week after surgery, rats were treated with normal saline （groups A and B） or oral icariin （1 mg/[kg·day] for group C and 5 mg/[kg·day] for group D） for 4 weeks. One week after treatment, the erectile function of the rats was assessed by measuring intracavernosal pressure （ICP） during electrostimulation of the cavernosal nerve. The serum testosterone （ST） levels, the percent of smooth muscle （PSM） in trabecular tissue, and the expression of mRNA and proteins of neuronal nitric oxide synthase （nNOS）, inducible nitric oxide synthase （iNOS）, endothelial nitric oxide synthase （eNOS） and phosphodiesterase V （PDES） in corpus cavernosum （CC） were also evaluated. Results： ICP, PSM, ST and the expression of nNOS, iNOS, eNOS and PDE5 were significantly decreased in group B compared with those in group A （P 〈 0.01）. However, ICE PSM and the expression of nNOS and iNOS were increased in groups C and D compared with those in group B （P 〈 0.05）. Changes in ST and the expression of eNOS and PDE5 were not significant （P 〉 0.05） in groups C and D compared with those in group B. Conclusion： Oral treatment with icariin （〉 98.6 % purity） for 4 weeks potentially improves erectile function. This effect is correlated with an increase in PSM and the expression of certain NOS in the CC of castrated rats. These results suggest that icariin may have a therapeutic effect on erectile dysfunction.

Improvement in erectile dysfunction after insulin-like growth factor-1 gene therapy in diabetic rats

Aim： To determine whether adenoviral gene transfer of insulin like growth factor-1 （IGF-1） to the penis of streptozotocin （STZ）-induced diabetic rats could improve erectile capacity. Methods： The STZ diabetic rats were transfected with AdCMV-βgal or AdCMV-IGF-1. These rats underwent cavernous nerve stimulation to assess erectile function and their responses were compared with those of age-matched control rats 1 to 2 days after transfection. In control and transfected STZ diabetic rats, IGF-1 expression were examined by reverse transcription polymerase chain reaction （RT-PCR）, Western blot and histology. The penis β-galactosidase activity and localization of the STZ diabetic rats were also determined. Results： One to two days after transfection, the β-galactosidase was found in the smooth muscle cells of the diabetic rat penis transfected with AdCMV-βgal. One to 2 days after administration of AdCMV- IGF-1, the cavernosal pressure, as determined by the ratio of maximal intracavernous pressure-to-mean arterial pressure （ICP/MAP） and total intracavernous pressure （ICP）, was increased in response to cavernous nerve stimulation. Transgene expression was confirmed by RT-PCR, Western blot and histology. Conclusion： Gene transfer of IGF-1 significantly increased erectile function in the STZ diabetic rats. These results suggest that in vivo gene transfer of IGF- 1 might be a new therapeutic intervention for the treatment of erectile dysfunction （ED） in the STZ diabetic rats.

Transplantation of endothelial progenitor cells transfected with VEGF165 to restore erectile function in diabetic rats

The present study investigated the effect of transplanting endothelial progenitor cells （EPCs） transfected with the vascular endothelial growth factor gene （VEGF165） into the corpora cavernosa of rats with diabetic erectile dysfunction （ED）. A rat model of diabetic ED was constructed via intraperitoneal injection of streptozotocin. After streptozotocin treatment, pre-treated EPCs from each of three groups of rats were transplanted into their corpora cavernosa. Our results, following intracavernosal pressure （ICP） monitoring, showed that ICP increased significantly among rats in the trial group when compared to the results from rats in the blank-plasmid and control groups during basal conditions and electrical stimulation （P〈O.01 for both comparisons）. Histological examination revealed extensive neovascularisation in the corpora cavernosa of rats in the trial group. Fluorescence microscopy indicated that many of the transplanted EPCs in the trial group survived, differentiated into endothelial cells and integrated into the sites of neovascularisation. Based on the results of this study, we conclude that transplantation of VEGF165-transfected EPCs into the corpora cavernosa of rats with diabetic ED restores erectile function.

Resveratrol, an activator of SIRT1, restores erectile function in streptozotocin-induced diabetic rats

The high incidence of erectile dysfunction （ED） in diabetes highlights a need for effective treatment strategies. Resveratrol, an activator of silent information regulator 2-related enzymes 1 （sirtuinl, SIRT1）, has received attention for its valuable effects in cancer, neurodegenerative diseases, longevity and cardiovascular disease. To explore the effects of resveratrol in diabetes-induced ED, resveratrol was administered to rats with streptozocin （65 mg kg-1）-induced diabetes. Erectile function, cavernous structure, tissue protein expression of silent information regulator 2-related enzymes 1 （sirtuinl, SIRT1）, p53 and forkhead transcription factor 0 3a （FOXO3a）, superoxide dismutase （SOD） activity and malondialdehyde （MDA） levels in the corpora cavernosa were studied. We found that SIRT1 was expressed in cavernosal tissue, and it was downregulated in the corpora of diabetic rats. The administration of resveratrol upregulated the expression of SI RT1 and restored erectile function. In contrast, resveratrol downregulated the expression of p53 and FOXO3a, which regulate apoptosis and oxidative stress. Furthermore, the resveratrol-treated group showed an improvement in smooth muscle content, SOD activity and MDA levels when compared with the diabetic group. Therefore, the ability of resveratrol to improve diabetes-induced ED is likely related to its activation of SIRT1 expression, thus causing the suppression of apoptosis and resistance towards oxidative stress.

Effect of icarisid II on diabetic rats with erectile dysfunction and its potential mechanism via assessment of AGEs, autophagy, roTOR and the NO-cGMP pathway

Erectile dysfunction （ED） is a major complication of diabetes mellitus. Icariin has been shown to enhance erectile function through its bioactive form, icarisid Ih This study investigates the effects of icarisid Ⅱ on diabetic rats with ED and its potential mechanism viathe assessment of advanced glycosylation end products （AGEs）, autophagy, mTOR and the NO-cGMP pathway. Icarisid Ⅱ was extracted from icariin by an enzymatic method. In the control and diabetic ED groups, rats were administered normal saline; in the icarisid Ⅱ group, rats were administered icarisid Ⅱ intragastrically. Erectile function was evaluated by measuring intracavernosal pressure/mean arterial pressure （ICP/MAP）. AGE concentrations, nitric oxide synthase （NOS） activity and cGMP concentration were assessed by enzyme immunoassay. Cell proliferation was analysed using methyl thiazolyl tetrazolium assay and flow cytometry. Autophagosomes were observed by transmission electron microscopy, monodansylcadaverine staining and GFP-LC3 Iocalisation. The expression of NOS isoforms and key proteins in autophagy were examined by western blot. Our results have shown that Icarisid Ⅱ increased ICP/MAP values, the smooth muscle cell （SMC） growth curve, S phase and SMC/collagen fibril （SMC/CF） proportions and decreased Beclin 1 （P〈0.05）. Icarisid Ⅱ significantly increased the proliferative index and p-p70S6K（Thr389） levels and decreased the numbers of autophagosomes and the levels of LC3-11 （P〈0.01）. Icarisid Ⅱ decreased AGE concentrations and increased cGMP concentration, NOS activity （P〈0.05） and cNOS levels （P〈0.01） in the diabetic ED group. Therefore, Icarisid Ⅱ constitutes a promising compound for diabetic ED and might be involved in the upregulation of SMC proliferation and the NO-cGMP pathway and the downregulation of AGEs, autophagy and the mTOR pathway.

Effect of tankyrase 1 on autophagy in the corpus cavernosum smooth muscle cells from ageing rats with erectile dysfunction and its potential mechanism

This study compared tankyrase 1 expression and autophagy quantity between erectile dysfunction （ED） and non-ED rats＇ corpus cavernosum smooth muscle cells （CSMCs）. This study aslo explored the effect and possible mechanism of tankyrase 1 on autophagy and cell proliferation in ageing ED rats＇ CSMCs. The intracavernous pres- sure and mean systemic arterial pressure were measured to investigate erectile function so that eight 24-month-old ED and eight 8-month-old male Wistar rats were choosed respectively. The rat CSMCs were isolated and cultured by enzyme digestion, in which tankyrase 1 expression and autophagy quantity were compared. Tankyrase 1 over-expression was induced with plasmid transfection by Lipofectamine^TM. The effect of tankyrase 1 overexpression on proliferation, autophagy and mTOR pathway in 24-month-old ED rats＇ CSMCs was measured by the cell growth curve in MTT assay, cell cycle analysis in flow cytometry （FCM）, key protein expression in Western blot, autophagy quantity in transmission electron microscopy, monodansylcadaverine staining and GFP-LC3 fluorescence. The primary CSMCs were confirmed by immunofluorescence, and the purity was 99.1% in FCM. Compared with that of 8-month-old rats, tankyrase 1 expression and autophagy quantity significantly decreased in 24-month-old ED rats＇ primary CSMCs （P 〈 0.01）. Tankyrase 1 overexpression significantly increased the growth rate （P 〈 0.05） and increased the S phase of cell cycle （P 〈 0.01）. The autophagosome quantity was remarkably increased （P 〈 0.01）, LC3-Ⅰ/Ⅱ and Beclin 1 were upregulated （P 〈 0.01 and P 〈 0.05）, and p-p70S6K （Thr389） was downregulated in 24-month-old ED rat CSMCs （P 〈 0.05）. In conclusion, Tankyrase 1 and autophagy decrease in the CSMCs from aging rats with ED, and tankyrase 1 may have a positive effect on proliferation by enhancing autophagy and regulating the mTOR signalling pathway.

Improved spontaneous erectile function in men with mild-tomoderate arteriogenic erectile dysfunction treated with a nightly dose of sildenafil for one year： a randomized trial

Aim： To test the hypothesis that sildenafil （50 mg nightly for one year） can improve spontaneous erectile function （EF） in men with mild-to-moderate arteriogenic erectile dysfunction （ED） responsive to erectogenic treatment. Methods： In a prospective open-label trial, 112 men with ED were randomized to sildenafil 50 mg nightly or sildenafil 50 or 100 mg as needed for 12 months, followed by one-month and 6-month non-medicated periods. Non-randomized, non-medicated men with ED were also assessed. The EF domain of the International Index of Erectile Function （IIEF EF） and the peak systolic velocity （PSV） of penile cavernous arteries were used to measure the efficacy. Results： After sildenafil treatment and a subsequent non-medicated month, IIEF EF was normal in 29 of 48 （60.4%, 95% confidence interval [CI]： 45.3-74.2%） of the nightly group vs. 4 of 49 （8.2%, 95% CI： 2.3-19.6%） of the as-needed group. PSV improved by 11.2 cm/s （95% CI： 4.7-21.4; P = 0.012） in the nightly group but only by 3.4 cm/s （-5.1- 14.7; P = 0.435） in the as-needed group. IIEF EF normalized in 1 of 18 （5.6%, 95% CI： 0.1-27.3%） non-medicated men and the PSV declined slightly. Six months after treatment, the IIEF EF remained normal and PSV was stabilized in most （28/29, 97%） nightly group men who had initially normalized. Conclusion： Sildenafil nightly for one year resulted in ED regression that persisted well beyond the end of treatment, so that spontaneous EF was characterized as normal on the IIEF in most men. The results from this open-label, randomized trial warrant verification under double-blind, placebo-controlled conditions.

Prevalence and medical management of erectile ：lysfunction in Asia

Erectile dysfunction （ED） is an important worldwide health issue that has a significant negative impact on the quality of life and life satisfaction of both the affected individual and his partner. Here we review the prevalence of ED in Asia, associated factors that may influence sexual attitudes and sexual behaviours, and randomized clinical trials （RCTs） of phosphodiesterase-5 （PDE-5） inhibitors to evaluate the clinical efficacy and safety of PDE-5 inhibitors in Asian men. We searched for English-language articles in MEDLINE and PubMed from January 2000 to September 2010. Our results showed that the overall reported prevalence rate of ED in Asia ranged widely, from 2% to 88%. This finding indicates that ED is a common and major health problem in this region. However, sociocultural and economic factors in Asia prevent people from seeking and obtaining appropriate medical care. We found reports on five kinds of PDE-5 inhibitors for the management of ED.＇ sildenafil, vardenafil, tadalafil, udenafil and mirodenafih The results of RCTs showed that these five PDE-5 inhibitors are more effective than placebo in improving erectile function in Asian men with ED and that these drugs have similar efficacy and safety profiles.