Neuroprotective and Nerve Regenerative Approaches for Treatment of Erectile Dysfunction after Cavernous Nerve Injury

New valproate regulations, informed choice and seizure risk

Valproate is the most effective medication for generalised epilepsies, and several specific epilepsy syndromes. For some people, it will be the only medication to establish seizure remission, and withdrawing it carries risks of seizure recurrence and Sudden Unexpected Death in Epilepsy (SUDEP). It is also of proven efficacy for bipolar disorder and migraine prevention. Guidelines based on observational and epidemiological studies stress that maternal valproate related teratogenicity and neurodevelopmental effects are significantly higher than for other antiseizure medications (ASMs). It should, therefore, only be used if other medications are ineffective and after balancing the teratogenicity risk. Regulatory restrictions have changed prescribing practices and reduced valproate use. The number of other medications that must be trialled in the different conditions for which valproate has effectiveness and the consequences of the lack of efficacy of those drugs leading to significant harm including death remains unexplored. Risk minimisation measures (RMMs) for valproate, chiefly Pregnancy Prevention practices (PPP), consider foetal risk and not risk to people living with epilepsy. In the United Kingdom (UK), limitations relating to valproate use in all people < 55 years commenced in January 2024. While the evidence in child-bearing women is not disputed, the data in males are based on animal models, case reports, and one commissioned, unpublished, non-peer reviewed report unavailable to the UK public, stakeholder charities or professionals. Evidence suggests that 30-40% of people switching from valproate have breakthrough seizures. Thus, an estimated 21,000-28000 people in the UK will imminently be exposed to the potential hazards of breakthrough seizures, including death. There is little government investment in monitoring the effects of these changes to valproate prescribing on patient health and quality of life. This review summarises the history of valproate regulation, evidence underpinning it and argues how the latest regulations in the UK do not align with the country's medical regulatory bodies ethical principles nor with the Montgomery principles of informed patient choice and autonomy. It dissects how such regulations infringe Common Law principles, nor give due regard for patient outcomes beyond reproduction. The paper looks to provide recommendations to redress these concerns while appreciating the core need for such governance to emerge in the first place.

Emergent Penile Venous Stripping for Treating Adolescent Impotence

INTRODUCTION

Traditional anatomy-based penile venous surgery is deemed inadequate. Based on revolutionary insights into penile vasculature, penile venous stripping (PVS) shows promise in treating adolescent erectile dysfunction (AED). We aimed to report on this novel approach.

METHODS

We conducted a retrospective analysis of 223 individuals under 30 diagnosed with veno-occlusive dysfunction (VOD) between 2009 and 2023. Among them, 83 were diagnosed with AED and divided into the PVS (n = 37) and no-surgery (NS, n = 46) groups. All participants had been dissatisfied with conventional therapeutic options. Dual pharmaco-cavernosography was the primary diagnostic modality. PVS involved stripping the deep dorsal vein and two cavernosal veins after securing each emissary's vein with a 6-0 nylon suture. Erection restoration was accessed using the abridged five-item version of the International Index of Erectile Function (IIEF-5) score system and the erection hardness scale (EHS). Statistical analysis was performed using IBM SPSS 21.0.

RESULTS

There were significant differences (both p < 0.001) between the preoperative and postoperative IIEF-5 scores in the PVS and NS groups (9.8 ± 3.0 vs. 20.4 ± 2.2; 9.9 ± 2.5 vs. 9.5 ± 2.1), as well as in the EHS scores (1.7 ± 0.7 vs. 3.5 ± 0.6 and 1.8 ± 0.5 vs. 1.3 ± 0.4). The satisfaction rate was 87.9% (29/33) in the PVS group and 16.7% (17/41) in the NS group.

CONCLUSIONS

AED can be effectively treated using physiological methods, although larger patient cohorts are needed for validation.

Riluzole, a neuroprotective agent, preserves erectile function following bilateral cavernous nerve injury in male rats

Neurogenic erectile dysfunction is a highly prevalent complication in men undergoing radical prostatectomy. The underlying mechanisms remain incompletely defined and the effective therapy has been limited. This study aimed to evaluate the protective effect of riluzole and the role of PKC β and excitatory amino acid transporters (EAATs) mediating this effect in a rat model of bilateral cavernous injury (BCNI). A total of 48 male Sprague-Dawley rats were divided into sham, BCNI (at 7, 15 days post-injury) and BCNI treated with riluzole (8 mg/kg/day) groups. Erectile function was measured as maximum intracavernosal pressure (mICP)/mean arterial pressure (MAP) and total ICP/MAP. Changes in protein expressions of phospho (p)-PKC β IIser660 and EAATs were analysed in penis and major pelvic ganglion with western blotting. BCNI decreased erectile function at 7 and 15 days post-injury (mICP/MAP at 4 V: 0.45 ± 0.06 vs 0.84 ± 0.07; 0.34 ± 0.04 vs 0.77 ± 0.04 respectively; p < 0.001) whereas riluzole treatment (for 15 days) preserved erectile function (mICP/MAP at 4 V: 0.62 ± 0.03 vs 0.34 ± 0.04; p < 0.01). The decline in the expression of p-PKC β IIser660 was observed in penis at 7 and 15 days post-injury (p = 0.0003, p = 0.0033), which was prevented by riluzole treatment for 15 days (p = 0.0464). While expressions of EAAT-1 and EAAT-2 decreased in major pelvic ganglion following BCNI (p = 0.0428, p = 0.002), riluzole treatment for 15 days prevented the decrease only in EAAT-2 expression (p = 0.0456). Riluzole improved erectile function via possibly interacting with PKC β II and glutamatergic pathways, as a potential therapeutic candidate for erectile dysfunction.

Lacosamide alleviates bilateral cavernous nerve injury-induced erectile dysfunction in the rat model by ameliorating pathological changes in the corpus cavernosum

Bilateral cavernous nerve injury-related erectile dysfunction (BCNI-ED) shows a limited response to type 5 phosphodiesterase inhibitors. Furthermore, lacosamide (LCM) can alleviate peripheral neuropathy. To explore whether LCM can improve the erectile response after BCNI, we randomly divided 30 young Sprague-Dawley rats into three groups (n = 10 per group), namely, the sham operation, 0.9% normal saline-treated (BCNI + 0.9% NS), and LCM-treated BCNI (BCNI + LCM) groups. LCM was injected intraperitoneally at a dose of 90 mg/kg/day for 7 consecutive days. Erectile function was assessed by measuring the ratio of peak intracavernous pressure (ICP) to mean arterial pressure (MAP), and tissues were harvested for transmission electron microscopy, immunofluorescence, Masson's trichrome staining, TUNEL staining, and Western blot analysis. The BCNI + 0.9% NS group showed reduced ICP/MAP ratio (0.93 ± 0.04 vs. 0.44 ± 0.05, P < 0.0001). An increased proportion of TUNEL-positive cells (0.04 ± 0.01 vs 0.87 ± 0.03, P < 0.0001) and a decreased smooth muscle/collagen ratio (0.44 ± 0.01 vs. 0.33 ± 0.01, P < 0.001) were observed in the BCNI + 0.9% NS compared with the sham group. Administration of LCM significantly restored the ICP/MAP ratio (0.44 ± 0.05 vs. 0.74 ± 0.05, P < 0.001) and decreased the proportion of TUNEL positive cells (0.87 ± 0.03 vs. 0.60 ± 0.04, P < 0.0001) in the corpus cavernosum following BCNI. The ratio of smooth muscle to collagen (0.43 ± 0.01vs. 0.33 ± 0.01, P < 0.01) and expression of α-SMA (P < 0.0001) in the BCNI + LCM group significantly increased compared with BCNI + 0.9% NS group, indicating alleviation of fibrosis. Apoptotic markers, including Bax/Bcl-2 (P < 0.01) and Caspase-3 (P < 0.0001) in the BCNI + LCM group was significantly lower than that in the BCNI + 0.9% NS group. LCM treatment partially upregulated the expression of vWF and eNOS in cavernous tissue in rats subjected to BCNI (P < 0.05). Increases in S100-β and nNOS expression in the major pelvic ganglion (MPG) were observed after LCM administration. In summary, LCM can recover erectile function in BCNI-ED rat model by suppressing corporal apoptosis and fibrosis, and protecting the cavernous nerve.

Adipose Derived Mesenchymal Stem Cells-Derived Mitochondria Transplantation Ameliorated Erectile Dysfunction Induced by Cavernous Nerve Injury

PURPOSE

Erectile dysfunction (ED) is a common postoperative complication of pelvic surgery for which there is currently no effective treatment. This study investigated the therapeutic effects and potential mechanisms of adipose derived mesenchymal stem cells-derived mitochondria (ADSCs-mito) transplantation in a rat model of bilateral cavernous nerve injury (CNI) ED.

MATERIALS AND METHODS

We isolated mitochondria from ADSCs and tested their quality. In vivo, twenty male Sprague Dawley rats were randomly divided into four groups: sham operation group and CNI groups that received intracavernous injection of either phosphate buffer solution, ADSCs-mito or ADSCs. Two weeks after therapy, the erectile function of the rats was evaluated and the penile tissues were harvested for histologic analysis and western blotting. In vitro, the apoptosis rate, reactive oxygen species (ROS), mitochondria derived active oxygen (mtROS) and adenosine triphosphate (ATP) levels were detected in corpus cavernosum smooth muscle cells (CCSMCs) after the incubation with ADSCs-mito. In addition, intercellular mitochondrial transfer was visualized by co-culture of ADSCs and CCSMCs.

RESULTS

The ADSCs, ADSCs-mito and CCSMCs were isolated and identified successfully. ADSCs-mito transplantation notably restored the erectile function and smooth muscle content of CNI ED rats. Moreover, the levels of ROS, mtROS and cleaved-caspase 3 were reduced and the levels of superoxide dismutase and ATP were increased after ADSCs-mito transplantation. In CNI ED rats, the mitochondrial structure of cells in penile tissues was destroyed. ADSCs could transfer its own mitochondria to CCSMCs. Pre-treatment with ADSCs-mito could significantly decrease apoptosis rate, ROS levels and mtROS levels as well as restore the ATP level in CCSMCs.

CONCLUSIONS

ADSCs-mito transplantation significantly ameliorated ED induced by CNI, with similar potency to ADSCs treatment. The ADSCs-mito might exert their effects via anti-oxidative stress, anti-apoptosis and modulating energy metabolism of CCSMCs. Mitochondrial transplantation should be a promising therapeutic method for treating CNI ED in the future.

Platelet-rich Plasma for the Treatment of Erectile Dysfunction: A Prospective, Randomized, Double-blind, Placebo-controlled Clinical Trial

PURPOSE

We assessed the safety and efficacy of 2 injections of platelet-rich plasma for treating mild to moderate erectile dysfunction by conducting a prospective, randomized, double-blind, placebo-controlled clinical trial.

MATERIALS AND METHODS

Men with mild to moderate erectile dysfunction (International Index of Erectile Function scores 11-25) were randomized to receive either 2 injections of platelet-rich plasma or placebo separated by 1 month. Primary outcome was percentage of men meeting minimum clinically important difference at 1 month after the second injection. Secondary outcomes were change in International Index of Erectile Function at 1, 3, and 6 months, and changes in penile vascular parameters and adverse events at 6 months.

RESULTS

We randomized 61 men: 28 into platelet-rich plasma and 33 into placebo. There was no difference between groups in percentage of men meeting minimum clinically important difference at 1 month: 14 (58.3%) in platelet-rich plasma vs 15 (53.6%) in placebo (P = .730). Mean International Index of Erectile Function-Erectile Function domain changed from 17.4 (95% CI 15.8-19.0) to 21 (17.9-24.0) at 1 month in men receiving platelet-rich plasma, vs 18.6 (17.3-19.8) to 21.6 (19.1-24.1) in the placebo group; however, there was no significant difference between groups (P = .756). There were no major adverse events and only 1 minor adverse event in each group. There were no changes in penile Doppler parameters from baseline to 6 months.

CONCLUSIONS

The results of our prospective, double-blind, randomized, placebo-controlled clinical trial suggest that 2 injections of intracavernosal platelet-rich plasma separated by 1 month in men with mild to moderate erectile dysfunction is safe, but we found no difference in efficacy between platelet-rich plasma and placebo.

Is Platelet Rich Plasma Safe and Effective in Treatment of Erectile Dysfunction? Randomized Controlled Study

OBJECTIVE

To evaluate the safety and efficacy of platelet rich plasma (PRP) injections as a therapeutic modality for mild to moderate erectile dysfunction.

METHODS

A placebo-controlled study of 100 cases with mild to moderate erectile dysfunction. Participants were allocated to 2 groups; the PRP group received 3 injections (3 mL each corpus) and the interval between injections was 15 days, while the Placebo (Saline) group received 6 mL saline injected intracavernous. Postinjection follow-up lasted 6 months.

RESULTS

Compared to the placebo group, the PRP group demonstrated a significant improvement at the 1 and 3 months follow-up that slightly dropped at the 6 months follow-up (P <.001). The improvement was evident in the duplex parameters, International Index of Erectile Function Erectile Function (IIEF-EF), SEP Q2, and 3. At 1-month post-treatment follow-up (76%) patients in the PRP group had an improved IIEF-EF as they attained a minimal clinically important difference compared to (18%) in the saline group. At the 3-months post-treatment follow-up, (72%) patients achieved a minimal clinically important difference in the PRP group vs (16%) in saline group then dropped to (70%) in the PRP group vs (16%) in saline group at the 6-months post-treatment follow up. Patients' overall and intercourse satisfaction levels were higher in the PRP group than the placebo group as demonstrated with the higher IIEF score Q6, 7, 8, and IIEF score Q13, 14 respectively with the maximum improvement reported at the 3 months follow-up. No reports of plaque formation, subcutaneous bruising, or any other major side effects among participants.

CONCLUSION

PRP is a safe and promising method for the improvement of mild to moderate erectile dysfunction.

Erectile dysfunction and exosome therapy

Erectile dysfunction (ED), as a common male disease, can seriously reduce the life quality of men and their partners. With the improvement of human living standards, ED is considered to be an important health issue that plagues men. However, it is difficult for existing therapeutic approaches to meet the needs of all patients, so it is necessary to develop novel treatment strategies. Exosomes, as a class of vesicles secreted by cells with bilayer membrane structure, are involved in various physiological and pathological processes in human body and considered to have great therapeutic potentials. This review summarizes the recent advances on exosome therapy with animal models of ED, and proposes the prospect of future research in order to provide a basis for clinical trials and clinical translation.

Molecular pathogenesis and treatment of cavernous nerve injury-induced erectile dysfunction: A narrative review

Introduction: Erectile dysfunction (ED) is a common complication after radical prostatectomy (RP), and it seriously affects the quality of life in patients and their partners. The primary trigger of postoperative ED is surgical injury to the cavernous nerves that control penile erection and run along the anterolateral aspect of the prostate. Despite the introduction and ongoing innovation of nerve-sparing techniques, a significant number of patients still suffer from moderate cavernous nerve injury (CNI), which is thought to be transient and reversible. Therefore, early postoperative penile rehabilitation therapy may salvage patients’ erectile function by promoting cavernous nerve regeneration and preventing penile structural alterations.

Aims: To present a comprehensive overview of the current molecular pathogenesis of CNI-induced ED, as well as novel therapeutic strategies and their potential mechanisms.

Methods: A literature search was performed using PubMed. Search terms included erectile dysfunction, cavernous nerve injury, pathogenesis, pathway, and treatment.

Results: The NOS/NO pathway, oxidative stress-related pathway, RhoA/ROCK pathway, transforming growth factor-β (TGF-β), sonic hedgehog (Shh), and hydrogen sulfide (H2S) are involved in the molecular pathogenesis of CNI-induced ED. Multiple neurotrophins, including brain-derived nerve growth factor (BDNF), glial cell line-derived neurotrophic factor (GDNF), and neurturin (NTN), were found to promote cavernous nerve regeneration. Emerging therapeutic approaches can be roughly summarized into four categories, namely small molecule and drug, stem cell-based therapy (SCT), micro-energy therapy and platelet-rich plasma (PRP) therapy.

Conclusion: These pathways collectively lead to the irreversible damage to the penile structure after CNI. The combined early rehabilitation strategies of promoting upstream nerve regeneration and recovering abnormal molecular signals of downstream penis are presumed to save patients’ erectile function after RP. In future studies, the cross-talk between these molecular pathways needs to be further clarified, and the questions of how denervation injury induces the molecular alterations in the penis also need to be addressed.

Curcumin slow-release membrane promotes erectile function and penile rehabilitation in a rat model of cavernous nerve injury

Male erectile dysfunction (ED) caused by cavernous nerve injury is a common complication of pelvic surgery, radiotherapy, transurethral surgery or other operations. However, clinical treatment for iatrogenic or traumatic male ED is difficult and not satisfactory. Many studies have shown that curcumin can promote the repair and regeneration of peripheral nerves; however, whether curcumin can rescue cavernous nerve injury is unknown, and the poor bioavailability of curcumin limits its application in vivo. Hence, the study was conducted. A curved slow-release membrane was produced, and the properties were examined. In addition, the effects of the curcumin slow-release membrane on cavernous nerve-injured SD rats were studied. We found that polylactic acid-glycolic acid-polyethylene glycol (PLGA-PEG) can be used as a good carrier material for curcumin, and curcumin-loaded PLGA-PEG membranes can effectively rescue the cavernous nerve in SD rats, restore the continuity of the cavernous nerve, and increase the expression of nNOS mRNA and proteins in penile tissue, which can improve the penile erectile function of injured SD rats, reduce the degree of penile tissue fibrosis, and effectively promote penis rehabilitation. The curcumin slow-release membrane is proposed to be a new therapeutic approach for penile rehabilitation of cavernous nerve injury.

The potential of platelet-rich plasma injections and stem cell therapy for penile rejuvenation

Penile concerns include erectile dysfunction (ED) and Peyronie disease (PD). Restorative therapies including Stem Cell Therapy (SCT) and Platelet Rich Plasma (PRP) injections are proposed to treat these concerns. SCT encompasses the harvesting and injection of mesenchymal stem cells or stromal vascular fractions from various tissue sources. PRP is derived autologously from a patient's plasma and is then injected into the penile tissue. These therapies repair damaged penile tissue and promote both new cellular and vascular growth, as demonstrated in basic science studies. Human trials on SCT and PRP for both ED and PD and have yielded promising results with few side effects. While encouraging, small cohort size and lack of blinding or placebo control limit these studies' external validity. Recently, the first double-blinded randomized controlled trial on PRP for ED was published, providing significant evidence of efficacy. With the rapid commercial availability of SCT and PRP for ED and PD, it is imperative to perform more randomized and placebo-controlled trials with standardized procedures and preparations to evaluate efficacy and safety. This narrative review will summarize the available literature on these penile restorative therapies to date.

Cavernous Nerve Injury Resulted Erectile Dysfunction and Regeneration

Erectile dysfunction (ED) is an important cause of reduced quality of life for men and their partners. Recent studies have found that cavernous nerve injury (CNI) during prostate cancer surgery and other pelvic surgery results in medically induced CNIED in more than 80% of patients. The efficacy of first- and second-line treatment options for ED is poor. A great deal of research has been devoted to exploring new methods of neuroprotection and nerve regeneration to save erectile function in patients with CNIED, especially in patients with cavernous nerve injury after prostate cancer surgery. In addition, such as neuromodulatory proteins, proimmune ligands, gene therapy, stem cell therapy, and the current cutting-edge low-energy shock wave therapy have shown advantages in basic research and limited clinical studies. In the context of today's modern medicine, these new therapeutic techniques are expected to be new tools in the treatment of cavernous nerve injury erectile dysfunction. This article presents the main causes, mechanisms, and treatment of cavernous nerve injury erectile dysfunction and combines them with new treatment strategies.

A review of regenerative therapies as penile rehabilitation in men following primary prostate cancer treatment: Evidence for erectile restoration and cavernous nerve regeneration

Objective

Methods

Results

Conclusion

Canadian Urological Association guideline: Erectile dysfunction

Erectile dysfunction (ED) impacts the wellness and quality of life of millions of Canadians. An evaluation focused on the identification of reversible and irreversible underlying factors is recommended for patients presenting with ED. Through a shared decision-making model framework, the goal of ED treatment is to improve functional outcomes and enhance sexual satisfaction while minimizing adverse effects associated with treatment. Given that ED is assessed and treated by multiple different types of health practitioners, the purpose of this guideline is to provide the best available evidence to facilitate care delivery through a Canadian lens. After a narrative review of ED assessment and treatment for general readership, five key clinical questions relating to priority areas of ED are assessed using the GRADE and evidence-to-decision-making frameworks.

Acute spinal cord injury: Pathophysiology and pharmacological intervention (Review)

Spinal cord injury (SCI) is one of the most debilitating of all the traumatic conditions that afflict individuals. For a number of years, extensive studies have been conducted to clarify the molecular mechanisms of SCI. Experimental and clinical studies have indicated that two phases, primary damage and secondary damage, are involved in SCI. The initial mechanical damage is caused by local impairment of the spinal cord. In addition, the fundamental mechanisms are associated with hyperflexion, hyperextension, axial loading and rotation. By contrast, secondary injury mechanisms are led by systemic and cellular factors, which may also be initiated by the primary injury. Although significant advances in supportive care have improved clinical outcomes in recent years, a number of studies continue to explore specific pharmacological therapies to minimize SCI. The present review summarized some important pathophysiologic mechanisms that are involved in SCI and focused on several pharmacological and non‑pharmacological therapies, which have either been previously investigated or have a potential in the management of this debilitating injury in the near future.

Role of regenerative therapies on erectile dysfunction after radical prostatectomy

The present study provides a review of stem cell therapy as a treatment of erectile dysfunction from peer-reviewed human and animal trials. A literature search was conducted in PubMed-Medline, Scopus, Embase, and Cochrane databases. Tweenty-three animal studies and seven human studies in the period from 1st of January 2000 to 1st of Mai 2020 were included. The seven included human studies are primary phase one trials, and most of them treat erectile dysfunction following radical prostatectomy by injection of stem cells into the corpus cavernosum. The primary outcome measure in all human trials is safety and secondary can stem cells play a role in the recovery of erectile function. All studies conclude that it is safe to use stem cells and the majority of the studies demonstrate an improvement in erectile function. The results from both animal and human trials are promising for stem cells as a restorative treatment, but data from large randomized human phase two trials is missing before it can be concluded, that stem cells is an effective treatment for erectile dysfunction in humans.

Male sexual dysfunction and rehabilitation strategies in the settings of salvage prostate cancer treatment

Male sexual dysfunction, a common sequela following primary prostate cancer (PC) treatment, is likely to be more significant following salvage PC therapy. In general, these impairments in sexual domains can be divided into three groups, namely (1) sexual desire, sexuality and masculinity; (2) erectile function (EF); and (3) ejaculation and orgasm. However, there is considerable overlap between these sexual domains and male sexual response cycle, and various factors such as cancer status, mental well-being, medical conditions and social circumstances can adversely impact on the male sexual function. While several preventive and treatment strategies for the preservation and recovery of sexual function are available, there is limited consensus guidelines exist regarding the optimal rehabilitation or treatment protocol for men with sexual dysfunction following salvage therapy. While penile rehabilitation may be effective to restore erectile function and the ability to have coital sex, there is lack of effective treatments in other domains of male sexual function, thereby underscoring the importance of psychological and sexual counselling in sexual rehabilitation. Indeed, a comprehensive multidisciplinary approach is necessary to better understand and optimally assist and manage the men and their respective partners for better sexual health and activity.

Erectile Dysfunction A Prospective Randomized Placebo-Controlled Study Evaluating the Effect of Low-Intensity Extracorporeal Shockwave Therapy (LI-ESWT) in Men With Erectile Dysfunction Following Radical Prostatectomy

Introduction

Previous studies have indicated that low-intensity extracorporeal shockwave therapy (Li-ESWT) may improve male erectile dysfunction (ED) of vascular aetiology.

Aim

To investigate penile rehabilitation of Li-ESWT in a randomized, placebo-controlled trial in men with ED following robotic nerve-sparing radical prostatectomy (RARP).

Methods

Included were men with ED following nerve-sparing RP with a score <22 in the 5-item International Index of Erectile Function (IIEF-5) questionnaire. Participants were divided into an active A (n = 20) and a placebo/sham B group (n = 18). They were randomized consecutively upon study entry. Each study arm had one treatment a week for 5 weeks.

Main outcome measures

Sexual outcomes were assessed by international validated questionnaires, Erection Hardness Score (EHS) and IIEF-5 at baseline and at 4 and 12 weeks after treatment.

Results

A total of 38 (n = 38) participants were enrolled; there were no dropouts. A significant increase was observed in IIEF-5 and EHS in group A at both 4 and 12 weeks. At 12 weeks, the mean IIEF-5 score had increased by 3.45 points (P = .026), while the mean EHS score had increased by 0.5 points (P= .019).

Conclusion

This randomized study indicates that Li-ESWT for ED in men undergone RP might be effective and safe. However, further and more robust research is needed before Li-ESWT can be characterized as a reliable treatment modality. Ladegaard PBJ, Mortensen J, Skov-Jeppesen SM, et al. Erectile Dysfunction A Prospective Randomized Placebo-Controlled Study Evaluating the Effect of Low-Intensity Extracorporeal Shockwave Therapy (LI-ESWT) in Men With Erectile Dysfunction Following Radical Prostatectomy. Sex Med 2021;9:100338.

Early Clinical Results of the Tolerability, Safety, and Efficacy of Autologous Platelet-Rich Plasma Administration in Erectile Dysfunction

Introduction

Platelet-rich plasma (PRP) is useful in the treatment of different conditions and diseases as it contains concentrated levels of many growth factors.

Aim

The aim of this study was to investigate the effectiveness of autologous PRP application in the treatment of erectile dysfunction (ED) in patients with metabolic syndrome.

Methods

In this prospective study conducted in June 2019, 31 patients with ED were included. The International Index of Erectile Function–Erectile Function domain (IIEF-EF) questionnaires were used to evaluate erectile function (EF). After administering the intracavernous autologous PRP 3 times with an interval of 15 days, IIEF-EFs were evaluated 1, 3, and 6 months later.

Main Outcome Measure

IIEF in the 1st, 3rd, and 6th months and adverse events.

Results

While the mean IIEF-EF was 18 before the application, the mean IIEF-EF was 20 in the first, third, and sixth months after the procedure (P < .001). However, even though IIEF-EF values increased numerically, median value remained within the mild-moderate classification (scores between 17 and 21). Postprocedure sexual satisfaction scores were significantly higher than preprocedure values (8 vs 6, respectively; P = .002). In the first follow-up of a patient after the 3rd injection, a 4-mm diameter fibrotic plaque was observed on the ventral side in the middle of the penis shaft.

Conclusion

In conclusion, our findings suggest that larger studies as well as placebo-controlled studies are needed to add PRP to the treatment protocol in ED.

T Taş,Çakıroğlu, E Arda, et al. Early Clinical Results of the Tolerability, Safety, and Efficacy of Autologous Platelet-Rich Plasma Administration in Erectile Dysfunction. Sex Med 2021;9:100313.

Local continuous glial cell derived neurotrophic factor release using osmotic pump promotes parasympathetic nerve rehabilitation in an animal model of cavernous nerve injury induced erectile dysfunction

Background

Nerve injury-related erectile dysfunction (ED) is one of the types that respond poorly to conventional ED treatments. Our previous experiments have demonstrated the paracrine of various neurotrophic factors (NTFs) by stem cells or other treatment modalities as a potential mechanism in the recovery of nerve injury-related ED. Glial cell derived neurotrophic factor (GDNF) is one of the essential NTFs for the regeneration of nerve fibers, especially for parasympathetic nerves. The aim of this study is to explore if local continuous GDNF administration is beneficial for the functional and histological recovery of nerve injury induced ED.

Methods

Eight-week-old male Sprague-Dawley rats were used for this study. Rats were randomly grouped into 5: Sham surgery (Sham), bilateral cavernous nerve injury (BCNI) and placebo treatment, BCNI and 0.1 µg/100 µL GDNF treatment (BCNI+GDNF 0.1), BCNI and 1 µg/100 µL GDNF treatment (BCNI+GDNF 1), BCNI and 10 µg/100 µL GDNF treatment (BCNI+GDNF 10). GDNF was administered using an osmotic pump technique which would deliver GDNF locally and continuously for 28 days without the need for external connections or frequent handling of animals. Recovery of sexual function, nerve fibers regeneration, and expression of neurotrophic receptors were examined and compared among groups after the treatment.

Results

Local continuous GDNF release treatment increased the average number of intromissions in the sexual behavior test and intracavernous pressure (ICP) in the erectile function test in a dose dependent manner. Osmotic pump implantation induced increased local GDNF concentration and mild inflammatory response. Gene expression of GDNF receptors in major pelvic ganglion (MPG) and nerve regeneration along the urethra were partially promoted by GDNF. These changes were associated with increased nerve fibers especially the parasympathetic nerve fibers in dorsal nerve of penis (DNP) in GDNF treated groups.

Conclusions

In conclusion, our project illustrated the promising effects of local continuous GDNF administration for the functional and histological recovery of nerve injury-induced ED.

Availability of platelet-rich plasma for treatment of erectile dysfunction and associated costs and efficacy: A review of current publications and Canadian data

INTRODUCTION

Platelet-rich plasma (PRP) is an increasingly used unconventional treatment option for erectile dysfunction (ED). The validity of PRP as a potential treatment for ED has been proposed in limited human trials. Furthermore, the costs associated with PRP for ED treatment are not readily promoted to patients. The goal of this review was to determine the efficacy and costs of PRP based on currently available literature and Canadian data.

METHODS

A comprehensive literature review of available PRP studies and current published data pertaining to cost, availability, and provider clinics globally was conducted using the PubMed database. Physicians offering genital PRP in Canada were identified using internet searches and PRP provider directories. Physician qualifications, clinic locations, and cost information were obtained from provider websites and telephone calls to identified clinics.

RESULTS

Availability of PRP injections offered for treating ED is increasing globally. There are currently no peer-reviewed publications to substantiate anecdotal evidence pertaining to the efficacy of PRP as a viable treatment option for ED patients. Our results indicate 19 providers for PRP injections in Canada, costing on average $1777 CAD per injection. No providers were affiliated with academic institutions and providers varied in their area of clinical speciality and training.

CONCLUSIONS

To our knowledge, there is currently no research underway investigating the clinical efficacy of PRP for ED treatment despite its broad availability and significant cost. Patients should be informed of the lack of substantiated efficacy and safety data, as the reliability of PRP treatments requires further evaluation.

Pericyte-Derived Extracellular Vesicle-Mimetic Nanovesicles Restore Erectile Function by Enhancing Neurovascular Regeneration in a Mouse Model of Cavernous Nerve Injury

BACKGROUND

Extracellular vesicle (EV)-mimetic nanovesicles (NVs) from embryonic stem cells have been observed to stimulate neurovascular regeneration in the streptozotocin-induced diabetic mouse. Pericytes play important roles in maintaining penile erection, yet no previous studies have explored the effects of pericyte-derived NVs (PC-NVs) in neurovascular regeneration in the context of erectile dysfunction.

AIM

To investigate the potential effect of PC-NVs in neurovascular regeneration.

METHODS

PC-NVs were isolated from mouse cavernous pericytes, and neurovascular regeneration was evaluated in an in vitro study. Twelve-week-old C57BL/6J mice were used to prepare cavernous nerve injury model. Erectile function evaluation, histologic examination of the penis, and Western blots were assessed 2 weeks after model creation and PC-NVs treatment.

OUTCOMES

The main outcomes of this study are PC-NVs characterization, intracavernous pressure, neurovascular regeneration in the penis, and in vitro functional evaluation.

RESULTS

The PC-NVs were extracted and characterized by cryotransmission electron microscopy and EV-positive (Alix, TSG101, CD81) and EV-negative (GM130) markers. In the in vivo studies, PC-NVs successfully improved erectile function in cavernous nerve injury mice (∼82% of control values). Immunofluorescence staining showed significant increases in pericytes, endothelial cell, and neuronal contents. In the in vitro studies, PC-NVs significantly increased mouse cavernous endothelial cells tube formation, Schwann cell migration, and dorsal root ganglion and major pelvic ganglion neurite sprouting. Finally, Western blot analysis revealed that PC-NVs upregulated cell survival signaling (Akt and eNOS) and induced the expression of neurotrophic factors (brain-derived neurotrophic factor, neurotrophin-3, and nerve growth factor).

CLINICAL IMPLICATIONS

PC-NVs may be used as a strategy to treat erectile dysfunction after radical prostatectomy or in men with neurovascular diseases.

STRENGTHS & LIMITATIONS

We evaluated the effect of PC-NVs in vitro and in a mouse nerve injury model, cavernous nerve injury. Additional studies are necessary to determine the detailed mechanisms of neurovascular improvement. Further study is needed to test whether PC-NVs are also effective when given weeks or months after nerve injury.

CONCLUSION

PC-NVs significantly improved erectile function by enhancing neurovascular regeneration. Local treatment with PC-NVs may represent a promising therapeutic strategy for the treatment of neurovascular diseases. Yin GN, Park S-H, Ock J, et al. Pericyte-Derived Extracellular Vesicle-Mimetic Nanovesicles Restore Erectile Function by Enhancing Neurovascular Regeneration in a Mouse Model of Cavernous Nerve Injury. J Sex Med 2020;17:2118-2128.

Electrical stimulation for neuroregeneration in urology: a new therapeutic paradigm

PURPOSE OF REVIEW

The present review highlights regenerative electrical stimulation (RES) as potential future treatment options for patients with nerve injuries leading to urological dysfunction, such as urinary incontinence, voiding dysfunction or erectile dysfunction. Additionally, it will highlight the mechanism of nerve injury and regeneration as well as similarities and differences between RES and current electrical stimulation treatments in urology, functional electrical stimulation (FES) and neuromodulation.

RECENT FINDINGS

It has been demonstrated that RES upregulates brain-derived neurotrophic factor (BDNF) and its receptor to facilitate neuroregeneration, facilitating accurate reinnervation of muscles by motoneurons. Further, RES upregulates growth factors in glial cells. Within the past 2 years, RES of the pudendal nerve upregulated BDNF in Onuf's nucleus, the cell bodies of motoneurons that course through the pudendal nerve and accelerated functional recovery in an animal model of stress urinary incontinence. Additionally, electrical stimulation of the vaginal tissue in an animal model of stress urinary incontinence accelerated functional recovery.

SUMMARY

RES has great potential but future research is needed to expand the potential beneficial effects of RES in the field of urology.

The good, bad, and the ugly of regenerative therapies for erectile dysfunction

Erectile dysfunction (ED) is a common condition which reduces quality of life of both patients and their partners, and is a significant health care expense every year. Although phosphodiesterase type-5 inhibitors are the current first-line treatment for men with ED, they are limited by their on-demand dosing, intolerance, and variable efficacy in complex patient populations such as men with multiple medical comorbidities or ED after pelvic surgery. Regenerative medicine has been introduced and investigated in andrology as an encouraging strategy to restore diseased erectile tissue structure and function. Novel regenerative therapies for ED are controversial but are perceived to offer a durable and safe tissue restorative approach to act as a long-term solution to this cumbersome disease process. Here, we review platelet-rich plasma, amniotic fluid membranes, low-intensity extracorporeal shockwave therapy, and stem cell therapy as regenerative strategies to treat ED. Most of these approaches have preclinical and occasionally clinical data to support their ongoing investigation; however, none of these treatments are currently supported for use in ED patients outside of clinical trials.

Valproate, sexual health, and men: A narrative review

OBJECTIVE

This article explores current evidence about the effects of valproate (VPA) medicines on sexual health in men, how to monitor symptoms, communicate with patients, and improve clinical outcomes. There has been a lot of focus on VPA use in women of childbearing age following recent changes to prescribing regulations owing to the well-established and significant teratogenic risk. Concerns have been raised by patients and clinicians as to the risk of adverse sexual effects of VPA use in men.

RESULTS

The evidence base for the effect of VPA on sexual function compared with other antiepileptic drugs (AEDs) in men is limited with no randomized controlled trials. Sexual function in men with epilepsy is complex, and there is no direct relationship between objective measures of sexual function and sexual satisfaction. Epilepsy, comorbidities, psychosocial factors, and most AEDs including VPA may cause sexual dysfunction in men, including reduced sexual desire, erectile dysfunction, and fertility problems. Sexual and reproductive function should be discussed with men prior to treatment with AEDs including VPA.

CONCLUSION

Early and proactive discussion of sexual and reproductive functioning mitigates, rather than increases, the risk of sexual problems and potentially improves adherence. Sexual dysfunction in men with cognitive impairment [such as intellectual disability (ID) and dementia] may present with behavioral disturbance. Identification of sexual adverse effects of medication could significantly change treatment plans which is of particular importance for individuals with treatment resistance. We provide an information fact sheet for men to help guide prescribing discussions.

[Exogenous hydrogen sulfide improves erectile dysfunction by inhibiting apoptosis of corpus cavernosum smooth muscle cells in rats with cavernous nerve injury]

OBJECTIVE

To explore the effects of exogenous hydrogen sulfide (H2S) on apoptosis of corpus cavernosum smooth muscle cells (CCSMCs) and erectile dysfunction (ED) in rats with bilateral cavernous nerve injury (BCNI).

METHODS

Twentyfour male SD rats were randomly divided into 3 groups (n=8):sham operation group, bilateral cavernous nerve injury group (BCNI group) and H2S intervention group (BCNI+NaHS group). In BCNI and BCNI+NaHS groups, BCNI was induced by clamp injury of the bilateral cavernous nerves, and the rats were subjected to daily intraperitoneal injection of normal saline and 100 μmol/kg NaHS solution for 4 weeks, respectively. After the treatment, the intracavernous pressure (ICP) and mean arterial pressure (MAP), ) of the rats were measured. Western blotting was used to detect the expressions of cystathionine β synthetase (CBS), cystathionine γ lyase (CSE), α-SMA, collagen-I, caspase-3, Bax and Bcl-2 in the penile cavernous tissue, and the expressions of CBS and CSE were also detected immunohistochemically. The ratio of cavernous smooth muscle to collagen was detected using Masson's Trichrome staining. The apoptosis level of CCSMC was detected by TUNEL + α-SMA immunofluorescence double staining.

RESULTS

After 4 weeks of treatment, the rats in BCNI+NaHS group showed a significantly higher ICP/MAP ratio than those in BCNI group (P < 0.05). The results of Masson's Trichrome staining showed that the ratio of cavernous smooth muscle/collagen was significantly higher in BCNI + NaHS group than in BCNI group (P < 0.05). Western blotting showed a significantly higher expression of α-SMA protein but a lower expression of collagen-I protein in BCNI + NaHS group than in BCNI group (P < 0.05). TUNEL+α-SMA immunofluorescence double staining revealed a significantly lower number of apoptotic CCSMCs in BCNI+NaHS group than in BCNI group (P < 0.05). Compared with those in BCNI group, the rats in BCNI+NaHS group had significantly decreased expressions of caspase-3 and Bax proteins (P < 0.05) with significantly enhanced Bcl-2 protein expression and an increased Bcl-2/Bax ratio (P < 0.05). The expressions of CBS and CSE were significantly lower in BCNI group than in the other two groups (P < 0.05).

CONCLUSIONS

Exogenous H2S enhance the expression of the classic apoptotic protein Bcl-2 and reduces apoptosis of CCSMC to improve the erectile function in rats with BCNI.

IcarisideII facilitates the differentiation of ADSCs to SCs via let-7i/STAT3 axis to preserve erectile function

BACKGROUND

IcarisideII (ICAII) could promote the differentiation of adipose tissue-derived stem cells (ADSCs) to Schwann cells (SCs), leading to improvement of erectile function (EF) and providing a realistic therapeutic option for the treatment of erectile dysfunction (ED). However, the underlying molecular mechanisms of ADSCs and ICAII in this process remain largely unclear.

METHODS

ADSCs were treated with different concentrations of ICAII. Cell proliferation was determined by MTT assay. qRT-PCR and western blot were performed to detect expressions of SCs markers, signal transducer and activator of transcription-3 (STAT3), and microRNA-let-7i (let-7i). Luciferase reporter assay was conducted to verify the regulatory relationship between let-7i and STAT3. The detection of intracavernosal pressure (ICP) and the ratio of ICP/mean arterial pressure (MAP) were used to evaluate the EF in bilateral cavernous nerve injury (BCNI) rat models.

RESULTS

ICAII promoted cell proliferation of ADSCs in a dose-dependent manner. The mRNA and protein levels of SCs markers were increased by ICAII treatment in a dose-dependent manner in ADSCs. Moreover, let-7i was significantly decreased in ICAII-treated ADSCs and upregulation of let-7i attenuated ICAII-induced promotion of SCs markers. In addition, STAT3 was a direct target of let-7i and upregulated in ICAII-treated ADSCs. Interestingly, overexpression of STAT3 abated the let-7i-mediated inhibition effect on differentiation of ADSCs to SCs and rescued the ICAII-mediated promotion effect on it. Besides, combination treatment of ADSCs and ICAII preserved the EF of BCNI rat models, which was undermined by let-7i overexpression.

CONCLUSION

ICAII was effective for preserving EF by promoting the differentiation of ADSCs to SCs via modulating let-7i/STAT3 pathway.

Effect of HongJing I in Treating Erectile Function and Regulating RhoA Pathway in a Rat Model of Bilateral Cavernous Nerve Injury

HongJing I (HJI), a traditional Chinese herbal formula, has been confirmed to be effective for the clinical treatment of erectile dysfunction (ED). However, the mechanism of action of HJI remains unclear. Here, we aimed to investigate the effect and underlying mechanisms of HJI against ED in a rat model of bilateral cavernous nerve injury (BCNI). Rats were divided into five groups: normal control (NC), BCNI-induced ED model (M), M + low-dose HJI (HL), M + medium-dose HJI (HM), and M + high-dose HJI (HH). All groups were treated with normal saline or the relevant drug for 28 consecutive days after inducing BCNI-ED. At the end of the treatment period, the intracavernous pressure (ICP) was recorded, and histological examination was conducted using Masson's trichrome staining. Immunofluorescence staining and western blotting were applied to detect the changes in fibrosis protein and Ras homolog A (RhoA), Rho-associated protein kinase 1 (ROCK1), and ROCK2 expression. We found that HJI effectively improved the ICP in the treatment groups. In addition, RhoA, ROCK1, and ROCK2 expression levels were increased upon BCNI-ED induction, and HJI successfully inhibited cavernosum fibrosis and the activation of RhoA/ROCK2 signaling. Overall, these results suggest that the effects of HJI in attenuating ED may be caused, at least in part, by the suppression of RhoA/ROCK2 signaling and alleviation of fibrosis. However, the precise mechanism surrounding this requires further investigation in future studies.

Extracorporeal shock wave therapy decreases COX-2 by inhibiting TLR4-NFκB pathway in a prostatitis rat model

BACKGROUND

This study aims to evaluate the effect of extracorporeal shock wave therapy (ESWT) on chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) and to explore the mechanism.

METHODS

RWPE-2 cells were randomly divided into three groups: (a) RWPE-2 group (normal control), (b) LPS groups (lipopolysaccharide inducing inflammation) and (c) ESWT groups (LPS induced RWPE-2 treated by ESWT). After ESWT was administered, cells and supernatant were collected for enzyme-linked immunosorbent assay (ELISA) and Western blot analysis. In vivo, Sprague-Dawley rats (n = 30) were randomly divided into three groups: (a) normal control group, (b) prostatitis groups, and (c) ESWT groups. Prostatitis rats were induced by 17 β-estradiol and dihydrotestosterone for 4 weeks. After ESWT, prostates of each group were collected for immunohistochemistry, Western blot analysis, and ELISA.

RESULTS

ESWT improved prostatitis by attenuating inflammation (P < .01). ESWT downregulated the expression of cyclooxygenase 2 (COX-2) through inhibiting TLR4-NFκB pathway compared with the LPS group in vitro or prostatitis group in vivo (P < .05). TRAF2 mediates ERK1/2-COX2 pathway. ESWT promotes prostate tissue recovery by stimulating vascular endothelial growth factor expression (P < .01). ESWT could suppress apoptosis in the prostate.

CONCLUSIONS

ESWT improved CP/CPPS and reduced inflammation by degrading COX-2 in microenvironment through TLR4-NFκB-inhibiting pathway. TRAF2 regulator in ERK1/2-COX-2 inhibition significantly reduced inflammation, thus suggesting ESWT may be a potential and promising treatment for CP/CPPS.

Efficacy and safety of novel low-intensity pulsed ultrasound (LIPUS) in treating mild to moderate erectile dysfunction: a multicenter, randomized, double-blind, sham-controlled clinical study

Background

In our previous study, a novel low-intensity pulsed ultrasound (LIPUS) therapeutic device has been shown to improve erectile function non-invasively in a diabetic-induced erectile dysfunction (ED) animal model.

Methods

In order to investigate the efficacy and safety of LIPUS in the clinical treatment of patients with ED, a multicenter, randomized, double-blind, sham-treated, controlled clinical study was conducted at five medical centers, and 120 patients with mild to moderate ED were enrolled in the study. Patients were randomized into a sham-treated control group (40 patients) or a LIPUS-treated group (80 patients). LIPUS or sham treatment was applied to both sides of the penis shaft and crus for 5 min in each area, twice a week for four weeks. Assessment of efficacy and safety were evaluated using IIEF-5, Sexual Encounter Profile (SEP)-questionnaires 2/3, Global Assessment Question (GAQ), Erectile Hardness Score (EHS), Erection Quality Scale (EQS) score, and pain assessment [Visual Analogue Scale/Score (VAS)].

Results

Ten patients in LIPUS treatment group and 6 patients in sham treatment control group were excluded and the dropout rate is 13.33%. Response to treatment was identified as IIEF-5 score increased more than 2/3/4 points of post-treatment (12W) compared to pre-treatment (0W). The response rate in treatment group was 54/80 (67.50%), which was significantly higher than control group 8/40 (20.00%) at 12 weeks (FAS analysis). The percentage of patients with positive answers to SEP-3 (successful vaginal intercourse) were 58.97%, 64.1%, and 73.08% 4, 8, and 12 weeks after treatment which were significantly higher than 28.95%, 31.58%, and 28.95% respectively in control group (FAS, P<0.05). The positive responsive rates for GAQ in treatment group were about 2 to 3 times of that in control group (P<0.05). No treatment-related adverse events (AEs) were found, including local petechia or ecchymosis and hematuria.

Conclusions

Current study indicates that LIPUS can safely and effectively treat patients with mild to moderate ED without significant AEs, which is related to the mechanical force of LIPUS and can restore the pathological changes of the corpus cavernosum. LIPUS is a promising alternative treatment for ED treatment in the near future, while further research is remanded.

Effect of platelet-derived growth factor-BB on gap junction and connexin43 in rat penile corpus cavernosum smooth muscle cells

We explored whether platelet-derived growth factor (PDGF)-BB regulates corpus cavernosum smooth muscle cell gap junctions and can ameliorate erectile dysfunction and how it modulates connexin43 (CX43) after bilateral cavernous neurectomy. Primary cultured rat corpus cavernosum smooth muscle cells were treated with PDGF-BB with or without a PDGFR inhibitor, Akt siRNA or the depletion or promotion of β-catenin. PDGF-BB improved CCSMCs gap junction coupling and increased CX43 and PDGFRβ expression; inhibition of PDGFR activity down-regulated CX43 and decreased Akt and nuclear β-catenin. Knockdown or promotion of β-catenin down-regulated and up-regulated CX43 expression respectively. Moreover, β-catenin activation induced CX43 nuclear accumulation, which impeded CX43 down-regulation induced by PDGFR inhibition, suggesting that CX43 expression is positively correlated with nuclear β-catenin expression. Furthermore, CX43 promoter luciferase and chromatin immunoprecipitation assays indicated that β-catenin regulates CX43 transcription by directly interacting with its promoter. Male rats underwent bilateral cavernous neurectomy. After 12 weeks, they were injected with PDGF-BB, CX43 and PDGFRβ expression was significantly lower than in the control group, which was reversed by PDGF-BB injection. These results suggested that PDGF-BB contributed to the improvement of gap junction intracellular communication among corpus cavernosum smooth muscle cells, increased CX43 through PDGFRβ/Akt/nuclear β-catenin signalling, and ameliorated cavernous nerve injury-induced erectile dysfunction.