Low-intensity extracorporeal shock wave therapy for erectile dysfunction after radical prostatectomy: a review of preclinical studies

Comparison of the efficacy of the early LI-SWT plus daily tadalafil with daily tadalafil only as penile rehabilitation for postprostatectomy erectile dysfunction

This study compares the efficacy of the early low-intensity shock wave therapy (LI-SWT) plus daily tadalafil with daily tadalafil only therapy as penile rehabilitation for postprostatectomy erectile dysfunction in patients with prostate cancer who underwent bilateral interfascial nerve-sparing radical prostatectomy (robotic or open). From April 2019 to March 2021, 165 patients were enrolled, and 80 of them successfully completed this prospective study. Daily tadalafil were administered to all the patients. LI-SWT consisted of a total of six sessions. Each session was performed on days 4, 5, 6, and 7, and on the second and fourth weeks after surgery. Each LI-SWT session consisted of 300 shocks at an energy density of 0.09 mJ/mm2 and a frequency of 120 shocks per minute that were delivered at each of the five treatment points for 15 min. Thirty-nine patients were treated with tadalafil-only (group A) while 41 were treated with tadalafil and LI-SWT simultaneously (group B). At postoperative 6 months, the proportion of patients with erection hardness scores (EHS) ≥ 3 (4/39 vs. 12/41) was significantly higher in group B (p = 0.034), and LI-SWT was the only independent factor for predicting EHS ≥ 3 (OR, 3.621; 95% CI, 1.054-12.437; p = 0.041). There were no serious side effects related to early LI-SWT. Early LI-SWT plus daily tadalafil therapy as penile rehabilitation for postprostatectomy erectile dysfunction is thought to be more efficacious than tadalafil only. Further large-scaled randomized controlled trials will be needed to validate these findings.

Long-term efficacy of penile rehabilitation with low-intensity extracorporeal shock wave therapy for sexual and erectile function recovery following robotic-assisted radical prostatectomy: a single-cohort pilot study

Background

The long-term efficacy of low-intensity extracorporeal shock wave therapy (LIESWT) for penile rehabilitation after robot-assisted radical prostatectomy (RARP) has not yet been reported.

Aim

To assess the long-term efficacy of LIESWT for penile rehabilitation after RARP by evaluating the postoperative recovery of sexual and erectile functions following RARP.

Methods

Patients who underwent RARP at our institution were categorized into 2 groups: those who received LIESWT and those who underwent penile rehabilitation with a phosphodiesterase type 5 inhibitor (PDE5i). The control group included patients who did not undergo penile rehabilitation. Potency and scores on the Expanded Prostate Cancer Index Composite for sexual function and 5-item International Index of Erectile Function (IIEF-5) were evaluated preoperatively and over 60 months after RARP.

Outcomes

The LIESWT group had significantly higher postoperative sexual function and total IIEF-5 scores and potency than the control group over the long term, and its results were not inferior to those of the PDE5i group.

Results

The LIESWT, PDE5i, and control groups comprised 16, 13, and 139 patients, respectively. As compared with the control group, the LIESWT group had significantly higher sexual function scores at 6, 12, and 60 months after surgery (P < .05) and total IIEF-5 scores at 24 and 60 months (P < .05). The LIESWT group also had a significantly higher potency rate than the control group at 60 months (P < .05). For all time points after surgery, there were no significant differences between the LIESWT and PDE5i groups in terms of sexual function and total IIEF-5 scores and potency.

Clinical Implications

LIESWT may be a new option for penile rehabilitation in patients with erectile dysfunction after RARP.

Strengths and Limitations

This pilot study was performed at a single center and involved relatively few patients, which may have led to selection bias. Furthermore, the selection of this study for penile rehabilitation was not made randomly but by the patient's choice. Despite these limitations, our results provide evidence in support of LIESWT for penile rehabilitation after RARP because this is the first study to assess the long-term efficacy of LIESWT.

Conclusion

LIESWT can improve sexual and erectile functions in patients with erectile dysfunction after RARP, and its efficacy can be maintained over a long period after surgery.

Low-intensity Extracorporeal Shockwave Therapy for the Management of Postprostatectomy Erectile Dysfunction: A Systematic Review of the Literature

Context

Erectile dysfunction (ED) following radical prostatectomy is a concern for patients and their partners. Low-intensity extracorporeal shockwave therapy (LI-ESWT) can potentially enhance tissue repair and regeneration. The aim of the current study was to systematically review the literature to assess the role of LI-ESWT in the management of patients with postprostatectomy ED.

Evidence acquisition

Two authors independently performed a systematic search of the PubMed and Web of Science databases to identify all relevant articles. Non-English reports, case reports, reviews, letters, and editorials were excluded. Risk of bias was assessed according to the GRADE guidelines.

Evidence synthesis

Nine articles met the inclusion criteria and were included in the qualitative analysis. All the studies included were published between 2015 and 2022 and the majority of them compared phosphodiesterase type 5 inhibitors (PDE5Is) alone versus a combination of LI-ESWT and PDE5Is. Only three studies were randomized controlled trials (RCTs). In general, there is no standardized protocol for LI-ESWT for postprostatectomy ED. In comparisons of LI-ESWT + PDE5Is versus PDE5Is alone, some authors found a statistically significant improvement in erectile function with LI-ESWT + PDE5Is. The starting time for LI-ESWT differed among the studies, ranging from 3 d to 6 mo after surgery. The main limitations of the review are the scarcity of studies, small sample sizes, high risk of bias, and high heterogeneity among studies.

Conclusions

There is currently limited evidence on the use of LI-ESWT either alone or in combination with PDE5Is in penile rehabilitation protocols after prostatectomy. However, small clinical trials with short follow-up show that LI-ESWT could potentially play a role in the management of postprostatectomy ED in the future. Further RCTs with larger sample sizes are needed.

Patient summary

Despite limited reports in the literature, low-intensity shockwave therapy after removal of the prostate is a promising noninvasive treatment for dealing with erectile dysfunction after surgery.

Microenergy acoustic pulses promotes muscle regeneration through in situ activation of muscle stem cells

Microenergy acoustic pulses (MAP) is a modified low-intensity extracorporeal shock wave therapy that currently used for treating musculoskeletal disorders. However, its function on muscle regeneration after ischemia-reperfusion injury (IRI) remains unknown. This study aimed to explore the effect of MAP on muscle injury after IRI and its underlying mechanisms. Ten-week-old C57BL/6J mice underwent unilateral hindlimb IRI followed with or without MAP treatment. Wet weight of tibialis anterior muscles at both injury and contralateral sides were measured followed with histology analysis at 3 weeks after IRI. In in vitro study, the myoblasts, endothelial cells and fibro-adipogenic progenitors (FAP) were treated with MAP. Cell proliferation and differentiation were assessed, and related gene expressions were measured by real-time PCR. Our results showed that MAP significantly increased the muscle weight and centrally nucleated regenerating muscle fiber size along with a trend in activating satellite cells. In vitro data indicated that MAP promoted myoblast proliferation and differentiation and endothelial cells migration. MAP also induced FAP brown/beige adipogenesis, a promyogenic phenotype of FAPs. Our findings demonstrate the beneficial function of MAP in promoting muscle regeneration after IR injury by inducing muscle stem cells proliferation and differentiation.

The Efficacy of Li-ESWT Combined With VED in Diabetic ED Patients Unresponsive to PDE5is: A Single-Center, Randomized Clinical Trial

INTRODUCTION

Phosphodiesterase type 5-inhibitors (PDE5is) are the first-line treatment for patients with diabetes mellitus-induced erectile dysfunction (DMED), however, some patients are non-responser to PDE5is. We performed a perspective, randomized, comparative study to explore the efficacy of low intensity extracorporeal shock wave treatment (Li-ESWT) combined with vacuum erectile device (VED) in the treatment of DMED patients who were unresponsive to PDE5is.

METHODS

One hundred and five eligible patients were randomly divided into three groups: group A (VED), group B (Li-ESWT) and group C (VED plus Li-ESWT). Follow-up was conducted at 4 weeks, 8 weeks and 12 weeks after the end of treatment. The erectile function was estimated by the international index of erectile function-erectile function domain (IIEF-EF), erection hardness score (EHS), sexual encounter profile questions 2 and 3 (SEP2 and SEP3) and global assessment question 1 and 2 (GAQ1 and GAQ2) before and after treatment. The changes of five points in IIEF-EF were calculated as the minimal clinical important difference (MCID), which was considered as the main index of efficacy.

RESULTS

The MCID was achieved in 14.7%, 14.7% and 17.6% patients in group A at the follow up on 4 weeks, 8 weeks and 12 weeks, respectively (36.4%, 39.4% and 36.4% in group B; 36.4%, 51.5%, and 66.7% in group C). There were significant differences in the percentage of MCID cases between group A and group C at the follow up on 12 weeks (P<0.001), as well as that between group B and group C (P=0.014). Additionally, comparison in MCID within group C showed that there were significant differences between 4 weeks and 12 weeks follow-up (P=0.014).

CONCLUSION

Our findings indicated the combined therapy Li-ESWT and VED was more beneficial to shift turn PDE5is non-responders to responders for moderate patients with DMED than VED or Li-ESWT monotherapy. Moreover, this study provided evidence that patients with DMED who failed after taking oral PDE5is could attempt to opt for an alternative physicotherapy (Li-ESWT or VED) prior to more invasive alternatives.

[Shock wave therapy in oncology: in vitro, in vivo, rehabilitation]

Extracorporeal shock wave therapy (ESWT) is a relatively new branch of physiotherapy.

PURPOSE OF THE STUDY

Conduct an analytical review of the available literature data on the use of ESWT in oncology.

MATERIAL AND METHODS

A review was conducted, including data from electronic databases: Scopus, Web of Science, MedLine, World Health Organization, The Cochrane Central Register of Controlled Trials, ScienceDirect, US National Library of Medicine National Institutes of Health, PubMed, Google Scholar, elibrary, CyberLeninka, disserCat.

RESULTS AND CONCLUSION

The study of ESWT in oncology is carried out in two directions: 1) impact on the tumor with the aim of its disintegration, inhibition of growth, enhancement of the action of radiation and/or chemotherapy; 2) rehabilitation of cancer patients. Shock waves in vitro and in vivo significantly reduce the viability and activate apoptosis of cell lines of osteosarcoma, cancer of the stomach, colon, rectum, bladder, breast, urothelial cancer of the upper urinary tract, adenocarcinoma of the cervix, Burkitt's lymphoma, sarcoma, anaplastic thyroid cancer glands, glioblastoma multiforme. Shock waves also sensitize tumor cells for adjuvant chemotherapy and increase its antitumor activity. The lack of a stimulating effect on a number of malignant tumors in this physical factor makes it possible to conduct ESWT studies in the rehabilitation of cancer patients. The data obtained by a number of authors indicate the clinical efficacy of ESWT in the rehabilitation of patients with erectile dysfunction after radical prostatectomy, with postmastectomy lymphedema of the upper limb, with myofascial pain syndrome after cervical lymph node dissection due to malignant neoplasms of the head and neck, with peripheral polyneuropathy induced by cytostatics. However, in order to develop indications and contraindications for the appointment of ESWT in the rehabilitation of cancer patients, it is not enough just to evaluate its clinical effectiveness; currently absent scientific studies with long-term follow-up of patients who received this method of physiotherapy are needed.

Penile rehabilitation with low-intensity extracorporeal shock wave therapy in patients after prostate cancer surgery. Early physiological changes and postoperative follow-up outcomes

INTRODUCTION

To investigate the efficacy, safety and postoperative outcomes of using tadalafil and low-intensity extracorporeal shock wave therapy (Li-ESWT) on penile rehabilitation and preventing urinary incontinence after radical prostatectomy.

METHODS

In total, we included 66 patients who used only tadalafil (n = 32) in group 1 and used tadalafil and treated by Li-ESWT (n = 34) in group 2. We noted International Index of Erectile Function (IIEF) 5, daily incontinence pad measurements at preoperative, postoperative 3rd, 6th and 12th months respectively. We also evaluated penis blood flow and neovascularisation by penile doppler ultrasonography at postoperative 3rd and 12th months for all patients. Statistical analyses were performed with SPSS version 18. A P-value < .05 was considered significant.

RESULTS

Preoperative demographic characteristics were similar in the two groups. There was a statistically significant improvement in IIEF-5, which started at the 6th month and continued increasingly at the 12th month in group 2 compared with group 1. Also, there was a significant decrease in incontinence rate in group 2 compared with group 1 in the sixth month.

CONCLUSIONS

Combined use of tadalafil and Li-ESWT is highly effective and safe for the treatment of erectile dysfunction and for the prevention of urinary incontinence after prostate cancer surgery.

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

Regenerative technology to restore and preserve erectile function in men following prostate cancer treatment: evidence for penile rehabilitation in the context of prostate cancer survivorship

Introduction

Erectile dysfunction (ED) following prostate cancer treatment is not uncommon and penile rehabilitation is considered the standard of care in prostate cancer survivorship (PCS), where both patient and his partner desire to maintain and/or recover pre-treatment erectile function (EF). There is a clinical interest in the role of regenerative therapy to restore EF, since existing ED treatments do not always achieve adequate results.

Aim

To review regenerative therapies for the treatment of ED in the context of PCS.

Materials and Methods

A review of the existing PubMed literature on low-intensity extracorporeal shockwave therapy (LIESWT), stem cell therapy (SCT), platelet-rich plasma (PRP), gene therapy, and nerve graft/neurorrhaphy in the treatment of ED and penile rehabilitation, was undertaken.

Results

IESWT promotes neovascularization and neuroprotection in men with ED. While several systematic reviews and meta-analyses showed positive benefits, there is limited published clinical data in men following radical prostatectomy. Cellular-based technology such as SCT and PRP promotes cellular proliferation and the secretion of various growth factors to repair damaged tissues, especially in preclinical studies. However, longer-term clinical outcomes and concerns regarding bioethical and regulatory frameworks need to be addressed. Data on gene therapy in post-prostatectomy ED men are lacking; further clinical studies are required to investigate the optimal use of growth factors and the safest vector delivery system. Conceptually interpositional cavernous nerve grafting and penile re-innervation technique using a somatic-to-autonomic neurorrhaphy are attractive, but issues relating to surgical technique and potential for neural 'regeneration' are questionable.

Conclusion

In contrast to the existing treatment regime, regenerative ED technology aspires to promote endothelial revascularization and neuro-regeneration. Nevertheless, there remain considerable issues related to these regenerative technologies and techniques, with limited data on longer-term efficacy and safety records. Further research is necessary to define the role of these alternative therapies in the treatment of ED in the context of penile rehabilitation and PCS.

X-ray micro-computed tomography in the assessment of penile cavernous fibrosis in a rabbit castration model

BACKGROUND

Current assessment methods of penile cavernous fibrosis in animal models have limitations due to the inability to provide complex and volume analysis of fibrotic alterations.

OBJECTIVE

The aim was to evaluate micro-computed tomography (micro-CT) for assessment of cavernous fibrosis and compare it with histological, histochemical, immunohistochemical, and RT-PCR analysis.

MATERIALS AND METHODS

A controlled trial was performed involving 25 New Zealand male rabbits with induced testosterone deficiency by orchidectomy. Penile samples were obtained before and after 7, 14, 21, 84 days from orchidectomy. We consistently performed: a) gray value analysis of corpora cavernosa 3D models reconstructed after micro-CT; b) morphometry of smooth muscles/connective tissue ratio, collagen type I/III ratio, and area of TGF-beta-1 expression in corpora cavernosa; c) RT-PCR of TGF-beta-1 expression.

RESULTS

Micro-CT allowed visualization of penile structures at the resolution comparable to light microscopy. Gray values of corpora cavernosa decreased from 1673 (1512-1773) on the initial day to 1184 (1089-1232) on 21 day (p < 0,005); however, on 84 day, it increased to 1610 (1551-1768). At 21 and 84 days, there were observed a significant decrease in smooth muscle/connective tissue ratio and a significant increase in collagen type I/III ratio (p < 0,05). TGF-beta1 expression increased on 84 day according to immunohistochemistry (p < 0,005). RT-PCR was impossible to conduct due to the absence of RNA in obtained samples after micro-CT.

DISCUSSION AND CONCLUSIONS

Micro-CT provided 3D visualization of entire corpora cavernosa and assessment of radiodensity alterations by gray value analysis in fibrosis progression. We speculate that gray value changes at early and late fibrosis stages could be related to tissue reorganization. RT-PCR is impossible to conduct on tissue samples studied by micro-CT due to RNA destruction. We also suggest that micro-CT could negatively affect the immunohistochemical outcome, as a significant increase of TGF-beta-1 expression occurs later than histological fibrotic signs. This article is protected by copyright. All rights reserved.

Low-intensity extracorporeal shock wave therapy for male chronic pelvic pain syndrome: a systematic review and meta-analysis

Background

A systematic review of the evidence was conducted to evaluate the efficacy of low-intensity extracorporeal shock wave therapy (LI-ESWT) for patients with chronic pelvic pain syndrome (CPPS).

Methods

A comprehensive search was undertaken of the Cochrane Register, PubMed, and Embase databases for controlled trials that evaluated patients with CPPS who were treated with LI-ESWT and that were published before August 2019. The National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) was the most frequently used tool to evaluate the treatment efficacy of LI-ESWT. The NIH-CPSI comprises subscales for pain [using a visual analog scale (VAS)], urinary function, and quality of life (QoL).

Results

Six studies analyzing 317 patients were published from 2009 to 2019. The overall meta-analysis of the data indicated that LI-ESWT demonstrated efficacy in the treatment of CPPS at 12 weeks [risk difference (RD): 0.46; 95% confidence interval (CI), 0.28–0.63; P<0.00001]. The studies were divided into 3 groups based on time after LI-ESWT (1, 12, and 24 weeks) and were compared in total NIH-CPSI scores, QoL, VAS scores, and urinary symptoms. The total NIH-CPSI scores, QoL, VAS scores, and urinary symptom scores improved significantly at 12 weeks after LI-ESWT (P<0.05), but not at 1 week or 24 weeks (P>0.05).

Conclusions

Based on these studies, LI-ESWT may transiently improve the total NIH-CPSI scores, QoL, pain scores, and urinary symptom scores of patients with CPPS. Future research may elucidate the mechanisms underlying the effects of LI-ESWT on CPPS. Well-designed and long-term multicenter randomized controlled trials are urgently needed to estimate the real potential and ultimate use of these devices in patients with CPPS.

Reviewing the evidence for shockwave- and cell-based regenerative therapies in the treatment of erectile dysfunction

Erectile dysfunction (ED) is both a common and complex disease process. Existing ED treatments do not always achieve adequate results. There is clinical interest in employing regenerative therapies, including low-intensity extracorporeal shockwave therapy (Li-ESWT), platelet rich plasma (PRP), and stem cell therapy (SCT), in the treatment of ED as adjunct or alternative treatments. Here, we present evidence for emerging shockwave- and cell-based regenerative therapies for the treatment of ED following a thorough review of the existing PubMed literature pertaining to Li-ESWT, PRP, and SCT in relation to the treatment of ED. Li-ESWT causes microtrauma in tissue that hypothetically upregulates angiogenesis and recruits stem cells. Several large-scale systematic reviews and meta-analyses have reported that Li-ESWT improved ED in humans. Additionally, evidence has commenced to show that Li-ESWT may be effective against two recognized and complex etiologies of ED: diabetic and neurogenic. PRP delivers an autologous sample rich in growth factors to damaged tissue. Animal model studies have demonstrated improved erectile function recovery as well as preservation of cavernous nerve axons. Studies with PRP in humans are limited. SCT utilizes the regenerative potential of stem cells for healing of damaged tissue. In the treatment of ED, SCT has been used in the setting of diabetic and post-prostatectomy ED. Results of human studies are varied, although SCT treatments did result in increased erectile rigidity with some patients recovering the ability to achieve penetration. While these regenerative therapies show potential to augment the current treatment regimen for ED, there is a paucity of evidence to support the safety and efficacy of these treatments. Further research is necessary to define the role of these alternative therapies in the treatment of ED.

Effect of penile rehabilitation with low intensity extracorporeal shock wave therapy on erectile function recovery following robot-assisted laparoscopic prostatectomy

BACKGROUNDS

Considering the natural course of cavernous nerve recovery after robot-assisted laparoscopic prostatectomy (RALP), early intervention of low intensity extracorporeal shock wave therapy (LIESWT) would be more effective for enhancing overall recovery of sexual function (SF). Our objective of this study is to analyze longitudinally the alterations of SF in patients after RALP, with a focus on the effect of early and delayed intervention with LIESWT.

METHODS

A total of 5 and 11 patients underwent early and delayed intervention with LIESWT, respectively. SF was assessed with the Expanded Prostate Cancer Index Composite (EPIC). The same surgeon performed RALP on 178 patients, and these patients were assigned to the non-LIESWT group to establish a control group. The SF score of EPIC was investigated longitudinally before RALP and 3, 6, 9, and 12 months after RALP.

RESULTS

Our results show that penile rehabilitation with LIESWT immediately before urethral catheter removal improved SF scores. In the baseline, the SF score was significantly higher in the early LIESWT group (P=0.0001). The SF score was significantly lower at postoperative 6 months (early 19.2, delayed 17.9, and non-LIESWT 8.1; P=0.0171), 9 months (20.9, 25.8, and 10.2; P=0.0188), and 12 months (28.0, 21.3, and 9.5; P=0.0051) in the non-LIESWT group. We regret that there was no significant difference in the recovery of SF between the early and delayed protocol with LIESWT at all points. In keeping with our results, LIESWT demonstrated the potential to be efficacious in treatment options for severe post-radical prostatectomy (RP) erectile dysfunction (ED) as it may indirectly support its promotion of nerve regeneration in severe ED due to RP.

CONCLUSIONS

This is the first study in which LIESWT has been shown to deliver a clinical benefit on its early or delayed intervention to patients after RALP to penile rehabilitation in terms of restoring SF. Our preliminary results suggest that LIESWT could be used as a treatment option in penile rehabilitation.

Effect of penile rehabilitation with low intensity extracorporeal shock wave therapy on erectile function recovery following robot-assisted laparoscopic prostatectomy

Backgrounds

Considering the natural course of cavernous nerve recovery after robot-assisted laparoscopic prostatectomy (RALP), early intervention of low intensity extracorporeal shock wave therapy (LIESWT) would be more effective for enhancing overall recovery of sexual function (SF). Our objective of this study is to analyze longitudinally the alterations of SF in patients after RALP, with a focus on the effect of early and delayed intervention with LIESWT.

Methods

A total of 5 and 11 patients underwent early and delayed intervention with LIESWT, respectively. SF was assessed with the Expanded Prostate Cancer Index Composite (EPIC). The same surgeon performed RALP on 178 patients, and these patients were assigned to the non-LIESWT group to establish a control group. The SF score of EPIC was investigated longitudinally before RALP and 3, 6, 9, and 12 months after RALP.

Results

Our results show that penile rehabilitation with LIESWT immediately before urethral catheter removal improved SF scores. In the baseline, the SF score was significantly higher in the early LIESWT group (P=0.0001). The SF score was significantly lower at postoperative 6 months (early 19.2, delayed 17.9, and non-LIESWT 8.1; P=0.0171), 9 months (20.9, 25.8, and 10.2; P=0.0188), and 12 months (28.0, 21.3, and 9.5; P=0.0051) in the non-LIESWT group. We regret that there was no significant difference in the recovery of SF between the early and delayed protocol with LIESWT at all points. In keeping with our results, LIESWT demonstrated the potential to be efficacious in treatment options for severe post-radical prostatectomy (RP) erectile dysfunction (ED) as it may indirectly support its promotion of nerve regeneration in severe ED due to RP.

Conclusions

This is the first study in which LIESWT has been shown to deliver a clinical benefit on its early or delayed intervention to patients after RALP to penile rehabilitation in terms of restoring SF. Our preliminary results suggest that LIESWT could be used as a treatment option in penile rehabilitation.

Exosome Released From Schwann Cells May Be Involved in Microenergy Acoustic Pulse-Associated Cavernous Nerve Regeneration

BACKGROUND

Neurogenic erectile dysfunction (ED) is often refractory to treatment because of insufficient functional nerve recovery after injury or insult. Noninvasive mechano-biological intervention, such as microenergy acoustic pulse (MAP), low-intensity pulsed ultrasound, and low-intensity extracorporeal shockwave treatment, is an optimal approach to stimulate nerve regeneration.

AIM

To establish a new model in vitro to simulate nerve injury in neurogenic ED and to explore the mechanisms of MAP in vitro.

METHODS

Sprague-Dawley rats were used to isolate Schwann cells (SCs), major pelvic ganglion (MPG), and cavernous nerve with MPG (CN/MPG). SCs were then treated with MAP (0.033 mJ/mm², 1 Hz, 100 pulses), and SC exosomes were isolated. The MPG and CN/MPG were treated with MAP (0.033 mJ/mm², 1 Hz) at different dosages (25, 50, 100, 200, or 300 pulses) or exosomes derived from MAP-treated SCs in vitro.

OUTCOMES

Neurite growth from the MPG fragments and CN was photographed and measured. Expression of neurotropic factors (brain-derived neurotrophic factor, nerve growth factor, and neurotrophin-3) was checked.

RESULTS

Neurite outgrowth from MPG and CN/MPG was enhanced by MAP in a dosage response manner, peaking at 100 pulses. MAP promoted SC proliferation, neurotropic factor (brain-derived neurotrophic factor, nerve growth factor, and neurotrophin-3) expression, and exosome secretion. SC-derived exosomes significantly enhanced neurite outgrowth from MPG in vitro.

CLINICAL IMPLICATIONS

MAP may have utility in the treatment of neurogenic ED by SC-derived exosomes.

STRENGTH & LIMITATIONS

We confirmed that MAP enhances penile nerve regeneration through exsomes. Limitations of this study include that our study did not explore the exact mechanisms of how MAP increases SC exosome secretion nor whether MAP modulates the content of exosomes.

CONCLUSION

This study revealed that neurite outgrowth from MPG was enhanced by MAP and by SC-derived exosomes which were isolated after MAP treatment. Our findings indicate that one mechanism by which MAP induces nerve regeneration is by stimulation of SCs to secrete exosomes. Peng D, Reed-Maldonado AB, Zhou F, et al. Exosome Released From Schwann Cells May Be Involved in Microenergy Acoustic Pulse-Associated Cavernous Nerve Regeneration. J Sex Med 2020;17:1618-1628.

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.

Low-intensity extracorporeal shockwave therapy in the treatment of erectile dysfunction following radical prostatectomy: a critical review

Low-intensity extracorporeal shockwave therapy (LI-ESWT) to the penis has recently emerged as novel therapeutic option in the treatment of erectile dysfunction (ED). Randomized-controlled studies investigating the effect of this new treatment modality revealed promising results in men with vasculogenic ED. However, the efficacy of LI-ESWT in men who develop ED following radical prostatectomy (RP) remains obscure due to the exclusion of this group in nearly all clinical trials. In this review, the authors synthesize the findings from available preclinical and clinical studies that examine the potential utility of LI-ESWT in men with post-RP ED.

Cellular signaling pathways modulated by low-intensity extracorporeal shock wave therapy

Low-intensity extracorporeal shock wave therapy (Li-ESWT) is a form of energy transfer that is of lower intensity (<0.2mJ/mm²) relative to traditional Extracorporeal Shock Wave Lithotripsy (ESWL) used for management of urinary stones. At this intensity and at appropriate dosing energy transfer is thought to induce beneficial effects in human tissues. The proposed therapeutic mechanisms of action for Li-ESWT include neovascularization, tissue regeneration, and reduction of inflammation. These effects are thought to be mediated by enhanced expression of vascular endothelial growth factor, endothelial nitric oxide synthase, and proliferating cell nuclear antigen. Upregulation of chemoattractant factors and recruitment/activation of stem/progenitor cells may also play a role. Li-ESWT has been studied for management of musculoskeletal disease, ischemic cardiovascular disorders, Peyronie's Disease, and more recently erectile dysfunction (ED). The underlying mechanism of Li-ESWT for treatment of ED is incompletely understood. We summarize the current evidence basis by which Li-ESWT is thought to enhance penile hemodynamics with an intention of outlining the fundamental mechanisms by which this therapy may help manage ED.