Penile rehabilitation after radical prostatectomy: what the evidence really says

Global research trends on the links between prostate cancer and erectile dysfunction between 2003 and 2023: A bibliometrics and visualized study

Background

The incidence of prostate cancer (PC) has increased in recent years. Erectile dysfunction (ED) after prostate cancer treatment has aroused extensive attention. Bibliometric analysis was designed to investigate a systematic understanding of developments between PC and ED during the past 20 years.

Methods

Literatures on PC and ED were retrieved from the Web of Science Core Collection database (WoSCC). By using the VOS viewer and CiteSpace software to analysis the metrics of bibliometric literature, such as number of articles, journals, countries, institutions, authors, keywords and associated information. The number of publications per year was statistically analysed and plotted thorough Microsoft Office. In addition, Pajek software was used to adjust the visual map.

Results

A total of 2332 screened articles were included in the analysis. The Journal of Sexual Medicine, ranking first among the analysed journals, published 235 articles. The United States and Canada were leaders in PC and ED research. There is a need to strengthen inter-agency cooperation in this area of research on a global scale. Mulhall JP, as the most prolific author in this area of research, published 80 articles. And Rosen RC was the author with the most co-citated (693 co-citated). The main research focus on the prevention, treatment and management of ED after PC treatment in this field through the keyword analysis.

Conclusions

Research on PC and ED is expected to expand further worldwide. We found ED, as new sustainable treatment modalities, scientific postoperative management and psychological interventions for patients, may become the research hotspots and should be closely concerned in this study.

Dual Strategy with Adipose-Derived Stem Cells and l-arginine Recovered Cavernosal Functions in a Rat Model of Radical Prostatectomy

As standard therapy for prostate cancer, radical prostatectomy causes cavernous nerve (CN) injury and increases fibrosis and hypoxia-induced penile structural alterations. This study aimed to determine the potential beneficial effects of adipose-derived stem cells (ADSCs) and l-arginine alone or in combination on the penile erection in a rat model of erectile dysfunction caused by bilateral cavernous nerve transection (CNT). Male rats (n = 35) were randomized into five groups: Sham-operated; CNT (4-weeks); CNT plus ADSCs (1 × 106 cells by intracavernosal injection); CNT plus l-arginine (4 weeks, 10 mg/kg/day, oral); and ADSCs combined with l-arginine in CNT. In vivo erectile responses and in vitro relaxant responses were measured. Western blot and immunohistochemistry analyses were used to determine the expression and localization of endothelial nitric oxide synthase, neuronal nitric oxide synthase, transforming growth factor-beta 1, hypoxia-inducible factor-1 alpha (HIF-1α), and apoptosis markers (Bax and Bcl-2). The ratio of smooth muscle to collagen and nerve regeneration were calculated using Masson's trichrome and nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase staining. The combined treatment restored diminished erectile responses, endothelium-dependent acetylcholine, and electrical field stimulation-induced relaxation of the corpus cavernosum in rats with CNT, whereas either monotherapy produced only partial improvements. All treatment regimens restored increases in the protein expression of HIF-1 and Bax in rats with CNT. The decrease in smooth muscle mass and NADPH-diaphorase-positive nerve fibers was partially ameliorated by monotherapy, whereas combined therapy led to recovery. These findings indicate that combined treatment with ADSCs and l-arginine may restore erectile function in rats with CNT by inhibiting hypoxia-induced neurotoxicity and preserving endothelium function and smooth muscle content.

The Cavernous Nerve Injury Rat Model: A Pictorial Essay on Post-Radical Prostatectomy Erectile Dysfunction Research

Understanding and addressing post-radical prostatectomy (RP) erectile dysfunction (ED) is of paramount importance for clinicians. Cavernous nerve (CN) injury rat model studies have provided consistently promising experimental data regarding regaining erectile function (EF) after nerve damage-induced ED. However, these findings have failed to translate efficiently into clinical practice, with post-RP ED therapeutic management remaining cumbersome and enigmatic. This disparity highlights the need for further standardization and optimization of the elaborate surgical preparation protocols and multifaceted reporting parameters involved in reliable CN injury rat model experimentation. Even so, despite its technical complexity, this animal model remains instrumental in exploring the functional implications of RP, i.e., surgical lesions of the neurovascular bundles (NVBs). Herein, besides cavernous nerve (CN) dissection, injury, and electrostimulation, multiple pressure measurements, i.e., mean arterial pressure (MAP) and intra-cavernosal pressure (ICP), must also be achieved. A transverse cervical incision allows for carotid artery cannulation and MAP measurements. Conversely, ICP measurements entail circumcising the penis, exposing the ischiocavernous muscle, and inserting a needle into the corporal body. Finally, using an abdominal incision, the prostate is revealed, and the major pelvic ganglia (MPG) and CNs are dissected bilaterally. Specific surgical techniques are used to induce CN injuries. Herein, we provide a narrative and illustrative overview regarding these complex experimental procedures and their particular requirements, reflecting on current evidence and future research perspectives.

Dimethyl fumarate ameliorates erectile dysfunction in bilateral cavernous nerve injury rats by inhibiting oxidative stress and NLRP3 inflammasome-mediated pyroptosis of nerve via activation of Nrf2/HO-1 signaling pathway

OBJECTIVE

To investigate the therapeutic potential of dimethyl fumarate (DMF) in improving erectile function of bilateral cavernous nerve injury (BCNI) rats, along with elucidating its underlying mechanisms.

METHODS

A BCNI rat model was established by clamping bilateral cavernous nerve (CN). DMF was given by gavage at low (20 mg/kg/day) and high (40 mg/kg/day) dosages for a duration of 4 weeks. Erectile function was assessed by electrical stimulation of CN. Penis and CN tissues were collected for subsequent analysis. Additionally, PC-12 cell line was used to verify the mechanism of DMF in vitro. Nfe2l2 or Ho-1 gene knockdown PC-12 cell lines were constructed by lentiviral transfection, respectively. A damaged cell model was induced using H2O2. And then molecular biological methods were employed to analyze cellular molecules and proteins.

RESULTS

DMF administration for 4 weeks led to improvements in erectile function, reduced fibrosis of penis corpus cavernosum in BCNI rats. The morphology of CN was improved and the number of nerve fibers increased. Furthermore, the levels of nNOS, NO, and cGMP were increased, while Ca2+ was decreased in penis corpus cavernosum. Notably, the levels of ROS, 3-NT and NLRP3 inflammasomes production were reduced, alongside increased expression of Nrf2 and HO-1 proteins in the dorsal penile nerve (DPN) and CN. In vitro, DMF increased cell viability, reduced ROS level, promoted SOD, diminished 3-NT, MDA and DNA damage markers, and inhibited the activation of NLRP3 inflammasomes in H2O2 induced PC-12 cells. Nfe2l2 knockdown and Ho-1 knockdown significantly attenuated the protective effect of DMF, respectively. Furthermore, inhibition of ROS production by N-acetylcysteine led to a reduction in NLRP3 inflammasome activation in H2O2 induced PC-12 cells.

CONCLUSIONS

DMF improved erectile function of BCNI rats by protecting nerves through inhibiting oxidative stress and the activation of NLRP3 inflammasome-mediated pyroptosis via activation of Nrf2/HO-1 pathway.

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.

Restoring Quality of Life: A Comprehensive Review of Penile Rehabilitation Techniques Following Prostate Surgery

Prostate cancer is the most common type of cancer in men, and its treatment options include surgery, radiation therapy, and chemotherapy. Prostate surgery can often result in erectile dysfunction (ED), significantly impacting patients' quality of life. Penile rehabilitation techniques have been developed to restore erectile function following prostate surgery. This review discusses the different penile rehabilitation techniques available, their effectiveness, and the factors affecting their success. This paper also addresses the importance of addressing the psychological aspects of ED in these patients and the need for personalized and tailored rehabilitation plans. By providing a comprehensive understanding of penile rehabilitation techniques, this paper can assist clinicians in restoring the quality of life of patients who have undergone prostate surgery.

Overexpression of PRDX2 in Adipose-Derived Mesenchymal Stem Cells Enhances the Therapeutic Effect in a Neurogenic Erectile Dysfunction Rat Model by Inhibiting Ferroptosis

Neurogenic erectile dysfunction (NED) is a common and serious complication after pelvic surgery. The clinical translation of adipose-derived mesenchymal stem cell (ADSC) therapies in NED remains a major challenge due to their low survival rate and limited therapeutic effect. Peroxiredoxin 2 (PRDX2) is a member of the peroxidase family that exerts its therapeutic effects by inhibiting oxidative stress (OS) and ferroptosis, and PRDX2 is expected to enhance the therapeutic effect of ADSCs in treating NED. The purpose of this study was to investigate whether PRDX2 could improve the survival of ADSCs and determine whether overexpression of PRDX2 in ADSCs (PRDX2-ADSCs) could enhance the therapeutic effect of NED. This study investigated the potential role of PRDX2-ADSCs through a NED model induced by bilateral cavernous nerve injury (BCNI) and three in vitro models established by H₂O₂-stimulated ADSCs, H₂O₂-stimulated corpus cavernosum smooth muscle cells (CCSMCs), and RSL3-stimulated CCSMCs. We found that PRDX2 could significantly improve the viability of ADSCs by suppressing apoptosis and OS in H₂O₂-stimulated ADSCs. We also found that BCNI triggered ferroptosis of the corpus cavernosum, which was manifested by increased reactive oxygen species (ROS), total iron content, and MDA as well as decreased SOD and GSH. Our results further demonstrated changes in the expression of key proteins (GPX4 and ACSL4) in the ferroptosis pathway, whereas PRDX2-ADSCs ameliorated BCNI-induced erectile dysfunction and ferroptosis of the corpus cavernosum in NED rats. Consistently, PRDX2-ADSCs attenuated OS in H₂O₂-stimulated CCSMCs and inhibited ferroptosis in RSL3-stimulated CCSMCs, as evidenced by the decrease in ROS, total iron content, and MDA and the increase in SOD and GSH together with changes in ferroptosis-related protein (GPX4 and ACSL4) expression. In conclusion, overexpression of PRDX2 in ADSCs enhanced the therapeutic effect in a rat model of neurogenic erectile dysfunction by inhibiting ferroptosis via regulation of the GPX4/ACSL4 axis.

Long-term consequences of bilateral cavernous crush injury in normal and diabetic rats: a functional study

A recent statement from the European-Society-for-Sexual-Medicine has highlighted the limitations of using the rat model for nerve-sparing prostatectomy. The use of young rats with no comorbidities and the early evaluation of the erectile function (EF) are deemed a source of bias. Our aim was to evaluate the long-term consequences in EF of bilateral nerve cavernous crush- injury (BNCI) in type 1 diabetic (DM) rats 30-male/12-week-old rats were divided into four groups: Sham, BNCI, DM, and BNCI + DM. Sham group underwent an intraperitoneal injection (IP) of saline solution and after 1 month underwent a sham laparotomy. BNCI underwent an IP of saline solution and after 1 month to BNCI. DM underwent an IP of 60 mg/kg-1-streptozotocin (STZ) and after 1 month to a sham laparotomy. BNCI + DM underwent an IP of 60 mg/kg-1-STZ and after 1 month to BNCI. After 5 months from the induction of diabetes, all rats underwent measurement of intracorporeal pressure (ICP) and mean arterial pressure (MAP) during CN-electrostimulation. Multiple groups were compared using Kruskal-Wallis one-way analysis of variance followed by Mann-Whitney U test for post hoc comparisons. Blood glucose-level was higher (p < 0.05) in the groups with DM and BNCI + DM. After 5-months, DM and BNCI + DM also showed a lower weight compared to other groups (p < 0.05). No differences were noted in ICP/MAP between the sham and BNCI. BNCI + DM showed lower ICP/MAP compared to all the groups (p < 0.05). DM Showed lower ICP/MAP compared to Sham and BNCI (p < 0.05). BNCI in rats without comorbidities did not induce long-term erectile dysfunction (ED) suggesting a spontaneous EF recovery. BNCI in DM induced long-term ED. The results of previous short-term studies can only provide evidence on the time to recovery of spontaneous EF as to the actual EF recovery rate.

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.

Acetyl-L-carnitine improves erectile function in bilateral cavernous nerve injury rats via promoting cavernous nerve regeneration

BACKGROUND

Neurogenic erectile dysfunction (NED) caused by cavernous nerve (CN) injury is a typical complication after pelvic surgery, which lacks efficient treatments. Acetyl-L-carnitine (ALCAR) has been proven to promote nerve repair.

OBJECTIVES

To investigate the effect and potential mechanism of ALCAR in the treatment of NED.

MATERIALS AND METHODS

Thirty-two rats were randomly divided into bilateral cavernous nerve injury (BCNI) group, BCNI + lower-dose ALCAR (50 mg/kg/day) group, BCNI + higher-dose (100 mg/kg/day) group and sham-operated group. Erectile function was assessed 14 days after daily intraperitoneal injection of ALCAR or placebo. The penile tissues were gathered for subsequent histological and molecular biological analysis. Rat Schwann cell (SC) line S16 was used to verify the mechanism of ALCAR in vitro.

RESULTS

We found that the erectile function of the rats in BCNI group was severely impaired, which was improved considerably in both BCNI+ALCAR-LD and BCNI+ALCAR-HD groups. Also, we observed decreased smooth muscle and increased collagen content in corpus cavernosum in BCNI group. The expressions of fibrosis markers TGF-β, CTGF, and Smad 2/3 were significantly up-regulated in the BCNI group. The above changes were alleviated after the administration of lower and higher-dose ALCAR. Meanwhile, the NO/cGMP pathway was promoted and the RhoA/ROCK pathway was inhibited in the corpus cavernosum of BCNI rats after ALCAR treatment, accompanied by increased nNOS and down-regulated Tyrosine Hydroxylase. In vitro, ALCAR promoted the migration and proliferation of SC, and increased the expression of Pmp22 and NGF. Further, rats treated with ALCAR had high expression of ATF3 and S100 in the distal nerve tissues of the CN extrusion site.

DISCUSSION AND CONCLUSION

ALCAR could promote nerve repair and regeneration, inhibit penile fibrosis and improve penile erection by promoting the proliferation and migration of SC and the secretion of NGF. Our study confirms that ALCAR may be a potential treatment strategy for NED. This article is protected by copyright. All rights reserved.

Lipopolysaccharide-preconditioned allogeneic adipose-derived stem cells improve erectile function in a rat model of bilateral cavernous nerve injury

Background

Erectile dysfunction (ED) often occurs due to cavernous nerve injury (CNI) after colorectal surgery. Cell-based therapies have great potential for the treatment of CNI-related ED; however, it needs to be optimised. In this study, we explored the therapeutic effects of lipopolysaccharide-preconditioned allogeneic adipose-derived stem cells (L-ADSCs) on CNI-induced ED in rats.

Results

The results of this in vitro study revealed that low-dose lipopolysaccharide could increase the viability of ADSCs, inhibit caspase 3 activation induced by hydrogen peroxide and promote cell migration. Compared with the ADSC supernatant, the L-ADSC supernatant could better reduce fibrosis in the corpus cavernosum smooth muscle cells induced by transforming growth factor-beta 1 protein. In the in vivo study, it was compared to ADSCs therapy, where the L-ADSCs therapy indicated that could better improve erectile function by increasing smooth muscle content and alleviating penile fibrosis in rats 2 weeks after CNI. The outcome may be related to the increase in the hepatocyte growth factor content in the corpus cavernosum and myelin basic protein in the major pelvic ganglion.

Conclusions

L-ADSC treatment may be a promising approach for restoring erectile function after CNI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12610-022-00156-w.

Restoration of erectile function by a combination of antiapoptosis by JNK inhibitor and preservation of smooth muscle or endothelium by hepatocyte growth factor in a rat model of cavernous nerve injury

BACKGROUND

Because of structural alterations in the corpus cavernosum after radical prostatectomy (RP), post-RP erectile dysfunction remains a very difficult condition to treat. We aimed to determine if the combined administration of a Jun-amino terminal kinase (JNK) inhibitor and hepatocyte growth factor (HGF) in the immediate post-injury period would restore erectile function by antiapoptotic and pro-regenerative effects through the rectification of molecular pathways related to the structural integrity of the penis in a rat model of bilateral cavernosal nerve crush injury (CNCI).

METHODS

A total of 70 rats were divided into five groups: Sham surgery (S), CNCI (I), and once-daily intraperitoneal administration of 10.0 mg/kg JNK inhibitor + twice-weekly intracavernosal administration of low-dose (2.1 μg), medium-dose (4.2 μg), or high-dose (8.4 μg) HGF (I + J + LH or I + J + MH or I + J + HH, respectively) in the immediate post-injury period. Erectile responses to electrostimulation (1.0, 3.0, and 5.0 V), histological staining, caspase-3 activity, and Western blotting were evaluated 9 days after surgery.

RESULTS

Group I showed lower intracavernosal pressure (ICP)/mean arterial pressure (MAP) after stimulation at each voltage, lower area under the curve (AUC)/MAP after stimulation at each voltage, less smooth muscle (SM) content, a lower SM/collagen ratio, higher caspase-3 activity, increased cJun phosphorylation, decreased protein expression of PECAM-1, decreased cMet phosphorylation, and decreased endothelial nitric oxide synthase (eNOS) phosphorylation compared to Group S. The SM content, SM/collagen ratio, protein expression of ICP/MAP, or AUC/MAP after stimulation at each voltage in Group I + J + LH were partially restored, despite the normalization of cJun phosphorylation and caspase-3 activity. The ICP/MAP, AUC/MAP, caspase-3 activity, SM content, protein expression of PECAM-1, cJun phosphorylation, cMet phosphorylation, and eNOS phosphorylation in both Groups I + J + MH and I + J + HH were restored to the levels observed in Group S, while the SM/collagen ratio was significantly improved but not completely normalized.

CONCLUSIONS

Our data indicated that the combined administration of a JNK inhibitor and medium or high-dose HGF to nerve-injured rats in the immediate post-injury period after CNCI may restore erectile function to a level comparable to the normal level by suppressing cavernosal apoptosis and preserving the integrity of SM or endothelium via rectification of the cJun and cMet/eNOS pathways.

An online Sexual Health and Rehabilitation eClinic (TrueNTH SHAReClinic) for prostate cancer patients: a feasibility study

Purpose

The primary objective was to determine the feasibility of implementing the TrueNTH SHAReClinic as a pan-Canadian sexual health and rehabilitation intervention for patients treated for localized prostate cancer.

Methods

The feasibility study was designed to evaluate the accessibility and acceptability of the intervention. Participants from five institutions across Canada were enrolled to attend one pre-treatment and five follow-up online clinic visits over 1 year following their prostate cancer (PC) treatment.

Results

Sixty-five patients were enrolled in the intervention. Website analytics revealed that 71% completed the intervention in its entirety, including the educational modules, with an additional 10% completing more than half of the intervention. Five thousand eighty-three views of the educational modules were made along with 654 views of the health library items. Over 1500 messages were exchanged between participants and their sexual health coaches. At 12 months, the intervention received an overall average participant rating of 4.1 out of 5 on a single item satisfaction measure.

Conclusion

Results support the TrueNTH SHAReClinic as highly acceptable to participants as defined by intervention adherence and engagement. The TrueNTH SHAReClinic demonstrated promise for being a feasible and potentially resource-efficient approach to effectively improving the sexual well-being of patients after PC treatment.

Long noncoding RNA H19 promotes the apoptosis of corpus cavernsum smooth muscle cells after cavernosal nerve injury via JNK signalling pathway

JNK/ Bcl-2/ Bax pathway participates in corpus cavernosal smooth muscle cells apoptosis during early period after cavernosal nerve (CN) crush injury (CNCI). Nevertheless, the regulation mechanisms of long noncoding RNA H19 in apoptosis during early stage after CN injury are still poorly understood. The rats in sham group were not direct injury to the CNs. The rats in CNCI group were performed to bilateral CN crush injury. The ICP/MAP rate and smooth muscle content were significantly lower than that in the sham group. Primary CCSMCs were prepared from the tissues samples after completing erectile function detection. Phosphorylated-JNK level was increased significantly, and the expression of Bax and Bcl-2 was elevated and declined in CNCI group respectively. Except for Bcl-2, the mRNA levels of H19, JNK and Bax were significantly increased in CNCI group. After H19 siRNA transfection, for the mRNA and protein levels, JNK and Bax were declined, while Bcl-2 was enhanced. LncRNA H19 might be involved in regulation of Bcl-2, Bax via JNK signalling pathway in CCSMCs apoptosis after CN injury.

A novel flavonoid derivative of icariside II improves erectile dysfunction in a rat model of cavernous nerve injury

BACKGROUND

Icariside II (ICA II), an active flavonoid monomer, has been proven to restore post-prostatectomy erectile dysfunction in rats; however, the high cost of extraction from natural plants limits the application of ICA II.

OBJECTIVE

To investigate the therapeutic effect and possible mechanism of action of YS-10, a new flavonoid compound, which was designed and synthesized based on the structure of ICA II in a rat model in of cavernous nerve injury.

MATERIALS/METHODS

Eight of 32 adult male Sprague-Dawley rats were selected as the normal control (NC) group and received vehicle treatment. The remaining rats were subjected to bilateral cavernous nerve injury (BCNI) and randomized into three groups: BCNI group, BCNI + ICA II group (2.5 mg/kg/day), and BCNI + YS-10 group (2.5 mg/kg/day). The total procedure lasted for 21 days, followed by a washout period of 3 days. All animals were evaluated for erectile function, and tissues were harvested for histopathological analyses.

RESULTS

It was observed that in YS-10 group, the ratio of intracavernous pressure (ICP) to mean arterial pressure (MAP) and the area under the ICP/MAP curve were effectively enhanced. The maximum ICP/MAP increased by 30% in the YS-10 group (0.86 ± 0.085) compared with the BCNI group (0.66 ± 0.058), which is close to 82% of the NC group (1.05 ± 0.033). Histopathological changes demonstrated significant reduction of smooth muscle atrophy, collagen deposition, and endothelial and neural dysfunction after YS-10 treatment, which have no statistical differences compared with ICA II group. Additionally, high-protein expression levels of β-Catenin and cyclin D1 were observed in the treatment groups.

CONCLUSION

YS-10, a novel synthesized flavonoid compound, could effectively improve erectile dysfunction in rats after BCNI by alleviating pathological impairments; this effect may associate with the upregulation of β-Catenin and cyclin D1 in Wnt signaling pathway.

Prevalence of post-prostatectomy erectile dysfunction and a review of the recommended therapeutic modalities

Radical prostatectomy (RP) represents one of the most commonly used first-line treatment modalities in men with localized prostate cancer. One of the most feared post-surgical complications is erectile dysfunction (ED), usually caused by direct damage to the cavernous nerves or due to neuropraxia. Penile rehabilitation is an emerging concept that was proposed to stimulate and accelerate recovery of erectile function after RP. The goal is to improve blood flow to the penis, increasing cavernous oxygenation and avoiding fibrosis. The most common used modalities include oral phosphodiesterase type 5 inhibitors (PDE5-I), vacuum erection devices (VEDs), intracorporeal injection (ICI) therapy, medicated urethral system for erections (MUSE), and a combination of these treatments. For those patients with severe ED, ED refractory to medical therapy and/or seeking long term reliable results, the penile prosthesis implant remains an excellent alternative. We conducted a broad review of post-prostatectomy ED prevalence with different techniques and the success rates of the different therapeutic approaches.

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.

Adding a vacuum erection device to regular use of Tadalafil improves penile rehabilitation after posterior urethroplasty

This study aimed to evaluate whether adding a vacuum erection device (VED) to regular use of Tadalafil could achieve better penile rehabilitation following posterior urethroplasty for pelvic fracture-related urethral injury (PFUI). Altogether, 78 PFUI patients with erectile dysfunction (ED) after primary posterior urethroplasty were enrolled and divided into two treatment groups: VED combined with Tadalafil (Group 1, n = 36) and Tadalafil only (Group 2, n = 42). Changes in penile length, testosterone level, International Index of Erectile Function-5 (IIEF-5) questionnaire, Quality of Erection Questionnaire (QEQ), and nocturnal penile tumescence (NPT) testing were used to assess erectile function before and after 6 months of ED treatment. Results showed that the addition of VED to regular use of Tadalafil preserved more penile length statistically (0.4 ± 0.9 vs −0.8 ± 0.7 cm, P < 0.01). IIEF-5 score and QEQ score in Group 1 were higher than Group 2 (both P < 0.05). After treatment, 21/36 (58.3%) Group 1 patients and 19/42 (45.2%) Group 2 patients could complete vaginal penetration. Group 1 patients also had markedly improved testosterone levels (P = 0.01). Unexpectedly, there was no significant difference in NPT testing between two therapies. For PFUI patients with ED after posterior urethroplasty, the addition of VED to regular use of Tadalafil could significantly improve their conditions – improving erection and increasing penile length – thus increasing patient satisfaction and confidence in penile rehabilitation.

Losartan improves erectile function through suppression of corporal apoptosis and oxidative stress in rats with cavernous nerve injury

This study aimed to investigate the functional and morphological changes in the corpus cavernosum after cavernous nerve (CN) injury or neurectomy and then reveal whether treatment with the angiotensin II Type 1 receptor antagonist losartan would improve erectile function as well as its potential mechanisms. A total of 48 10-week-old Sprague-Dawley male rats, weighing 300-350 g, were randomly divided into the following four groups (n = 12 per group): sham operation (Sham) group, bilateral cavernous nerve injury (BCNI) group, losartan-treated BCNI (BCNI + Losartan) group, and bilateral cavernous neurectomy (Neurectomy) group. Losartan was administered once daily by oral gavage at a dose of 30 mg kg^-1 day^-1 for 4 weeks starting on the day of surgery. The BCNI and the Neurectomy groups exhibited decreases in erectile response and increases in apoptosis and oxidative stress, compared with the Sham group. Treatment with losartan could have a modest effect on erectile function and significantly prevent corporal apoptosis and oxidative stress. The phospho-B-cell lymphoma 2 (Bcl-2)-associated death promoter (p-Bad)/Bad and phospho-the protein kinase B (p-AKT)/AKT ratios were substantially lower, while the Bcl-2-associated X protein (Bax)/Bcl-2 ratio, nuclear factor erythroid 2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap-1), transforming growth factor-β 1 (TGF-β 1) and heme oxygenase-1 (HO-1) levels, and caspase-3 activity were higher in the BCNI and Neurectomy groups than in the Sham group. After 4 weeks of daily administration with losartan, these expression levels were remarkably attenuated compared with the BCNI group. Taken together, our results suggested that early administration of losartan after CN injury could slightly improve erectile function and significantly reduce corporal apoptosis and oxidative stress by inhibiting the Akt/Bad/Bax/caspase-3 and Nrf2/Keap-1 pathways.

European Society for Sexual Medicine Consensus Statement on the Use of the Cavernous Nerve Injury Rodent Model to Study Postradical Prostatectomy Erectile Dysfunction

INTRODUCTION

Rodent animal models are currently the most used in vivo model in translational studies looking into the pathophysiology of erectile dysfunction after nerve-sparing radical prostatectomy.

AIM

This European Society for Sexual Medicine (ESSM) statement aims to guide scientists toward utilization of the rodent model in an appropriate, timely, and proficient fashion.

METHODS

MEDLINE and EMBASE databases were searched for basic science studies, using a rodent animal model, looking into the consequence of pelvic nerve injury on erectile function.

MAIN OUTCOME MEASURES

The authors present a consensus on how to best perform experiments with this rodent model, the details of the technique, and highlight possible pitfalls.

RESULTS

Owing to the specific issue-basic science-Oxford 2011 Levels of Evidence criteria cannot be applied. However, ESSM statements on this topic will be provided in which we summarize the ESSM position on various aspects of the model such as the use of the Animal Research Reporting In Vivo Experiments guideline and the of common range parameter for nerve stimulation. We also highlighted the translational limits of the model.

CONCLUSION

The following statements were formulated as a suggestive guidance for scientists using the cavernous nerve injury model. With this, we hope to standardize and further improve the quality of research in this field. It must be noted that this model has its limitations. Weyne E, Ilg MM, Cakir OO, et al. European Society for Sexual Medicine Consensus Statement on the Use of the Cavernous Nerve Injury Rodent Model to Study Postradical Prostatectomy Erectile Dysfunction. Sex Med 2020;8:327-337.

The Combined Use of Stem Cells and Platelet Lysate Plasma for the Treatment of Erectile Dysfunction: A Pilot Study-6 Months Results

Background: The current treatment of Erectile Dysfunction (ED) is mainly based on the use of drugs that provide erections shortly after use but they do not really treat the problem. Stem cell therapy is a novel treatment with regenerative properties that can possibly treat erectile dysfunction. Methods: Five patients with erectile disease were treated with Adipose-Derived Stem Cells (ADSCs) and Platelet Lysate Plasma (PLP). ADSCs were obtained through abdominal liposuction and PLP was prepared after obtaining blood samples from peripheral veins. Erectile function was evaluated with the International Index of Erectile Function questionnaire (IIEF-5) questionnaire, penile triplex at the 1st, 3rd, 6th and 12th month post-treatment. A CT scan of the head, thorax and abdomen was done before treatment and at the 12th month. Results: IIEF-5 scores were improved in all patients at the 6th month although not in the same pattern in all patients. Peak Systolic Velocity (PSV) also improved at the 6th month in all patients but also with different patterns in each patient, while End Diastolic Velocity (EDV) was more variable. Two patients decreased the treatment they used in order to obtain erection (from Intracavernosal injections (ICI) they used PDE-5Is), two had unassisted erections and one had an initial improvement which decreased at the 6th month. There were no side effects noted. Conclusions: Stem cell therapy in combination with PLP appears to show some improvement in erectile function and has minimal side effects in the short term.

Adipose Tissue-Derived Stem Cell Therapy for Cavernous Nerve Injury-Induced Erectile Dysfunction in the Rat Model: A Systematic Review and Meta-Analysis Using Methodological Quality Assessment

Background and Objectives

Few studies were evaluated the effect of blindness on outcome in animal models, though a potential effect of blinding has been reported in clinical trials. We evaluated the effects of adipose tissue-derived stem cells (ADSCs) on cavernous nerve injury (CNI)-induced erectile dysfunction (ED) in the rat and examined how proper blinding of the outcome assessor affected treatment effect.

Methods and Results

We searched in Pubmed, EMBASE, Cochrane and Web of Science databases from inception to January 2019. We included CNI animal model, randomized controlled experiments, and ADSC intervention. Erectile function and structural changes were assessed by intracavernous pressure and mean arterial pressure (ICP/MAP) ratios, neuronal nitric oxide synthase (nNOS) levels, cavernous smooth muscle and collagen (CSM/collagen) ratios, and cyclic guanosine monophosphate (cGMP).

Results

Nineteen studies were included in the final meta-analysis. The ICP/MAP ratio of the ADSC treatment group increased compared to the control group (SMD=1.33, 95%CI: 1.11~1.56, I²=72%). The nNOS level (SMD=2.29, 95%CI: 1.74~2.84, I²=75%), CSM/collagen (SMD=2.57, 95%CI: 1.62~3.52; I²=85%), and cGMP (SMD=2.96, 95%CI: 1.82~4.10, I²=62%) were also increased in the ADSC treatment group. Preplanned subgroup analysis was conducted to explore the source of heterogeneity. Five studies with blinded outcome assessment were significantly less effective than the unblinded studies (SMD=1.33, 95%CI: 0.86~1.80; SMD=1.81, 95%CI: 1.17~2.46, respectively).

Conclusions

ADSCs might be effective in improving erectile function and structural change in CNI-induced ED. However, non-blinded outcome assessors might cause detection bias and overestimate treatment efficacy. Therefore, the ADSC efficacy must be further evaluated with a rigorous study design to avoid bias.

Role of Jun amino-terminal kinase (JNK) in apoptosis of cavernosal tissue during acute phase after cavernosal nerve injury

The present study aimed to identify which mitogen-activated protein kinase (p38 or Jun amino-terminal kinase [JNK]) was involved in cavernosal apoptosis during the acute phase after cavernosal nerve crush injury (CNCI) in rats to ameliorate apoptosis of cavernosal tissue, such as smooth muscle (SM). A total of twenty 10-week-old male Sprague-Dawley rats were divided equally into two groups: sham surgery (S) and CNCI (I). The I group approximated the clinical situation of men undergoing radical prostatectomy using two 60-second compressions of both CNs with a microsurgical vascular clamp. At 2-week postinjury, erectile response was assessed using electrostimulation. Penile tissues were harvested for immunohistochemistry analysis of alpha-SM actin (α-SMA), western blot analysis, and double immunofluorescence analysis of α-SMA and phosphorylated p38 or JNK, as well as double immunofluorescent of TUNEL and phosphorylated p38 or JNK. At 2-week postinjury, the I group had a significantly lower intracavernous pressure (ICP)/mean arterial pressure (MAP) and a lower area under the curve (AUC)/MAP than the S group. The I group also exhibited decreased immunohistochemical staining of α-SMA, an increase in the number of SM cells positive for phosphorylated JNK, an increased number of apoptotic cells positive for phosphorylated JNK, and increased JNK phosphorylation compared with the S group. However, there was no significant difference in p38 phosphorylation expression or the number of SM cells positive for phosphorylated p38 between the two groups. In conclusion, our data suggest that JNK, not p38, is involved in cavernosal apoptosis during the acute phase after partial CN damage.

Efficacy and safety of an herbal formula (KBMSI-2) in the treatment of erectile dysfunction: A preliminary clinical study

Purpose

To investigate the efficacy and safety of KBMSI-2, an herbal formula consisting of Ginseng Radix Rubra, Dioscorea tenuipes, Cornus officinalis Sieb. et Zucc., Lycium chinense Mill, and Curcuma longa Linn, for the treatment of erectile dysfunction (ED).

Materials and Methods

Patients were instructed to take placebo or 6 g of KBMSI-2 twice per day for 8 weeks, at least 1 hour after food intake. The primary outcome was a change from baseline in erectile function (EF) domain scores of the International Index of Erectile Function (IIEF) questionnaire. Secondary outcome included changes from baseline in all domain scores of the IIEF, scores on the Aging Males' Symptoms scale, and serum total testosterone levels, as well as changes in questions 2 and 3 of the Sexual Encounter Profile, responses to the Global Assessment Question, and changes in the number of ‘yes’ responses on the Androgen Deficiency in Aging Males questionnaire.

Results

Patients receiving KBMSI-2 had a statistically significant improvement in baseline IIEF-EF domain scores at 8 weeks compared to the placebo group. Intercourse satisfaction domain and the total IIEF scores also increased in the KBMSI-2 group. However, we could not find any significant differences in other efficacy variables between the groups. Only one patient had an adverse event, which was mild in severity.

Conclusions

This preliminary clinical study of KBMSI-2 shows significant improvements in EF and intercourse satisfaction, as measured by the IIEF in patients with ED. Further studies using a larger number of patients in the long term should follow.

Administration of Adipose Derived Mesenchymal Stem Cells and Platelet Lysate in Erectile Dysfunction: A Single Center Pilot Study

Erectile dysfunction (ED) affects more than 30 million men; endothelial dysfunction plays a significant role in EDs pathogenesis. The aim of this study was to administer mesenchymal stem cells (MSC) derived from adipose tissue and platelet lysate (PL) into patients with erectile dysfunction. This pilot study enrolled eight patients with diagnosed ED. Patients enrolled were suffering from organic ED due to diabetes melitus, hypertension, hypercholesterolaemia, and Peyronie disease. The patients were distributed in 2 groups. Patients in group A received adipose derived mesenchymal stem cells (ADMSC) resuspended in PL while patients in group B received only PL. ADMSCs were isolated from patients' adipose tissue and expanded. In addition, blood sampling was obtained from the patients in order to isolate platelet lysate. After the application of the above treatments, patients were evaluated with an International Index of Erectile Function (IIEF-5) questionnaire, penile triplex, and reported morning erections. After MSCs and PL administration, patients presented improved erectile function after 1 and 3 months of follow-up. A statistically significant difference was observed in the IIEF-5 score before and after administration of both treatments after the first month (p < 0.05) and the third month (p < 0.05). No statistically significant difference was observed in the IIEF-5 score between group A and B patients. All patients were characterized by improved penile triplex and increased morning erections. No severe adverse reactions were observed in any patient except a minor pain at the site of injection, which was in the limits of tolerability. The results of this study indicated the satisfactory use of MSCs and PL in ED. MSCs in combination with PL or PL alone seems to be very promising, especially without having the negative effects of the current therapeutic treatment.

The Prostate Cancer Rehabilitation Clinic: a biopsychosocial clinic for sexual dysfunction after radical prostatectomy

Purpose

The most prevalent intervention for localized prostate cancer (pca) is radical prostatectomy (rp), which has a 10-year relative survival rate of more than 90%. The improved survival rate has led to a focus on reducing the burden of treatment-related morbidity and improving the patient and partner survivorship experience. Post-rp sexual dysfunction (sdf) has received significant attention, given its substantial effect on patient and partner health-related quality of life. Accordingly, there is a need for sdf treatment to be a fundamental component of pca survivorship programming.

Methods

Most research about the treatment of post-rp sdf involves biomedical interventions for erectile dysfunction (ed). Although findings support the effectiveness of pro-erectile agents and devices, most patients discontinue use of such aids within 1 year after their rp. Because side effects of pro-erectile treatment have proved to be inadequate in explaining the gap between efficacy and ongoing use, current research focuses on a biopsychosocial perspective of ed. Unfortunately, there is a dearth of literature describing the components of a biopsychosocial program designed for the post-rp population and their partners.

Results

In this paper, we detail the development of the Prostate Cancer Rehabilitation Clinic (pcrc), which emphasizes multidisciplinary intervention teams, active participation by the partner, and a broad-spectrum medical, psychological, and interpersonal approach.

Conclusions

The goal of the pcrc is to help patients and their partners achieve optimal sexual health and couple intimacy after rp, and to help design cost-effective and beneficial rehabilitation programs.

Penile rehabilitation for postprostatectomy erectile dysfunction

BACKGROUND

Despite efforts to preserve the neurovascular bundles with nerve-sparing surgery, erectile dysfunction remains common following radical prostatectomy. Postoperative penile rehabilitation seeks to restore erectile function but results have been conflicting.

OBJECTIVES

To evaluate the effects of penile rehabilitation strategies in restoring erectile function following radical prostatectomy for prostate cancer.

SEARCH METHODS

We performed a comprehensive search of multiple databases (CENTRAL, MEDLINE, Embase), the Cochrane Library, Web of Science, clinical trial registries (ClinicalTrials.gov, International Clinical Trials Registry Platform) and a grey literature repository (Grey Literature Report) from their inception through to 3 January 2018. We also searched the reference lists of other relevant publications and abstract proceedings. We applied no language restrictions.

SELECTION CRITERIA

We included randomised or quasi-randomised trials with a parallel or cross-over design.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures. Two review authors independently screened the literature, extracted data, assessed risk of bias and rated quality of evidence according to GRADE on a per-outcome basis. Primary outcomes were self-reported potency, erectile function measured by validated questionnaires (with potency defined as an International Index of Erectile Function (IIEF-EF) score of 19 or greater and or an IIEF-5 of score of 17 or greater) and serious adverse events. For all quality of life assessments on a continuous scale, higher values indicated better quality of life.

MAIN RESULTS

We included eight randomised controlled trials with 1699 participants across three comparisons. This abstract focuses on the primary outcomes of this review only.Scheduled phosphodiesterase type 5 inhibitors (PDE5I) versus placebo or no treatmentScheduled PDE5I may have little or no effect on short-term (up to 12 months) self-reported potency (risk ratio (RR) 1.13, 95% confidence interval (CI) 0.91 to1.41; very low quality evidence), which corresponds to 47 more men with self-reported potency per 1000 (95% CI 33 fewer to 149 more) and short-term erectile function as assessed by a validated instrument (RR 1.11, 95% CI 0.80 to 1.55; very low quality evidence), which corresponds to 28 more men per 1000 (95% CI 50 fewer to 138 more), but we are very uncertain of both of these findings. Scheduled PDE5I may result in fewer serious adverse events compared to placebo (RR 0.32, 95% CI 0.11 to 0.94; low quality evidence), though this does not appear biologically plausible and may represent a chance finding. We are also very uncertain of this finding. We found no long-term (longer than 12 months) data for any of the three primary outcomes.Scheduled PDE5I versus on-demand PDE5I Daily PDE5I appears to result in little to no difference in both short-term and long-term (greater than 12 months) self-reported potency (short term: RR 0.97, 95% CI 0.62 to 1.53; long term: RR 1.00, 95% CI 0.60 to 1.67; both very low quality evidence); this corresponds to nine fewer men with self-reported short-term potency per 1000 (95% CI 119 fewer to 166 more) and zero fewer men with self-reported long-term potency per 1000 (95% CI 153 fewer to 257 more). We are very uncertain of these findings. Daily PDE5I appears to result in little to no difference in short-term and long-term erectile function (short term: RR 1.00, 95% CI 0.65 to 1.55; long term; RR 0.74, 95% CI 0.48 to 1.14; both very-low quality evidence), which corresponds to zero men with short-term erectile dysfunction per 1000 (95% CI 80 fewer to 125 more) and 119 fewer men with long-term erectile dysfunction per 1000 (95% CI 239 fewer to 64 more). We are very uncertain of these findings. Scheduled PDE5I may result in little or no effects on short-term adverse events (RR 0.69 95% CI 0.12 to 4.04; very low quality evidence), which corresponds to seven fewer men with short-term serious adverse events (95% CI 18 fewer to 64 more), but we are very uncertain of these findings. We found no long-term data for serious adverse events.Scheduled PDE5I versus scheduled intraurethral prostaglandin E1At short-term follow-up, daily PDE5I may result in little or no effect on self-reported potency (RR 1.10, 95% CI 0.79, to 1.52; very low quality evidence), which corresponds to 46 more men per 1000 (95% CI 97 fewer to 241 more). Daily PDE5I may result in a small improvement of erectile function (RR 1.64, 95% CI 0.84 to 3.20; very low quality evidence), which corresponds to 92 more men per 1000 (95% CI 23 fewer to 318 more) but we are very uncertain of both these findings. We found no long-term (longer than 12 months) data for any of the three primary outcomes.We found no evidence for any other comparisons and were unable to perform any of the preplanned subgroup analyses based on nerve-sparing approach, age or baseline erectile function.

AUTHORS' CONCLUSIONS

Based on mostly very-low and some low-quality evidence, penile rehabilitation strategies consisting of scheduled PDE5I use following radical prostatectomy may not promote self-reported potency and erectile function any more than on demand use.

Efficacy and Safety of Tadalafil 5 mg Once Daily for the Treatment of Erectile Dysfunction After Robot-Assisted Laparoscopic Radical Prostatectomy: A 2-Year Follow-Up

BACKGROUND

Although nerve-sparing robot-assisted radical prostatectomy (NS-RALP) is performed, a large number of patients still experience erectile dysfunction (ED) after surgery.

AIM

To evaluate the efficacy and safety of tadalafil 5 mg once daily (OaD) in ED treatment over 2 years and investigate the cause of vascular ED after NS-RARP.

METHODS

We retrospectively evaluated 95 men who underwent NS-RARP and had a penile rehabilitation treatment with tadalafil 5 mg OaD. They were classified into 3 groups: tadalafil 5 mg OaD for 2 years (group I), tadalafil 5 mg OaD for 1 year (group II), and no tadalafil (group III). All patients in group I underwent penile color duplex ultrasound to evaluate the cause of vascular ED.

OUTCOMES

Patients were surveyed using the abridged 5-item International Index of Erectile Function (IIEF-5).

RESULTS

Statistically significant improvements were observed in group I for all IIEF-5 domain scores (P = .000). There was no statistically significant difference in recovery of erectile function (EF) the 2-year follow-up between groups I and II. Sub-analysis based on NS status showed no difference in recovery of EF. However, group I showed better trends in EF improvement. Those with venogenic ED had poor responses compared with those with arteriogenic ED or unremarkable findings with tadalafil 5-mg OaD treatment (14.2% vs 55.0% vs 53.3%). The overall side effects included hot flushing in 9.5%, headache in 7.1%, and dizziness in 2.3% of patients.

CLINICAL IMPLICATIONS

Long-term usage of tadalafil 5 mg OaD after RARP can be an effective option for penile rehabilitation.

STRENGTHS AND LIMITATIONS

The present study is a retrospective study with a relatively small sample.

CONCLUSIONS

Although the responses of patients with venogenic ED were limited compared with those with arteriogenic ED, tadalafil 5-mg OaD treatment was well tolerated and significantly improved EF up to 2 years after NS-RARP. Kim S, Sung GT. Efficacy and Safety of Tadalafil 5 mg Once Daily for the Treatment of Erectile Dysfunction After Robot-Assisted Laparoscopic Radical Prostatectomy: A 2-Year Follow-Up. Sex Med 2018;6:108-114.

Surgical Techniques for Managing Post-prostatectomy Erectile Dysfunction

Purpose of Review

Due to the increasing numbers of radical prostatectomies (RP) performed for prostate cancer, a substantial number of patients are now suffering from post-operative erectile dysfunction (ED). The aim of this study is to summarize the current literature on surgical techniques for managing post-prostatectomy erectile dysfunction.

Recent Findings

The PubMed database was searched for English-language articles published up to Jan 2017 using the following search terms: “prostatectomy AND erectile dysfunction”, “prostatectomy AND penile prostheses”, and “prostatectomy AND penile implants”. All of the studies that evaluated medical treatment were excluded. In the last few decades, the understanding of the anatomy of the male pelvis and prostate has improved. This has led to significant changes in the nerve-sparing radical prostatectomy techniques, with the aim of preserving post-surgical erectile function (EF). In this scenario, the prostate vascular supply and the anatomy of the neurovascular bundles have a central role. Penile prosthesis implantation is considered the third-line treatment option for RP ED patients, and they have been reported to be a very successful treatment with the highest patient satisfaction rate.

Summary

Considering the failure of penile rehabilitation, and the lack of evidence for accessory pudendal artery (APA) preservation and nerve graft, nerve-sparing surgery and penile prostheses represent, today, the only methods to permanently and definitively preserve or erectile function after RP.

Vacuum therapy in penile rehabilitation after radical prostatectomy: review of hemodynamic and antihypoxic evidence

Generally, hypoxia is a normal physiological condition in the flaccid penis, which is interrupted by regular nocturnal erections in men with normal erectile function.1 Lack of spontaneous and nocturnal erections after radical prostatectomy due to neuropraxia results in persistent hypoxia of cavernosal tissue, which leads to apoptosis and degeneration of cavernosal smooth muscle fibers. Therefore, overcoming hypoxia is believed to play a crucial role during neuropraxia. The use of a vacuum erectile device (VED) in penile rehabilitation is reportedly effective and may prevent loss of penile length. The corporal blood after VED use is increased and consists of both arterial and venous blood, as revealed by color Doppler sonography and blood gas analysis. A similar phenomenon was observed in negative pressure wound therapy (NPWT). However, NPWT employs a lower negative pressure than VED, and a hypoperfused zone, which increases in response to negative pressure adjacent to the wound edge, was observed. Nonetheless, questions regarding ideal subatmospheric pressure levels, modes of action, and therapeutic duration of VED remain unanswered. Moreover, it remains unclear whether a hypoperfused zone or PO₂ gradient appears in the penis during VED therapy. To optimize a clinical VED protocol in penile rehabilitation, further research on the mechanism of VED, especially real-time PO₂ measurements in different parts of the penis, should be performed.

The Current Status of Stem-Cell Therapy in Erectile Dysfunction: A Review

Stem cells are undifferentiated cells that are capable of renewal and repair of tissue due to their capacity for division and differentiation. The purpose of this review is to describe recent advances in the use of stem cell (SC) therapy for male erectile dysfunction (ED). We performed a MEDLINE database search of all relevant articles regarding the use of SCs for ED. We present a concise summary of the scientific principles behind the usage of SC for ED. We discuss the different types of SCs, delivery methods, current pre-clinical literature, and published clinical trials. Four clinical trials employing SC for ED have been published. These articles are summarized in this review. All four report improvements in ED after SC therapy. SC therapy remains under investigation for the treatment of ED. It is reassuring that clinical trials thus far have reported positive effects on erectile function and few adverse events. Safety and methodical concerns about SC acquisition, preparation and delivery remain and require continued investigation prior to wide-spread application of these methods.

Erectile dysfunction after radical prostatectomy: prevalence, medical treatments, and psychosocial interventions

PURPOSE OF REVIEW

This review will discuss erectile dysfunction in prostate cancer patients following radical prostatectomy . It will focus on the prevalence and current treatments for erectile dysfunction as well as the emotional impact of erectile dysfunction and the current psychosocial interventions designed to help patients cope with this side effect.

RECENT FINDINGS

Although there is a large discrepancy in prevalence rates of erectile dysfunction after radical prostatectomy, several recent studies have cited rates as high as 85%. The concept of 'penile rehabilitation' is now the standard of practice to treat erectile dysfunction following radical prostatectomy. However, many men avoid seeking help or utilizing erectile dysfunction treatments. This avoidance is related to the shame, frustration, and distress many men with erectile dysfunction and their partners experience. Recent psychosocial interventions have been developed to facilitate the use of treatments and help men cope with erectile dysfunction. These interventions have shown initial promise, however, continued intervention development is needed to reduce distress and improve long-term erectile function outcomes.

SUMMARY

Erectile dysfunction is a significant problem following prostate cancer surgery. Although there are effective medical treatments, the development of psychosocial interventions should continue to evolve to maximize the assistance we can give to men and their partners.

Brain-derived neurotrophic factor promotes nerve regeneration by activating the JAK/STAT pathway in Schwann cells

Background

Radical prostatectomy (RP) carries the risk of erectile dysfunction (ED) due to cavernous nerve (CN) injury. Schwann cells are essential for the maintenance of integrity and function of peripheral nerves such as the CNs. We hypothesize that brain-derived neurotrophic factor (BDNF) activates the Janus kinase (JAK)/(signal transducer and activator of transcription) STAT pathway in Schwann cells, not in neuronal axonal fibers, with the resultant secretion of cytokines from Schwann cells to facilitate nerve recovery.

Methods

Using four different cell lines—human neuroblastoma BE(2)-C and SH-SY5Y, human Schwann cell (HSC), and rat Schwann cell (RSC) RT4-D6P2T—we assessed the effect of BDNF application on the activation of the JAK/STAT pathway. We also assessed the time response of JAK/STAT pathway activation in RSCs and HSCs after BDNF treatment. We then assayed cytokine release from HSCs as a response to BDNF treatment using oncostatin M and IL6 as markers.

Results

We showed extensive phosphorylation of STAT3/STAT1 by BDNF at high dose (100 pM) in RSCs, with no JAK/STAT pathway activation in human neuroblastoma cell lines. The time response of JAK/STAT pathway activation in RSCs and HSCs after BDNF treatment showed an initial peak at shortly after treatment and then a second higher peak at 24–48 hours. Cytokine release from HSCs increased progressively after BDNF application, reaching statistical significance for IL6.

Conclusions

We demonstrated for the first time the indirect mechanism of BDNF enhancement of nerve regeneration through the activation of JAK/STAT pathway in Schwann cells, rather than directly on neurons. As a result of BDNF application, Schwann cells produce cytokines that promote nerve regeneration.

Prevention and management of post prostatectomy erectile dysfunction

Sexual dysfunction is common in patients with prostate cancer (PC) following radical prostatectomy (RP). Review the available literature concerning prevention and management strategies for post-RP erectile function (EF) impairment in terms of preoperative patient characteristics, intra and postoperative factors that may influence EF recovery, and postoperative treatments for erectile dysfunction (ED). A literature search was performed using Google and PubMed database for English-language original and review articles, either published or e-published up to July 2013. The literature still demonstrates a great inconsistency in the definition of what is considered normal EF both before and after RP. Thus, using validated psychometric instruments with recognized cut-offs for normalcy and severity during the pre- and post-operative evaluation should be routinely considered. Therefore, a comprehensive discussion with the patient about the true prevalence of postoperative ED, the concept of spontaneous or pharmacologically-assisted erections, and the difference between “back to baseline” EF and “erections adequate enough to have successful intercourse” clearly emerge as key issues in the eventual understanding of post-RP ED prevention and promotion of satisfactory EF recovery. Patient factors (including age, baseline EF, comorbid conditions status), cancer selection (non- vs. uni- vs. bilateral nerve-sparing), type of surgery (i.e., intra vs. inter vs. extrafascial surgeries), surgical techniques (i.e., open, laparoscopic and robotically-assisted RP), and surgeon factors (i.e., surgical volume and surgical skill) represent the key significant contributors to EF recovery. A number of preclinical and clinical data show that rehabilitation and treatment in due time are undoubtedly better than leaving the erectile tissue to its unassisted postoperative fate. The role of postoperative ED treatment for those patients who received a non-nerve-sparing RP was also extensively discussed. Optimal outcomes are achieved mainly by the careful choice of the correct patient for the correct type of surgery. Despite a plethora of potential rehabilitative approaches, they should be only considered as “strategies”, since incontrovertible evidence of their effectiveness for improving natural EF recovery is limited. Conversely, numerous effective therapeutic options are available for treating post-RP ED.

Pharmacologic and surgical therapies for sexual dysfunction in male cancer survivors

The recent recognition that many men experience sexual dysfunction following their diagnosis and treatment of genitourinary cancers, has led to the development multiple varied strategies that attempt to restore or preserve that function. In this manuscript we review the understanding of why it happens, highlight novel management strategies and discuss the concept of penile rehabilitation (PR) following prostate cancer (PCa) treatment, glans preserving strategies among men diagnosed with penile cancer and address the controversial issue of testosterone therapy in men with PCa.

Neurotrophic Effect of Adipose Tissue-Derived Stem Cells on Erectile Function Recovery by Pigment Epithelium-Derived Factor Secretion in a Rat Model of Cavernous Nerve Injury

The paracrine effect is the major mechanism of stem cell therapy. However, the details of the effect's mechanism remain unknown. The aim of this study is to investigate whether adipose tissue-derived stem cells (ADSCs) can ameliorate cavernous nerve injury-induced erectile dysfunction (CNIED) rats and to determine its mechanism. Twenty-eight days after intracavernous injection of 5-ethynyl-2-deoxyuridine- (EdU-) labeled ADSCs, the erectile function of all the rats was evaluated by intracavernosal pressure (ICP). The ADSCs steadily secreted detectable pigment epithelium-derived factor (PEDF) in vitro. The expression of PEDF increased in the penis of the bilateral cavernous nerve injury (BCNI) group for 14 days and then gradually decreased. On day 28 after the intracavernous injection, the ADSCs group exhibited a significantly increased ICP compared with the phosphate buffered saline- (PBS-) treated group. Moreover, the neuronal nitric oxide synthase (nNOS) and S100 expression in penile dorsal nerves and the smooth muscle content to collagen ratio in penile tissues significantly increased. Furthermore, elevated PEDF, p-Akt, and p-eNOS were identified in the ADSCs group. This study demonstrated that intracavernous injection of ADSCs improved erectile function, repaired the nerve, and corrected penile fibrosis. One potential mechanism is the PEDF secretion of ADSCs and subsequent PI3K/Akt pathway activation.

Tadalafil therapy for erectile dysfunction following prostatectomy

Erectile dysfunction is a major complication affecting the quality of life of patients and partners after radical prostatectomy. Evolving evidence suggests that early penile rehabilitation may provide better erectile function after surgery. Phosphodiesterase type 5 (PDE-5) inhibitors are routinely considered a first-line treatment option in most algorithms for penile rehabilitation owing to their efficacy, ease of use, wide availability and minimal morbidity. Tadalafil is a long-acting, potent PDE-5 inhibitor for erectile dysfunction, with demonstrated effect in animal studies at preserving penile smooth muscle content and prevention of fibrosis of cavernosal tissue. This article evaluates the existing literature on tadalafil and critically analyzes its impact on erectile function following radical prostatectomy.

Improvement in sexual function after robot-assisted radical prostatectomy: A rehabilitation program with involvement of a clinical sexologist

INTRODUCTION

To prospectively evaluate if the inclusion of a clinical sexologist in a penile and sexual rehabilitation program improves sexual function one year after prostate cancer surgery.

MATERIAL AND METHODS

Twelve months after da Vinci Radical Prostatectomy (dVRP) for prostate cancer, 28 fully potent (IIEF-5 >21) and sexually active men (ages 47-69 years, mean 61) who, in 2008, were enrolled in a prospectively monitored penile rehabilitation program (reference group) were compared with 79 fully potent (IIEF-5 >21) and sexually active men (ages 45-74 years, mean 61) enrolled in 2009 (study group); whose program differed by the inclusion of evaluation and treatment by a clinical sexologist.

RESULTS

Twelve months after dVRP, seventeen patients in the reference group (61%) were sexually active with regular penetrating sexual activity compared to sixty-six (84%) in the study group (p = 0.02). These findings were independent of whether they had undergone a nerve sparing or non-nerve sparing procedure. Almost 94% (74 patients) in the study group had at some time been able to perform penetrating sexual activity; 14 patients required additional visits to the clinical sexologist beyond the routine follow-up, 9 for short-term cognitive behavior therapy.

CONCLUSIONS

Inclusion of a clinical sexologist in a penile and sexual rehabilitation program appears to improve the ability to have regular sexual activity with penetrating sex one year after da Vinci Robotic Radical Prostatectomy.

Landmarks in erectile function recovery after radical prostatectomy

The description of the nerve-sparing technique of radical prostatectomy by Walsh was one of the major breakthroughs in the surgical treatment of prostate cancer in the 20(th) century. However, despite this advance and consequent technological refinements to nerve-sparing surgery, a large proportion of men still suffer from erectile dysfunction (ED) as a complication of prostatectomy. A plethora of therapeutic approaches have been proposed to optimize erectile function recovery in these patients. Several preclinical and translational studies have shown benefits of therapies including PDE5 inhibitor (PDE5I) treatment, immunomodulation, neurotrophic factor administration, and regenerative techniques, such as stem cell therapy, in animal models. However, most of these approaches have either failed to translate to clinical use or have yet to be studied in human subjects. Penile rehabilitation with PDE5Is is currently the most commonly used clinical strategy, in spite of the absence of solid clinical evidence to support its use.

Penile rehabilitation after radical prostatectomy: does it work?

CONTEXT

Erectile dysfunction (ED) represents one of the most common long-term side effects in patients with clinically localized prostate cancer (PCa) undergoing nerve-sparing radical prostatectomy (RP).

OBJECTIVE

To analyze the role of penile rehabilitation in the recovery of erectile function (EF) after nerve-sparing RP.

EVIDENCE SYNTHESIS

Penile rehabilitation is defined as the use of any intervention or combination with the goal not only to achieve erections sufficient for satisfactory sexual intercourses, but also to return EF to preoperative levels. The concept of rehabilitation is based on the implementation of protocols aimed at improving oxygenation, preserving endothelial structure, and preventing smooth muscle structural alterations. Nowadays, the most commonly adopted approaches for penile rehabilitation after nerve-sparing RP are represented by the administration of phosphodiesterase type-5 inhibitors (PDE5-Is), intracorporeal injection therapy, vacuum erection devices (VED), and the combination of these therapies. Several basic science studies support the rational for the adoption of penile rehabilitation protocols. Particularly, rehabilitation, set as early as possible, seems to be better than leaving the erectile tissues unassisted. On the other hand, results from solid prospective randomized trials finally assessing the long-term beneficial effects of PDE5-Is, intracavernosal injections, or VED on EF recovery after surgery are still lacking.

CONCLUSIONS

Although preclinical evidences support the rationale for penile rehabilitation after nerve-sparing RP, clinical studies reported conflicting results regarding its efficacy on long-term EF recovery. Nowadays, which is the optimal rehabilitation program still represents a matter of debate.

Prospects of stem cell treatment in benign urological diseases

Stem cells (SCs) are undifferentiated cells that are capable of self-renewal and differentiation and that therefore contribute to the renewal and repair of tissues. Their capacity for division, differentiation, and tissue regeneration is highly dependent on the surrounding environment. Several preclinical and clinical studies have utilized SCs in urological disorders. In this article, we review the current status of SC use in benign urological diseases (erectile dysfunction, Peyronie disease, infertility, and urinary incontinence), and we summarize the results of the preclinical and clinical trials that have been conducted.

Psychosocial perspectives on sexual recovery after prostate cancer treatment

Many therapies for erectile dysfunction (ED) after prostate cancer treatment improve erectile firmness, yet, most couples stop using aids within 1-2 years. Patients and partners who expect immediate and complete success with their first ED treatment can be demoralized when they experience treatment failure, which contributes to reticence to explore other ED aids. Comprehensive patient education should improve sustainability and satisfaction with ED treatments. Pre-emptive and realistic information should be provided to couples about the probability of recovering natural erections. Beginning intervention early and using a couple-based approach is ideal. Recommendations are provided about the timing of ED treatment, the order of aid introduction, and combination therapies. Renegotiation of sexual activity is an essential part of sexual adaptation. From the outset of therapy, couples should be encouraged to broaden their sexual repertoire, incorporate erection-independent sexual activities, and continue to be sexual despite ED and reduced libido.

Current status of penile rehabilitation after radical prostatectomy

Although disease-free survival remains the primary goal of prostate cancer treatment, erectile dysfunction (ED) remains a common complication that affects the quality of life. Even though several preventive and therapeutic strategies are available for ED after radical prostatectomy (RP), no specific recommendations have been made on the optimal rehabilitation or treatment strategy. Several treatment options are available, including phosphodiesterase-5 inhibitors, vacuum erection devices, intracavernosal or intraurethral prostaglandin injections, and penile prostheses. Urologists must consider more effective ways to establish optimal treatments for ED after RP. ED is an important issue among patients with prostate cancer, and many patients hope for early ED recovery after surgery. This review highlights the currently available treatment options for ED after RP and discusses the limitations of each.

Topically applied NO-releasing nanoparticles can increase intracorporal pressure and elicit spontaneous erections in a rat model of radical prostatectomy

INTRODUCTION

Patients undergoing radical prostatectomy (RP) suffer from erectile dysfunction (ED) refractory to phosphodiesterase 5 inhibitors, which act downstream of cavernous nerve (CN)-mediated release of nitric oxide (NO). Direct delivery of NO to the penis could potentially circumvent this limitation.

AIM

This study aimed to determine if topically applied NO-releasing nanoparticles (NO-NPs) could elicit erections in a rat model of RP through increased blood flow.

METHODS

Twenty-six Sprague Dawley rats underwent bilateral transection of the CN. One week later, NO-NPs were applied topically to the penile shaft in dimethylsulfoxide (DMSO) gel (10 animals) or coconut oil (6 animals). Control animals were treated with empty NPs. Erectile function was determined through the intracorporal pressure/blood pressure ratio (ICP/BP). The effect of the NO-NPs on blood flow was determined using a hamster dorsal window chamber.

MAIN OUTCOME MEASURES

Animals were investigated for spontaneous erections, onset and duration of erectile response, and basal ICP/BP ratio. Microcirculatory blood flow was determined through measurements of arteriolar and venular diameter and red blood cell velocity.

RESULTS

Eight of 10 animals treated with NO-NPs suspended in DMSO gel had significant increases in basal ICP/BP, and 6 out of these 10 animals demonstrated spontaneous erections of approximately 1 minute in duration. Time to onset of spontaneous erections ranged from 5 to 37 minutes, and they occurred for at least 45 minutes. Similar results were observed with NO-NPs applied in coconut oil. No erectile response was observed in control animal models treated with empty NPs. The hamster dorsal window chamber experiment demonstrated that NO-NPs applied as a suspension in coconut oil caused a significant increase in the microcirculatory blood flow, sustained over 90 minutes.

CONCLUSIONS

Topically applied NO-NPs induced spontaneous erections and increased basal ICP in an animal model of RP. These effects are most likely due to increased microcirculatory blood flow. These characteristics suggest that NO-NPs would be useful in penile rehabilitation of patients following RP.