Nonsurgical Interventions for Peyronie's Disease: Update as of 2016

Vactosertib, a Novel, Orally Bioavailable Activin Receptor-Like Kinase 5 Inhibitor, Promotes Regression of Fibrotic Plaques in a Rat Model of Peyronie's Disease

Purpose

To examine the therapeutic effect of Vactosertib, a small molecule inhibitor of transforming growth factor-β (TGF-β) type I receptor (activin receptor-like kinase-5, ALK5), in an experimental model of Peyronie's disease (PD) and determining anti-fibrotic mechanisms of Vactosertib in primary fibroblasts derived from human PD plaques.

Materials and Methods

Male rats were randomly divided into three groups (n=6 per group); control rats without treatment; PD rats receiving vehicle; and PD rats receiving Vactosertib (10 mg/kg). PD-like plaques were induced by administering 100 µL of each of human fibrin and thrombin solutions into the tunica albuginea on days 0 and 5. Vactosertib was given orally five times a week for 2 weeks. On day 30, we performed electrical stimulation of the cavernous nerve to measure erectile function, and the penis was obtained for histological examination. Fibroblasts isolated from human PD plaques were used to determine the anti-fibrotic effects of Vactosertib in vitro.

Results

Vactosertib induced significant regression of fibrotic plaques in PD rats in vivo through reduced infiltration of inflammatory cells and reduced expression of phospho-Smad2, which recovered erectile function. Vactosertib also abrogated TGF-β1-induced enhancement of extracellular matrix protein production and hydroxyproline content in PD fibroblasts in vitro by hindering the TGF-β1-induced Smad2/3 phosphorylation and nuclear translocation, and fibroblast-to-myofibroblast transdifferentiation.

Conclusions

In view of the critical role of TGF-β and the Smad pathway in the pathogenesis of PD, inhibition of this pathway with an ALK5 inhibitor may represent a novel, targeted therapy for PD.

Anti-fibrotic effect of mycophenolate mofetil on Peyronie's disease experimentally induced with TGF-β

The aim of the present study was to evaluate the histological, histochemical, and stereological changes caused by mycophenolate mofetil (MMF) on the tunica albuginea of rat penises submitted to an injection of transforming growth factor beta (TGF-β) for the induction of Peyronie's disease (PD). Twenty adult male Wistar rats were divided into four groups: Control group; TGF-β group (TGF-β injection); MMF-7d group (treated with MMF 7 days after induction with TGF-β); and MMF-30d group (treated with MMF 30 days after induction with TGF-β). The steorological evaluation included the relative volume of different types of connective fibres of the tunica albuginea. The histochemical analysis revealed the fragmentation and degradation of elastin in the tunica albuginea. This process was partially reversed in the MMF-7d group and a situation very close to normality was observed in the MMF-30d group. In the collagen III/collagen I ratio it was observed increase in this ratio in the TGF-β (59.4 ± 5.53) and MMF-7d (49 ± 18.2) groups and a decrease in the MMF-30d group (28.7 ± 4), approaching normality. The injection of TGF-β promoted fibrotic alterations in the penile tunica albuginea in Wistar rats corresponding to PD. In this model, MMF acts as a regenerating anti-fibrotic agent.

Intratunical Injection of Human Adipose Tissue-Derived Stem Cells Restores Collagen III/I Ratio in a Rat Model of Chronic Peyronie's Disease

Introduction

Previous studies have shown that the injection of adipose tissue–derived stem cells (ADSCs) into the tunica albuginea (TA) during the active phase of Peyronie’s disease (PD) prevents the development of fibrosis.

Aim

To investigate, using an animal model, whether local injection of human ADSCs (hADSCs) can alter the degree of fibrosis in the chronic phase of PD.

Methods

27 male, 12-week-old rats were divided into 3 equal groups: sham, PD without treatment, and PD treated with hADSCs 1 month after disease induction. Sham rats underwent 2 injections of vehicle into the TA 1 month apart. PD rats underwent transforming growth factor β1 (TGFβ1) injection and injection of vehicle 1 month later. PD-hADSC rats underwent TGFβ1 injection followed by 1 million hADSCs 1 month later. 1 week after treatment, n = 3 animals/group were euthanized, and the penises were harvested for quantitative polymerase chain reaction. 1 month after treatment, the other animals, n = 6 per group, underwent measurement of intracavernous pressure (ICP) and mean arterial pressure (MAP) during electrostimulation of the cavernous nerve. After euthanasia, penises were again harvested for histology and Western blot.

Main Outcome Measure

The primary outcome measures included (a) gene expression at one week post-injection; (b) measurement of ICP/MAP upon cavernous nerve stimulation as a measure of erectile function; (c) elastin, collagen I and III protein expression; and (d) Histomorphometric analysis of the penis. Means where compared by analysis of variance (ANOVA) followed by a Student-Newman-Keuls test for post hoc comparisons or Mann-Whitney test when applicable.

Results

No significant difference was noted in ICP or ICP/MAP in response to cavernous nerve electrostimulation between the 3 groups at 2.5, 5, and 7.5 V (P > .05 for all voltages). PD animals developed tunical and subtunical areas of fibrosis with a significant upregulation of collagen III protein. The collagen III/I ratio was higher in the PD (4.6 ± 0.92) group compared with sham (0.66 ± 0.18) and PD-hADSC (0.86 ± 0.06) groups (P < .05) These fibrotic changes were prevented when treated with hADSCs. Compared with PD rats, PD-hADSC rats demonstrated a decreased expression of several fibrosis-related genes.

Conclusion

Injection of hADSCs reduces collagen III expression in a rat model of chronic PD.

Castiglione F, Hedlund P, Weyne E, et al. Intratunical Injection of Human Adipose Tissue–Derived Stem Cells Restores Collagen III/I Ratio in a Rat Model of Chronic Peyronie’s Disease. Sex Med 2019;7:94–103.

Sonographic patterns of Peyronie's disease in patients with absence of palpable plaques

PURPOSE

Non-palpable isolated septal plaques of the penis are likely present in a significant number of patients affected by erectile dysfunction (ED) and penile pain without deformity or curvature. The aim of this study was to evaluate the ultrasound (US) patterns observed in patients investigated for ED or penile pain without curvature.

MATERIALS AND METHODS

We reviewed the medical records of 386 patients who underwent an initial colour-Doppler ultrasonography (CDU) of the penis for DE and/or penile pain without curvature. After satisfying inclusion criteria, 41 patients were individualized. All patients had a non-palpable plaque with involvement of the penile septum. Three US patterns were identified: focal hyperecoic thickening of the intercavernosum septum (IS) with acoustic shadow (pattern 1), non-calcified thickening (isoechoic or slightly hyperechoic (pattern 2), and microcalcifications in the IS without associated acoustic shadow (pattern 3).

RESULTS

Patients' mean age was 51.3±16.7. ED was the predominant disorder in 73.2% of patients, followed by penile pain and length loss in 19.5% and 7.3% of patients, respectively. 32(78.1%) patients showed the pattern 1, 6 (14.6%) pattern 2, and 3 (7.3%) pattern 3. Plaques size varied from 3 to 13 mm. The penile hemodynamic response to CDU reported abnormal findings distally to the septal plaques in 20 patients (<25cm/sec). Median left and right cavernosum artery flows measured a peak systolic velocity of 31cm/sec and 33 cm/sec, respectively.

CONCLUSIONS

We believe that an US study with CDU provides a way to characterize, localize, and deliver treatment choice in patients with Peyronie's Disease.

Silencing Histone Deacetylase 7 Alleviates Transforming Growth Factor-β1-Induced Profibrotic Responses in Fibroblasts Derived from Peyronie's Plaque

Purpose

Epigenetic modifications, such as histone acetylation/deacetylation and DNA methylation, play a crucial role in the pathogenesis of inflammatory disorders and fibrotic diseases. The aim of this study was to study the differential gene expression of histone deacetylases (HDACs) in fibroblasts isolated from plaque tissue of Peyronie's disease (PD) or normal tunica albuginea (TA) and to examine the anti-fibrotic effect of small interfering RNA (siRNA)-mediated silencing of HDAC7 in fibroblasts derived from human PD plaque.

Materials and Methods

For differential gene expression study, we performed reverse-transcriptase polymerase chain reaction for HDAC isoforms (1–11) in fibroblasts isolated from PD plaque or normal TA. Fibroblasts isolated from PD plaque were pretreated with HDAC7 siRNA (100 pmol) and then stimulated with transforming growth factor-β1 (TGF-β1, 10 ng/mL). Protein was extracted from treated fibroblasts for Western blotting. We also performed immunocytochemistry to detect the expression of extracellular matrix proteins and to examine the effect of HDAC2 siRNA on the TGF-β1-induced nuclear translocation of Smad2/3 and myofibroblastic differentiation.

Results

The mRNA expression of HDAC2, 3, 4, 5, 7, 8, 10, and 11 was higher in fibroblasts isolated from PD plaque than in fibroblasts isolated from normal TA tissue. Knockdown of HDAC7 in PD fibroblasts inhibited TGF-β1-induced nuclear shuttle of Smad2 and Smad3, transdifferentiation of fibroblasts into myofibroblasts, and abrogated TGF-β1-induced production of extracellular matrix protein.

Conclusions

These findings suggest that specific inhibition of HDAC7 with RNA interference may represent a promising epigenetic therapy for PD.

Collagenase Clostridium histolyticum in the Treatment of Peyronie's Disease-A Review of the Literature and a New Modified Protocol

INTRODUCTION

Peyronie's disease (PD) is a common condition that results in penile deformity, which makes sexual intercourse difficult or impossible, and causes psychological, emotional, and relationship difficulties for the man affected and his partner. Collagenase Clostridium histolyticum (CCH; Xiapex, Xiaflex) is the first licensed non-surgical treatment option for PD. The safety and efficacy have been demonstrated in two large phase III randomized controlled trials (IMPRESS I and IMPRESS II).

AIM

To review the safety and efficacy of CCH and to introduce a new shortened modified protocol for CCH that was developed by the authors to decrease the cost and duration of treatment.

METHODS

A review of the medical literature on CCH for inclusion in this review was obtained by searching the PubMed (from 1946) and Medline (from 1946) medical databases and from the screening of relevant bibliographies. The search terms Xiapex, Xiaflex, collagenase Clostridial histolyticum, and Peyronie's disease were used. Clinical trials in men with PD and scientific articles relating to pharmacologic data were included in the review. When possible, large, randomized, and well-designed trials were selected.

MAIN OUTCOME MEASURES

Changes in the angle of penile curvature and in the Peyronie's Disease Questionnaire domains.

RESULTS

The clinical trials demonstrate the safety and efficacy of CCH in the treatment of PD. The new modified protocol developed by the authors is as safe and effective as the protocol used in the clinical trials.

CONCLUSION

CCH is the first licensed non-surgical treatment for PD. Its safety and efficacy have been demonstrated in large well-designed clinical trials. The new shortened modified protocol decreases the cost and duration of the treatment without compromising the safety and efficacy of the drug. This alteration will allow more patients to benefit from CCH. Abdel Raheem A, Johnson M, Abdel-Raheem T, et al. Collagenase Clostridium histolyticum in the Treatment of Peyronie's Disease-A Review of the Literature and a New Modified Protocol. Sex Med Rev 2017;5:529-535.