Mechanisms of Disease: new insights into the cellular and molecular pathology of Peyronie's disease

Characterization of a novel rabbit model of Peyronie's disease

Peyronie's disease (PD) is a debilitating pathology which is associated with penile curvature and erectile dysfunction due to the formation of fibrotic plaques in the penile tunica albuginea. In the present study, we developed a novel rabbit model of PD via subtunical injection of recombinant transforming growth factor (TGF)-β1 protein and characterized erectile function and histopathological endpoints following plaque formation. Ten adult male, New Zealand white rabbits were randomized into 3 experimental groups including nonsurgical controls (NSC, N = 3) and those receiving subtunical injections of vehicle (N = 3) or TGF-β1 protein (0.5 µg/50 µl; N = 4). Following 1 month post-op, focal fibrous plaques composed of disorganized collagen type I and III bundles as well as fragmented elastin fibers at TGF-β1 injection sites were observed in contrast to control groups. Cavernosometric and cavernosographic evaluations revealed no significant differences in maximum intracorporal pressures or substantial curvature during papaverine-induced erection in either the vehicle or TGF-β1 cohorts. Immunohistochemical and histomorphometric analyses demonstrated significant increases in elastase 2B expression in TGF-β1-induced plaques as well as significant declines in matrix metalloproteinase (MMP)-2 and -9 expression relative to control levels. Our results demonstrate that PD-like fibrotic plaques can be created in the rabbit penile tunica albuginea following TGF-β1 injection.

Research advances in Peyronie's disease: a comprehensive review on genomics, pathways, phenotypic manifestation, and therapeutic targets

INTRODUCTION

Penile induration disease, commonly known as Peyronie's disease (PD), is a connective tissue disorder that affects the penis, leading to the development of fibrous plaques, penile curvature, and erectile dysfunction. PD is a common male reproductive system disease with a complex etiology involving multiple genes, signaling pathways, and different phenotypes.

OBJECTIVES

The etiology and pathogenesis of PD remain poorly understood, hindering the development of effective treatment strategies. By understanding the underlying mechanisms of PD, we can pave the way for targeted therapies and improved patient outcomes.

METHODS

We reviewed the epidemiology and pathophysiology of PD. We performed database searches on Google Scholar, PubMed, Medline, and Web of Science from inception to September 2023. The literature reviewed included priapism guidelines, review articles, current trial studies, and various literature related to PD.

RESULTS

This article provides a comprehensive overview of the current research progress on the disease, focusing on its genetic factors, signaling pathways, cellular mechanisms, phenotypic manifestations, and therapeutic targets. It can help identify individuals at higher risk, aid in early detection and intervention, and provide insights into fibrosis and tissue remodeling. It can also reveal potential therapeutic targets, guide accurate diagnoses and treatment strategies, and address the impact of the disease on patients' quality of life.

CONCLUSION

By integrating insights from genomics, molecular pathways, clinical phenotypes, and therapeutic potentials, our research aims to achieve a deeper and more comprehensive understanding of PD, propelling the field toward innovative strategies that enhance the lives of those affected by PD. The complex manifestations and pathogenesis of PD necessitate the use of multiple treatment methods for personalized care.

Medical Treatment for Peyronie's Disease: Systematic Review and Network Bayesian Meta-Analysis

PURPOSE

To investigate the efficacy of medical treatment options for Peyronie's disease (PD) including oral drugs, intralesional treatment and mechanical treatment compared with placebo treatment using network meta-analysis (NMA).

MATERIALS AND METHODS

We searched the randomized controlled trials (RCTs) of PD in PubMed, Cochrane library, and EMBASE up to October 2022. RCTs included medical treatment options: oral drugs, intralesional treatment and mechanical treatment. Studies reporting at least one of the outcome measures of interest including curvature degree, plaque size, and structured questionnaires (International Index of Erectile Function, IIEF) were included.

RESULTS

Finally, 24 studies including 1,643 participants met our selection criteria for NMA. There was no statistically significant treatment compared to placebo of the curvature degree, plaque size, IIEF in Bayesian analysis. The SUCRA values of ranking probabilities for each treatment performance, which indicated that hyperthermia device ranked first in NMA. However, in frequentist analysis, 7 of mono treatments (coenzyme Q10 [CoQ10] 300 mg, hyperthermia device, interferon alpha 2b, pentoxifylline 400 mg, propionyl-L-carnitine 1 g, penile traction therapy [PTT], vitamin E 300 mg) and 2 of combination treatments ("PTT-extracorporeal shockwave treatment", "vitamin E 300 mg-propionyl-L-carnitine 1 g") were statistically significant for improvement of curvature degree, and 9 of mono treatments (CoQ10 300 mg, hyaluronic acid 16 mg, hyperthermia device, interferon alpha 2b, pentoxifylline 400 mg, propionyl-L-carnitine 1 g, verapamil 10 mg, vitamin E 300 mg, vitamin E 400 U) and 3 of combination treatments ("interferon alpha 2b-vitamin E 400 U", "verapamil 10 mg-antioxidants", "vitamin E 300 mg-propionyl-L-carnitine 1 g") were statistically significant in the improvement of plaque size.

CONCLUSIONS

At present, there is no clinical treatment alternatives that have been demonstrated to be effective compared to placebo. Nonetheless, as the frequentist approach has shown that a number of agents are efficacious, further research is expected to develop more effective treatment options.

Which inflammatory marker, between systemic immune-inflammation index and neutrophil to eosinophil ratio, is associated with Peyronie's disease and are there any implications for a better understanding of its mechanisms?

BACKGROUND

Peyronie's disease affects up to 9% of men and is often accompanied by pain and/or erectile dysfunction. It is characterized by an inflammatory process that is the grassroots of the subsequent fibrosis stage. There is an unmet need to evaluate its onset and progression. Among the newly proposed biomarkers of inflammation, authors developed a novel systemic immune-inflammation index (SII) based on lymphocyte, neutrophil, and platelet counts. Similarly, a recent study reported that a neutrophil-to-eosinophil ratio (NER) represents systemic inflammation.

RESULTS

A 49-patient group with Peyronie's disease as confronted with 50 well-matched for age and BMI controls. As laboratory evaluation of inflammation, SII, NER and the eosinophil to neutrophil ratio (ENR) were studied. As a likely risk factor for the presence of Peyronie's disease, a higher prevalence of hypercholesterolemia, hyperglycemia and hypertension was discovered in the patients compared to controls. A significant difference was found in the median values of the NER between the two selected groups, i.e., 32.5 versus 17.3 (p = 0.0021). As expected, also ENR was significantly different. The receiver operating characteristic curves for SII, ENR and NER were 0.55, 0.32 and 0.67, respectively, highlighting the best performance of NER. The cut-off for NER was 12.1, according to the Youden test.

CONCLUSIONS

According to our results, any evaluation of circulating eosinophil, evaluated as NER, beyond being a signature of immuno-inflammatory response, help assess tissue homeostasis, since eosinophils are now considered multifunctional leukocytes and give a picture of the inflammatory process and repair process belonging to Peyronie's disease.

A systematic review of non-surgical management in Peyronie's disease

The efficacy of many non-surgical treatments for Peyronie's disease is unclear. This systematic review aims to critically assess the currently available options and provide a recommendation for treatment based on this. A systematic literature search utilising the Medline (Pubmed), Embase, global health and Cochrane library databases was conducted up to May 2021. All randomised controlled trials assessing non-surgical treatment modalities for Peyronie's Disease were included. Individual study risk of bias was evaluated using the Cochrane tool and GRADE was used to assess evidence strength. Outcome measures were the change in penile curvature (degrees), plaque size (volume or size), International Index of Erectile Function score, pain scores and change in penile length. Prospero registration number: CRD42017064618. Amongst the 5549 articles identified, 41 studies (42 reports) were included. Seven different oral treatment options including vitamin E supplementation showed evidence for improving outcomes such as penile curvature and plaque size. Of the intralesional treatments, Collagenase Clostridium Histolyticum showed evidence for improving penile curvature (Range: 16.3-17 degrees, moderate level certainty of evidence). Intralesional Interferon demonstrated some improvement in curvature (Range: 12-13.5 degrees), plaque size (Range: 1.67-2.2 cm2) and pain, whilst intralesional calcium channel blockers such as Verapamil showed variable evidence for changes in the plaque size and pain. Extracorporeal Shockwave Therapy consistently demonstrated evidence for improving penile pain in stable disease, and two mechanical traction devices improved curvature. Iontophoresis, topical medications, and combination therapies did not demonstrate any consistent improvements in outcome measures. Intralesional options demonstrate the best potential. Overall, results varied with few high-quality randomised trials present.

European Society of Sexual Medicine consensus statement on the use of animal models for studying Peyronie's disease

Introduction

Animal models are frequently used for translational research in Peyronie's disease (PD). However, due to lack of availability of guidelines, there is some heterogeneity in study design, data reporting, and outcome measures.

Aim

This European Society for Sexual Medicine consensus statement aims to provide guidance in utilization of animal models in PD research in a standardized and uniform fashion.

Methods

PubMed was searched for studies using animal models for PD. The following search terms were used: ("Peyronie's disease" OR "penile fibrosis" OR "penile curvature" OR "induration penis plastica" OR "erectile dysfunction") AND ("rodent" OR "mouse" OR "mice" OR "rat" OR "rabbit").

Outcomes

This European Society for Sexual Medicine statement describes best practice guidelines for utilization of animals in PD research: power calculation, details of available models, surgical procedures, and measurement techniques, while highlighting possible pitfalls and translational limitations of the models.

Results

In total, 2490 studies were retrieved and 2446 articles were excluded. A total of 44 studies were included, of which 40 studies used rats, 1 study used both rats and mice, 1 study used a genetic mouse model, and 2 studies used rabbits. A significant number of the studies (70.5%) used transforming growth factor β 1 for induction of fibrosis. Oxford 2011 Levels of Evidence criteria could not be applied due to the nature of the studies.

Conclusion

Despite certain limitations of PD animal models presented, we aimed to provide guidance for their appropriate use in translational research, with the purpose of improving study quality and reproducibility as well as facilitating interpretation of reported results and conclusions.

Fibrotic Diseases of the Human Urinary and Genital Tract: Current Understanding and Potential Strategies for Treatment

Fibrosis is a disease condition characterized by abnormalities of the extracellular matrix, such as accumulation of the transforming growth factor β, infiltration by myofibroblasts, deposition of collagen, and a generalized dysregulation of collagen maturation. It can severely impair the function of organs by replacing normal tissue with a highly collagenized matrix, thereby reducing the elasticity and compliance of tissues. Fibrotic diseases of the genitourinary tract present relevant problems in healthcare, and their principles of pathophysiology remain unclarified; hence, the armamentarium for prevention and treatment is limited. These diseases include renal fibrosis, Peyronie's disease and ureteral and urethral strictures due to perturbations in the process of wound healing in response to injuries. Such deteriorations may contribute to obstructive uropathies or sexual dysfunction. This review provides a brief overview of the most frequent fibrotic diseases of the genitourinary system and of how the pathophysiology is related to symptoms, and also highlights potential therapeutic strategies to address the abnormal deposition of collagen. Although the understanding of factors associated with fibrotic conditions of the urinary and genital tract is still limited, some beneficial advances have been made. Further research will serve to provide a more comprehensive insight into factors responsible for the development of fibrotic tissue deposition.

Penile Autophotography Underestimates the Degree of Penile Curvature in Peyronie's Disease

BACKGROUND

Penile curvature is the most debilitating symptom of Peyronie's disease (PD); the evaluation of the degree of angulation is essential for planning treatment strategy. However, the most used method of penile at-home autophotography (AHP) is associated with some potential pitfalls and discrepancies compared with different assessment methods.

OBJECTIVE

To compare the degree of penile curvature quantified by AHP and in-office intracavernosal alprostadil injection (ICI) prior to therapy.

DESIGN, SETTING, AND PARTICIPANTS

Data from 55 PD patients of a single tertiary referral center were analyzed. All patients provided standardized AHP of the erect phallus. Clinic-based assessment included ICI with curvature measurement and completion of the International Index of Erectile Function (IIEF-15).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The Wilcoxon and/or chi-square test was used to compare the degree of curvature obtained using AHP and ICI, and to evaluate whether erectile dysfunction was a predictor of a relevant difference of >10° in curvature assessment between AHP and ICI.

RESULTS AND LIMITATIONS

Our study showed a significant (p < 0.001) difference in the degree of penile curvature between AHP (48° [38°; 55°]) and ICI (50° [40°; 65°]). Patients suffering from erectile dysfunction tend to have a higher difference in the degree of penile curvature between AHP and ICI than patients with good erectile function (p < 0.001). Our study is not devoid of limitations. First, we did not use Peyronie's Disease Questionnaire, as suggested by the European Association of Urology guidelines. Second, we did not evaluate inter- and intraobserver variations in the measurements.

CONCLUSIONS

AHP tends to underestimate the extent of penile curvature compared to ICI. Erectile dysfunction is an independent predictor of measurement differences of >10° between AHP and ICI.

PATIENT SUMMARY

It is necessary to evaluate the degree of penile curvature in Peyronie's disease prior to therapy decision. The at-home self-photography underestimates the real degree of penile curvature compared with an erection by in-office penile drug injection. Especially men suffering from erectile dysfunction carry the risk of a high difference in the measured degree of penile curvature, with a potential impact on the further treatment.

The Function of BDNF and Its Receptor in the Male Genitourinary System and Its Potential Clinical Application

Background: Brain-derived neurotrophic factor (BDNF), as a member of the nerve growth factor family, has been mentioned more and more frequently in recent literature reports. Among them, content about the male genitourinary system is also increasing. Objective and Rationale: BDNF plays an important role in the male genitourinary system. At the same time, the literature in this field is constantly increasing. Therefore, we systematically summarized the literature in order to more intuitively show the function of BDNF and its receptor in the male genitourinary system and its potential clinical application. Search Methods: An electronic search of, e.g., PubMed, scholar.google and Scopus, for articles relating to BDNF and its receptor in the male genitourinary system. Outcomes: In the male genitourinary system, BDNF and its receptors TrkB and p75 participate in a series of normal physiological activities, such as the maturation and morphogenesis of testes and epididymis and maintenance of isolated sperm motility. Similarly, an imbalance of the circulating concentration of BDNF also mediates the pathophysiological process of many diseases, such as prostate cancer, benign prostatic hyperplasia, male infertility, diabetes erectile dysfunction, penile sclerosis, and bladder fibrosis. As a consequence, we conclude that BDNF and its receptor are key regulatory proteins in the male genitourinary system, which can be used as potential therapeutic targets and markers for disease diagnosis.

Role of Oxidative Stress in Peyronie's Disease: Biochemical Evidence and Experiences of Treatment with Antioxidants

BACKGROUND

Peyronie's disease (PD) is a chronic inflammatory condition affecting adult males, involving the tunica albuginea of the corpora cavernosa of the penis. PD is frequently associated with penile pain, erectile dysfunction, and a secondary anxious-depressive state. The etiology of PD has not yet been completely elucidated, but local injury is generally recognized to be a triggering factor. It has also been widely proven that oxidative stress is an essential, decisive component in all inflammatory processes, whether acute or chronic. Current conservative medical treatment comprises oral substances, penile injections, and physical therapy.

AIM

This article intends to show how antioxidant therapy is able to interfere with the pathogenetic mechanisms of the disease.

METHOD

This article consists of a synthetic narrative review of the current scientific literature on antioxidant therapy for this disease.

RESULTS

The good results of the antioxidant treatment described above also prove that the doses used were adequate and the concentrations of the substances employed did not exceed the threshold at which they might have interacted negatively with the mechanisms of the redox regulation of tissue.

CONCLUSIONS

We believe new, randomized, controlled studies are needed to confirm the efficacy of treatment with antioxidants. However, we consider the experiences of antioxidant treatment which can already be found in the literature useful for the clinical practice of urologists in the treatment of this chronic inflammatory disease.

Use of penile shear wave elastosonography for the diagnosis of Peyronie's Disease: a prospective case-control study

BACKGROUND

To evaluate the stiffness of the tunica albuginea (TA), we used a new noninvasive diagnostic technique called shear wave elastography (SWE). We determined whether SWE values are correlated with the degree of penile curvature, the time of disease onset, and pain severity experienced by patients during erection. This study analyzed the elasticity of the TA of patients with Peyronie's disease compared to that of the control group. We also analyzed any correlations between the stiffness of the cavernous bodies and the degree of curvature, time from diagnosis to curvature onset, and erectile pain severity. This was a prospective case-control study involving 100 men enrolled from September 2020 to August 2021. Participants were divided into group A (case group, n = 50), which included men with PD, with or without pain, and with penile curvature, or group B (control group, n = 50), which included healthy patients older than 18 years who visited the urology clinic for reasons other than PD. The medical history was collected for all patients who also underwent objective examination, B-mode ultrasound evaluation, and SWE. The International Index of Erectile Function (IIEF-15) visual analog scale (VAS) questionnaire was administered to all participants.

RESULTS

There were no significant between-group differences regarding age, weight, and height (p > 0.05); however, there was a significant difference in the stiffness values (p < 0.05). An inverse correlation was observed between stiffness and the VAS score (p < 0.0001). A positive correlation was observed between the degree of curvature (p < 0.0001) and the time of curvature onset (p < 0.0001). The IIEF-15 scores were poorer in group A than in group B (p < 0.0001).

CONCLUSION

SWE is an inexpensive, noninvasive method that can be used to measure the stiffness of PD patients.

Global Perspective on the Management of Peyronie's Disease

Introduction

Peyronie's disease is the disease that results in an alteration in the curvature of the penis, which can lead to a shortening of length, pain in erection, or difficulties in penetration, thus leading the patient to psychological alterations due to loss of functionality such as aesthetic alteration. That is why there are several studies to define the best form of treatment, which currently continues to be the first choice surgical treatment.

Objective

We present the most recommended therapies for Peyronie's disease and suggest an algorithm as a guide to direct therapy.

Methods

We used the PubMed platform to review the literature related to Peyronie's disease. Various editorials were reviewed as well as original articles and reviews focusing on the various treatments as well as their indications and results.

Results

Peyronie's disease in which conservative or drug treatment does not have a response, surgical treatment with corporoplasty, penile prosthesis implantation or both may be indicated. Corporoplasty refers to both the plication of the tunica albuginea as well as the incision of the tunica with the placement of a graft. An accurate history should always be carried out to identify erectile dysfunction as well as to be able to guide you on the repercussions of the treatment. If refractory erectile dysfunction is present, placement of a penile prosthesis with or without further adjunctive straightening maneuvers is recommended. We reviewed the indications, advantages, disadvantages, and results of the available techniques, and proposed a surgical treatment algorithm.

Conclusion

Penile shortening procedures are usually indicated in curvatures <60°, in penises with adequate length. Partial excision/incision and grafting are indicated for curvatures >60°, hourglass or hinge deformities, and short penises, if the patient's erectile function is adequate. The presence of “borderline” erectile function and/or ventral curvature tilts the choice toward shortening procedures, and refractory erectile dysfunction is an indication for penile prosthesis placement. An accurate risk/benefit assessment of the individual patient as well as meticulous patient counseling are critically important.

The contribution of the immune system to genitourinary fibrosis

Fibrotic diseases of the genitourinary tract are devastating and incompletely understood pathologies. These diseases include urethral and ureteral strictures, retroperitoneal fibrosis, and Peyronie's disease. They can contribute to obstructive uropathy and sexual dysfunction. Poor understanding of the pathophysiology of these diseases severely limits our ability to prevent and treat them. Genitourinary fibrotic diseases likely represent related pathologies that share common underlying mechanisms involving wound healing in response to injury. These diseases share the common feature of extracellular matrix abnormalities-such as collagen deposition, transforming growth factor-β accumulation, and dysregulation of collagen maturation-leading to abnormal tissue stiffness. Given the association of many of these diseases with autoimmunity, a systemic pro-inflammatory state likely contributes to their associated fibrogenesis. Herein, we explore the immunologic contribution to fibrogenesis in several fibrotic diseases of the genitourinary system. Better understanding how the immune system contributes to fibrosis in these diseases may improve prevention and therapeutic strategies and elucidate the functions of immunologic contributors to fibrosis in general.

Pharmacotherapy in Peyronie's disease: a state-of-the-art review on established contemporary and emerging drugs

INTRODUCTION

Current clinical guidelines on Peyronie's disease (PD) advocate non-surgical treatment options as the first-line therapy despite inconsistent clinical outcomes when compared to definitive penile reconstructive surgery.

AREAS COVERED

This article examines the current understanding of established contemporary and emerging pharmacotherapies for PD. Emphasis has been placed on published clinical studies on drugs in the last 10 years.

EXPERT OPINION

Published studies have shown that combination therapy is likely more effective than monotherapy. Combined treatment modalities involving various oral and/or intralesional pharmacotherapies together with mechanical devices or clinical psychosexual therapy may provide additional or synergistic benefits for PD patients. A multidisciplinary approach coupled with more novel targets for pharmacological intervention could deliver a more effective treatment paradigm to prevent or at least delay the need for definitive penile reconstructive surgery. Drugs targeting the inhibition of TGF-β1 pathway and myofibroblast transformation are of great interest and studies into next-generation genetic sequencing and transcriptional biomarker regulatory pathways in PD will provide useful insights into the pathophysiology of PD, and assist the development of future regenerative technology including cellular-based therapies to target various anti-fibrotic molecular mechanisms and the potential to be integrated into existing treatment armamentarium for PD.

ESSM Position Statement on Surgical Treatment of Peyronie's Disease

INTRODUCTION

Patients with Peyronie's disease may experience significat distress. The choice of treatment depends on a variety of factors, including the stage of the disease, the presence of pain, severity and direction of the curvature, penile length and the quality of erectile function.

AIM

To review the evidence associated with surgical treatment of Peyronie`s Disease and provide clinical recommendations on behalf of the European Society for Sexual Medicine. 131 peer-reviewed studies and systematic reviews, which were published from 2009 to 2019 in the English language, were included.

METHODS

MEDLINE, Google Scholar and EMBASE were searched for randomized clinical trials, meta-analyses, open-label prospective and retrospective studies.

MAIN OUTCOME MEASURE

The panel provided statements on clinically relevant questions including patient involvement in the decision process, indications for surgery, choice of the approach, and the management of patient expectations. A comparison of the different grafts used in patients who have undergone plaque incision/excision and grafting in order to identify an ideal graft, has been carried out. The prevalence of postoperative complications has been summarized. Levels of evidence were provided according to the Oxford 2011 criteria and Oxford Centre for Evidence-Based Medicine recommendations.

RESULTS

In order to allow shared decision making, a patient preoperative counselling regarding the pros and cons of each intervention is recommended. In particular, adverse effects of surgical treatments should be discussed to set realistic understanding and expectations of surgical outcomes and ultimately improve postoperative satisfaction rates. Surgical treatment should be only offered in the chronic phase of the condition, when the deformity and/or degree of erectile dysfunction, prevent patients from engaging in satisfying sexual interaction, or if the deformity is the cause of severe bother.

CONCLUSIONS

Current European Society for Sexual Medicine recommendations cover several aspects of Peyronie's disease treatment. These recommendations aim both to ensure patients and partners have accurate and realistic expectations of their treatment options, as well as to formulate algorithms to guide clinician management pathways. Osmonov D. et al., ESSM Position Statement on Surgical Treatment of Peyronie's Disease. Sex Med 2022;10:100459.

Pathological Significance of Macrophages in Erectile Dysfunction Including Peyronie's Disease

Erectile function is regulated by complex mechanisms centered on vascular- and nerve-related systems. Hence, dysregulation of these systems leads to erectile dysfunction (ED), which causes mental distress and decreases the quality of life of patients and their partners. At the molecular level, many factors, such as fibrosis, lipid metabolism abnormalities, the immune system, and stem cells, play crucial roles in the etiology and development of ED. Although phosphodiesterase type 5 (PDE5) inhibitors are currently the standard treatment agents for patients with ED, they are effective only in a subgroup of patients. Therefore, further insight into the pathological mechanism underlying ED is needed to discuss ED treatment strategies. In this review, we focused on the biological and pathological significance of macrophages in ED because the interaction of macrophages with ED-related mechanisms have not been well explored, despite their important roles in vasculogenic and neurogenic diseases. Furthermore, we examined the pathological significance of macrophages in Peyronie’s disease (PD), a cause of ED characterized by penile deformation (visible curvature) during erection and pain. Although microinjury and the subsequent abnormal healing process of the tunica albuginea are known to be important processes in this disease, the detailed etiology and pathophysiology of PD are not fully understood. This is the first review on the pathological role of macrophages in PD.

Molecular Mechanisms and Current Pharmacotherapy of Peyronie's Disease: A Review

Peyronie’s disease (PD) is a localized fibrotic lesion of the penis that has adverse effects on men’s health. In this review, we summarized the molecular mechanisms and pharmacotherapies of PD. A literature search was conducted using PubMed and Cochrane Library during 2001–2020. Although no oral or topical medication demonstrated efficacy in monotherapy of PD, several intralesional medications have yielded promising results. Currently, the effective strategy in management of PD should be combined modality therapy, including but not limited to pharmacotherapy, mechanical therapy, and psychotherapy. Meanwhile, basic research is still necessary to facilitate the development of novel and more reliable treatments. In future, more attention should be given simultaneously to epigenetic changes, inflammatory cytokines, the abnormal wound-healing process, and profibrotic and anti-fibrotic factors to provide more options for this refractory disease.

Single-cell Transcriptomics Uncover a Novel Role of Myeloid Cells and T-lymphocytes in the Fibrotic Microenvironment in Peyronie's Disease

BACKGROUND

Peyronie's disease (PD) is an acquired fibrotic disease affecting the penile tunica albuginea that can lead to curvature and deformities, shortening, and erectile dysfunction. Although immunological mechanisms have been suggested for the pathophysiology of PD, these have not been investigated using single-cell transcriptomics.

OBJECTIVE

To investigate the immunological signature of plaques from PD patients using immunohistochemistry (IHC) and single-cell RNA sequencing (scRNA-Seq).

DESIGN, SETTING, AND PARTICIPANTS

Tunica albuginea biopsy was performed in patients undergoing penile surgery for either PD (n = 12) or plication or penile cancer (control, n = 6). The inclusion criteria for PD patients were stable chronic disease (≥12 mo in duration) and no previous penile surgery or intralesional injection therapy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

IHC was performed on surgical samples from ten patients with PD and five control subjects. An additional two PD and one control sample were used for scRNA-Seq (droplet-based; 10X Genomics). Cell clusters were visualised using heatmaps and t-distributed stochastic neighbour embedding plots (BioTuring v2.7.5).

RESULTS AND LIMITATIONS

IHC revealed the presence of myeloid dendritic cells (DCs; CD68⁺, TLR4⁺, CD206⁺), cytotoxic T lymphocytes (CTLs; CD3⁺, CD8⁺), and B lymphocytes (CD20⁺) in PD plaques, which were absent in controls. scRNA-Seq yielded results for 3312 PD and 5658 control cells. Cell clusters contained fibroblasts (COL1A2⁺), myofibroblasts (COL1A2⁺, ACTA2⁺), smooth muscle cells (ACTA2⁺, DES⁺), endothelial cells (VWF⁺), myeloid cells (CD14⁺), T lymphocytes (CD3D⁺), and neutrophils (ALPL⁺). Myeloid cell subclustering showed infiltration of monocyte-derived cells; control tissue contained classical DCs and resident macrophages. Lymphocyte subclustering revealed mucosal-associated invariant T (MAIT) cells and CTLs in PD. Differential gene expression suggests an increase in inflammatory and immune responses in chronic PD. The study is limited by the small scRNA-seq sample size (n = 3) for IHC, mitigated by a larger cohort of historic paraffin-embedded samples (n = 15), which showed largely parallel findings. Owing to tissue stiffness and extracellular matrix adhesion, our single-cell yield was lower for PD than for the control sample.

CONCLUSIONS

Our data suggest that even in the chronic PD stage (painless and stable curvature) there is a sustained inflammatory reaction. While vascularisation and collagen production are elevated, the inflammation is driven by specialised monocyte-derived CTL and MAIT cells. These findings could uncover new avenues for medical treatment of PD.

PATIENT SUMMARY

We looked at the role of the immune system in patients suffering from Peyronie's disease, a condition causing shortening and curvature of the penis. We found that even in a stable, chronic stage of the disease, there is activation of the immune system. Our results suggest that there is potential for novel treatments for this condition.

Efficacy and safety of collagenase Clostridium histolyticum in Peyronie's disease following a modified treatment protocol

INTRODUCTION

Collagenase Clostridium histolyticum (CCH) is the only approved treatment for conservative management of Peyronie's disease (PD) that has demonstrated efficacy and safety in clinical trials. However, as the standard treatment protocol is time and resource consuming, we are introducing a new CCH treatment protocol with a more cost-effective profile. Our goal is to evaluate its efficacy and safety.

MATERIALS AND METHODS

We included patients with PD in stable phase, with curvatures of 30-90degrees. Ventral curvatures and complex deformities were excluded. The treatment protocol consists of a full dose of CCH injected along the PD plaque, forming two lines of four injections. Patients were educated in daily penile modeling activities. The need for a new treatment cycle, up to a maximum of 8 cycles or until the 30-degree curve was decreased, was reevaluated every 4weeks. Changes in curvature and number of cycles were recorded to evaluate the efficacy. Regarding safety evaluation, treatment-related adverse events (TRAEs) were recorded, including rupture of the corpora cavernosa, penile hematoma, hematuria, and local infection.

RESULTS

Thirty-one patients were treated under the modified protocol. The mean initial curvature was of 49.84 (±15.83) degrees. Curvature improvement was recorded in 25 patients (80.6%), with a mean absolute reduction of 20.65 (±15.42) degrees and relative reduction of 44%. The mean curvature after treatment was 30.67 (±17.25) degrees. Most patients required one (19.4%) or two (54.8%) injections. No patient presented TRAEs.

CONCLUSIONS

The results suggest that the modified CCH treatment protocol is effective and safe, but more studies should be carried out to optimize the current standard protocol.

Outcomes of RestoreX Penile Traction Therapy in Men With Peyronie's Disease: Results From Open Label and Follow-up Phases

BACKGROUND

A randomized, controlled clinical trial evaluating the efficacy of RestoreX traction therapy in men with Peyronie's disease (PD) has been completed, with the 3-month results previously reported. The present study presents outcomes from the open-label and follow-up phases of the original trial.

AIM

To report 6-month (open-label phase) and 9-month (follow-up phase) outcomes from a randomized, controlled trial (NCT03389854).

METHODS

A randomized controlled trial was performed from 2017 to 2019 in 110 all-comer men with PD. Men were randomized 3:1 to RestoreX (PTT) or no therapy (control) for 3 months, followed by 3-month open-label and follow-up phases. Key outcomes included adverse events (AEs), changes in penile curvature and length, erectile function, and standardized and nonstandardized assessments of PD.

OUTCOMES

The primary outcomes are safety, penile length, penile curvature, Peyronie's Disease Questionnaire, International Index of Erectile Function, and satisfaction.

RESULTS

6-month (n = 64) and 9-month (n = 63) outcomes were reported, with a mean duration of PTT use of 31.1 minutes. No significant AEs were reported, with temporary erythema and discomfort being most common and resolving within minutes. On intent-to-treat analysis, control-to-PTT men experienced significant length (1.7-2.0 cm) and curvature improvements (18-20%). PTT-to-PTT men also achieved additional length (0.6-0.8 cm) without further curvature improvements. An as-treated analysis of PTT use ≥15 minute/day demonstrated 2.0- to 2.3-cm length gains (largest of any PTT to date) and 18-21% curve improvement. All sexual function domains of the International Index of Erectile Function and Peyronie's Disease Questionnaire were significantly improved (except orgasmic domain). 95% of men treated for 6 months experienced length gains (mean 2.0-2.2 cm), and 61% had curve improvements (16.8-21.4° [32.8-35.8%]). RestoreX was preferred 3-4:1 over all other PD treatments, and 100% preferred it over other PTT devices.

CLINICAL IMPLICATIONS

Use of RestoreX 30 minutes daily results in significant length and curve improvements in PD men without significant AEs.

STRENGTHS & LIMITATIONS

Strengths include largest randomized study of PTT, blinded assessments, and inclusion of all-comers with few restrictions; limitations include sample size that precludes comparisons between treatment cohorts and lack of long-duration (>3-9 hours) treatment arm.

CONCLUSION

PTT with RestoreX results in significant improvements in length, curve, and subjective and objective measures of sexual function without significant AEs. RestoreX PTT represents a safe, conservative, low-cost option for managing men with PD. Joseph J, Ziegelmann M, Alom M, et al. Outcomes of RestoreX Penile Traction Therapy in Men With Peyronie's Disease: Results From Open Label and Follow-up Phases. J Sex Med 2020;17:2462-2471.

Is Kelami's Method Still Useful in the Smartphone Era? The Virtual 3-Dimensional Reconstruction of Penile Curvature in Patients With Peyronie's Disease: A Pilot Study

BACKGROUND

Peyronie's disease is an idiopathic fibrotic disease affecting the penile tunica albuginea. Among other resulting deformities, the more common penile curvature should be assessed preferentially with in-office goniometric estimation after pharmacologically induced erection, although clearly invasive and uncomfortable.

AIM

In the present pilot study, we investigated the usefulness for the patient and the surgeon of a 3-dimensional (3D) reconstruction of the penile curvature obtained through photogrammetry software in clinical evaluation and surgical planning.

METHODS

Enrolled patients received alprostadil 10 μg by intracavernous injection. Then, the medical personnel took a sequence of up to 50 photographs in orthostatism via a smartphone and processed them to obtain a 3D model of the whole groin area with 3DF Zephyr free software (3Dflow SRL, Verona, Italy), to take measurements of the penile curvature with MeshLab software (National Research Council of Italy, Rome, Italy) and to simulate the results after corporoplasty with Blender software (Blender Foundation, Amsterdam, the Netherlands). Finally, we submitted a 1-5 Likert scale to patients and surgeons investigating their satisfaction with the use of the 3D model during preoperative counseling, surgical planning, and the esthetic results after surgery.

OUTCOMES

We investigated the patient and surgeon satisfaction with the use of the 3D model in understanding/evaluating the pathology and the surgical planning during the preoperative visit and the satisfaction with the final esthetic results in relation to the preoperative model itself.

RESULTS

4 patients were included. The median photographs acquisition and computer processing time were 39 seconds and 347.5 minutes, respectively. All the patients and surgeons involved gave a score of ≥4 to all the items investigated.

CLINICAL IMPLICATIONS

The 3D model of the penile curvature is very useful both to the patient and the surgeon to understand the severity of the disease and the possible surgical management.

STRENGTH & LIMITATIONS

This is a pilot study including only 4 cases, but it is the first experience in which the patients with Peyronie's disease had the possibility to see a virtual 3D model of their penile curvature and final esthetic results after corporoplasty, based on 3 freely available computer applications.

CONCLUSION

Our pilot study has shown that it is possible to quickly obtain a sequence of photographs to create an accurate virtual 3D model of the penis of patients with Peyronie's disease, helping the patients and the surgeon during preoperative counseling and surgical planning. Pavone C, Abrate A, Altomare S, et al. Is Kelami's Method Still Useful in the Smartphone Era? The Virtual 3-Dimensional Reconstruction of Penile Curvature in Patients With Peyronie's Disease: A Pilot Study. J Sex Med 2021;18:209-214.

Peyronie's disease: new paradigm for the treatment of a unique cause of erectile dysfunction

Peyronie's Disease is an incurable condition of the tunica albuginea of the penis associated with scarring, plaque formation, and penile deformity on erection. It is often associated with erectile dysfunction. Recent data have supported a familial and genetic predisposition to this chronic condition. The etiology of Peyronie's Disease is unknown, but is likely associated with multiple micro traumas to the erect penis in men who are susceptible to the scarring typical of Peyronie's Disease. The treatment of Peyronie's Disease has improved over the past decade as a result of animal studies and the approval of new medications. In the acute phase of the condition, phosphodiesterase type 5 inhibitors have been shown to have some benefit and are supported by animal studies demonstrating reduced fibrosis of the penis in animal models of Peyronie's Disease. In the stable phase of the disease, newer injectable agents have shown great promise. Collagenase clostridium histolyticum is approved for the treatment of Peyronie's plaques by direct injection into the scarred tissue with data showing satisfactory safety and efficacy. Surgical procedures for penile straightening have been refined with improved outcomes in the past decade. For those men with erectile dysfunction and Peyronie's Disease, penile implants can restore erectile function and form. As a result of the new understanding of the risk factors for Peyronie's Disease and recent advances in treatment options, the algorithm for the treatment of Peyronie's Disease has improved outcomes for patients and their partners.

Levels of serum trace elements in patients with Peyronie

Aim: The etiology of the disease of Peyronie is not certainly known. However, penile micro traumas are thought to be important in the pathogenesis of Peyronie's disease (PD) in genetically predisposed individuals. In this study, we aimed to determine the relationship of some trace element and heavy metals with PD.Material and methods: Thirty Peyronie patients and 26 healthy volunteers were included in the study. In individuals in both groups, levels of serum trace elements (Manganese [Mn], Cu, Cobalt (Co), zinc [Zn], Cd, and iron [Fe]) were determined separately by Atomic Absorption Spectrophotometer method in Yüzüncü Yıl University Central Research Laboratory.Results: Mn, Cu, Zn, and Fe levels in Peyronie patients were statistically significantly lower when compared to the healthy control group (p < .05). Cd and Co levels were similar for both groups but not statistically significant (p > .05).Conclusions: The changes in trace element levels are related to the etiopathogenesis of PD. We think that our study is the first from this aspect.

Phosphodiesterase Type 5 Inhibitors and Selective Estrogen Receptor Modulators Can Prevent But Not Reverse Myofibroblast Transformation in Peyronie's Disease

BACKGROUND

Myofibroblast transformation is a key step in the pathogenesis of Peyronie's disease (PD). Phosphodiesterase type 5 inhibitors (PDE5is) and selective estrogen receptor modulators (SERMs) can prevent the formation of fibrosis in in vitro and in vivo models of PD. However, it is unknown whether these drugs can also reverse established fibrosis.

AIM

To investigate whether PDE5is and SERMs can reverse transforming growth factor beta 1 (TGF-β1)-induced myofibroblast transformation and determine the point of no return.

METHODS

In-Cell enzyme-linked immunosorbent assay was used to quantify TGF-β1-induced myofibroblast transformation of human primary fibroblasts isolated from tunica albuginea (TA) of patients undergoing surgery for treatment of PD. Extracellular matrix production and collagen contraction assays were used as secondary assays. Reverse transcription-quantitative polymerase chain reaction and In-Cell enzyme-linked immunosorbent assay were used to measure drug target expression. PDE5i (vardenafil) and SERM (tamoxifen) were applied at various time points after TGF-β1.

OUTCOMES

Reversibility of myofibroblast transformation and drug target expression were investigated in a time-dependent manner in TA-derived fibroblasts.

RESULTS

Vardenafil or tamoxifen could not reverse the myofibroblast traits of alpha-smooth muscle actin expression and extracellular matrix production, whereas only tamoxifen affected collagen contraction after 72 hours of TGF-β1 treatment. Phosphodiesterase 5A and estrogen receptor (ER)-β were downregulated after 72 hours, and estrogen receptor -α protein could not be quantified. Tamoxifen could prevent myofibroblast transformation until 36 hours after TGF-β1 treatment, whereas vardenafil could prevent only 24 hours after TGF-β1 treatment. This was mirrored by downregulation of drug targets on mRNA and protein level. Furthermore, antifibrotic signaling pathways, peroxisome proliferator-activated receptor gamma and betaglycan (TGFB receptor III), were significantly downregulated after 36 hours of TGF-β1 exposure, as opposed to upregulation of profibrotic thrombospondin-1 at the same time point.

CLINICAL TRANSLATION

This study suggests that using PDE5is and SERMs might only help for early-phase PD and further highlights the need to test drugs at the appropriate stage of the disease based on their mechanism of action.

STRENGTHS & LIMITATIONS

The study uses primary human TA-derived fibroblasts that enhances translatability of the results. Limitations include that only 1 example of PDE5i- and SERM-type drug was tested. Time course experiments were only performed for marker expression experiments and not for functional assays.

CONCLUSION

This is the first study to demonstrate that timing for administration of drugs affecting myofibroblast transformation appears to be vital in in vitro models of PD, where 36 hours of TGF-β1 treatment can be suggested as a "point of no return" for myofibroblast transformation. Ilg MM, Stafford SJ, Mateus M, et al. Phosphodiesterase Type 5 Inhibitors and Selective Estrogen Receptor Modulators Can Prevent But Not Reverse Myofibroblast Transformation in Peyronie's Disease. J Sex Med 2020;17:1848-1864.

A state-of-art review on collagenase Clostridium Histolyticum and Peyronie's disease: drug profile, clinical evidence and safety outcomes

Introduction: Collagenase clostridium histolyticum (CCH) is the first and only licensed medical treatment for men with Peyronie's disease (PD). Published literature shows intralesional CCH injection as an effective and safe minimally invasive treatment in a specific subgroup of PD patients.Areas covered: The authors discuss pharmacodynamics and pharmacokinetics as well as clinical outcomes and safety profile from major CCH studies in PD. All relevant CCH studies published in PubMed and EMBASE databases up to June 2019 were included.Expert opinion: Given the variability in treatment schedule and drug access coupled with the potential need for further treatment, strict patient selection and the use of adjunctive strategies are key determinants to maximize clinical efficacy of intralesional CCH. Furthermore, longer-term follow-up data on the clinical outcomes, safety and durability of CCH in larger multi-center studies and post-marketing surveillance data are necessary to provide a comparison to other standard PD treatment options.

Comparison of male reproductive parameters in mice with type 1 and type 2 diabetes

OBJECTIVE

The differences between type 1 and type 2 diabetes mellitus (T1DM and T2DM) in terms of their adverse effects on male reproductive parameters have never been elucidated. This study aimed to distinguish between the effects of the DM types in mice treated with multiple low doses of streptozotocin (STZ) to mimic human T1DM and coadministered a high-fat diet (HFD) to mimic human T2DM.

METHODS

The T1DM mice were intraperitoneally injected with STZ (40 mg/kg body weight) for 5 days. The T2DM mice received an HFD for 14 days prior to STZ injection (85 mg/kg body weight), followed by continuous feeding of an HFD. Male reproductive parameters were evaluated.

RESULTS

The reproductive organs of the DM mice weighed significantly less than those of controls, and the seminal vesicles plus prostates of the T1DM mice weighed less than those of the T2DM mice. Increased sperm abnormalities and incomplete DNA packaging were observed in the DM groups. Sperm concentration and the proportion of normal sperm were significantly lower in the T1DM group. The seminiferous histopathology of DM mice was classified into seven types. The penises of the DM mice were smaller than those of the controls; however, tunica albuginea thickness and the amount of penile collagen fibers were increased in these mice. Round germ cells were abundant in the epididymal lumens of the mice with DM.

CONCLUSION

T1DM adversely affected reproductive parameters to a greater extent than T2DM.

Evolving therapies for Peyronie's disease: how can we work towards new drugs?

Peyronie’s disease (PD) is an idiopathic chronic fibrotic disease that causes a penile curvature (PC), subsequent erectile dysfunction (ED) and impaired sexual intercourse in patients. As of yet, there are no reliable non-surgical treatment options available. Intralesional injection with collagenase Clostridum Histolyticum has been FDA approved since 2013, but post-approval studies have not been unanimously positive. Moreover, it renders a curvature improvement of only 30% on average, usually still requiring surgical intervention to remedy PC. Therefore, there is a need for drugs which could prevent surgery altogether. Development of new drugs can either be through a target-based or phenotypic assay-based approach. The current in vivo model for PD is dependent on treatment of primary PD-derived fibroblasts with transforming growth factor-β1. Moreover, despite the existence of a genetic in vivo PD model, it does not allow for drug screening or testing. While some advances have been made in the past few years, new in vivo and in vivo systems and well-designed studies are urgently needed for the non-surgical treatment of PD.

Thrombospondin-1: A Key Protein That Induces Fibrosis in Diabetic Complications

Fibrosis accompanies most common pathophysiological features of diabetes complications in different organs. It is characterized by an excessive accumulation of extracellular matrix (ECM) components, the response to which contributes to inevitable organ injury. The extracellular protein thrombospondin-1 (TSP-1), a kind of extracellular glycoprotein, is upregulated by the increased activity of some transcription factors and results in fibrosis by activating multiple pathways in diabetes. The results of studies from our team and other colleagues indicate that TSP-1 is associated with the pathological process leading to diabetic complications and is considered to be the most important factor in fibrosis. This review summarizes the molecular mechanism of increased TSP-1 induced by hyperglycemia and the role of TSP-1 in fibrosis during the development of diabetes complications.

Intraoperative methods for residual curvature correction during penile prosthesis implantation in patients with Peyronie's disease and refractory erectile dysfunction

Peyronie's disease, or fibrous transformations of the tunica albuginea of the corpora cavernosa that cause penile curvature, is estimated to affect 3.2-8.9% of the male population. Treatment options for PD are based on the severity of the penile deformity and erectile function; of which surgical options include manual modeling during penile prosthesis implantation, plication, plaque incision, and grafting. Multiple approaches may be employed; each with its own advantages, limitations, and risk/benefit ratios. In this regard, we sought to review and highlight the current approaches for the management of residual curvature, optimal patient selection, and preoperative planning.

Verapamil and collagenase differentially affect collagen metabolism in experimental model of Peyronie's disease

OBJECTIVES

Peyronie's disease (PD) is accompanied by remodelling of connective tissue into fibrotic plaque. Treatment of the inflammatory and fibrotic phases of the disease is not established. The aim of the study was to evaluate the effect of verapamil (VER) and bacterial collagenase (COLL) on collagen metabolism and cell migration in fibroblasts with experimental wound healing and inflammation as an in vitro model of PD.

MATERIALS AND METHODS

In vitro model of PD was designed using experimental model of inflammation induced by Interleukin-1 (IL-1) in cultured fibroblasts and mechanical damage of the cells. Cell viability, cell proliferation, collagen biosynthesis, prolidase activity and cell migration were studied in both models of the cells treated with VER and COLL.

RESULTS

VER decreased cell viability, DNA and collagen biosynthesis and increased prolidase activity in control fibroblast, while in "wounded" fibroblasts it significantly decreased all the processes. COLL did not affect cell viability and DNA biosynthesis, while inhibited collagen biosynthesis and prolidase activity in both control and "wounded" fibroblasts. In IL-1-treated fibroblasts VER inhibited all studied processes except prolidase activity, while COLL inhibited only collagen biosynthesis and prolidase activity. COLL accelerated cell migration, while VER attenuated the process in fibroblast model of wound healing, compared to control cells.

CONCLUSION

VER and COLL attenuate collagen biosynthesis in both fibroblast models. The VER-dependent inhibition of collagen biosynthesis was accompanied by inhibition of DNA biosynthesis at high prolidase activity, while COLL affected this process through inhibition of prolidase activity at high rate of DNA biosynthesis. It shows that anti-fibrotic activity of VER/COLL and anti-inflammatory activity of VER may represent approach to establish standard treatment of PD.

Antioxidant Mechanism of Xiaojin Pill () for Treatment of Peyronie's Disease in Rats Based on Matrix Metalloproteinases

OBJECTIVE

To evaluate the effects of Xiaojin Pill () in the treatment of Peyronie's disease (PD) in a rat model.

METHODS

Twenty-four male Sprague-Dawley rats were randomly divided into four groups with 6 in each: sham operation, PD model, vehicle control and Xiaojin Pill groups. The rats in the sham operation group received penile tunica albsginea (TA) injection with 50 μL vehicle, while the rats in the other 3 groups received 50 μL penile TA injection of 50 μg transforming growth factor (TGF)-β1. Forty-two days after the injection, rats in the vehicle control and Xiaojin Pill groups received 0.5 mL water and Xiaojin Pill solution (107 mg/kg of body weight), respectively by gavage for 28 days, while those in the sham operation and PD model groups did not receive any intervention. After intervention, the expressions of matrix metalloproteinase 2/9 (MMP2/9), nitric oxidesynthase (NOS), superoxide dismutase (SOD) and malondialdehyde (MDA) were measured.

RESULTS

Rats in the PD model and vehicle control groups presented obvious fibrosis in corpus cavernosum (CC) and demonstrated a significantly increased expressions of MMP2 and MMP9 in the CC compared with the sham operation group (all P<0.01). In contrast, the expressions of MMP2 and MMP9 in the Xiaojin Pill group were significantly down-regulated (both P<0.01). In addition, the levels of NOS and MDA in CC were significantly increased while the activity of SOD was decreased in the PD model and vehicle control groups compared with the sham operation group (all P<0.01). After Xiaojin Pill treatment, the levels of MDA, NOS and SOD appeared to be corrected (all P<0.01).

CONCLUSIONS

Xiaojin Pill could reduce fibrosis in the CC by decreasing the expressions of MMPs, NOS and MDA, and by increasing the activity of SOD. Therefore, Xiaojin Pill might be a therapeutic option for PD.

Increased Risk of Cancer in Men With Peyronie's Disease: A Cohort Study Using a Large United States Insurance Claims Database

Background

Men with Peyronie’s disease (PD) may have an increased prevalence of certain comorbidities, including malignancy. We sought to examine the clinical relationship between PD and subsequent diagnosis of malignancy.

Methods

Using data from the IBM Health MarketScan claims database from 2007 to 2013, we compared men with PD to a control group of men without PD or erectile dysfunction matched for age and duration of follow-up. We compared incidence of 18 categories of malignancy between both groups using a Cox regression model.

Results

In total, 48,423 men with PD and 484,230 controls were identified. The mean age within both cohorts was 50 ± 9.4 years old, and mean follow-up time was approximately 4.4 ± 2.1 years. After being controlled for age, year of evaluation, obesity, smoking, number of outpatient visits, number of urologist visits, and duration of follow-up, men with PD had an increased risk of all cancers (hazard ratio = 1.10, 95% CI = 1.06–1.14), stomach cancer (1.43, 1.06–1.14), testis cancer (1.39, 1.05–1.84), and melanoma (1.19, 1.02–1.38) when compared with controls. The strengths in using the MarketScan database are the anonymous nature of the data, accessibility, and the power provided by the large number of patient visits recorded. Limitations include a lack of detail in certain facets of patient clinical data, and the lack of long-term follow-up to assess the impact of time on other potentially associated conditions.

Conclusions

This manuscript is the first to our knowledge to describe a relationship between PD and cancer. Men with PD may be at increased risk for certain malignancies compared with age-matched controls. Further investigation is needed to explore the clinical implications of these findings.

Pastuszak AW, Thirumavalavan N, Kohn TP, et al. Increased Cancer Risk in Men With Peyronie’s Disease: A Cohort Study Using a Large US Insurance Claims Database. Sex Med 2019;7:403–408.

The role of inflammatory parameters (neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and monocyte-to-eosinophil ratio) in patients with Peyronie's disease

OBJECTIVES

The aim of the study was to investigate the ability of the systemic inflammatory parameters to predict the discrimination of the phases of Peyronie's disease (PD).

MATERIALS AND METHODS

Demographic, clinical, and laboratory data from 156 patients with PD were analyzed. A complete blood count (CBC) was obtained for every patient, and the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-eosinophil ratio (MER) were calculated for every men. Subsequently, patients were divided into two groups based upon the phase of the disease.

RESULTS

The mean age was 51.9 ± 9.6 in all study population. The mean duration between symptom onset and patient evaluation was 4.2 ± 3.2 months in acute phase group, while it was 32.7 ± 31.7 months in chronic phase group (p < 0.001). There were no significant differences between the groups according to comorbidities such as diabetes, hypertension, lipid abnormalities, ischemic heart disease, smoking, and alcohol consumption. There was a statistically significant difference in NLR and PLR between two groups (p = 0.008, p = 0.008, respectively). NLR and PLR were significantly correlated with discrimination status in univariate analysis (p = 0.003, p = 0.005, respectively). Multivariate regression analysis revealed that NLR was the only independent risk factor for discrimination of the phases of PD (p < 0.001). The ROC analysis revealed a cutoff value of 1.8 (AUC 0.712, p < 0.001; sensitivity 61.1%; specificity 75.0%) for the NLR.

CONCLUSION

Our study demonstrated that NLR could be helpful to differentiate the chronic phase from the acute phase in patients with PD. Therefore, NLR could be used as an objective biomarker to the management of the disease and choosing the appropriate treatment.

Are Platelet Indices such as Platelet Volume, Platelet Distribution Width, and Plateletcrit Associated with Peyronie Disease?

PURPOSE

Peyronie disease (PD) occurs as a result of recurrent microvascular injuries or trauma of the tunica albuginea, although its precise etiology is unknown. Mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT), which are parameters indicative of platelet activity, are considered to be functional markers of platelets involved in the pathophysiology of related inflammatory and vascular diseases. In this study, we aimed to examine the relationship between PD and platelet indices.

MATERIALS AND METHODS

We evaluated participants who presented to the andrology department of our institution between December 2015 and May 2018. Ninety-two men with PD and 80 healthy volunteers were included in this study. Participants who had received medical treatment affecting platelets or had any hematologic or systemic diseases were excluded from the study.

RESULTS

The mean age of men with PD was 53.8±10.2 years, and the mean age of the control group was 52.2±8.0 years (p=0.465). There were no significant differences in the mean IIEF-5 scores, platelet count, MPV, PDW, or PCT between the patients with and without PD (p<0.05).

CONCLUSIONS

No correlations were found between PD and platelet indices. Large-scale prospective cross-sectional studies are needed to elucidate the etiopathogenesis of PD.

A review of inflammation and fibrosis: implications for the pathogenesis of Peyronie's disease

Peyronie's disease (PD) is a superficial fibrosing disorder that causes penile deformity and can interfere with sexual intercourse and reproduction, as well as diminish quality of life. While the exact mechanism of PD is still being investigated, there is likely a genetic component to the predisposition to penile plaque formation. Ultimately, however, perturbations in normal wound healing and aberrant deposition of extracellular matrix components lead to fibrotic tissue deposition. Fibrosis in PD is regulated by a complex pathway of inflammatory and fibrotic mediators. Currently there are no treatments for PD that address an underlying cause or disease progression. In this review, we provide an overview of the known inflammatory and fibrotic mediators of PD and explore the pathophysiology of other human superficial fibrosing disorders to develop further insights into 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 autologous adipose stromal vascular fraction reduces collagen III expression in a rat model of chronic penile fibrosis

Previous studies have shown that the injection of adipose stem cells and stromal vascular fraction(SVF) into the tunica albuginea (TA) during the inflammatory phase in a rat model of Peyronie's disease(PD) prevented the development of TA fibrosis. Our aim was to investigate whether local injection of SVF can reduce established fibrosis in a rat model of chronic phase of PD. Eighteen-male 12-wk-old Sprague-Dawley rats were divided in three equal groups: sham, PD without treatment (PD) and PD treated with SVF(PD-SVF). Sham rats underwent 2 injections of vehicle into the TA one month apart. PD rats underwent TGF-β1 injection and injection of vehicle one month later. PD-SVF rats underwent TGF-β1 injection followed by SVF (1-million cells) one month later. One month after the last treatment, the animals, n = 6 rats per group, underwent measurement of intracorporal and mean arterial pressure during electrostimulation of the cavernous nerve. Following euthanasia, penises were harvested for in-vitro study. Erectile function was not statistically significantly different between groups. PD animals developed subtunical areas of fibrosis and elastosis with upregulation of collagen III protein. These fibrotic changes were reversed after injection of SVF. We provide evidence that local injection of SVF reverses TA fibrosis in a rat model of chronic phase of PD.

Simvastatin and the Rho-kinase inhibitor Y-27632 prevent myofibroblast transformation in Peyronie's disease-derived fibroblasts via inhibition of YAP/TAZ nuclear translocation

OBJECTIVES

To uncover the anti-myofibroblast (MFB) properties of Rho-kinase inhibitor (compound Y-27632) and simvastatin in an in vitro model of Peyronie's disease (PD), a sexually debilitating disease caused by an irreversible fibrotic plaque in the penile tunica albuginea (TA).

MATERIALS AND METHODS

Primary human fibroblasts (FBs) were isolated from surgically obtained TA tissue from patients with PD. To induce MFB status, cells were stimulated with 3 ng/mL transforming growth factor-β1 (TGF-β1). Increasing doses of Y-27632 and simvastatin were added. Real-time quantitative PCR was used to assess mRNA expression of α-smooth muscle actin (α-SMA), collagen III, elastin and connective tissue growth factor (CTGF) after 72 h. Western blot analysis was used to quantify α-SMA protein contents, and immunofluorescence (IF) was used to visualize MFB differentiation by staining for α-SMA after 72 h. A resazurin-based assay was used to assess cell viability to ensure the anti-MFB effect of the drugs. A mechanistic study was performed using IF staining for YAP/TAZ nuclear translocation.

RESULTS

After 72 h of stimulation with TGF-β1, a six- to 10-fold upregulation of α-SMA could be observed. When treated with Y-27632 or simvastatin, the α-SMA, collagen III, elastin and CTGF mRNA expression was impeded. Additionally, TGF-β1 stimulation showed a twofold increase in α-SMA protein expression, which was reversed to non-stimulated levels after treatment with Y-27632 and simvastatin. Using IF, stimulated cells were identified as MFB (α-SMA+, Vim+) as opposed to the non-stimulated, Y-27632- and simvastatin-treated cells (α-SMA-, Vim+). The resazurin-based assay confirmed that the cell viability was not compromised by the administered drugs. On stimulation with TGF-β1, nuclear translocation of YAP/TAZ could be observed, which was prevented by adding the aforementioned compounds.

CONCLUSION

Transformation of FBs into the contractile and extracellular matrix-producing MFBs occurs after TGF-β1 stimulation. In our experiments, Rho-kinase inhibition and simvastatin treatment were shown to prevent this in TGF-β1-stimulated cells on an RNA and protein level through the inhibition of YAP/TAZ nuclear translocation. Y-27632 and simvastatin could become a novel treatment option in the early treatment of PD.

Review of Management Options for Active-Phase Peyronie's Disease

INTRODUCTION

Peyronie's disease (PD) is a fibrotic disorder that leads to plaque formation in ∼3-9% of adult men. Connective tissue buildup results in plaque formation, penile curvature and shortening, and in some cases, pain. In the active phase of PD, penile pain is a common symptom, often accompanied by progression in curvature. Treatment options for PD include oral drugs, topical cream, intralesional injections, traction, and shock wave therapy. This article reviews the different treatment options for active-phase PD.

AIM

To provide a comprehensive review of the current evidence-based treatments, focusing on active-phase PD.

METHODS

A PubMed database search was performed for studies on conservative therapy. We reviewed current clinical practices and trials for the treatment of active-phase PD and assessed their applicability as treatment options.

MAIN OUTCOME MEASURE

Define the most recent and effective therapies for the improvement in penile curvature in men presenting with acute PD.

RESULTS

A number of trials have resulted in significant benefits in the treatment of PD. Many of the oral therapies studied improved patient outcomes, but the data are insufficient. Similarly, there is no approved topical therapy by guidelines. The best options are intralesional injections of collagenase Clostridium histolyticum (CCh) and interferon-α2b. Shock wave therapy is not recommended for treatment of curvature, but has been shown to improve pain. Traction therapy may have a role in improving PD curve and penile length.

CONCLUSION

PD remains a challenge for urologists. Evidence suggests that, for oral therapy, a combination of drugs produces better results. Shock wave therapy is still unproven. Intralesional therapy delivers the best evidence for improvement in the active phase. CCh is the only FDA-approved treatment option available. Penile traction therapy may improve patient outcomes. Brimley SC, Yafi FA, Greenberg J, et al. Review of Management Options for Active-Phase Peyronie's Disease. Sex Med Rev 2019;7:329-337.

Advances in stem cell therapy for erectile dysfunction

INTRODUCTION

Stem cell (SC) application is a promising area of research in regenerative medicine, with the potential to treat, prevent, and cure disease. In recent years, the number of studies focusing on SCs for the treatment of erectile dysfunction (ED) and other sexual dysfunctions has increased significantly.

AREAS COVERED

This review includes critical ED targets and preclinical studies, including the use of SCs and animal models in diabetes, aging, cavernous nerve injury, and Peyronie's disease. A literature search was performed on PubMed for English articles.

EXPERT OPINION

Combination treatment offers better results than monotherapy to improve pathological changes in diabetic ED. Regenerative medicine is a promising approach for the maintenance of sexual health and erectile function later in life. Cavernous nerve regeneration and vascular recovery employing SC treatment may be focused on radical prostatectomy-induced ED. Notwithstanding, there are a number of hurdles to overcome before SC-based therapies for ED are considered in clinical settings. Paracrine action, not cellular differentiation, appears to be the principal mechanism of action underlying SC treatment of ED. Intracavernosal injection of a single SC type should be the choice protocol for future clinical trials.

The two phases of the clinical validation of preclinical translational mechanistic research on PDE5 inhibitors since Viagra's advent. A personal perspective

The FDA approval of Viagra (sildenafil) for the on demand treatment of erectile dysfunction (ED) through relaxation of the corporal and cavernosal vascular smooth muscle that results in an increase in blood flow to the corporal tissues stemmed from 2 decades of research, mainly at academic centers. This culminated in the finding of the nitric oxide/cGMP pathway as the mediator of penile erection, followed by some years of basic studies and clinical validation at Pfizer. Further on, new translational laboratory and animal research from our group initiated a second phase when we proposed an alternative therapeutic schedule and mechanism of action for PDE5 inhibitors (PDE5i) in both corporal veno-occlusive dysfunction (CVOD) and Peyronie's disease (PD), specifically, continuous long-term administration (CLTA) to achieve sustained levels of cGMP within the penis. Due to the extended half-life of the long-acting PDE5i, tadalafil, this new alternative encompasses preferentially daily administration, although shorter half-life PDE5i, like sildenafil and vardenafil work too, depending on the duration, dose, and frequency of their administration This novel use was initially supported by showing the antifibrotic/antioxidant effects of nitric oxide and cGMP, produced by the induction of iNOS, as a mechanism of defense against collagen deposition in the localized fibrotic plaque of PD in an avascular tissue, the tunica albuginea. Our studies on iNOS and the progressive diffuse fibrosis occurring in the smooth muscle in CVOD, led to proposing the CLTA of PDE5i for maintaining sustained cGMP levels both in PD and in CVOD in order to halt or regress the penile fibrosis. In CVOD, we showed that PDE5i protect the corporal smooth muscle and reduce myofibroblast activation and number, counteracting the underlying corporal tissue pathology that causes CVOD, and potentially ameliorating long-term CVOD or even curing it. This review is focused on this novel PDE5i anti-fibrotic therapeutic concept.