The effect of surgical trauma on rat tunica albuginea

MicroRNA-29b attenuates fibrosis in a rat model of Peyronie's disease

BACKGROUND

Peyronie's disease is characterized by the formation of fibrotic plaques in the penile tunica albuginea. Effective treatments are limited, warranting the investigation of new promising therapies, such as the application of microRNAs that regulate fibrosis-related genes.

OBJECTIVE

We aimed to investigate the therapeutic potential of mimicking microRNA-29b in a fibrin-induced rat model of Peyronie's disease.

MATERIAL/METHODS

The study was designed in two phases. To establish an optimal Peyronie's disease model, rats received either human fibrin and thrombin or saline solutions into the tunica albuginea on days 0 and 5. The animal model validation was done through expression and histopathological analyses, the latest by an experienced uropathologist. After validation, we performed microRNA-29b treatment on days 14, 21, and 28 of the study. This phase had control (normal saline) and scramble (microRNA scramble) groups. The mid-penile shaft was removed on day 30 for histological examination and molecular analyses in both study stages.

RESULTS

The control group displayed typical tunica albuginea histologic architecture in the animal model validation. In Peyronie's disease group, the Hematoxylin and eosin and Masson Trichrome staining methods demonstrated an interstitial inflammatory process with concomitant dense fibrotic plaques as well as disarrangement of collagen fibers. Additionally, we found out that reduced microRNA-29b (p = 0.05) was associated with significantly increased COL1A1 and transforming growth factor β1 genes and proteins (p > 0.05) in the Peyronie's disease group. After treatment with mimic microRNA-29b stimulation, the Hematoxylin & eosin and Masson Trichrome staining revealed a discrete and less dense fibrotic plaque. This result was associated with significantly decreasing expression of COL1A1, COL3A1, and transforming growth factor β1 genes and proteins (p < 0.05).

DISCUSSION

The fibrin-induced animal model showed significant histopathological and molecular changes compared to the Control group, suggesting that our model was appropriate. Previous findings have shown that increased expression of microRNA-29b was associated with decreased pathological fibrosis. In the present study, treatment with microRNA-29b decreased the gene and protein expression of collagens and transforming growth factor β1. This study reveals the therapeutic potential for Peyronie's disease involving molecular targets.

CONCLUSION

MicroRNA-29b application on the rat's tunica albuginea attenuated fibrosis, arising as a novel potential strategy for Peyronie's disease management.

Role of adipose-derived stem cells in healing surgically induced trauma of the rat's tunica albuginea

Background

Injection of adipose-derived stem cells (ADSCs) into the injured tunica albuginea (TA) may prevent fibrosis, restore the balance between pro- and antifibrotic pathways, and potentially mitigate erectile dysfunction caused by abnormal TA healing.

Aim

To assess the potential role of ADSC injection on structural, ultrastructural, functional, and molecular changes in surgically induced trauma of the rat's TA.

Methods

Forty adult male albino Wistar rats were divided into 5 groups of 8 rats each: group 1, sham; group 2, injury to TA without treatment; group 3, injury to TA and suture repair; group 4, injury to TA and injection of ADSCs without suture repair; group 5, injury to TA followed by injection of ADSCs and suture repair.

Outcomes

After 6 weeks, all groups were subjected to functional, histologic, and ultrastructural examination and molecular expression of healing growth factors.

Results

The intracavernous pressure (ICP; mean ± SD) was 114 ± 2, 32 ± 2, 65 ± 2, 68 ± 2, and 111 ± 2 mm Hg in groups 1 to 5, respectively. There were significant differences in ICP between each of groups 3 to 5 and group 2 (P < .05), and groups 3 and 4 each had significant differences with group 1 (P < .05). No significant difference in ICP occurred between groups 3 and 4 (P > .05). There were significant histologic and ultrastructural alterations in tunical tissues from group 2; however, these changes were markedly less in group 5 in terms of lower levels of fibrotic changes, elastosis, and superior overall neuroendothelial expression. Groups 3 and 4 showed improved structural and ultrastructural parameters when compared with group 2. Group 5 demonstrated lower levels of transforming growth factor β1 and basic fibroblast growth factor expression.

Clinical Implications

This experimental model may encourage administration of ADSCs to prevent the deleterious effects of trauma to the TA.

Strengths and Limitations

Injecting ADSCs can improve the healing process and erectile dysfunction in a rat model following TA injury, and combining ADSC injection with surgical suturing resulted in superior outcomes. The main limitation was the absence of long-term ICP measurements and a longer follow-up period that may provide further insight into the chronic phase of the healing process.

Conclusion

ADSC injection may prevent structural, ultrastructural, functional, and molecular alterations in surgically induced trauma of the rat's TA and enhance the effect of tunical suturing after trauma.

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.

New in vivo model to assess macroscopic, histological, and molecular changes in Peyronie's disease

BACKGROUND

Peyronie's Disease (PD) is a connective tissue disorder that affects the tunica albuginea (TA) of the penis causing curvature and erectile dysfunction. The pathophysiology is not well understood and, for this reason, treatment options are limited.

OBJECTIVE

The aim of the present study is to analyze and compare whether single or multiple instillations of plasma in the TA of rats is capable of triggering macroscopic, histopathological, and molecular changes consistent with PD.

MATERIAL/METHODS

Fifty male Wistar rats were divided into four groups: Group 1: a single instillation of plasma in the TA; Group 2: a single instillation of distilled water in the TA; Group 3: four instillations of plasma in the TA (1x per week); and Group 4: four instillations of distilled water in the TA (1× per week). Forty-five days after the last instillation a manual inspection of the corpus cavernosum, a penile erection test and a penectomy were performed to obtain material for histopathological and molecular analysis.

RESULTS

It was observed that 31.25% of the rats that received repeated instillations of plasma presented penile curvature according to the erection test, while none of the rats from the control group or group with one instillation of plasma presented curvature. In the animals that received four instillations of plasma, the following differences were observed in relation to the control group: increase in fibrosis and the deposition of collagen I. The protein expression of heparanase (HPSE) and TGF-β increased in the groups that received a single or four instillations of plasma, and the protein expression of heparanase-2 (HPSE-2), metalloproteinases (MMP-2, MMP-9) and metalloproteinase inhibitor (TIMP-2) showed an increase in the group that received four instillations of plasma. There was a significant increase in the gene expression of HPSE, MMP-9, and TGF-β in the group that received four instillations of plasma. In the analysis of the glycosaminoglycans, an increase was observed in the secretion of galactosaminoglycans chondroitin sulfate and dermatan sulfate (CS/DS) in the group that received four instillations of plasma.

DISCUSSION

Previous studies have demonstrated increased protein expression. of HPSE, MMP-9 and TGF-β with instillation of blood in the TA; however, there was no increase in gene expression. In the present study, the increase in the expression of TGF-β with plasma instillations, proved to be more reliable. The two models with plasma (one or four instillations) demonstrated significant histopathological and molecular changes when compared to the control group. However, only in the group with four plasma instillations there was a macroscopic change. The idea is that repeatedly extravasation of TGF-β present in plasma of predisposed individuals acts as a trigger for the development and maintenance of changes in the extracellular matrix that perpetuate an anomalous inflammatory process present in PD.

CONCLUSION

The present study shows that the repeated instillation of plasma is a low cost in vivo model for the study of PD.

Supporting the role of penile trauma and micro-trauma in the etiology of Peyronie's disease. Prospective observational study using the electronic microscope to examine two types of plaques

OBJECTIVES

The etiopathogenesis of Peyronie's disease (PD) remains not clearly understood. The most accepted theory attributes the histological lesions of PD to the effects of trauma to the corpora cavernosum of the penis. The aim of our study is to verify whether similar histological features exist between these two tissues, providing new evidence in favor of the traumatic theory in the etiopathogenesis of Peyronie's disease.

MATERIALS AND METHODS

A prospective observational study was carried out at our institution from January 2013 to June 2018, involving patients having undergone surgery for PD and those with delayed surgery for penile trauma. Both excised PD and post-traumatic plaques were analyzed by blind pathologists with an 80kV potential acceleration electron microscope.

RESULTS

Five patients were identified with a post-traumatic plaque (Group 1) and therefore an equal number of PD patients were enrolled for Group 2. The ultrastructural characteristics of the two types of preparations were very similar. In all the samples we showed an inflammatory reaction of the structure of the tunica albuginea, a production of the disorganized extracellular matrix, a proliferation of inflammatory cells and fibroblasts. Furthermore, we have found an increase in the density and collagen deposits grouped in the extracellular space and within the fibroblasts.

CONCLUSIONS

These findings support the theory that attributes lesions and symptoms typical of PD to the effects of cavernous body trauma.

Recent advances in managing Peyronie's disease

Treating men with Peyronie's disease remains a challenging problem facing clinicians working across urology and sexual medicine fields. Patients can often be left disappointed by current treatment paradigms, and an overall lack of suitable molecular targets has limited the options for novel, effective medical therapy. Managing men with Peyronie's disease often involves careful counselling alongside multifaceted and possible combination treatments to help improve symptoms whilst ameliorating potential side effects of therapy. We review the latest medical literature and evidence in the contemporary management of Peyronie's disease.

Peyronie's Disease is common in poorly controlled diabetics but is not associated with the Metabolic Syndrome

Purpose:

The purpose of the study is to investigate if metabolic syndrome (MS) and other comorbidities are associated with Peyronie's disease (PD).

Methods:

A total of 1833 patients retrospectively investigated and divided into two groups: Group A – PD patients (n = 319) and Group B – non-PD patients (n = 1303). The two groups were fully evaluated for diabetes mellitus (DM) with the glycated hemoglobin (HbA1c), hypertension (HTN), dyslipidemia (DL), obesity by measuring body mass index, total testosterone (T), penile vascular circulation measuring Peak systolic velocity (PSV) as indicator of arterial supply, end-diastolic velocity (EDV) as indicator of venous output, and finally, smoking.

Results:

The presence of diabetes was significantly correlated with PD (P = 0.005). Patients with diabetes had a 7% higher incidence of PD. However, patients with the highest HbA1c level of >8.5 had an increased odds ratio of 1.6 (P = 0.025, confidence interval [CI] =1.061–2.459) of having PD. Increased age was significantly correlated with PD (P = 0.025). For each year of life, the likelihood of having PD increases by an odds ratio of 1.019, or 2% per year (P = 0.001, CI = 1.004–1.027). Unexpectedly, DL (P = 0.006) and smoking (P = 0.041) were associated with lower incidences of PD. Patients with DL or smoking had a 5%–7% lower incidence of PD with an odds ratio of 0.6 (P = 0.006, CI = 0.410–0.864). HTN (P = 0.621) and the total number of comorbidities (P = 0.436) were not correlated with PD. Mean serum T values were statistically (P = 0.43) but not clinically significant among patients with Peyronie's versus patients without Peyronie's (4.62 vs. 4.38 ng/ml). Neither low PSV (Fisher's exact test P = 0.912) nor abnormal EDV (Fisher's exact test P = 0.775) was correlated with the finding of PD.

Conclusions:

While MS was not associated with PD, diabetes, particularly poorly controlled diabetes, was associated with an increased rate. Further research into the interaction of PD and metabolic disease is warranted.

Adipose-derived Stem Cells Counteract Urethral Stricture Formation in Rats

BACKGROUND

A medical treatment for urethral stricture (US) is not yet available.

OBJECTIVE

To evaluate if local injection of human adipose tissue-derived stem cells (hADSC) prevents urethral fibrosis in a rat model of US.

DESIGN, SETTING, AND PARTICIPANTS

Male rats were divided into three groups: sham, US, and hADSC (n=12 each). Sham rats received a vehicle injection in the urethral wall. US and hADSCs were incised and injected with the fibrosis-inducer transforming growth factor-β1 in the urethral wall.

INTERVENTION

One day later, hADSCs were injected in the urethral wall of hADSC rats whereas sham and US rats were injected with the vehicle. After 4 wk, the rats underwent cystometries and tissues were then harvested for functional and molecular analyses.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Cystometry, microultrasound, histochemistry, organ bath studies, reverse transcription polymerase chain reaction, and western blot.

RESULTS AND LIMITATIONS

US rats exhibited 49-51% shorter micturition intervals, 35-51% smaller micturition volumes and bladder capacity, 33-62% higher threshold pressures and flow pressures, and 35-37% lower bladder filling compliance compared with hADSC-treated rats and sham rats (p<0.05). By ultrasound, US rats had hyperechogenic and thick urethral walls with narrowed lumen compared with sham rats, whereas hADSC rats displayed less extensive urethral changes. Isolated detrusor from US rats exhibited 34-55% smaller contractions than detrusor from sham rats (p<0.05). Corresponding values were 11-35% for isolated detrusors from hADSC rats. Collagen and elastin protein expression were increased in the penile urethras of US rats compared with sham and hADSC groups (p<0.05). Endothelial and inducible nitric oxide synthase expressions were higher (p<0.05) in the hADSC group. Compared with US rats, hADSC rats demonstrated decreased expression of several fibrosis-related genes. Administration of hADSCs was performed at an early stage of US development, which we consider a limitation of the study.

CONCLUSIONS

Local injection of hADSCs prevents stricture formation and urodynamic complications in a new rat model for US.

PATIENT SUMMARY

Stem cell therapy is effective for preventing urethral stricture in an experimental setting.

PEYRONIE'S DISEASE: A REVIEW OF ETIOLOGY, DIAGNOSIS, AND MANAGEMENT

Peyronie's Disease (PD) is a superficial fibrosing disorder of the penis resulting in plaque formation and penile deformity. Once considered rare, PD has more recently been found in up to 13% of men, and can negatively affect sexual and psychosocial function of both patients and their partners. While the etiology of PD is unclear, it is thought to result from an inciting traumatic event followed by aberrant fibrosis or dysregulated wound healing. The evaluation of men presenting with PD includes a detailed history and physical exam, focusing on the penis in both the flaccid and erect states. PD is often associated with erectile dysfunction (ED), as well as several other comorbidities. Laboratory testing is not needed to diagnose PD, although given the associations between PD and systemic diseases including hypogonadism, diabetes, and cardiovascular disease, screening and work-up for these conditions in men with PD may be warranted. Treatment modalities for PD are diverse and include oral, topical, intralesional, mechanical, and surgical therapies. Oral, topical, and mechanical therapies generally have little evidence supporting their efficacy. Several intralesional therapies, including interferon α2b and collagenase Clostridium hystiolyticum have demonstrated efficacy in the treatment of PD. Surgical treatment, indicated in men with significant, stable deformity, includes plication of the tunica albuginea, plaque incision/excision and grafting, and placement of inflatable penile prosthesis (IPP) with or without additional maneuvers to achieve desired results, and has high success rates.

The pathophysiology of Peyronie's disease

OBJECTIVE

To review the contemporary knowledge of the pathophysiology of Peyronie's disease (PD).

METHODS

Medline was searched for papers published in English from 2000 to March 2013, using the keywords 'Peyronie's disease' and 'pathophysiology'.

RESULTS

More than 300 relevant articles were identified for the purpose of this review. Unfortunately only a few studies had a high level of evidence, and the remaining studies were not controlled in their design. Many theories have been proposed to explain the cause of PD, but the true pathogenesis of PD remains an enigma. Identifying particular growth factors and the specific genes responsible for the induction of PD have been the ultimate goal of research over the past several decades. This would provide the means to devise a possible gene therapy for this devastating condition. We discuss present controversies and new discoveries related to the pathophysiology of this condition.

CONCLUSION

PD is one of the most puzzling diseases in urology. The pathogenesis remains uncertain and there is still controversy about the best management. The pathogenesis of PD has been explored in animal models, cell cultures and clinical trials, but the results have led to further questions. New research on the aetiology and pathogenesis of PD is needed, and which will hopefully improve the understanding and management for patients with this frustrating disease.

Rat as an animal model for Peyronie's disease research: a review of current methods and the peer-reviewed literature

While the exact mechanism of Peyronie's disease (PD) remains an enigma, the pathophysiology of PD is considered to be multifactorial, with interactions of genetic predisposition, trauma, tissue inflammation and aberrant wound healing. A non-systematic review of the existing English language literature pertaining to the use of rodent models in the evaluation of PD was performed using the Medline database. Multiple free-text searches were performed on key words: animal models of PD, transforming growth factor β1 (TGF β1), tunical and/or corporal fibrosis, subtunical injection and penile myofibroblasts. The most frequently reported models of PD can be classified as TGF β1, fibrin and surgical trauma-induced models. In vitro studies using Peyronie's fibroblast culture media have also provided further insights into cellular mechanism of PD. At the present time, the research in PD is hampered by the lack of universally accepted animal model and this is likely attributed to the limited insight into PD mechanisms and the difficulties faced by current animal models to truly represent the complexity and complete spectrum of human disease.

Relationship between penile fracture and Peyronie's disease: a prospective study

Peyronie's disease is postulated to be initiated by repetitive minor traumas to the fully or partially erect penis. We investigated Peyronie's disease prospectively in cases treated for penile fracture (PF) within the last 20 years. Medical records of 63 cases treated for PFs were reviewed. Subjects were required to self-assess their current penile morphologies and sexual functions. Penile nodules and Peyronie's plaques were also evaluated with physical examination, ultrasonography and magnetic resonance imaging (MRI), and penile curvatures with auto-photography, and sexual function with international erectile function index (IIEF). Of the 63 cases (mean age 37 years), 46 who had mean follow-up of 63 months were re-evaluated. The mean IIEF-5 score was 23.2±3.1. Painful erections (n=5), penile nodules (n=5) and also penile curvatures <20° (n=2) were investigated. No Peyronie's plaque was palpated in any of the cases. Ultrasound and MRI showed fibrotic nodules of 5 mm in diameter, which extended into the subtunical area in the rupture site in 54% of the cases, although any thickening and Peyronie's plaque were not found in the tunica albuginea and intracavernosal septum of the cases examined. In PF patients treated surgically, the erectile function and penile morphology were preserved. In our cases PFs did not induce the development of Peyronie's disease.

The management of Peyronie's disease: evidence-based 2010 guidelines

INTRODUCTION

The field of Peyronie's disease is evolving and there is need for a state-of-the-art information in this area.

AIM

To develop an evidence-based state-of-the-art consensus report on the management of Peyronie's disease.

METHODS

To provide state-of-the-art knowledge regarding the prevalence, etiology, medical and surgical management of Peyronie's Disease, representing the opinion of leading experts developed in a consensus process over a 2-year period.

MAIN OUTCOME MEASURES

Expert opinion was based on grading of evidence-based medical literature, widespread internal committee discussion, public presentation, and debate.

CONCLUSIONS

The real etiology of Peyronie's disease and the mechanisms of formation of the plaque still remain obscure. Although conservative management is obtaining a progressively larger consensus among the experts, surgical correction still remains the mainstay treatment for this condition.

Experimental models of Peyronie's disease. Implications for new therapies

INTRODUCTION

Despite its high prevalence and impact on the quality of life of patients, and that it is an excellent model for the study of fibrotic processes, Peyronie's disease (PD) is an orphan disease in biomedical research. The development of animal and cell culture models has advanced substantially the understanding of its molecular and cellular pathology and the proposal of new therapies.

AIM

To review the literature pertaining to the use of these models for the study of PD.

METHODS

PubMed search conducted from the first report of an animal model for PD.

RESULTS

This model, based on the finding that transforming growth factor beta1 (TGF beta 1) is overexpressed in the PD plaque, consists on the injection of TGF beta 1 into the tunica albuginea of the rat. This leads to a PD-like plaque retaining many of the histological and biochemical features of human PD. Another rat model, based on the hypothesis that the PD plaque arises from trauma to the penis, causing fibrinogen extravasation that initiates as fibrin a fibrotic response, consists on injection of fibrin into the tunica. The cell culture model is based on the demonstration that myofibroblasts are abundant in the human PD plaque.

CONCLUSIONS

These models have: (i) clarified the role of microtrauma, myofibroblasts, and oxidative stress in plaque development; (ii) demonstrated that this tissue is under sustained turnover by fibrotic and antifibrotic mechanisms; (iii) showed the interplay of collagenolytic and fibrinolytic systems and their inhibitors; (iv) detected an endogenous antifibrotic process consisting of the expression of inducible nitric oxide synthase that counteracts oxidative stress, collagen synthesis, and myofibroblast generation; (v) characterized the antifibrotic effects of chronic treatment with phosphodiesterase type 5 (PDE5) inhibitors; (vi) discovered the cytogenetic instability of PD cells and alterations in their gene expression; and (vii) detected stem cells in the tunica albuginea with a potential role in fibrosis and ossification.

Comparison of vitamin E and propionyl-L-carnitine, separately or in combination, in patients with early chronic Peyronie's disease: a double-blind, placebo controlled, randomized study

PURPOSE

We compared the efficacy and safety of oral vitamin E and propionyl-L-carnitine, separately or in combination, for the treatment of Peyronie's disease.

MATERIALS AND METHODS

A total of 236 men (mean age 43.4 years) with Peyronie's disease were randomly assigned to 4 groups. Group 1 (58 men) received 300 mg vitamin E orally twice daily. Group 2 (59) received 1 gm propionyl-L-carnitine orally twice daily, and group 3 (60) received 300 mg vitamin E and 1 gm propionyl-L-carnitine orally twice daily. Group 4 (control group, 59 men) received a similar regimen of placebo during the 6-month treatment period. The efficacy of the 4 treatments was assessed using responses to the International Index of Erectile Function, visual analog scale for pain evaluation, mean intercourse satisfaction domain, mean weekly coitus episodes, penile curvature, plaque size and adverse drug effects.

RESULTS

Pain decreased in 60.4%, 63%, 62.3% and 59.2% of the patients treated with vitamin E, propionyl-L-carnitine, vitamin E plus propionyl-L-carnitine and placebo, respectively (p = 0.1). After therapy a reduction in penile curvature was observed by 18.9%, 20.4%, 22.6% and 18.4% of the patients in groups 1, 2, 3 and 4, respectively (p = 0.09), and a decrease in plaque size was noted in 11.3%, 12.9%, 13.2% and 11.1%, respectively (p = 0.1).

CONCLUSIONS

This study did not show significant improvement in pain, curvature or plaque size in patients with PD treated with vitamin E, propionyl-L-carnitine, or vitamin E plus propionyl-L-carnitine compared with those treated with placebo.

Measurement of Penile Curvature in Peyronie’s Disease Patients: Comparison of Three Methods

AIM

Peyronie's disease (PD) may be treated in a medical or surgical fashion. Factors involved in the decision of which treatment to choose include duration of disease and magnitude of penile deformity. Curvature can be measured using at-home photography (AHP), vacuum erection device (VED), or intracavernosal injection (ICI). This study was undertaken to determine the concordance between the three methods of deformity assessment. Patients were also questioned regarding the presence of erectile dysfunction (ED) based on self-report and the International Index of Erectile Function.

MATERIALS AND METHODS

A total of 68 men presented to their urologist after taking penile photographs from three angles during maximal erectile rigidity. In the office, a VED was used to induce erection, and a goniometer was utilized to measure degree of curvature. ICI with trimix was then used to induce artificial erection, which was measured with a goniometer as well.

RESULTS

There was a statistically significant difference in self-report curvature magnitude compared with measured ICI-assisted curvature. Curvature profiles included dorsal plaques in 50 patients (73.5%), ventral plaques in 10 (15%), and lateral in eight (11%). Using ICI, the mean curvature measured was 42 degrees. Mean degree of curvature using VED was 33 degrees, while that of photography was 34 degrees. Photographic measurements differed most from ICI in men with concurrent ED (P < 0.01), while vacuum device measurements were most inaccurate in men with curvatures of >60 degrees.

CONCLUSIONS

Our results show that the degree of curvature measured using vacuum-assisted device and AHP is underestimated as compared with the gold standard ICI. We therefore recommend that ICI be used to most accurately determine degree of deformity. If ICI is not available, it is imperative that the same manner of measurement be used between all patients in a study group, as well as during serial evaluation in a trial.

Prevalence of Peyronie's disease among patients with erectile dysfunction

PURPOSE

To assess the prevalence of Peyronie's disease (PD) among patients with erectile dysfunction (ED).

MATERIALS AND METHODS

A total of 1,440 male patients with ED were enrolled in this study. Patients were interviewed for ED using the International Index of Erectile Function (IIEF). All patients were also screened for socio-demographic data and risk factors for ED that included age, smoking, diabetes, hypertension, dyslipidemia, Ischemic Heart Disease (IHD), and psychological disorders. The diagnosis of PD was based on a palpable penile plaque or acquired penile curvature. Patients underwent routine laboratory investigation in addition to testosterone and prolactin assessment.

RESULTS

Mean ages +/-SD were 54.1 +/- 6.9 (range 42-71) and 52.5 +/- 11.9 (range 20-84) years for patients with and without PD respectively. Of the patients, 11.8% had mild, 38.3% had moderate and 49.9% had severe ED. 7.9% of the patients had PD. Significant associations between PD and both the longer duration and the increased severity of ED were detected. There were also significant associations between PD and the following socio-demographic risk factors of ED: age, obesity, smoking, duration and number of cigarettes smoked per day. Concomitant diseases and medical comorbidities such as diabetes, dyslipidemia, psychological disorders and the presence of at least one risk factor were significantly associated with PD in patients with ED.

CONCLUSIONS

Peyronie's disease was not rare among the study population. There were significant associations between ED risk factors and PD. Further studies are needed to investigate how much ED and PD influence each other.

Intracavernosal prostaglandin E1 self vs office injection therapy in patients with erectile dysfunction

We have investigated the reliability of intracavernosal prostaglandin E1 (PGE1) office vs self-injection therapy in patients with erectile dysfunction (ED). A total of 298 male patients with ED were enrolled in this study. In all patients, intracavernosal titration of the PGE1 dose was performed. A total of 106 patients were enrolled in the self-injection program, and 192 patients were enrolled in the office injection program. There were significant differences between number of injections and amount of PGE1 per month, total number of injections, and total amount of PGE1 on office and self-injection programs (P < 0.05 for each). There was a significant increase in the dropout rate in the office injection group compared with the self-injection group (P < 0.05). There was an increase in penile fibrosis in the self-injection program compared with the office program (P < 0.05). A self-injection program is reliable. Office injection program can be reserved for a subset of ED patients with special preferences.

New discoveries in the basic science understanding of Peyronie’s disease

Peyronie's disease is an acquired benign condition representing localized fibrosis of the penis. The disease is caused by microvascular trauma to the penis, with subsequent fibrin deposition resulting in aberrant wound healing and possibly other etiologies. Histopathologic studies of the Peyronie's plaque have demonstrated the role of transforming growth factor-beta 1 in the pathologic development of penile plaque. Animal models have been developed to test pathophysiology and therapeutics. The role of inducible nitric oxide synthase and nitric oxide has been established to limit and counteract fibrosis. Differential gene expression studies have identified candidate up-regulated or down-regulated genes that are involved in the pathophysiology of Peyronie's disease.

Peyronie's disease: an update of the medical management

Peyronie's disease (PD) is characterised by penile plaque formation, pain, penile deformity and erectile dysfunction. It is a fibrotic disorder of the tunica albuginea with a poorly understood aetiology and epidemiology. PD may be classified into inflammatory (acute) and chronic stages. Medical treatment is usually instigated during the inflammatory phase of the disease. A review of the literature reveals a wide range of oral, intralesional and alternative therapies that are discussed in relation to established pathophysiological mechanisms of the disease. The advantages and disadvantages of each treatment are summarised. This review also discusses the ongoing therapeutic dilemmas of PD and suggests a treatment strategy based on an analysis of the urological literature.

Therapeutic effects of colchicine in the management of Peyronie's disease: a randomized double-blind, placebo-controlled study

To determine effectiveness and safety of colchicine in Peyronie's disease. In all, 84 patients with Peyronie's disease who did not have calcified plaque were entered into study. The mean disease duration was 15 months. A medical history was obtained, and physical examination, penile X-ray, and dynamic penile duplex ultrasound were performed. Patients were randomly divided into group 1, those who received 0.5-2.5 mg colchicine daily for 4 months and group 2, who received placebo for the same period. Response to therapy was assessed objectively, during dynamic penile duplex ultrasound, as well as subjectively using International Index of Erectile Function (IIEF) questionnaire and measurements of pain, duration of disease, penile curvature, and plaque size. Differences before and after treatment and among the three Kelami classification groups were assessed. In total, 78 (92.8%) completed the whole treatment schedule. Pain resolved in 60 and 63.6% of the patients treated with colchicine and placebo, respectively (P > 0.05). After therapy, in subjects and controls a reduction in the penile deformity was observed by 17.1 and 18.4% of the patients (P > 0.05), and a decrease in plaque size was noticed by 10.5 and 10%, respectively (P > 0.05). Objective measurements did not demonstrate any difference in plaque size or penile curvature. There were no substantial differences in response to treatment based on duration of disease or within the three Kelami classification groups. Significant drug-related adverse effects occurred in colchicine group and in two cases was treatment discontinued. Colchicine is no better than placebo in improvement of pain, curvature angle, or plaque size in patients with Peyronie's disease.

Peyronie's disease: a review

PURPOSE

We provide a current review of Peyronie's disease.

MATERIALS AND METHODS

We reviewed the world peer reviewed literature on the pathology, pathogenesis, diagnosis and treatment of Peyronie's disease.

RESULTS

The incidence of Peyronie's disease has continuously increased during the last 30 years. However, fewer patients need prosthesis surgery as the sole treatment option because of earlier diagnosis, improved medical therapy, refinement in surgical technique and better understanding of the basic sciences of the disease.

CONCLUSIONS

Currently patients with Peyronie's disease have had improvements in prognosis and experienced an expansion of the available therapeutic options.

Gene expression in Peyronie's disease

Currently, surgical intervention is the only efficacious treatment for Peyronie's disease (PD), a fibromatosis of the tunica albuginea of the penis. Therapies based on the molecular pathways for this disease could provide alternatives to surgical treatment but only recently has the pathophysiology of the Peyronie's disease plaque been investigated at the molecular level. In this review, we examine the current knowledge of gene expression in the PD plaque and the relationship of PD with other fibrotic conditions such as Dupytren's disease. TGFbeta1, along with other growth factors, pro-fibrotic genes, and collagen, are expressed in fibroblasts and myofibroblasts. Myofibroblasts are normally involved in wound contracture and largely eliminated via apoptosis during the late stages of wound remodeling. In the PD plaque, however, these cells persist and may play an important role in the PD plaque fibrosis. The expression levels of TGFbeta1 and pro- and anti-fibrotic gene products, along with the nitric oxide/reactive oxygen species (NO/ROS) ratio in the tunica albuginea, appear to be essential for the formation and progression of the PD plaque and effect the expression of multiple genes. This can be assessed with the recently developed DNA-based chip arrays and results with the PD plaque have been encouraging. OSF-1 (osteoblast recruitment), MCP-1 (macrophage recruitment), procollagenase IV (collagenase degradation), and other fibrotic genes have been identified as being possible candidate regulatory genes. Finally, possible therapeutic avenues for gene-based therapy in the treatment of PD are discussed that may eventually reduce the need for surgical intervention.

Implications of nitric oxide synthase isoforms in the pathophysiology of Peyronie's disease

Peyronie's disease is an idiopathic, localized connective tissue disorder of the penis which involves the tunica albuginea of the corpus cavernosum and the adjacent areolar space. Peyronie's disease is characterized by local changes in the collagen and elastic fiber composition of the tunica albuginea. The formation of fibrotic plaques alters penile anatomy and can cause different degrees of bending and narrowing, as well as penile pain and erectile dysfunction. Though long recognized as an important clinical entity of the male genitalia, the etiology of this disease has remained poorly understood. Until recently there have been no studies to examine the role nitric oxide (NO) and nitric oxide synthase (NOS) isoforms may play in the onset and progression of Peyronie's disease. NO is a potent biological mediator with diverse physiological and pathophysiological roles. The purpose of this review is to describe each of the NOS isoforms and their potential roles in the pathophysiology of Peyronie's disease, with particular emphasis on the regulation of endothelial and inducible NOS isoforms.

A retrospective review of 307 men with Peyronie's disease

PURPOSE

We discuss the clinical appearance and natural outcome of Peyronie's disease.

MATERIALS AND METHODS

During an 8-year period 307 men with Peyronie's disease were evaluated, and clinical characteristics, risk (factors), penile deformities, erectile status and outcome were analyzed.

RESULTS

Mean patient age plus or minus standard deviation was 52.8 +/- 9.3 years (range 23 to 76). Penile deformity, pain on erection and palpable nodule were the most common (85%) presenting symptoms, usually in different combinations. The remaining 15% of men (mean age 59.4 +/- 6.5 years) were not aware of the penile deformity and were diagnosed during standard evaluation for erectile dysfunction. Dorsal (45.6%) and lateral (29.3%) were the most common curvatures. The degree of deformity was less than 30 degrees in 42.7% of patients, 31 to 60 degrees in 38.8% and greater than 60 degrees in 18.6%. At least 1 risk factor for systemic vascular disease was identified in 67.5% of patients, and hypercholesterolemia and diabetes were the most common. Patients with at least 1 risk factor had a significantly higher risk for severe penile deformity. Of the men 54.4% complained of erectile dysfunction and the probability of diminished erectile capacity was 86.7% in patients older than 60 years, with Peyronie's disease for more than 12 months and at least 1 risk factor. Of 63 patients presenting with the acute phase of disease penile deformity deteriorated in 30.2%, did not change in 66.7% and resolved spontaneously in 3.2% without any treatment after a mean followup of 8.4 months.

CONCLUSIONS

Our data show that penile deformities are disabling (greater than 30 degrees) in 62.5% of cases. Risk factors, such as serum lipid abnormalities, diabetes and hypertension, seem to have significant impact on the severity of symptoms and outcome. Patients must be informed that Peyronie's disease is progressive in 30.2% without treatment and spontaneous resolution is rare.

Upregulation of monocyte chemoattractant protein 1 and effects of transforming growth factor-beta 1 in Peyronie's disease

Peyronie's disease (PD) is characterized by fibrosis in the tunica albuginea (TA) of the penis, which becomes bent as a result. We have previously shown that transforming growth factor-beta 1 (TGF-beta1) is upregulated in the TA of patients with PD and can initiate PD-like lesions in rat models. In this study we isolated three types of fibroblasts: P cells from the lesions of PD patients, C cells from the normal-appearing areas of the TA of the same patients, and N cells from the TA of patients without PD. We examined these cells for the expression of two fibrogenic cytokines, connective tissue growth factor (CTGF), and Monocyte Chemoattractant Protein 1 (MCP-1). We found that CTGF was expressed at similar levels in P, C, and N cells, whereas MCP-1 was significantly more expressed in P cells than in C cells and more in C cells than in N cells. Higher MCP-1 expression was also found in the lesions than in normal TA. Treatment with TGF-beta1-induced higher expression of MCP-1 but not CTGF in all three types of cells, with C cells being the most responsive. Based on these observations, we propose that MCP-1 could be a novel therapeutic target in PD.

Peyronie's disease: advances in basic science and pathophysiology

Peyronie's disease is an idiopathic, localized connective tissue disorder of the penis that involves the tunica albuginea of the corpus cavernosum and the adjacent areolar space. The tunica albuginea plays an important role in the mechanism of erection. Peyronie's disease is characterized by local changes in the collagen and elastic fiber composition of the tunica albuginea. The formation of fibrotic plaques alters penile anatomy and can cause different degrees of bending, narrowing, or shortening of the penis. Moreover, a significant number of men with Peyronie's disease develop erectile dysfunction. Penile blood flow studies in many patients with Peyronie's disease suggest a strong association with veno-occlusive dysfunction. Although long recognized as an important clinical entity of the male genitalia, the etiology of this disease has remained poorly understood. The following review focuses on recent research on the pathophysiology of Peyronie's disease.

New aspects in Peyronie's disease--a mini-review

There have been several advances in elucidation of the pathogenesis of Peyronie's disease. Transforming growth factor beta 1 seems to play a major role in this disease, while the importance of penile trauma is a matter of debate. High-resolution ultrasound sonography is the method of choice in detecting penile plaques, while magnetic resonance imaging is useful in the evaluation of actively inflamed plaques. There are still differences of opinion on the best drug therapy in noncalcified plaques. The results on tamoxifen or interferon therapy vary between useless and useful. Potassium-para-aminobenzoate seems to have a significant effect in decreasing plaque size and deviation angle. The operative strategy for big plaques or complex deviation has changed to the 'small incision' graft, leading to far lower post-operative impotence rates. Iontophoresis seems to be worthy of further trials, while the results of extracorporal shock wave therapy have to be discussed critically.

Penile fibrotic changes after radical retropubic prostatectomy

OBJECTIVE

To investigate the type of penile deformity, response to treatment of and predictive factors for the formation of penile fibrotic changes after radical retropubic prostatectomy (RRP).

PATIENTS AND METHODS

Between July 1996 and September 1998, 110 men who had undergone RRP a mean (SD, range) of 35 (20, 5-145) months previously were evaluated by one physician for their erectile dysfunction. Those men affected by penile fibrotic changes were advised to initiate medical therapy for possible Peyronie's disease; their charts were reviewed and they were interviewed to determine the outcome.

RESULTS

Overall, 45 of 110 patients (41%) with erectile dysfunction after RRP had penile fibrotic changes, representing 11% of all patients undergoing RRP in the specified period. The primary clinical presentation included penile curvature in 42 men (93%) and 'waistband' deformity in 11 (24%; some had both); palpable plaques were present in 31 (69%). On assessing the outcome in 40 men, 16 (40%) felt that their condition had improved, half were unchanged and 10% progressed, within a mean follow-up of 24 months after diagnosis. Of the 16 improved, 14 were regularly using a vacuum constriction device or injection therapy. No significant factors predictive of the fibrotic changes could be identified, including the use of intracavernosal injection therapy before onset, neurovascular bundle resection, operative duration, estimated blood loss and pathological tumour grade or stage.

CONCLUSIONS

Penile fibrotic changes are a significant but previously undescribed problem in men after RRP. Although predisposing factors could not be identified, most men felt that their condition stabilized or improved during treatment. Corroborative confirmation of this association and its aetiology will require prospective studies.

What's new in Peyronie's disease

Within the past year further scientific studies have been performed to find the aetiology of Peyronie's disease. Advances in the conservative management of the disease by extracorporeal shockwave therapy have been reported in many centres. The operation of plaque excision and grafting, which has been performed for over 25 years, has now been replaced by the superior operation of plaque incision with venous patch.