Pathophysiology and Future Therapeutic Perspectives for Resolving Fibrosis in Peyronie’s Disease

Early-onset and uncontrolled diabetes mellitus factors correlate with complications of Peyronie's disease

BACKGROUND

Peyronie's disease (PD) is a connective tissue disorder that affects the penis and is characterized by abnormal collagen structure in the penile tunica albuginea, resulting in plaque formation and penile deformity. PD's overall prevalence is estimated at 3.2% to 8.9%, with rates as high as 20.3% among men with type 2 diabetes mellitus (DM). However, the characteristics of DM associated with PD complications remain unclear.

AIM

To explore clinical associations between DM characteristics and PD complications.

METHODS

We conducted a retrospective analysis of patients with DM and PD who presented at our institution between 2007 and 2022. We examined patients' clinical histories, DM- and PD-related clinical parameters, and complications. Penile deformities were assessed through physical examination, photographs, and penile Doppler ultrasound. Patients were categorized into subgroups based on age of DM onset: early (<45 years), average (45-65 years), and late (>65 years).

OUTCOMES

Outcomes included effects of DM characteristics on PD development, progression, and severity.

RESULTS

In total, 197 patients were included in the evaluation. Early-onset diabetes and elevated hemoglobin A1c (HbA1c) levels exhibited significant correlations with the early development of PD (ρ = 0.66, P < .001, and ρ = -0.24, P < .001, respectively). Furthermore, having DM at an early age was associated with the occurrence of penile plaque (ρ = -0.18, P = .03), and there were no significant differences in plaque dimensions (ρ = -0.29, P = .053). A rise in HbA1c levels after the initial PD diagnosis displayed positive correlations with the formation of penile plaque (ρ = 0.22, P < .006).

CLINICAL IMPLICATIONS

These findings emphasize the need for comprehensive assessments and personalized treatment strategies for individuals with DM and PD. Enhanced management approaches can improve outcomes for those facing both challenges.

STRENGTHS AND LIMITATIONS

Limitations include the single-site retrospective design with potential selection bias, inaccuracies in medical record data, and challenges in controlling confounding variables.

CONCLUSIONS

This study highlights that early-onset diabetes and poor diabetes control, as indicated by a subsequent rise in HbA1c levels following PD diagnosis, are significantly correlated with the onset and severity of PD. Revealing the mechanisms behind these findings will help us develop better management strategies for individuals with DM and PD.

Ameliorative effects of sildenafil against carbon tetrachloride induced hepatic fibrosis in rat model through downregulation of osteopontin gene expression

The liver carries out many essential tasks, such as synthesising cholesterol, controlling the body's storage of glycogen, and detoxifying metabolites, in addition to performing, and regulating homeostasis. Hepatic fibrosis is a pathological state characterized by over accumulation of extracellular matrix (ECM) including collagen fibers. Sildenafil (a selective inhibitor of type 5 phosphodiesterase) has anti-inflammatory, antioxidant and anti-apoptotic properties. It is commonly used to treat erectile dysfunction in male. The purpose of the current investigation was to evaluate sildenafil's hepatoprotective potential against liver fibrosis in rats that was caused by carbon tetrachloride (CCl4). Liver enzymes and oxidative markers as well as profibrotic genes were determined. The findings showed that sildenafil alleviates the hepatic dysfunctions caused by CCl4 by restoring normal levels of ALT, AST, and GGT as well as by restoring the antioxidant status demonstrated by increased glutathione (GSH), and catalase. In addition, a significantly down-regulated the mRNA expressions of profibrotic genes [collagen-1α, IL-1β, osteopontin (OPN), and transforming growth factor-β (TGF-β)]. Additionally, sildenafil lessens the periportal fibrosis between hepatic lobules, congestion and dilatation in the central vein, and the inflammatory cell infiltrations. As a result, it is hypothesized that sildenafil may be helpful in the management of hepatotoxicity brought on by CCl4 through suppressing OPN.

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.

A new alternative approach to management of acute phase Peyronie's disease: low intensity extracorporeal shockwave therapy and platelet-rich plasma

BACKGROUND

The aim of this study was to investigate the efficacy, safety, and outcomes of the combination of low ıntensity external shock wave therapy (Li-ESWT) and platelet-rich plasma (PRP) therapy in acute phase Peyronie's disease (PD).

METHODS

The datas of patients admitted with acute phase Peyronie's between January 2014 and January 2022 were reviewed retrospectively. In total, we included total 159 patients who used combination of vitamin E 600 mg/day plus colchicine 1.5 mg/day plus oral daily 5 mg tadalafil (N.=77) in group 1 and received Li-ESWT+PRP combination therapy plus oral daily 5 mg tadalafil (N.=82) in group 2. We noted characteristics of fibrous plaques, pain status, penile curvature degree, and erectile function parameters. All patients were visited at the 3rd and 12th months after the treatment.

RESULTS

Preoperative demographic characteristics were similar in the two groups. There was a statistically significant improvement in the mean plaque size, penile curvature degree, IIEF-5 and VAS scores in the intervention group after the treatment. Ecchymosis and hematoma were not observed at the injection site and Li-ESWT application areas in the intervention group. No local or systemic drug reactions were noted in either group.

CONCLUSIONS

Combination of Li-ESWT and PRP are highly effective and safety to early treatment in the acute phase PD.

TGF-β1 induces formation of TSG-6-enriched extracellular vesicles in fibroblasts which can prevent myofibroblast transformation by modulating Erk1/2 phosphorylation

Extracellular vesicles have emerged as important mediators of cell-to-cell communication in the pathophysiology of fibrotic diseases. One such disease is Peyronie's disease (PD), a fibrotic disorder of the penis caused by uncontrolled transformation of resident fibroblasts to alpha-smooth muscle actin positive myofibroblasts. These cells produce large amounts of extracellular matrix, leading to formation of a plaque in the penile tunica albuginea (TA), causing pain, penile curvature, and erectile dysfunction. We have used primary fibroblasts derived from the TA of PD patients to explore the role of transforming growth factor beta 1 (TGF-β1), a key signalling factor in this process. TGF-β1 treatment elicited a range of responses from the myofibroblasts: (i) they secreted extracellular vesicles (EVs) that were more numerous and differed in size and shape from those secreted by fibroblasts, (ii) these EVs prevented TGF-β1-induced transformation of fibroblasts in a manner that was dependent on vesicle uptake and (iii) they prevented phosphorylation of Erk1/2, a critical component in modulating fibrogenic phenotypic responses, but did not affect TGF-β1-induced Smad-signalling. We posit that this effect could be linked to enrichment of TSG-6 in myofibroblast-derived EVs. The ability of myofibroblast-derived vesicles to prevent further myofibroblast transformation may establish them as part of an anti-fibrotic negative feedback loop, with potential to be exploited for future therapeutic approaches.

The pathogenic role of the immune system in erectile dysfunction and Peyronie's disease: focusing on immunopathophysiology and potential therapeutic strategies

INTRODUCTION

Erectile dysfunction (ED) represents the major cause of male sexual dysfunction, which is often associated with obesity, diabetes mellitus, atherosclerotic cardiovascular disease, and cigarette smoking. Peyronie's disease is a chronic disorder associated with irreversible fibrotic damage of the tunica albuginea leading to ED, painful erection, coital disturbance, and physical and social complaints. Both conditions are characterized by chronic inflammation, oxidative stress, and significant changes in intracavernous hydrodynamics. In this scenario, oxidized lipoproteins, M1-polarized macrophages, proinflammatory cytokines (such as the tumor necrosis factor α), endothelial nitric oxide synthase, penile smooth muscle cells, and toll-like receptors represent the main triggers of the inflammatory process in ED. Phosphodiesterase-5 inhibitors are the most common treatment for ED. This treatment is used intermittently, as it is conceived as a symptomatic and not curative therapy. Moreover, not all patients respond to phosphodiesterase-5 inhibitors (35%-85%), particularly those with dysmetabolic phenotypes. Additional or alternative treatments are therefore desirable, mostly in refractory cases.

OBJECTIVES

In this review, we describe the immune-mediated pathogenesis of ED and Peyronie's disease (PD). In our literature search we placed particular emphasis on potentially practical therapeutic approaches, including natural products (such as polyphenols), due to their anti-inflammatory and antioxidant activities, stem cell therapy, and platelet-derived preparations.

METHODS

We searched PubMed/MEDLINE, Web of Science, Scopus, Cochrane Library, Google Scholar, and institutional websites. Original studies, narrative reviews, systematic reviews, and meta-analyses written in English were searched, screened, and selected.

RESULTS

In animal models of ED and PD, therapeutic approaches, including anti-inflammatory and antioxidant agents, stem cell therapy, and platelet-derived preparations, have provided positive results, including improved penile function, reduced inflammation and oxidative stress, and promotion of tissue repair. However, clinical evidence of improvement in human patients is still insufficient.

CONCLUSION

Promising results for treating ED and PD have been shown in preclinical and pilot clinical studies, but specific clinical trials are needed to validate the efficacy of these therapeutic approaches in men with ED.

Single-cell RNA sequencing reveals critical modulators of extracellular matrix of penile cavernous cells in erectile dysfunction

Erectile dysfunction (ED) is a common and difficult to treat disease, and has a high incidence rate worldwide. As a marker of vascular disease, ED usually occurs in cardiovascular disease, 2-5 years prior to cardiovascular disease events. The extracellular matrix (ECM) network plays a crucial role in maintaining cardiac homeostasis, not only by providing structural support, but also by promoting force transmission, and by transducing key signals to intracardiac cells. However, the relationship between ECM and ED remains unclear. To help fill this gap, we profiled single-cell RNA-seq (scRNA-seq) to obtain transcriptome maps of 82,554 cavernous single cells from ED and non-ED samples. Cellular composition of cavernous tissues was explored by uniform manifold approximation and projection. Pseudo-time cell trajectory combined with gene enrichment analysis were performed to unveil the molecular pathways of cell fate determination. The relationship between cavernous cells and the ECM, and the changes in related genes were elucidated. The CellChat identified ligand-receptor pairs (e.g., PTN-SDC2, PTN-NCL, and MDK-SDC2) among the major cell types in the cavernous tissue microenvironment. Differential analysis revealed that the cell type-specific transcriptomic changes in ED are related to ECM and extracellular structure organization, external encapsulating structure organization, and regulation of vasculature development. Trajectory analysis predicted the underlying target genes to modulate ECM (e.g., COL3A1, MDK, MMP2, and POSTN). Together, this study highlights potential cell-cell interactions and the main regulatory factors of ECM, and reveals that genes may represent potential marker features of ED progression.

[Current treatment concepts for Peyronie's disease]

Plastic induration of the penis (PIP, Peyronie's disease) is an acquired and chronic disease of the penis, which is characterized by penile pain, distortion and deformation of the penis as well as the resulting impairments in sexual activity of the patient. The most probable causes are microtrauma and macrotrauma within the tunica albuginea of the corpora cavernosa, which due to an abnormal wound healing subsequently leads to the formation of fibrosis in this region. Various predisposing factors and also a genetic predisposition are discussed. The PIP occurs most frequently in the fifth to sixth decades of life. The prevalence is 0.3-20% depending on the investigated collective and the risk factors present. The PIP is subdivided into an acute inflammatory phase and a chronic postinflammatory phase. Various conservative and surgical treatment options include oral medication, penile traction therapy, intralesional injections and surgical procedures.

The Use of Vacuum Devices as Adjuvant Therapy before and after Penile Curvature Surgery in Patients Affected by La Peyronie's Disease: Results from a Comparative Study

BACKGROUND

Peyronie's disease (PD) represents a challenging urological disease, due to not optimal post-operative surgical outcomes. We aim to retrospectively evaluate if vacuum erection device (VED) treatment before penile curvature surgery is able to improve post-operative surgical outcomes.

METHODS

All enrolled patients were assigned to the following groups: (a) the treatment group: VED treatment (three times per week) starting 3 months before surgery and (three times per week) one month after surgery; and (b) the control group: VED treatment (three times per week) one month after surgery. Follow-up urologic visits were scheduled for 3 and 6 months after surgery, and the two groups were compared.

RESULTS

A total of 38 patients were enrolled (median age 67 years, 57-74, IQR): 20 in the treatment group and 18 in the control group. At the follow-up visits, the two groups were different in terms of IIEF-5 (26 vs. 24; p = 0.02), "yes" to SEP2 and 3 (85% vs. 55%; p < 0.001, 85% vs. 50%; p < 0.001, respectively), and PDQ (-16 vs. -11; p = 0.03). Complete correction of penile curvature was achieved in 36 patients (94.7%). In the treatment group, no hourglass deformity was reported, whereas one patient reported a mild hourglass deformity in the control group. In the treatment group, we obtained a longer total penile length (median +1.5 cm). The overall satisfaction rate was 98% in the treatment group and 96% in the control group.

CONCLUSIONS

The VED treatment before penile curvature surgery in patients affected by PD was able to improve surgical outcomes.

Molecular Mechanisms and Risk Factors Related to the Pathogenesis of Peyronie's Disease

Peyronie's disease (PD) is a benign condition caused by plaque formation on the tunica albuginea of the penis. It is associated with penile pain, curvature, and shortening, and contributes to erectile dysfunction, which worsens patient quality of life. In recent years, research into understanding of the detailed mechanisms and risk factors involved in the development of PD has been increasing. In this review, the pathological mechanisms and several closely related signaling pathways, including TGF-β, WNT/β-catenin, Hedgehog, YAP/TAZ, MAPK, ROCK, and PI3K/AKT, are described. Findings regarding cross-talk among these pathways are then discussed to elucidate the complicated cascade behind tunica albuginea fibrosis. Finally, various risk factors including the genes involved in the development of PD are presented and their association with the disease summarized. The purpose of this review is to provide a better understanding regarding the involvement of risk factors in the molecular mechanisms associated with PD pathogenesis, as well as to provide insight into disease prevention and novel therapeutic interventions.

Incremental Treatment Response by Cycle With Collagenase Clostridium Histolyticum for Peyronie's Disease: A Pooled Analysis of Two Phase 3 Trials

OBJECTIVE

To evaluate cumulative and incremental changes in penile curvature after each treatment cycle of collagenase clostridium histolyticum (CCH) in men with Peyronie's disease (PD).

METHODS

Data from 2 phase 3, randomized, placebo-controlled trials were analyzed post hoc. Treatment was administered in up to 4 treatment cycles (per cycle: 2 injections, 1-3 days apart, of CCH 0.58 mg or placebo; subsequent penile modeling) at 6-week intervals. Penile curvature was measured at baseline and after each treatment cycle (weeks 6, 12, 18, and 24). Successful response was defined as ≥20% reduction from baseline penile curvature.

RESULTS

Overall, 832 men (CCH, n = 551; placebo, n = 281) were included in the analysis. After each cycle, mean cumulative percent reduction from baseline penile curvature was significantly greater with CCH vs placebo (P <.001). Following one cycle, 29.9% of CCH recipients exhibited a successful response. Among nonresponders, additional cycles of injections led to further successful responses: 60.8% of first cycle failures achieved response after fourth cycle (8 injections), 42.7% of cycle 1-2 failures achieved response after fourth cycle, and 23.5% of cycle 1-3 failures achieved response after fourth cycle.

CONCLUSION

Data showed incremental benefits from each of the 4 CCH treatment cycles. Completion of a full series of 4 CCH treatment cycles may optimize improvements in penile curvature in men with PD, including among those who did not clinically respond to previous treatment cycles.

Statins synergize with phosphodiesterase type 5 inhibitors but not with selective estrogen receptor modulators to prevent myofibroblast transformation in an in vitro model of Peyronie's disease

BACKGROUND

Peyronie's disease (PD) is a fibrotic disorder characterized by plaque formation in the tunica albuginea (TA) of the penis, and we have previously shown that inhibition of transformation of TA-derived fibroblasts to myofibroblasts using a combination phosphodiesterase type 5 (PDE5) inhibitors and selective estrogen receptor modulators (SERMs) is effective in slowing the progression of early PD.

AIM

The study sought to investigate whether combinations of statins with PDE5 inhibitors or SERMs would affect myofibroblast transformation in vitro.

METHODS

Primary fibroblasts were isolated from TA of patients with PD and stimulated with transforming growth factor β1 in the absence and presence of a range of concentrations of statins, PDE5 inhibitors, SERMs, and their combinations for 72 hours before quantifying α-smooth muscle actin using in-cell enzyme-linked immunosorbent assay.

OUTCOMES

The prevention of transforming growth factor β1-induced transformation of TA-derived fibroblasts to myofibroblasts was measured in vitro.

RESULTS

Statins (simvastatin, lovastatin) inhibited myofibroblast transformation in a concentration-dependent manner with half maximal inhibitory concentration values of 0.77 ± 0.07 μM and 0.8 ± 0.13 μM, respectively. Simvastatin inhibited myofibroblast transformation in a synergistic fashion when combined with vardenafil (a PDE5 inhibitor; log alpha >0). Combination of tamoxifen (a SERM) and simvastatin did not show synergy (log alpha <0). When 3 drugs (simvastatin, vardenafil, and tamoxifen) were combined, the effect was not synergistic, but rather was additive.

CLINICAL IMPLICATIONS

A combination of a statin with a PDE5 inhibitor might be useful in the clinic to slow the progression of the disease in patients with early PD; however, caution should be taken with such a combination because of the reported myopathy as a side effect.

STRENGTHS AND LIMITATIONS

The use of primary human cells from patients with PD is a strength of this study. The mechanisms by which these drug classes exert synergy when used in combination was not investigated.

CONCLUSION

This is the first demonstration of an antifibrotic synergy between statins and PDE5 inhibitors.

Significant inverse association of testosterone level with penile deformity severity in Japanese males with Peyronie's disease

OBJECTIVES

We evaluated the relationship between penile curvature and testosterone in Peyronie's disease patients treated in Japan.

METHODS

Data were obtained from 109 patients with Peyronie's disease treated with surgery at our hospital between April 2004 and December 2019. Penile deformity assessment was based on findings of a rigid erection induced by intracavernosal injection. Low total testosterone level was defined as <300 ng/dl. Patients were divided into two groups according to curvature severity (I, <60°; II ≥60°), then clinical factors including total testosterone were compared. Uni- and multivariate logistic regression analyses were performed to identify factors predicting severe penile deformity (≥60°).

RESULTS

For all patients, mean total testosterone was 469 ng/dl and median curvature was 50°, with a significant inverse correlation found between curvature and testosterone level (p < 0.0001). Group I and II patients numbered 55 and 54, respectively. Mean total testosterone for Group II was 397 ng/dl, significantly lower than Group I (539 ng/dl). Median curvature in 15 patients with a low testosterone level was 80°, significantly higher than those with a normal testosterone range (50°). Univariable and multivariable logistic regression analysis indicated total testosterone, follicle stimulating hormone, and C-reactive protein as significant factors correlated with severe penile deformity, among which total testosterone was most relevant.

CONCLUSION

The present findings confirmed that penile deformity severity is correlated with testosterone level in Japanese males with Peyronie's disease.

The Immunological Microenvironment and the Emerging Role of Stem Cells Therapy in Peyronie's Disease: A Systematic Narrative Review

Current literature has indicated that Peyronie's disease (PD) could be initiated by microtrauma and the subsequent inflammation episodes that follow. PD could be sorted into acute or chronic status, and it can differ when selecting the clinical therapeutics. PD would cause pain and penile deformity to diseased men and impair their erectile function. Occasionally, surgical revision of the penis might be needed to correct the penile curvature. We find that there are limited effective options of intra-lesion injections for the PD plaques. By searching the databases and screening the literature with the PRISMA 2020 guideline, we observed that several preclinical studies that applied stem cell therapy in treating PD were fruitful in the acute phase. Although in the chronic phase of PD, erectile parameters were not significantly improved, and therefore, future studies might be better elevated in certain aspects, such as the sites selected for harvesting stem cells or changing the centrifugation forces. In this review, we concluded the contemporary understanding of inflammatory microenvironments in PD, the stem cell therapy in PD, and our perspectives on future studies. We concluded that there may be great potential in stem cell therapy for treating both acute and chronic phases PD.

Phenotypic screening of 1,953 FDA-approved drugs reveals 26 hits with potential for repurposing for Peyronie's disease

Drug repurposing has been shown to bring safe medications to new patient populations, as recently evidenced by the COVID-19 pandemic. We investigated whether we could use phenotypic screening to repurpose drugs for the treatment of Peyronie's disease (PD). PD is a fibrotic disease characterised by continued myofibroblast presence and activity leading to formation of a plaque in the penile tunica albuginea (TA) that can cause pain during erection, erectile dysfunction, and penile deformity. PD affects 3-9% of men with treatment options limited to surgery or injection of collagenase which can only be utilised at late stages after the plaque is formed. Currently there are no approved medications that can be offered to patients presenting with early disease before the formation of the plaque. Drug repurposing may therefore be the ideal strategy to identify medical treatments to address this unmet medical need in early PD. We used primary human fibroblasts from PD patients in a phenotypic screening assay that measures TGF-β1-induced myofibroblast transformation which is the main cellular phenotype that drives the pathology in early PD. A library of FDA-approved 1,953 drugs was screened in duplicate wells at a single concentration (10 μM) in presence of TGF-β1. The myofibroblast marker α-SMA was quantified after 72h incubation. A positive control of SB-505124 (TGF-β1 receptor antagonist) was included on each plate. Hits were defined as showing >80% inhibition, whilst retaining >80% cell viability. 26 hits (1.3%) were identified which were divided into the following main groups: anti-cancer drugs, anti-inflammation, neurology, endocrinology, and imaging agents. Five of the top-ten drugs that increase myofibroblast-transformation appear to act on VEGFR. This is the first phenotypic screening of FDA-approved drugs for PD and our results suggest that it is a viable method to predict drugs with potential for repurposing to treat early PD.

Identifying hub genes, key pathways and key immune-related genes in Peyronie's disease by integrated bioinformatic analysis

Scarring diseases, such as Peyronie's disease (PD), usually lead to disorders in the immune system. Previous studies suggested that the PD process was regulated by immune signaling. However, the pathogenetic mechanism remains incompletely characterized. This article used bioinformatic approaches to identify hub genes, key pathways and key immune-related genes that play essential roles in PD pathogenesis. Two Gene Expression Omnibus (GEO) datasets, GSE126005 and GSE146500, were used to analyse the transcriptional profiling in both PD and normal samples. R software was applied to examine the difference in the expression of hub genes and key immune-related genes. The candidates for hub genes were further validated through protein-protein interactions (PPIs), gene correlation, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. In addition, candidate miRNA‒mRNA pairs were functionally assessed. A total of 39 candidate genes were identified, the expression levels of which in PD fibroblast cells were different from those in normal cells (16 showed reduced expression in PD and 21 candidates overexpressed in PD). We found that these genes could interact with each other through PPI analysis. According to the functional enrichment analysis, the candidates may regulate some major biological processes, including cytokine‒cytokine receptor interactions and the JAK-STAT signaling pathway. IL6, IL21R, IFNE, CXCL2, EGF, and ANGPTL5 were identified as key immune-related genes. The findings may help understand the role of immunologic contributors in PD, thus shedding light on the development of more effective strategies to prevent and treat this kind of disease.

A Consistent Lack of Consistency in Defining the Acute and Chronic Phases of Peyronie's Disease: A Review of the Contemporary Literature

INTRODUCTION

Treatment recommendations for Peyronie's Disease (PD) differ based on whether a patient is in the acute/active versus chronic/stable phase of the disease, yet there are no agreed upon criteria for defining these clinical entities.

OBJECTIVES

To review the criteria used to define acute and chronic phase PD in modern PD intervention studies.

METHODS

We performed a search engine review to identify indexed publications for PD intervention studies and review articles / meta-analyses from the year 2011-2020. Outcomes results were catalogued and summarized across articles. As a result of the substantial heterogeneity of outcome measures and follow-up intervals, meta-analytic techniques were not applied to the data analysis.

RESULTS

We identified a total of 104 studies that met inclusion criteria and had available information for review (n = 79 primary intervention studies; n = 25 review articles/meta-analyses/guidelines). Among the queried studies, we were unable to identify a consensus with respect to the criteria used to define acute and chronic phases of PD. 33% of primary intervention studies did not specifically define their criteria for acute and chronic phase PD, despite referencing these populations as part of the inclusion criteria in many instances. Studies used heterogenous criteria including total symptom duration, duration of "stable" symptoms, and presence/absence of pain.

CONCLUSION

Due to varying definitions across the literature, we were unable to create a standardized definition of acute and chronic phase Peyronie's in terms of time. Our findings emphasize the need for greater consensus in defining the treatment cohorts with future studies that assess treatment for men with PD.

Bioinformatics-Based Identification of Potential Hypoxia-Related Genes Associated With Peyronie's Disease

Hypoxia is one of the most important predisposing conditions for Peyronie’s disease (PD) and the pathogenetic mechanism is yet to be completely elucidated. This study applied bioinformatic approaches to select candidate hypoxia-related genes involved in the pathogenesis of PD. The Gene Expression Omnibus (GEO) data set GSE146500 was introduced to compare the transcriptional profiling between normal and PD samples. The differential expression of hypoxia-related gene was determined with R software. On the selected candidate genes, further functional analyses were applied, including protein–protein interactions (PPIs), gene correlation, gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway. A total of 66 candidate genes (24 candidates overexpressed in PD and 42 showing reduced expression in PD) were distinguished according to the differential expression between human fibroblast cells from normal and PD patients. The interactions among these candidate genes were recognized according to PPI analysis. The functional enrichment analyses revealed the potential modulatory functions of the candidate genes in some major biological processes, especially in glycolysis/gluconeogenesis and carbon metabolism. The findings would facilitate further study on the pathogenesis of PD, which might consequently promote the improvement of clinical strategies against PD.

ABO Blood Type and Risk of Peyronie's Disease in Japanese Males

PURPOSE

Although multiple mechanisms associated with Peyronie's disease (PD) have been proposed, details regarding etiologic factors, especially genetic, remain unclear. We examined the relationship of the ABO blood type system, known as a genetic factor associated with susceptibility to a number of diseases, with PD in Japanese males.

MATERIALS AND METHODS

We compared 202 Japanese PD patients treated with surgery at our hospital between March 2004 and December 2019 with 846 randomly selected non-PD male patients who underwent urological surgery during the same period regarding distribution of ABO blood types. In addition, we assessed the risk of PD according to blood type group among all study participants using odds ratio (OR) and 95% confidence interval (CI) calculations.

RESULTS

The distribution of individual blood types in the control group was nearly the same as that in the general Japanese population. In contrast, O, A, B, and AB blood types were noted in 37.6%, 36.1%, 14.9% and 11.4%, respectively, of the PD patients, which was significantly different from the control group, where blood type O was found in 29.1% and B in 23.2% (p<0.05). Our results showed that as compared with patients with blood group B, those with another blood type were more likely to develop PD, among which type O had a significantly increased OR of 2.018 (CI, 1.271-3.205).

CONCLUSIONS

These are the first reported results showing that ABO blood type may be associated with risk of PD, though further investigations are needed.

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.

Downregulation of miR-29b is associated with Peyronie's disease

BACKGROUND

Peyronie's disease (PD) is characterized by the formation of fibrous plaque in tunica albuginea, causing several problems in patients. The etiology of this disease is not fully understood, and there are few effective treatments. To better understand the molecular pathways of PD, we studied miR-29b, a microRNA that could be involved with this illness. MicroRNAs are endogenous molecules that act by inhibiting messenger RNA. MiR-29b regulates 11 of 20 collagen genes and the TGF-β1 gene, which are related to PD progression.

METHODS

We compared miR-29b expression in 11 patients with PD and 14 patients without PD (control group). For the patients with PD, we utilized samples from the fibrous plaque (n = 9), from the tunica albuginea (n = 11), and from the corpus cavernosum (n = 8). For the control group, we utilized samples from the tunica albuginea (n = 14) and from the corpus cavernosum (n = 10). MiR-29b expression was determined by q-PCR.

RESULTS

We found a downregulation of miR-29b in the fibrous plaque, tunica albuginea and corpus cavernosum of patients with PD in comparison with the control group (p = 0.0484, p = 0.0025, and p = 0.0016, respectively).

CONCLUSION

Although our study has a small sample, we showed for the first time an evidence that the downregulation of miR-29b is associated with PD.

Surgical Reconstruction of Penile Curvature due to Peyronie's Disease by Plaque Incision and Buccal Mucosa Graft

BACKGROUND/AIM

We aimed to evaluate the effectiveness and safety of penile plaque incision and buccal mucosa grafting in patients with stable-phase Peyronie's disease (PD).

METHODS

This was a prospective evaluation of patients with stable-phase PD who were treated by plaque incision and buccal mucosa grafting. Preoperative evaluation included International Index of Erectile Function Questionnaire (IIEF-5), measurement of erect penile length, and penile Doppler ultrasound during prostaglandin-induced erection. At 3- and 24-month follow-up visits, penile length and residual curvature were measured along with penile Doppler ultrasound and IIEF5 questionnaires. Patient and sexual partner satisfaction were also assessed at 24-month-visit.

RESULTS

The study was completed with 20 patients (mean age 46.5 ± 9.9 years). Dorsal curvature was the most frequent site of curvature (45%). The median curvature at preoperative evaluation was 45°(range 40-90°). The postoperative median curvatures were 5°(5-10, IQR) and 7°(5-10, IQR) at 3- and 24-month postoperatively, respectively. Success rate was 95% at 3-month and 90% at 24-month. There was no significant penile shortening. The mean IIEF-5 score was 17.5 ± 2.2 at preoperative evaluation. The median IIEF-5 scores were calculated as 20.1 ± 2.2 and 21.3 ± 2.2 at 3-month and 24-month visits, respectively (p<0.0001). Compared with baseline IIEF-5 score, both postoperative IIEF-5 scores were significantly higher. There was no de novo erectile dysfunction. There were no serious complications during and after the surgery. Ten percent of patients were poorly satisfied with the results of the surgery.

CONCLUSION

Corporoplasty with buccal mucosa graft led to excellent structural and functional results and patient satisfaction. Ainayev Y, Zhanbyrbekuly U, Gaipov A, et al. Surgical Reconstruction of Penile Curvature due to Peyronie's Disease by Plaque Incision and Buccal Mucosa Graft. J Sex Med 2021;18:1308-1316.

[Efficacy and safety of local injections treatments for Peyronie's disease: Review of the literature]

AIM

To assess the efficacy and safety of local injection used to reduce penile curvature in Peyronie's disease.

METHODS

A review of the literature was carried out according to the PRISMA guidelines (Preferred Reporting Items for Systematic Reviews and Meta-Analyzes) on the Medline database in April 2020, with the research: "collagenase"[All Fields] OR "Interferon"[All Fields] OR "verapamil"[All Fields] OR "betamethasone"[All Fields] OR "hyaluronic acid"[All Fields] OR "Platelet-Rich Plasma"[All Fields] OR "Stem Cells"[All Fields] AND "peyronie's"[All Fields] AND Controlled Clinical Trial[ptyp]. Only controlled studies with placebo group were included in this review.

RESULTS

Of the 35 articles identified, 6 placebo-controlled studies were finally included. Intra-plaque injections of verapamil did not show improvement in penile curvature. Injections of interferon α 2b and clostridium histolyticum collagenase allowed a statistically significant improvement in terms of curvature reduction: 13.5 versus 4.5 degrees P<0.01) and 17 versus 9.3 degrees P<0.0001 respectively. However, interferon α 2b is not available in France for Peyronie's disease and clostridium histolyticum collagenase is no longer authorized since March 1, 2020. No controlled studies are available on corticosteroids, hyaluronic acid, platelet-rich plasma or stem cells injections.

CONCLUSION

To correct the deformity in Peyronie's disease in the chronic phase, there is no effective solution currently available in France based on controlled studies. Surgery retains its place for the correction of a curvature of at least 30° associated with a sexual handicap in the stable phase, however at the cost of potential adverse effects. Stem cell or Platelet-Rich Plasma injection might be an injectable therapeutic alternative but need controlled studies.

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.

Patients with Dupuytren's Contracture, Ledderhose Disease, and Peyronie's Disease are at higher risk of arthrofibrosis following total knee arthroplasty

BACKGROUND

Total knee arthroplasty (TKA) is a successful treatment for patients with late stage osteoarthritis, yet arthrofibrosis remains a consistent cause of TKA failure. Dupuytren's, Ledderhose and Peyronie's Diseases are related conditions of increased fibroblast proliferation. The aim of this study was to identify whether an association exists between these conditions and arthrofibrosis following TKA.

METHODS

Patient records were queried from 2010 to 2016 using an administrative claims database to compare the rates of arthrofibrosis, manipulation under anesthesia (MUA), lysis of adhesions (LOA), and revision TKA in patients with independent chart diagnoses of Dupuytren's Contracture, Ledderhose, or Peyronie's Diseases versus those without. Complications were queried and compared using multivariate logistic regression.

RESULTS

Patients with Dupuytren's (n = 5,232) and Ledderhose (n = 50,716) had a significantly higher rate of ankylosis following TKA: 30-days (OR, 1.54; OR, 1.23), 90-days (OR, 1.20; OR, 1.24), 6-months (OR, 1.23; OR, 1.23), and 1-year (OR, 1.28; OR, 1.23), while patients with Peyronie's (n = 1,186) had a higher rate of diagnosis at 6-months (OR, 1.37) and 1-year (OR, 1.35). Patients with diagnoses of any of the fibroproliferative diseases had a statistically higher risk of MUA at 90-days, 6-month, and 1-year following primary TKA. These cohorts did not have a significantly higher rate of revision TKA.

CONCLUSION

There is an increased odds risk of arthrofibrosis and MUA in patients who have undergone TKA and have a diagnosis of Dupuytren's Contracture, Ledderhose, or Peyronie's Diseases. Improvements to frequency and application of post-operative treatment should be considered in these cohorts to improve outcomes.

Comparing and Contrasting Peyronie's Disease Guidelines: Points of Consensus and Deviation

BACKGROUND

Peyronie's disease (PD) is a challenging clinical entity. To assist clinicians with diagnosis and management, four separate organizations have published PD guidelines over the past five years, but there remains a lack of consensus and data-driven recommendations for many aspects of diagnosis and treatment.

AIM

To compare and contrast PD guidelines, highlighting key similarities and differences among the guideline panel recommendations and identify areas for further research.

METHODS

We performed an extensive review to compare and contrast diagnosis and treatment recommendations from publically available published PD guidelines from four different organizations: American Urological Association, European Association of Urology, Canadian Urologic Association, and the International Society of Sexual Medicine.

OUTCOMES

Key similarities and differences with regards to definition, evaluation, nonsurgical and surgical treatments were compared.

RESULTS

Points of general consensus among the guideline panels included: History is adequate for diagnosis of PD, and intracavernosal injection is a gold standard to evaluate penile deformity prior to invasive intervention. Careful counseling with shared decision-making is required prior to treatment. In general, plication and incision and/or grafting surgery is reserved for patients with preserved erectile function whereas penile prosthesis implantation is the only surgical option for PD patients with erectile dysfunction. Overall, nonsurgical treatments have inferior evidence of efficacy with these being the main area of controversy; however, all societies recognize that intralesional injections may be used. 0Further research into the pathophysiology of PD may direct novel treatments targeted towards early intervention and rigorous outcomes research may direct best practices for the surgical treatment of PD in the future.

CLINICAL IMPLICATIONS

PD is a challenging clinical entity. Direct comparison of the published PD guidelines highlights clear standards of care as well as areas where more research is needed to promote higher levels of evidence-based practice.

STRENGTHS & LIMITATIONS

To our knowledge this is the first report to directly compare and contrast published guidelines pertaining to the diagnosis and management of PD. Limitations include the lack of evidence-quality review pertaining to individual guideline recommendations, although this was not the aim of this review.

CONCLUSION

We highlight consensus of major urologic societies on many aspects of work up and management of PD with notable exceptions which may guide further research. Manka MG, White LA, Yafi FA, et al. Comparing and Contrasting Peyronie's Disease Guidelines: Points of Consensus and Deviation. J Sex Med 2021;18:363-375.

Minimally invasive therapies for Peyronie's disease: the current state of the art

Peyronie's disease (PD) is a relatively common condition that can result in significant penile deformity, sexual dysfunction, and psychological bother. Surgical straightening offers the highest probability of success during the stable phase of the disease. However, for men in the acute phase of PD or for those with less severe deformity who elect to avoid surgery, a variety of non-surgical treatment options are available. Oral therapies, including L-citrulline and pentoxifylline, are most useful as part of a combination regimen rather than as monotherapy. Intralesional therapy with IFN-α2b, verapamil, and collagenase clostridium histolyticum (CCH) can cause significant reduction in penile curvature, yet these results may not be clinically significant for men with more severe curvature. Further investigation into the timing of administration and optimal patient characteristics is required. Penile traction therapy offers a clinically significant improvement in penile length and curvature. However, this has traditionally required hours of daily therapy. Overall, a combination of oral, topical, injection and traction therapies may provide the most significant benefit among the non-surgical modalities for PD.

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.