Ca2+ channel blockers modulate metabolism of collagens within the extracellular matrix

Recurrence rates in the treatment of keloids and hypertrophic scars with intralesional triamcinolone combined with other intralesional agents

Hypertrophic scars (HTS) and keloids are pathologic scars that are products of a wound healing pathway error attributed to genetic and inflammatory causes (Leventhal et al., Arch Facial Plast Surg 8(6):362-368. https://doi.org/10.1001/archfaci.8.6.362 , 2006). Methods of pathologic scar treatment include intralesional agents, cryotherapy, surgical excision, pressure dressings, topical agents, laser resurfacing, radiotherapy, and other investigational therapies (Leventhal et al. 2006). The recurrence of pathologic scar is high across all treatment modalities, including the use of intralesional agents (Trisliana Perdanasari et al., Arch Plast Surg 41(6):620-629. https://doi.org/10.5999/aps.2014.41.6.620 , 2014). In the treatment of pathologic scar, combination approaches using intralesional agents, such as triamcinolone (TAC), 5-fluorouracil (5FU), verapamil (VER), bleomycin (BLM), and botulinum toxin (BTX), are superior therapies when compared to monotherapy (Yosipovitch et al., J Dermatol Treat 12(2):87-90. https://doi.org/10.1080/095466301317085363 , 2001; Yang et al., Front Med 8:691628. https://doi.org/10.3389/fmed.2021.691628 , 2021; Sun et al., Aesthetic Plast Surg 45(2):791-805. https://doi.org/10.1007/s00266-019-01570-8 , 2021). This review assesses recurrence and the reporting of recurrence in pathologic scar after treatment with intralesional triamcinolone (TAC) in combination with another intralesional agent. A literature review was conducted using research journals from PubMed using the following search terms: [(keloid) AND (triamcinolone) AND (combination) AND (intralesional)], as well as [(keloid) AND (triamcinolone) AND (combination)]. Articles were reviewed and included if the article analyzed  or compared intralesional agents for pathologic scar treatment within the last 10 years. The average follow-up period of included articles (n = 14) that utilized combination intralesional therapy (TAC-X) was approximately 11 months (range 1-24 months). Consistent recurrence rate reporting across studies was lacking. The combination agent with the highest recurrence rate was TAC-5FU (23.3%). The range of reported recurrence rates was 7.5-23.3%. Six studies using various intralesional combination regimens reported 0% recurrence over the follow-up period (TAC-5FU, TAC-BTX, TAC-BLM, TAC-CRY). Three studies did not report recurrence rates. While the efficacy of combination therapy is typically assessed via scar scales, the assessment of recurrence across studies of combination therapy is inconsistent and inadequate, with truncated follow-up periods. While scar recurrence can take place during 1-year post-treatment, long-term follow-up (18-24 months) is needed to characterize recurrence in the treatment of pathologic scar using various intralesional agents. Long-term follow-up periods allow patients to receive accurate prognostic information regarding recurrence after combination intralesional therapy. There are limitations to this review in that comparisons were made across studies with varying outcome variables, including scar size, injection concentration and interval, and follow-up period. Standardized follow-up periods and recurrence rate reporting are integral to furthering the understanding of these therapies and enhancing patient care.

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

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

Expanded Utilization of Intralesional Therapies for Treatment of Peyronie's Disease

Purpose

In this narrative review we explore additional indications for which intralesional collagenase Clostridium histolyticum (CCH) injection therapy may be used, in addition to those utilized in the IMPRESS trials. The goal is to provide updated assessment of available intralesional therapies and justify whether to expand clinical indications based on advancements over the last decade.

Results

Patients receiving CCH in the acute phase of PD have shown significant improvement in penile curvature - which may be even more significant than reported due to progressive curvature over the longitudinal course of injection therapy. Across studies, patients with ventral plaques achieved the greatest curvature improvement (~30°) compared to PD patients with dorsal or lateral plaques. Patients with curvature > 90° have been minimally documented. However, the concept of patients with higher degree of curvature achieving more significant degrees of improvement prevails across studies. Studies including PD patients with volume loss deformities or indentation(s) focus on curvature improvement and do not gauge improvement in these girth loss or indentation features specifically. PD patients with calcification may benefit from CCH, however, critical analysis of included study designs and results compared to placebo do not lend for strong support of CCH in PD at this time.

Conclusion

Based on the most recent research, the use of CCH in the acute phase of PD and patients with ventral penile plaques may be effective and safe. The limited available research on the efficacy of CCH on calcified plaque(s) and curvature greater than 90° is promising, however, more research is needed to ensure safety and success in this patient cohort. Finally, the current literature continues to show the use of CCH is not effective in PD patients with volume loss, indentation, or hourglass deformity. When expanding the use of CCH to patients not originally included in the IMPRESS trials, providers must prioritize minimizing chances of potential injury to urethral tissue. Finally, further investigation is required to determine whether CCH has utility for curvature greater than 90° or calcified plaques, although the limited available literature is promising.

An Eco-Friendly and Hopeful Promise Platform for Delivering Hydrophilic Wound Healing Agents in Topical Administration for Wound Disorder: Diltiazem-Loaded Niosomes

Purposes

Calcium channel blockers, such as diltiazem (DLZ), are important drugs for wound repair treatment. This current study used an ultrasonic method to increase the cutaneous delivery of (DLZ) niosomes.

Methods

The impact of the cholesterol:surfactant ratio on the DLZ-loaded niosome formulations was investigated. Differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, drug release, skin sensitivity, animal wound repair model, and histopathological assessment were applied to investigate the characteristics, morphology, and therapeutic effectiveness of the DLZ noisome.

Results

The results showed that changes in the cholesterol:surfactant ratio can influence the zeta potential and the size of the niosome. The maximum entrapment efficiency was observed to be about 94% when the cholesterol content in the formulation was high. The DLZ release studies revealed that the niosomal formulation was released slowly over the course of 24 h. Macroscopic observations of the wound demonstrated that wound closure in the DLZ-niosome-treated group and the commercial brand was equal and higher than in the other groups (gel base, placebo gel, and negative control). Pathological studies described that the wound repair in the DLZ-niosomal gel group was greater than in the other treatment. All the preparations tested for cutaneous irritation on Wistar rats showed the DLZ niosomal gels to be non-irritating.

Conclusion

The findings of this study revealed that the prepared DLZ-niosome could be used as a possible nano-vesicle for DLZ cutaneous delivery thus potentially opening up new prospects for the treatment of wound disorders.

Combined Verapamil-Polydopamine Nanoformulation Inhibits Adhesion Formation in Achilles Tendon Injury Using Rat Model

Introduction

Topical verapamil has been demonstrated to reduce the fibroproliferative scar. Therefore, it was hypothesized that topical verapamil could reduce adhesion formation after tendon repair. The current study aimed to examine the effects of verapamil-loaded polydopamine nanoparticles (VP-PDA NPs) on the adhesion formation of Achilles tendon laceration and repair in a rat model.

Methods

We randomly assigned 72 male Sprague-Dawley rats to the control, the PDA NPs, and the VP-PDA NPs groups (n = 24 per group). The quality of tendon healing was evaluated by the maximal tensile strength four and six weeks after surgery. The degree of tendon adhesion was scored on days 4, 15, 29, and 43 after surgery. The expressions of transforming growth factor-beta 1 (TGF-β1), vimentin, α-smooth muscle actin (α-SMA), and collagens type I and III were detected through Western blotting or immunohistochemistry at four weeks after surgery.

Results

In vitro release tests revealed that 61.3% of verapamil was released from VP-PDA NPs in four weeks. There was a significant increase in average failure to load in the VP-PDA NPs group (89.27 ± 5.09 N) compared with the PDA NPs group (65.52 ± 2.04 N) (p = 0.003) and the control group (74.52 ± 4.24 N) (p = 0.029). Adhesion scores were significantly reduced in the VP-PDA NPs group at six weeks (3.175 ± 0.08) and four weeks (3.35 ± 0.25) compared with the other groups. Moreover, VP-PDA NPs significantly reduced the expression of vimentin, α-SMA, TGF-β1, and collagens type I and III.

Conclusion

These data suggest that VP-PDA NPs reduced adhesion formation and enhanced tendon healing during rat tendon injury. Since topical verapamil has been used in clinics without side effects, VP-PDA NPs would have direct translation implications. However, its anti-adhesive effects on intrasynovial tendon injury must be examined.

Calpastatin-Mediated Inhibition of Calpain Ameliorates Skin Scar Formation after Burn Injury

Hypertrophic scars, the most common complication of burn injuries, are characterized by excessive deposition of fibroblast-derived extracellular matrix proteins. Calpain, a calcium-dependent protease, is involved in the fibroblast proliferation and extracellular matrix production observed in certain fibrotic diseases. However, its role in the formation of post-burn hypertrophic skin scars remains largely unknown. Here, calpain expression and activity were assessed in skin fibroblasts obtained directly from patients with third-degree burns, who consequently developed post-burn hypertrophic scars. Furthermore, the antifibrotic effect of calpastatin, an endogenous calpain inhibitor, was evaluated in human fibroblasts and a murine burn model. The activity, mRNA levels, and protein levels of calpain were markedly higher in fibroblasts from the burn wounds of patients than in normal cells. Selective calpain inhibition by calpastatin markedly reduced not only the proliferation of burn-wound fibroblasts but also the mRNA and protein expression of calpain, transforming growth factor-beta 1, α-smooth muscle actin, type I and type III collagens, fibronectin, and vimentin in burn-wound fibroblasts. The anti-scarring effects of calpastatin were validated using a murine burn model by molecular, histological, and visual analyses. This study demonstrates the pathological role of calpain and the antifibrotic effect of calpastatin via calpain inhibition in post-burn hypertrophic scar formation.

Verapamil-containing silicone gel reduces scar hypertrophy

A hypertrophic scar is a common dermal fibroproliferative lesion usually treated with topical silicone. Verapamil, a type of calcium channel blocker, is considered a candidate drug for the treatment of hypertrophic scars. Here, we report that the addition of verapamil to topical silicone gel enhances treatment outcomes of hypertrophic scars. Upon creation of hypertrophic scars with the rabbit ear model, varying concentrations of verapamil‐added silicone gel (0.1, 1, and 10 mg/g) were applied daily for 28 days. After the animals were euthanised, microscopic measurement was performed for (a) scar elevation index (SEI), (b) fibroblast count, and (c) capillary count. On gross analysis, features of hypertrophic scars were significantly alleviated in the verapamil‐added groups. On histologic examination, verapamil‐added groups showed (a) reduced SEI (1.93 (1.79‐2.67) for control vs 1.34 (1.21‐1.51) for silicone only and 1.13 (1.01‐1.65) for verapamil‐added silicone), (b) fibroblast count 700.5 (599.5‐838.5) for control, 613.25 (461‐762.5) for silicone only, and 347.33 (182.5‐527) for verapamil‐added silicone), and (c) capillary formation (52 (35.5‐96.5) for control, 46 (28‐64.5) for silicone only, and 39.83(24‐70) for verapamil‐added silicone) (Kruskal‐Wallis test, P < .05). On western blot, expression levels of collagen I protein was lower in the 1 mg/g and 10 mg/g verapamil‐added silicone compared with control. Therefore, we suggest a therapeutic concentration of verapamil‐added silicone gel of at least over 1 mg/g. Further study regarding maximally effective concentration and deeper insight into the mechanism of action should follow.

Use of calcium channel blockers in dermatology: a narrative review

Introduction: Calcium channel blockers (CCB) are commonly used for cardiovascular diseases. The evidence supporting the use of CCB in dermatology is mostly anecdotal and limited to case reports or small case series.Areas covered: This review article is divided into two parts. The first part discusses the therapeutic use of CCB in dermatology. The second part focuses on mucocutaneous adverse reactions due to the administration of CCB.Expert opinion: The use of CCB in dermatology is mainly based on its properties as a vasodilator and the inhibition of muscle contractions, such as pernio, anal fissures, facial wrinkles, and painful leiomyoma. However, there remain other modes of action to explain its clinical use in calcinosis, keloid, pressure ulcer, and fibromatosis. Compared to oral CCB, the lack of systemic side effects would make topical use of CCB an attractive alternative in the treatment of skin diseases, but the evidence for topical CCB is still limited, and there is a lack of standardized topical formulation. The main mucocutaneous adverse effects of CCB include gingival hyperplasia, phototoxicity, eczema, psoriasis and risk of skin cancers. Plausible factors for these adverse events include CCB's photoinstability, aldosterone synthesis inhibition, disturbed calcium homeostasis and immunosuppressive properties.

Prospective of extracellular matrix and drug correlations in disease management

The extracellular matrix (ECM) comprises of many structural molecules that constitute the extracellular environment. ECM molecules are characterized by specific features like diversity, complexity and signaling, which are also results of improvement or development of disease mediated by some physiological changes. Several drugs have also been used to manage diseases and they have been reported to modulate ECM assembly, including physiological changes, beyond their primary targets and ECM metabolism. This review highlights the alteration of ECM environment for diseases and effect of different classes of drugs like nonsteroidal anti-inflammatory drugs, immune suppressant drug, steroids on ECM or its components. Thus, it is summarized from previously conducted researches that diseases can be managed by targeting specific components of ECM which are involved in the pathophysiology of diseases. Moreover, the drug delivery focused on targeting the ECM components also has the potential for the discovery of targeted and site specific release of drugs. Therefore, ECM or its components could be future targets for the development of new drugs for controlling various disease conditions including neurodegenerative diseases and cancers.

Intralesional Injection Therapy and Atypical Peyronie's Disease: A Systematic Review

INTRODUCTION

Peyronie's disease (PD) is an inflammatory disorder of the tunica albuginea causing fibrotic changes including abnormal penile curvature, pain, and erectile dysfunction. Approximately 10% of PD patients will have atypical features including ventral plaques, hourglass deformities, unilateral indentations, severely shortened penile length, and multiplanar curvatures. Currently, the only intralesional treatment approved by the United States Food and Drug Administration is considered off-label for atypical PD. Furthermore, treatment of atypical PD, especially ventral plaques, is met with hesitation, in part due to potential urethral injury.

OBJECTIVES

To systematically review the available literature for the safety and efficacy of intralesional injections for atypical PD.

METHODS

A thorough literature search of the PubMed database was performed on manuscripts published between 1982 and 2020. Keywords included atypical Peyronie's disease, ventral plaque, hourglass deformity, and injection.

RESULTS

15 articles met the criteria for evaluation. Overall, 1,357 patients with PD were treated with intralesional therapy, of which 250 patients were considered to have an atypical presentation. 162 (648%) of the patients were treated with intralesional collagenase Clostridium histolyticum, 49 (19.6%) with verapamil, 29 (11.6%) with interferon alfa-2b, 5 (2.0%) with hyaluronic acid, and another 5 (2.0%) with onabotulinumtoxinA. There was only 1 reported severe adverse event (penile fracture), which was surgically repaired. There were no reports of urethral injury.

CONCLUSION

Intralesional injection treatment may be a safe alternative option for atypical PD. There is a great need for future research to closely monitor the role of intralesional therapy in this cohort. Choi EJ, Xu P, El-Khatib FM, et al. Intralesional Injection Therapy and Atypical Peyronie's Disease: A Systematic Review. Sex Med Rev 2021;9:434-444.

Impact of topical nifedipine on wound healing in animal model (pig)

Background

The human skin is an extremely sophisticated and evolved organ that covers the whole body. External agents or the patient’s own diseases can cause skin injuries that can challenge healthcare professionals and impose high social, economic and emotional costs.

Objectives

To evaluate the impact of topical nifedipine on skin wound healing, specifically on polymorphonuclear cells, vascular proliferation, and collagen.

Methods

We used three pigs, and created eight injuries in the dorsal region of each animal. We applied 1%, 10%, and 20% concentration nifedipine creams to four of the wounds in animals 1, 2, and 3 respectively and treated the other twelve wounds with saline solution 0.9% only. We analyzed the presence of polymorphonuclear cells, vascular proliferation, and collagen at six different times (days 1, 3, 7, 14, 21, and 28).

Results

The evaluation of polymorphonuclear levels showed mild cell activity at all times in the control group, while in the nifedipine groups, marked levels were more frequent at all times during the experiment. There was a 4.84-fold increase in the chance of marked vascular proliferation (p = 0.019) and, at the same time, a decrease in collagen formation (OR 0.02 / p = 0.005) in animal 3.

Conclusions

Topical NFD may have an impact on skin wound healing mechanisms. Our study showed that polymorphonuclear cells and vascular proliferation increased. We also demonstrated that collagen formation decreased. Therefore, topical NFD may have a positive impact on skin wound healing. Additional studies are needed to confirm our results.

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

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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

Ten-year experience with multimodal treatment for acute phase Peyronie's disease: A real life clinical report

OBJECTIVES

To present our experience with multimodal therapy for Peyronie's disease.

METHODS

Retrospective data were collected since 2008 to 2017. The following features were evaluated at baseline and after treatment: age, duration of disease, erectile function, erected penile curvature, and stretched penile length. All patients were offered the same protocol including: 12 intralesional verapamil injections, oral therapy (OT) ?L-arginine 2g once and pentoxifylline 400mg 3 times a day for 6 months?, and penile traction therapy. The adherence to each of the 3 components of multimodal treatment was evaluated.

RESULTS

One hundred and seventy-seven individuals were considered. Depending on the grade of adherence our survey was divided into 3 groups. Group 1: patients who only completed OT; group 2: men who accomplished OT and intralesional verapamil injections; group 3: patients who completed the entire protocol. Seventy-six, 45 and 56 men were assigned to group 1, 2 and 3 respectively. The mean age at the diagnosis was 59±8.4, 59.1±5.9 and 54.2±4.8 years, while the mean duration of the disease was 6.3±3.4, 4.8±2.9 and 3.9±3.1 months in group 1, 2 and 3. The erected penile curvature before and after treatment was 24.2±9 and 23.7±8.9° in group 1 (P<.36); 25.4±16.8 and 24.1±13.6° in group 2 (P<.34), and 34.3±17.9 and 26.1±17.2° in group 3 (P<.001).

CONCLUSIONS

OT alone was successful to block the progression of the disease. The add of intralesional verapamil injections to OT brought only mild improvements. The complete protocol significantly reduced erected penile curvature and improved erectile function.

Non-invasive treatment in the management of Peyronie's disease

Peyronies disease (PD) is estimated to affect approximately 3-9% of men worldwide and maybe associated with pain, erectile dysfunction and penile deformity including shortening. The condition has significant debilitating effects on quality of life, self-esteem and psychological wellbeing in addition to sexual function. Surgical results add further to this by patients having dissatisfaction with various aspects of outcomes. Non-surgical management may allow patients to avoid the morbidities associated with surgery and still achieve improved functional and aesthetic outcomes. Several non-surgical options are currently being employed in the treatment of PD that may reduce or stabilize both objective measures (e.g. penile length and deformity) and subjective measures (including sexual function, pain and partner satisfaction). Nonsurgical management can allow patients to avoid the morbidities associated with surgery and still achieve improved functional and aesthetic outcomes. In this article we explore the current non-surgical management options for PD including oral, mechanical therapies, intralesional and topical treatments. We also briefly discuss future treatment options in the form of stem cell therapy.

Devices for penile traction: the long and winding road to treating Peyronie's disease

INTRODUCTION

Penile traction therapy (PTT) is increasingly being recognized as a viable nonsurgical approach to Peyronie's disease (PD). The goal of this article is to review the current literature on PTT with attention to traction protocols, devices, and outcomes.

AREAS COVERED

Literature on the pathophysiology of PD, PTT as primary and adjunctive treatment for PD, perioperative use of PTT, and vacuum erection devices are all reviewed. Pertinent literature was obtained from the PubMed database. The key words 'penile traction,' 'mechanotransduction,' and 'Peyronie's disease' were searched and results were narrowed down based on relevance to the review.

EXPERT COMMENTARY

PTT appears beneficial but the true magnitude of effect is difficult to discern. Most studies are not randomized, have small sample sizes, lack control arms, or have varying traction protocols. Patient compliance is critical and new devices and traction protocols are needed to maximize the benefit of PTT.

Verapamil, a Calcium-Channel Blocker, Improves the Wound Healing Process in Rats with Excisional Full-Thickness Skin Wounds Based on Stereological Parameters

OBJECTIVE

Calcium can play noticeable roles in the wound-healing process, such as its effects on organization of F-actinin collagen bundles by fibroblasts at the injury site. In addition, calcium-channel blockers such as verapamil have antioxidant activity by increasing nitric oxide production that promotes angiogenesis, proliferation of fibroblasts, and endothelial cells in the skin-regeneration process. Therefore, in this study, the authors' objective was to investigate the effects of verapamil on the process of wound healing in rat models according to stereological parameters.

MATERIALS AND METHODS

In this experimental study, 36 male Wistar rats were randomly divided into 3 groups (n = 12): the control group that received no treatment, gel-base-treated group, and the 5% verapamil gel-treated group. Treatments were done every 24 hours for 15 days. Wound closure rate, volume densities of the collagen bundles and the vessels, vessel's length density and mean diameter, and fibroblast populations were estimated using stereological methods and were analyzed by the Kruskal-Wallis and Mann-Whitney U tests; P < .05 was considered statistically significant.

RESULTS

The verapamil-treated group showed a faster wound closure rate in comparison with control and gel-base groups (P = .007 and P = .011). The numerical density of fibroblasts, volume density of collagen bundles, mean diameter, and volume densities of the vessels in the verapamil group were significantly higher than those in the control and the base groups (P < .005).

CONCLUSIONS

The authors showed that verapamil has the ability to improve wound healing by enhancing fibroblast proliferation, collagen bundle synthesis, and revascularization in skin injuries.

A new treatment of hypertrophic and keloid scars with combined triamcinolone and verapamil: a retrospective study

Background

Since the management of keloid and hypertrophic scars still remains a difficult clinical problem, there is need for adequate, effective therapy. In this study, we explored for the first time the efficacy and the potential synergetic effect of combined triamcinolone and verapamil for the treatment of hypertrophic and keloid scars. The objective was to assess the efficacy of combined intralesional triamcinolone and verapamil therapy for hypertrophic and keloid scars.

Methods

Fifty-eight patients with hypertrophic scars (n = 31) and keloid scars (n = 27) were included. A specific injection therapy scheme was applied. Five follow-up moments were chosen, with a maximum follow-up of nearly 2 years. The effects of combination therapy on scar pliability, thickness, relief, vascularization, surface area, pain, and pruritus were examined by means of the Patient and Observer Scar Assessment Scale (POSAS).

Results

Our results reveal a fast and abiding improvement of both keloid and hypertrophic scars after treatment with the combination therapy. All POSAS components showed a reduction in scar score, while scar relief, pain, itchiness, and surface area improved significantly (P < 0.05) in keloids. Significant improvement in hypertrophic scars was found in scar pigmentation, vascularization, pliability, thickness, pain, and surface area. Overall POSAS scores revealed statistically significant decreases between baseline and 3–4 months, 4–6 months, and >12 months after start of therapy in both keloids and hypertrophic scars.

Conclusions

This study reveals that combined therapy of triamcinolone and verapamil results in overall significant scar improvement with a long-term stable result.

Level of evidence: Level IV, therapeutic study.

Understanding the cellular basis and pathophysiology of Peyronie's disease to optimize treatment for erectile dysfunction

Erectile dysfunction (ED) is a common condition that significantly impacts a man’s physical and psychological well-being. ED is often associated with Peyronie’s disease (PD), which is an abnormal curvature of the penis. Delayed treatment of or surgical invention for PD often results in ED and therefore unsatisfied patients. The pathophysiology of PD is incompletely understood, but has been studied extensively and based on our current understanding of PD physiology, many medical treatment options have been proposed. In this paper, we will review what is known about the pathophysiology of PD and the medical treatment options that have been trialed as a result. More investigations in regards to the basic science of PD need to be carried out in order to elucidate the exact mechanisms of the fibrosis, and propose new, more successful treatment options which should be implemented prior to the onset of ED.

Nonsurgical treatment options in Peyronie's Disease: 2016 update

Peyronie's disease (PD) is an inflammatory condition of penile tunica albuginea which commonly ends with penile curvature and difficulty in vaginal penetration. Unfortunately, the pathophysiology of PD has not been completely understood. In this paper, we will review what is known about the pathophysiology of PD and the nonsurgical medical treatment options that have been trialed as a result. In the last 5 years, commonly used oral medications left their places to intralesional therapies. Clostridium collagenase, which is the only Food and Drug Administration (FDA) approved treatment for PD, is now the most prescribed intralesional therapy in the last years. Clostridium collagenase is advised for patients whose penile curvature is > 30° and < 90°. Because of its side effects, patients should be counseled before intralesional Clostridium collagenase treatment. Until finding best treatment solution for PD, more investigations in regards to the basic science of PD need to be carried out in order to elucidate the exact mechanisms of the fibrosis.

Amlodipine in hypertension: a first-line agent with efficacy for improving blood pressure and patient outcomes

OBJECTIVES

Hypertension is well established as a major risk factor for cardiovascular disease. Although there is undeniable evidence to support the beneficial effects of antihypertensive therapy on morbidity and mortality, adequate blood pressure management still remains suboptimal. Research into the treatment of hypertension has produced a multitude of drug classes with different efficacy profiles. These agents include β-blockers, diuretics, ACE inhibitors, angiotensin receptor blockers and calcium channel blockers. One of the oldest groups of antihypertensives, the calcium channel blockers are a heterogeneous group of medications.

METHODS

This review paper will focus on amlodipine, a dihydropyridine calcium channel blockers, which has been widely used for 2 decades.

RESULTS

Amlodipine has good efficacy and safety, in addition to strong evidence from large randomised controlled trials for cardiovascular event reduction.

CONCLUSIONS

Amlodipine should be considered a first-line antihypertensive agent.

Effect of potassium channel openers in acute and chronic models of glaucoma

PURPOSE

Glaucoma is characterized by increased intraocular pressure (IOP). The effect of nicorandil and pinacidil on IOP in experimentally induced acute and chronic models of glaucoma and the mechanism of action involved were studied.

METHODS

New Zealand white rabbits were used for the study. After the measurement of IOP, nicorandil (1%), pinacidil (1%), and pilocarpine as standard (1%) were instilled topically into the left eye. The other eye served as control. Dextrose (5%) was used to induce acute glaucoma. IOP changes were recorded every 15 minutes until the pressure became normal. Freshly prepared α-chymotrypsin solution was introduced in the posterior chamber to induce chronic glaucoma. Rabbits with ocular hypertension were selected for the study. Similar drug solutions were used to study the effect on IOP. Glibenclamide, pilocarpine, and indomethacin (1%) were used to study the mechanism of action of both drugs. The IOPs were measured just prior to drug instillation and at suitable time intervals using a tonometer.

RESULTS

Pretreatment with topical nicorandil and pinacidil significantly lowered the rise in IOP in the acute model. Nicorandil and pinacidil initially caused rise in IOP for 15-30 minutes in chronic glaucoma. This was followed by reduction in IOP. Pretreatment with indomethacin and pilocarpine did not modify the effect of nicorandil and pinacidil on IOP. Pretreatment with glibenclamide blocked IOP from the lowering effect of nicorandil and pinacidil.

CONCLUSION

The oculohypotensive effect shown by these drugs appears to be attributable to enhancement of the aqueous humor outflow. This effect is perhaps mediated through potassium channels.

Inhibition of collagen synthesis by select calcium and sodium channel blockers can be mitigated by ascorbic acid and ascorbyl palmitate

Calcium, sodium and potassium channel blockers are widely prescribed medications for a variety of health problems, most frequently for cardiac arrhythmias, hypertension, angina pectoris and other disorders. However, chronic application of channel blockers is associated with numerous side effects, including worsening cardiac pathology. For example, nifedipine, a calcium-channel blocker was found to be associated with increased mortality and increased risk for myocardial infarction. In addition to the side effects mentioned above by different channel blockers, these drugs can cause arterial wall damage, thereby contributing to vascular wall structure destabilization and promoting events facilitating rupture of plaques. Collagen synthesis is regulated by ascorbic acid, which is also essential for its optimum structure as a cofactor in lysine and proline hydroxylation, a precondition for optimum crosslinking of collagen and elastin. Therefore, the main objective in this study was to evaluate effects of various types of channel blockers on intracellular accumulation and cellular functions of ascorbate, specifically in relation to formation and extracellular deposition of major collagen types relevant for vascular function. Effects of select Na- and Ca- channel blockers on collagen synthesis and deposition were evaluated in cultured human dermal fibroblasts and aortic smooth muscle cells by immunoassay. All channel blockers tested demonstrated inhibitory effects on collagen type I deposition to the ECM by fibroblasts, each to a different degree. Ascorbic acid significantly increased collagen I ECM deposition. Nifedipine (50 µM), a representative of channel blockers tested, significantly reduced ascorbic acid and ascorbyl palmitate-dependent ECM deposition of collagen type l and collagen type lV by cultured aortic smooth muscle cells. In addition, nifedipine (50 µM) significantly reduced ascorbate-dependent collagen type l and type lV synthesis by cultured aortic smooth muscle cells, assayed by measuring intracellular collagen content. We observed increased intracellular levels of ascorbate under supplementation with elevated doses of ascorbic acid, as well as its lipid soluble derivative ascorbyl palmitate. Nifedipine reduced ascorbic acid intracellular influx in cultured aortic smooth muscle cells with nifedipine (50 µM) compared to control. Adverse effects of nifedipine were neutralized either by an increased level of cell supplementation with ascorbic acid or by substituting it with ascorbyl palmitate. These studies suggest that adverse effects of channel blockers could be caused by their weakening the arterial wall integrity by interfering with proper extracellular matrix formation. In conclusion, these studies confirm the adverse effects of channel blockers on collagen type l and lV deposition, the key ECM components essential for maintaining optimal structural integrity of the arterial walls. Ascorbate supplementation reversed channel blocker inhibition of these collagen types synthesis and deposition. The results of this study imply the benefits of ascorbate and ascorbate palmitate supplementation in medical management of cardiovascular disease in order to compensate for adverse effects of channel blockers.

A review of the epidemiology and treatment of Peyronie's disease

Introduction

Peyronie’s disease (PD) has significant effect on patients and their partners. We provide a current review of the epidemiology as well as the nonsurgical and surgical treatment of PD.

Materials and methods

Review of literature pertaining to PD with focus on epidemiology and treatment options.

Conclusion

PD is common and likely underreported. The availability of new and highly effective treatment options will catalyze patient awareness and subsequently the prevalence of disease.

Verapamil inhibits scar formation after peripheral nerve repair in vivo

The calcium channel blocker, verapamil, has been shown to reduce scar formation by inhibiting fibroblast adhesion and proliferation in vitro. It was not clear whether topical application of verapamil after surgical repair of the nerve in vivo could inhibit the formation of excessive scar tissue. In this study, the right sciatic nerve of adult Sprague-Dawley rats was transected and sutured with No. 10-0 suture. The stoma was wrapped with gelfoam soaked with verapamil solution for 4 weeks. Compared with the control group (stoma wrapped with gelfoam soaked with physiological saline), the verapamil application inhibited the secretion of extracellular matrix from fibroblasts in vivo, suppressed type I and III collagen secretion and increased the total number of axons and the number of myelinated axons. These findings suggest that verapamil could reduce the formation of scar tissue and promote axon growth after peripheral nerve repair.

The History of Collagenase Clostridium Histolyticum

INTRODUCTION

After its U.S. FDA approval in 2013, Collagenase Clostridium histolyticum (CCh) has seen increasing use as a nonoperative treatment for Peyronie's disease (PD). We review the history of CCh and trials that led to its adoption.

AIM

To provide a historical and contemporary context for the evolution of Collagenase Clostridium histolyticum as a treatment modality for Peyronie's disease.

METHODS

A comprehensive search of peer-reviewed literature was performed pertaining to CCh and its biochemical and clinical significance.

MAIN OUTCOME MEASURE

The main outcome studied was the efficacy and safety profile of CCh in PD. CCh use in other diseases processes and its associated outcomes are also described.

RESULTS

CCh injection yields objective improvement in penile curvature across multiple trials in PD patients. Recently, level 1 strength of evidence has emerged supporting its widespread use. As such, CCh stands as the only FDA-approved injectable therapy for PD. Adverse events were namely limited to local reactions. Serious systemic complications and need for intervention were rare.

CONCLUSIONS

CCh is a safe and effective treatment for PD patients with deformities and plaque configuration amenable to injectable therapy. Multiple trials have demonstrated improvements in objective and subjective metrics such as penile curvature and bother scores. However, multiyear follow-up is needed to assess durability and its sustained clinical significance. Currently, refinement in dosing and technique has established a niche for CCh in PD patients who are affected by their symptoms but are not yet committed to surgical intervention. Yang KK and Bennett N. The history of collagenase clostridium histolyticum.

Effect of Topical Calcium Channel Blockers on Intraocular Pressure in Steroid-induced Glaucoma

Purpose: To evaluate the effect of 0.125% verapamil and 0.5% diltiazem eye drops on intraocular pressure (IOP) in steroid-induced glaucoma in rabbit eyes.

Methods: A total of 18 rabbits with steroid-induced glaucoma were divided into three groups (A, B and C; n = 6 each). Right eyes in groups A, B and C received 0.5% diltiazem, 0.125% verapamil and 0.5% timolol eye drops twice daily for 12 days, respectively; whereas, left eyes received distilled water. IOP was measured with Tono-pen XL at baseline, day 4, day 8, and day 12 of treatment.

Results: Both 0.5% diltiazem and 0.125% verapamil eye drops significantly reduced IOP compared to control eyes (p < 0.05). Reduction of IOP by 0.5% diltiazem, 0.125% verapamil eye drops were comparable to 0.5% timolol. No surface toxicity or systemic side effects were noted during the study period.

Conclusion: Calcium channel blockers, verapamil, and diltia-zem significantly reduced IOP in rabbiteyes. This group of drugs may have a potential role in treatment of glaucoma

How to cite this article: Ganekal S, Dorairaj S, Jhanji V, Kudlu K. Effect of Topical Calcium Channel Blockers on Intraocular Pressure in Steroid-induced Glaucoma. J Current Glau Prac 2014;8(1):15-19.

Suppression of gelatinase activity in human peripheral blood mononuclear cells by verapamil

OBJECTIVE

Gelatinases are a large group of proteolytic enzymes that belong to the matrix metalloproteinases (MMPs). MMPs are a broad family of peptidases, which proteolyse the extracellular matrix and have an important role in inflammation. Verapamil is a calcium channel blocker extensively used in the treatment of numerous cardiovascular diseases such as arrhythmia and hypertension. The anti-tumor and anti-inflammatory effects of verapamil have also been shown. In this study, the effect of verapamil on gelatinase activity in human peripheral blood mononuclear cells (PBMCs) has been assessed in vitro.

MATERIALS AND METHODS

In this experimental study, PBMCs from healthy adult volunteers were isolated by ficoll-hypaque-gradient centrifugation. The cells were then cultured in complete RPMI-1640 medium and after that incubated with different concentrations of verapamil (0-200 μM) in the presence or absence of phytoheamagglutinin (PHA) (10 μg/ml) for 48 hours. The gelatinase A (MMP-2)/gelatinase B (MMP-9) activity in cell-conditioned media was then evaluated by gelatin zymography. Statistical comparisons between groups were made by analysis of variance (ANOVA).

RESULTS

Verapamil significantly decreased the MMP-2/MMP-9 activity in human PBMCs after 48 hours incubation time compared with untreated control cells. The association was dose-dependent.

CONCLUSION

In this study verapamil exhibited a dose-dependent inhibitory effect on gelatinase A and gelatinase B activity in human PBMCs. It seems that the anti-inflammatory properties of verapamil may be in part due to its inhibitory effects on gelatinase activity. Regarding the beneficial effects of MMPs- inhibitors in the treatment of some cardiovascular diseases, the positive effect of verapamil on such diseases may be in part due to its anti-MMP activity. Verapamil with its inhibitory effects on gelatinases activity may be a useful MMP-inhibitor. Given the beneficial effect of MMP-inhibitors in some cancerous, inflammatory and autoimmune disorders, it seems likely that verapamil could also be used to treat these diseases.

Peyronie's disease: A contemporary review of non-surgical treatment

In this review I discuss the current non-surgical treatment options for Peyronie’s disease (PD), which remains a therapeutic dilemma for the treating physician. This is despite a large array of treatments that have been used since the time of de la Peyronie in the mid-18th century. Part of the problem with finding an effective treatment is the incomplete understanding of the aetiopathophysiology of this scarring disorder. Published articles in peer-reviewed journals were assessed, recognising that most of the reported trials are compromised by being single-centre studies with no placebo control. Various treatment options have emerged, most with limited and unreliable benefit, but a few treatments have shown a consistent, albeit incomplete, response rate. Currently the only scientifically sensible oral agents appear to be pentoxifylline, l-arginine, and possibly the phosphodiesterase type-5 inhibitors. The current intralesional injection treatment options include verapamil and interferon, with a reported benefit in reducing deformity and improving sexual function. Intralesional clostridial collagenase is in the midst of phase-3 trial analysis by the USA Food and Drug Administration. External mechanical traction therapy has recently emerged as a technique to reduce the curvature, recover lost length, and possibly obviate surgery. Currently there is no clear, reliable and effective non-surgical treatment for PD, but it appears that several of the available treatments can reduce the deformity and improve sexual function, and might at least stabilise the disease process.

Peyronie's disease: contemporary review of non-surgical treatment

BACKGROUND

Peyronie's disease (PD) remains a therapeutic dilemma for the treating physician. This is in spite of a large array of treatments which have been used since the time of de la Peyronie in the mid 18(th) century. Part of this problem is due to an incomplete understanding of the etiopathophysiology of this scarring disorder. Having a better understanding of the how and why the scarring occurs may help prevent progression, but ultimately reversing the existing scar remains the real challenge.

METHODS

This review discusses the current non-surgical treatment options for Peyronie's disease. Published articles in peer-reviewed journals are used, recognizing that the majority of the published trials are compromised by being single-center studies without a placebo control.

RESULTS

A variety of treatments options have emerged, most with limited and unreliable benefit, but a few treatments have shown a consistent albeit incomplete response rate. Could this suggest that all PD is not the same and that the heterogeneous nature of this scarring disorder may account for why some patients respond and others do not? Further investigation of this diverse response rate may yield insights into the pathophysiology of PD. In the meantime, there have been many oral treatments offered for PD. Currently the only scientifically sensible treatments appear to be pentoxifylline, L-arginine, and possibly the phosphodiesterase type-5 inhibitors. Intralesional injection has been used for many years. The current treatment options include verapamil and interferon, with reported benefit with respect to reduced deformity and improved sexual function. Intralesional clostridial collagenase is in the midst of phase 3 trial analysis by the FDA in the USA and may become the newest and only FDA approved treatment for Peyronie's disease. External mechanical traction therapy has also recently emerged as a technique to reduce curvature, recover lost length, enhance girth, and possibly obviate surgery.

CONCLUSIONS

It appears at this time that there is no clear, reliable and effective non-surgical treatment for Peyronie's disease, but it does appear from the published literature that several of the available treatments can result in reduction of deformity, improved sexual function, and may at a minimum stabilize the disease process so that deformity does not get worse particularly during the acute phase of this scarring disorder. Combination therapy in an effort to create a synergy between the chemical effects of oral and injectable drugs with the mechanical effects of external traction therapy may provide the best opportunity today for reduction of deformity in the man with Peyronie's disease.

Current and emerging treatment options for Peyronie's disease

Peyronie’s disease (PD) is a condition of the penis, characterized by the presence of localized fibrotic plaque in the tunica albuginea. PD is not an uncommon disorder, with recent epidemiologic studies documenting a prevalence of 3–9% of adult men affected. The actual prevalence of PD may be even higher. It is often associated with penile pain, anatomical deformities in the erect penis, and difficulty with intromission. As the definitive pathophysiology of PD has not been completely elucidated, further basic research is required to make progress in the understanding of this enigmatic condition. Similarly, research on effective therapies is limited. Currently, nonsurgical treatments are used for those men who are in the acute stage of PD, whereas surgical options are reserved for men with established PD who cannot successfully penetrate. Intralesional treatments are growing in clinical popularity as a minimally invasive approach in the initial treatment of PD. A surgical approach should be considered when men with PD do not respond to conservative, medical, or minimally invasive therapies for approximately 1 year and cannot have satisfactory sexual intercourse. As scientific breakthroughs in the understanding of the mechanisms of this disease process evolve, novel treatments for the many men suffering with PD are anticipated.

Pharmacological therapy in patients diagnosed with Peyronie's disease

Peyronie's disease is still a therapeutic dilemma for the urologist. Although medical treatment includes multiple versions, few therapeutic agents had significant effects. The combination between oral therapy and intralesional agents can improve the quality of life of the patients with Peyronie's disease.

Treatment of Peyronie's disease: 2012 update

Peyronie's disease (PD) is the occurrence of a fibrous inelastic scar of the tunica albuginea of the penis. It is a relatively common disorder among men, with a reported prevalence of 3% to 8%. It is often associated with penile pain, anatomical deformities in the erect state, and difficulty with intromission. Because the exact pathophysiology of PD remains unknown and standards for evaluating or reporting treatment outcomes are unclear, research on effective therapies has been limited. The benefits of nonsurgical treatment options are conflicting and further controlled studies are required before any therapy can be fully recommended. The success of surgery has been well documented; however, surgery is invasive and costly and carries potential side effects. Patients who report stable disease that has been present for longer than 12 months and who experience penile deformity preventing satisfactory sexual intercourse are best suited for surgery. Additionally, failed conservative management and a patient's preference for definitive correction are important additional indications for surgical treatment.

Effectiveness of antioxidants (propolis, blueberry, vitamin E) associated with verapamil in the medical management of Peyronie's disease: a study of 151 cases

A total of 151 patients (age: 24–74 years, mean: 55 ± 10.3) diagnosed with Peyronie's disease were enrolled in a non-surgical treatment. In addition to medical histories and physical examinations, all patients underwent the following tests: penile ultrasound, IIEF questionnaire and photographic documentation. The penile curvature was measured by taking a photograph during maximum erection. All 151 patients were treated at different times and with different combinations of drugs, and afterwards, they were clinically studied and divided into five different treatment groups: 1st = verapamil (injection + iontophoresis) + vitamin E + topical diclofenac + blueberries; 2nd = verapamil (injection + iontophoresis) + vitamin E + topical diclofenac + propolis; 3rd = verapamil (injection) + vitamin E + topical Diclofenac; 4th = verapamil (iontophoresis) + vitamin E + topical diclofenac; 5th = verapamil (injection + iontophoresis) + topical diclofenac + blueberries + propolis. All patients were treated for 6 months after which they underwent the same follow-up tests as performed prior to the treatment. The following was achieved: group 1 had the most reduction in plaque size (−66.4%; p = 0.000), group 2 obtained the highest rate where penile curvature disappeared (24.5%; p = 0.019); the best results with reference to decrease in curvature angle were reached by the 2nd group (−14°) and group 1 obtained −9.6° (p = 0.000).

Review of non-surgical treatment options for Peyronie's disease

Non-surgical treatment of Peyronie's disease (PD) has come a long way since it was first described in 1743. A myriad of treatment options are currently available, including oral, intralesional and external energy therapies. The purpose of this article is to review the contemporary literature on non-surgical therapies for PD, and where possible, focus on randomized, placebo-controlled trials, as well as review the latest guidelines for the management of PD from the International Committee on Sexual Medicine, which conveyed its findings in July 2009. At this time, it appears that a combination of oral agents and/or intralesional injection with traction therapy may provide a synergy between the chemical effects of the drugs and the mechanical effects of traction. Until a reliable treatment emerges, it does appear that some of the non-surgical treatments discussed can be used to stabilize the scarring process and may result in some reduction of deformity with improved sexual function.

Modern views on amlodipine and new S-amlodipine medications

The review presents the latest evidence on the calcium antagonist amlodipine, summarizing its mechanisms of action, its pleiotropic, endothelial function-related effects, and its anti-atherogenic activity. Amlodipine suppresses the proliferation of vascular smooth myocytes and extracellular matrix and improves endothelial vasodilatation, despite the absence of L-type calcium channels in these cells. This mechanism is related to an increase in endothelial nitric oxide (NO) release. The results of experimental studies on the role of S and R amlodipine isomers in its hemodynamic and pleiotropic activity are presented. While S-amlodipine is a pharmacologically active blocker of L-type calcium channels, R-amlodipine increases endothelial NO release. New medications have been developed, based on S-amlodipine. It has been shown that S-amlodipine 5 mg/d is bioequivalent to amlodipine 10 mg/d. The pharmacodynamics analysis demonstrated that S-amlodipine 5 mg/d and amlodipine 10 mg/d did not differ significantly in terms of mean levels of systolic and diastolic blood pressure, or mean heart rate. S-amlodipine was better tolerated and characterised by a lower incidence of peripheral edema than amlodipine. However, the effects of S-amlodipine on hard end-points should be investigated in the long-term prospective studies.

Current status and new developments in Peyronie's disease: medical, minimally invasive and surgical treatment options

INTRODUCTION

Peyronie's disease (PD) is a wound-healing disorder of the tunica albuginea of the penis which affects 3-9% of adult males. Clinically, any combination of plaque formation, penile pain, angulation and erectile dysfunction may appear. This condition may progress, stabilize or, uncommonly, regress during the initial acute phase (6-18 months).

AREAS COVERED

Information regarding this review was searched in PubMed until August 2010. Vitamin E, paraaminobenzoate and colchicine are sparingly employed oral medical therapies. Intralesional injections as a minimally invasive therapy for PD includes injection with verapamil, interferon-α-2b, and collagenase. Men suffering with PD who have significant penile deformity precluding successful coitus can be appraised for surgical correction. Surgery is considered the gold standard and includes plication, incision and grafting- or penile-prosthesis-related procedures.

EXPERT OPINION

This paper provides a broad overview of the subject of PD, available nonsurgical options and surgical approaches that will aid in the routine clinical diagnosis and management of PD. Increased public and medical awareness of PD prevalence, presentation, diagnosis and treatment options will serve well the large population of men who suffer in silence with this common condition.

Peyronie's disease: perspectives on therapeutic targets

INTRODUCTION

Peyronie's disease (PD) is an acquired benign connective tissue disorder of the penis, characterized by the development of fibrotic plaques, that can cause different degrees of bending, narrowing or shortening. Medical treatment for PD remains a major challenge. Impressive progress in our understanding of the molecular mechanisms of PD pathogenesis has uncovered several promising molecular targets for antifibrotic treatments.

AREAS COVERED

This review covers the literature pertaining to the exploration of therapeutic targets for PD. The search included: i) a MEDLINE search from 1941 to January 2011, limited to English-language medical literature, ii) relevant abstracts from 2009 and 2010, iii) relevant textbooks and iv) a pipeline search for therapeutics in development.

EXPERT OPINION

Rapid translational research depends on our ability to develop rational therapies targeted to penile tunical fibrosis, which necessitate a sound knowledge of the biology, biochemistry and the physiological role of fibroblasts, myofibroblasts and stem cells in PD. Much remains to be learned about the pathogenesis of PD. Although there are many interesting therapeutic targets, we are confronted with some questions when identifying new targets, or when validating potential therapeutic options.

Extracellular matrix molecules: potential targets in pharmacotherapy

The extracellular matrix (ECM) consists of numerous macromolecules classified traditionally into collagens, elastin, and microfibrillar proteins, proteoglycans including hyaluronan, and noncollagenous glycoproteins. In addition to being necessary structural components, ECM molecules exhibit important functional roles in the control of key cellular events such as adhesion, migration, proliferation, differentiation, and survival. Any structural inherited or acquired defect and/or metabolic disturbance in the ECM may cause cellular and tissue alterations that can lead to the development or progression of disease. Consequently, ECM molecules are important targets for pharmacotherapy. Specific agents that prevent the excess accumulation of ECM molecules in the vascular system, liver, kidney, skin, and lung; alternatively, agents that inhibit the degradation of the ECM in degenerative diseases such as osteoarthritis would be clinically beneficial. Unfortunately, until recently, the ECM in drug discovery has been largely ignored. However, several of today's drugs that act on various primary targets affect the ECM as a byproduct of the drugs' actions, and this activity may in part be beneficial to the drugs' disease-modifying properties. In the future, agents and compounds targeting directly the ECM will significantly advance the treatment of various human diseases, even those for which efficient therapies are not yet available.