Peyronie's disease cell culture models: phenotypic, genotypic and functional analyses

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

INTRODUCTION

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

AIM

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

METHODS

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

MAIN OUTCOME MEASURES

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

CONCLUSIONS

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

Pentoxifylline attenuates transforming growth factor-β1-stimulated collagen deposition and elastogenesis in human tunica albuginea-derived fibroblasts part 1: impact on extracellular matrix

INTRODUCTION

Transforming growth factor-β1 (TGF-β1) has been implicated in the pathogenesis of Peyronie's disease (PD) and also plays a role in collagen and elastin metabolism. Pentoxifylline (PTX) antagonizes the effects of TGF-β1 and has been utilized in our clinic for the management of PD.

AIM

We studied the effects of TGF-β1 and PTX on collagen metabolism and elastogenesis in tunica albuginea-derived fibroblasts (TADFs).

METHODS

TADFs from men with and without PD were cultured and treated with TGF-β1 and PTX as monotherapy at differing concentrations and time points. Combination treatment (TGF-β1 followed by PTX and vice versa) was also investigated.

MAIN OUTCOME MEASURES

Cell proliferation assay, enzyme-linked immunosorbent assay, and immunohistochemistry were utilized to assess the impact of TGF-β1 and PTX on TADF with respect to elastin and collagen I metabolism.

RESULTS

PTX inhibited fibroblast proliferation at doses of 100 µM. TGF-β1 stimulated elastogenesis and collagen I fiber deposition in TADF in a dose- and time-dependent fashion. Pretreatment with PTX dramatically attenuated TGF-β1-mediated elastogenesis and collagen fiber deposition in TADF from men with and without PD. Interestingly, production of collagen I was higher in untreated Peyronie's tunica (PT) cells relative to normal tunica (NT) cells; furthermore, PTX attenuated collagen production to levels similar to untreated control TADF in PT cells but not in NT cells, suggesting important intrinsic differences between PT and NT cells.

CONCLUSION

Both elastin and collagen are upregulated by TGF-β1 in TADF. This likely contributes to the PD phenotype. Pretreatment with PTX attenuates both collagen fiber deposition and elastogenesis in TADF exposed to TGF-β1; these effects suggest a useful role for PTX in the management of PD.

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

INTRODUCTION

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The chronology of depression and distress in men with Peyronie's disease

INTRODUCTION

For the practicing clinician, appreciating Peyronie's disease (PD) significant negative psychological impact is apparent. Despite this, there exists not a single study using validated instruments assessing this issue.

AIMS

To document the effect of PD on the psychosocial status of men.

MAIN OUTCOME MEASURES

The Center for Epidemiological Studies Depression scale (CES-D) for evaluation of depression and the SF-36 for quality of life assessment.

METHODS

Men (N = 92; 54 +/- 11 years of age) presenting for PD evaluation completed the CES-D, Short Form-36 (SF-36), and an inventory regarding PD. Partners were not assessed.

RESULTS

A vast majority of men (88%) had a partner with a mean partner age of 49 +/- 11 years. The median duration of PD at presentation was 12 (1-360) months. As a whole, 48% were classified as depressed on the CES-D (26% moderate, 21% severe). These subjects were then placed into groups according to the length of time since diagnosis of PD. Length-of-time groups were: 0-6 months, 6-12 months, 12-18 months, and >18 months. The percent of men scoring above the CES-D cutoff for depression remained consistently high with no significant difference across time since diagnosis groups. These results are supported by data from the Mental Health subscale (MHS) of the SF-36 (lower scores indicate lower mental heath). For the entire sample, the MHS standardized mean of 46.80 was significantly lower (P < 0.05) than the general male population standardized mean of 50. The MHS means stayed consistently low (no statistical difference) across time since diagnosis groups.

CONCLUSIONS

Using validated instruments, we have demonstrated that 48% of men with PD have clinically meaningful depression that would warrant medical evaluation. This high level of depression stayed consistent across time since diagnosis. These data suggest that most men do not psychologically adjust to their diagnosis of PD and all men with PD should be considered appropriate mental health screening.

Is There a Role for Proteomics in Peyronie's Disease?

INTRODUCTION

Peyronie's disease (PD) continues to be a major source of sexual dysfunction among the 3-9% of affected men. The challenge in treating PD is determining the natural history and clinical course for the individual patient. Currently, there exists no reliable means to predict whether a penile plaque of PD will progress, regress, or remain stable. This represents a significant deficiency in contemporary management, one that may be addressed with newer technologies such as proteomic profiling.

AIM

This review assesses the potential use of protein alterations measured by various novel technologies, to predict progression, regression, or stabilization of PD in an affected individual.

METHODS

A comprehensive literature review of the past decade in the field of gene profiling and protein expression of PD was performed.

MAIN OUTCOME MEASURES

A critical analysis of the existing worldwide literature evaluating surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF-MS or SELDI) and other proteonomic techniques.

RESULTS

SELDI and other technologies can provide the clinician with innovative data indicating the presence of unique individual factors that act to suppress or promote the fibrotic process in PD. Determining the clinical implications of altered protein expression in an individual is not yet defined.

CONCLUSIONS

The area of proteomics has begun to revolutionize the study of medicine in the postgenomic era, by allowing researchers to study the role that proteins play in health and disease. Applying this knowledge clinically has already led to innovative discoveries in early cancer detection in a number of malignancies, including prostate, ovarian, and bladder. Prior to the widespread use and acceptance of proteomic technology in PD, a critical assessment of its therapeutic and diagnostic value will be required.

Intralesional Verapamil Prevents the Progression of Peyronie’s Disease

OBJECTIVES

To define the impact of intralesional verapamil injection therapy on penile deformity in men with Peyronie's disease.

METHODS

Patients underwent a total of 6 intralesional injections of verapamil. Penile deformity was assessed at baseline and 3 months after the last intralesional injection of verapamil during penile erection after the administration of intracavernosal medication. Measurement was recorded using a goniometer at maximum penile rigidity. Endpoints included change in magnitude of curvature, stretched penile length, penetration ability, and resolution of pain.

RESULTS

Ninety-four consecutive patients met all inclusion criteria. Mean (+/- standard deviation) patient age and duration of Peyronie's disease at time of baseline deformity assessment were 44 +/- 18 years and 5.2 +/- 2.7 months, respectively. At baseline 86% had dorsal and 14% lateral curvature. The mean curvature and stretched flaccid length were 50 degrees +/- 28 degrees and 12.6 +/- 3.1 cm, respectively. At the follow-up evaluation, patients were 5.2 +/- 1.8 months after their last ILV injection and were 11.7 +/- 4.2 months after the onset of Peyronie's disease. Eighteen percent of patients had improvement of curvature, 60% were unchanged, and 22% worsened. Pain resolved in 100% of patients.

CONCLUSIONS

In response to intralesional verapamil, a minority of men experienced improvement in penile deformity; however, the majority of patients had stabilization of their deformity. This information may permit clinicians to give realistic expectations to patients considering intralesional verapamil therapy.

Pharmacological Management of Peyronie???s Disease

Peyronie's disease is a localised, fibrosing condition of the penis that occurs in up to 9% of men. Although its aetiology has not been elucidated, Peyronie's disease probably results from the presence of a predisposing genetic susceptibility combined with an inciting event, most probably trauma. Following appropriate clinical evaluation, initial treatment consists of a trial of oral and/or intralesional pharmacotherapy. Oral therapies most commonly employed include para-aminobenzoate (Potaba) and tocopherol (vitamin E), with colchicine, tamoxifen, propoleum and acetyl-L-carnitine being used less frequently. Placebo-controlled studies examining these agents have failed to show a consistent beneficial effect on Peyronie's disease, with the exception of para-aminobenzoate, which may decrease plaque size and curvature, and acetyl-L-carnitine, which may reduce erectile pain and inhibit disease progression. Intralesional injection therapy for Peyronie's disease is commonly used as a first-line therapy along with oral medications. The current standard of care involves injection with interferon-alpha-2a or -2b, verapamil or collagenase over 2-week intervals for a period of 5-6 months. Interferon-alpha-2b, in particular, has been documented in a large, multicentre, placebo-controlled study to be significantly more effective than placebo in decreasing penile curvature, plaque size, penile pain and plaque density. However, interferon treatment is also associated with significant adverse effects, including fever and other flu-like symptoms. Other available therapies that have not consistently shown efficacy in placebo-controlled studies include corticosteroids and orgotein. Surgery is considered in patients with Peyronie's disease who have not responded to a trial of conservative medical therapy for 1 year and who are precluded from sexual intercourse. Procedures commonly performed include the Nesbit procedure (or variations of the Nesbit), penile plaque incision/excision with or without grafting, and implantation of a penile prosthesis. Further basic scientific research in Peyronie's disease is likely to identify additional targets for future pharmacotherapy.

An analysis of the natural history of Peyronie's disease

PURPOSE

Little information exists on the natural history of PD. We defined the course of PD in a group of men with this condition who received no treatment.

MATERIALS AND METHODS

The study population comprised patients with PD who presented within 6 months of disease onset, had no medical treatment and were followed until at least 12 months after disease onset. At baseline and followup penile abnormality was determined following intracavernous injection and by measurement at maximum penile rigidity.

RESULTS

A total of 246 patients met inclusion criteria. At presentation mean age +/- SD was 52 +/- 22 years and the duration of PD was 3.5 +/- 1.5 months. At baseline in men with documented curvature 72% had dorsal, 17% had ventral and 11% had lateral curvature. Mean curvature at baseline was 42 +/- 22 degrees. Mean stretched flaccid penile length was 12.2 cm. The mean duration of PD at the followup assessment was 18 +/- 7 months. At followup stretched flaccid length had decreased to 11.4 cm (p = 0.035). Of the patients 32% complained of some degree of erectile dysfunction at baseline. All patients who reported penile pain had improvement and 89% reported complete resolution at followup. Of men with curvature 12% had improved, 40% remained stable and 48% had worsened at followup. In those in whom curvature improved the mean change was 15 degrees, while in those in whom curvature worsened the mean change was 22 degrees.

CONCLUSIONS

To our knowledge this is the largest study to explore the natural history of PD. A minority of men experienced improvement in penile abnormality, while penile length decreased during the 1-year followup. This information will permit clinicians to provide patients with realistic expectations at presentation for the evaluation of PD.

Identification of potential biomarkers of Peyronie's disease

AIM

To identify proteins that are differentially expressed in cells derived from normal and diseased tunica albuginea (TA) as related to Peyronie's disease (PD).

METHODS

Cells with characteristics of fibroblasts were isolated from two tissue sources. Those from the plaque of patients with PD were designated as PT cells, and those from the normally-appearing TA of the same patients were designated as NT cells. Messenger RNAs of these cells were analyzed by real-time polymerase chain reaction (RT-PCR) for the expression of monocyte chemoattractant protein 1 (MCP-1). Crude protein lysates were analyzed by surface-enhanced laser desorption/ionization mass spectrometry (SELDI-MS) with IMAC30-Cu, CM10, and H50 chips. Each lysate was then separated into six fractions, which were further analyzed by SELDI-MS.

RESULTS

RT- PCR analysis showed that PT cells expressed higher levels of MCP-1 than their counterpart NT cells. SELDI-MS analysis showed that the crude protein lysates of all four cell strains produced similar and reproducible protein profiles on IMAC30-Cu and CM10 chips. Additional SELDI-MS analyses with the fractionated lysates detected three proteins of 11.6 kDa, 14.5 kDa, 22.6 kDa that were upregulated in PT cells and two proteins of 6.3 kDa and 46.9 kDa that were downregulated in PT cells.

CONCLUSION

MCP-1, which is often involved in tissue fibrosis, was expressed at higher levels in PT than that in NT cells. Five potential biomarkers for PD were identified by SELDI-MS analysis.

Peyronie's disease: the epidemiology, aetiology and clinical evaluation of deformity

There is a wide variety of topics covered in this section. The epidemiology, aetiology and clinical evaluation of the deformity in Peyronie's disease is described, followed by a discussion of recent advances in the biology of diabetes-associated bladder complications. Bladder cancer and its molecular prognostic factors are presented, and the section ends with an in-depth presentation of an evidence-based approach to the understanding of the pharmacological class effect in the management of prostatic diseases.

Potassium paraaminobenzoate (POTABA) in the treatment of Peyronie's disease: a prospective, placebo-controlled, randomized study

PURPOSE

The aim of this study was to investigate the effect of potassium paraaminobenzoate (Potaba) in Peyronie's disease in a prospective, randomized, double-blind, placebo-controlled, multicentre study during a 12-months period of treatment.

PATIENTS AND METHODS

103 patients with Peyronie's disease and a history <12 months, non-calcified plaques and without pre-treatment were included. 51 were randomized to potassium paraaminobenzoate, 52 to placebo receiving 4 x 3g/day for 12 months. Follow-up was performed during the treatment period. Response has been defined as regression in plaque-size and/or reduction in penile curvature of at least 30%. Data analysis was focussed on 75 patients who completed the study [valid-cases (VC)].

RESULTS

No severe adverse events occurred. Response rates were 74.3% on potassium paraaminobenzoate and 50.0% on placebo (p=0.016). Mean plaque-size decreased from 259 mm(2) to 142 mm(2) in the treatment arm. In the placebo group, plaque-size aggravated from 259 mm(2) to 303 mm(2) after 6 months but improved slightly to 233 mm(2) after 12 months. Differences between the groups were significant (p=0.042). Pre-existing curvature did not improve under the drug (p=0.066) but comparing the development of new curvature or deterioration of pre-existing curvature under potassium paraaminobenzoate penile deviation remained stable. However, under placebo penile curvature deteriorated significantly in 32.5% of the cases (p<0.001). No significant differences concerning decrease of pain could be observed between the two groups (82.6% vs. 77.3%).

CONCLUSIONS

The results of this study indicate a significant plaque-related effect of potassium paraaminobenzoate. There was no relevant difference with regard to improvement of pre-existing penile deviation. However, under potassium paraaminobenzoate a significant protective effect on deterioration of penile curvature could be demonstrated. Potassium paraaminobenzoate appears to be useful to stabilize the disorder and prevent progression of penile curvature.

Alpha-1-Antitrypsin Levels and Genetic Variation of the Alpha-1-Antitrypsin Gene in Peyronie’s Disease

OBJECTIVES

Alpha-1-antitrypsin (alpha1-antitrypsin) is a major protease inhibitor controlling tissue degradation. Reduced alpha1-antitrypsin levels could result in a change of collagen metabolism. Previous studies have described decreased alpha1-antitrypsin levels in patients with Peyronie's disease. However, only a small number of patients were analyzed, and the reason for the decreased alpha1-antitrypsin levels remained unclear. This study investigated prospectively the levels of alpha1-antitrypsin in patients with Peyronie's disease, as well as genetic variation in the coding region of the alpha1-antitrypsin gene.

METHODS

Alpha1-antitrypsin levels were determined prospectively in 94 patients with Peyronie's disease and compared to healthy controls. Analysis of the alpha1-antitrypsin gene (S, Z variants; single nucleotid polymorphisms [SNPs]: T-395A, M2, M3, G6118A) was done in 141 Peyronie's patients including 43 patients with investigated alpha1-antitrypsin serum levels and compared to healthy controls.

RESULTS

In patients with Peyronie's disease, the alpha1-antitrypsin levels seemed to be decreased significantly compared to healthy controls. However, in the age matched approach no significant differences occurred. Moreover, a significant (p < 0.002) decrease of the alpha1-antitrypsin level with increasing age was observed, explaining the initial differences between the two groups. In confirmation with these findings, no significant association of the alpha1-antitrypsin gene variants with Peyronie's disease was detectable.

CONCLUSIONS

The results of this study do not indicate a significant association between Peyronie's disease and decreased alpha1-antitrypsin levels. Low alpha1-antitrypsin levels in Peyronie's patients are, rather, an age-related phenomenon, as revealed by the comparison with aged matched healthy controls. The decrease of the alpha1-antitrypsin serum level with increasing age has not been described before.

L-arginine and phosphodiesterase (PDE) inhibitors counteract fibrosis in the Peyronie's fibrotic plaque and related fibroblast cultures

Inducible nitric oxide synthase (iNOS) is expressed in both the fibrotic plaque of Peyronie's disease (PD) in the human, and in the PD-like plaque elicited by injection of TGFbeta1 into the penile tunica albuginea (TA) of the rat. Long-term inhibition of iNOS activity, presumably by blocking nitric oxide (NO)- and cGMP-mediated effects triggered by iNOS expression, exacerbates tissue fibrosis through an increase in: (a) collagen synthesis, (b) levels of reactive oxygen species (ROS), and (c) the differentiation of fibroblasts into myofibroblasts. We have now investigated whether: (a) phosphodiesterase (PDE) isoforms, that regulate the interplay of cGMP and cAMP pathways, are expressed in both the human and rat TA; and (b) L-arginine, that stimulates NOS activity and hence NO synthesis, and PDE inhibitors, that increase the levels of cGMP and/or cAMP, can inhibit collagen synthesis and induce fibroblast/myofibroblast apoptosis, thus acting as antifibrotic agents. We have found by immunohistochemistry, RT/PCR, and Western blot that PDE5A-3 and PDE4A, B, and D variants are indeed expressed in human and rat normal TA and PD plaque tissue, as well as in their respective fibroblast cultures. As expected, in the PD fibroblast cultures, pentoxifylline (non-specific cAMP-PDE inhibitor) increased cAMP levels without affecting cGMP levels, whereas sildenafil (PDE5A inhibitor) raised cGMP levels. Both agents and L-arginine reduced the expression of collagen I (but not collagen III) and the myofibroblast marker, alpha-smooth muscle actin, as determined by immunocytochemistry and quantitative image analysis. These effects were mimicked by incubation with 8-Br-cGMP, which in addition increased apoptosis, as measured by TUNEL. When L-arginine (2.25 g/kg/day), pentoxifylline (10 mg/kg/day), or sildenafil (10 mg/kg/day) was given individually in the drinking water for 45 days to rats with a PD-like plaque induced by TGF beta1, each treatment resulted in a 80-95% reduction in both plaque size and in the collagen/fibroblast ratio, as determined by Masson trichrome staining. Both sildenafil and pentoxiphylline stimulated fibroblast apoptosis within the TA. Our results support the hypothesis that the increase in NO and/or cGMP/cAMP levels by long-term administration of nitrergic agents or inhibitors of PDE, may be effective in reversing the fibrosis of PD, and more speculatively, other fibrotic conditions.

Functional Tissue Engineering of Autologous Tunica Albuginea: A Possible Graft for Peyronie’s Disease Surgery

OBJECTIVES

The aim of the present study was to generate a tissue engineered type of mechanically stable graft suitable for surgical replacement of the tunica albuginea penis.

METHODS

Porcine fibroblasts isolated from open fascia biopsies were seeded on decellularized collagen matrices and then cultivated in a bioreactor under continuous multiaxial stress for up to 21 days (n=12). Static cultures without mechanical stress served as controls. Cell proliferation, cell alignment, and de novo synthesis of extracellular matrix proteins (proteoglycans, procollagen I, elastin) in these grafts was evaluated by hematoxylin-eosin, pentachrome, and immuno-staining. Additionally, the enzymatic isolation of porcine fibroblasts from X4mm skin punch biopsies (n=8) was evaluated.

RESULTS

Mechanically strained cultures of fibroblasts showed a homogeneous multilayer matrix infiltration and a regular cell alignment in the direction of strain axis after 7 days, as well as a de novo production of extracellular matrix proteins compared to the static control. A large amount of viable fibroblasts was easily obtained from small skin punch biopsies.

CONCLUSION

This study shows that continuous multiaxial stimuli improve proliferation and extracellular matrix synthesis of mature fibroblasts reseeded on a biological matrix making this a feasible autologous tissue engineered graft for penile surgery. For the clinical setting fibroblasts harvested from small skin biopsies can be a comfortable cell source.

Chromosomal instability is demonstrated by fibroblasts derived from the tunica of men with Peyronie's disease

Peyronie's disease is a fibrotic disorder, a condition characterized by cellular proliferation and excess extracellular matrix production. Previous work in related conditions has demonstrated chromosomal instability. This investigation was undertaken to analyze fibroblasts derived from Peyronie's disease tunical tissue for abnormalities of chromosome number and progression of cytogenetic aberrations during cell culture. Tunical tissue was excised from men with Peyronie's disease from both plaque and nonplaque tissue and cells were explanted in culture. Control cells were derived from both neonatal foreskins and normal tunica from men with congenital penile curvature. Fluorescent in situ hybridization was used to probe for chromosomes 7, 8, 17, 18, X and Y. Control cells demonstrated normal copy number for all chromosomes analyzed. In contrast, Peyronie's disease plaque-derived fibroblasts demonstrated frequent aneusomies in chromosomes 7, 8, 17, 18 and X and recurrent deletions of chromosome Y. Peyronie's disease nonplaque tunica-derived fibroblasts demonstrated infrequent chromosomal changes early in culture; however, with repeated passaging the majority of cell cultures demonstrated aneusomies in at least one chromosome. These data indicate that Peyronie's disease plaque-derived fibroblasts have consistent aneusomies even at early passage and that nonplaque tunica-derived cells from men with Peyronie's disease also demonstrate chromosomal instability. This suggests that the tunica albuginea of men with Peyronie's disease may be predisposed to undergoing unregulated fibrosis. These findings confirm the transformed nature of the Peyronie's disease tunical fibroblasts studied in this analysis. While the etiology of these findings is not clear, it is likely that these pathobiological characteristics contribute to the pathophysiology of this disease process.

The management of Peyronie's disease

Peyronie's disease has no known cause; recent understanding of the molecular mechanisms involved and the development of an animal model will aid the medical management of early disease. The medical management of chronic disease is futile as the delicate tunical architecture cannot regenerate. Surgical correction of the penile deformity is required in a minority of patients, and a choice lies between a Nesbit operation and a plaque incision and venous patch in patients who are concerned with penile shortening.

Wogonin suppresses cellular proliferation and expression of monocyte chemoattractant protein 1 in Peyronie's plaque-derived cells

OBJECTIVE

To test the effect of wogonin on cellular proliferation and expression of monocyte chemoattractant protein 1 (MCP-1) in cells derived from normal and diseased tunica albuginea (TA), as related to Peyronie's disease (PD).

MATERIALS AND METHODS

Cells with characteristics of fibroblasts were isolated from three tissue sources. Those from the plaque of patients with PD were designated as P cells, those from the adjacent, normal-appearing tissue as C cells, and those from the TA of patients without PD as N cells. These cells were treated with wogonin at doses of 0, 10, 20 and 40 micromol/L for 24 h or treated at a fixed dose of 40 micromol/L for 1, 8 and 24 h. Cell proliferation was assayed with a commercial kit, MCP-1 mRNA expression by reverse transcription-polymerase chain reaction, and secreted MCP-1 by enzyme-linked immunosorbent assay.

RESULTS

Wogonin suppressed cell proliferation in a dose-dependent manner; the effect was more pronounced against P cells at 8 and 24 h. Wogonin down-regulated MCP-1 mRNA expression, especially in P cells. Wogonin suppressed the level of secreted MCP-1 by 59-88%. P cells, which secreted far more MCP-1 than N and C cells at 1 h, were suppressed by 88%. C cells were the least suppressed at all three times.

CONCLUSIONS

Wogonin suppressed the proliferation, the expression of MCP-1 mRNA, and the expression of secreted MCP-1 in TA-derived cells. In most cases, the effect of wogonin was greatest against cells derived from the plaque. Wogonin appears to be a worthy candidate for preclinical trials in men with PD.