Androgen receptors in Dupuytren's contracture.

Palmar fascia tissue and cultured cells from patients with Dupuytren's contracture and from normal subjects were characterized and analyzed for androgen receptor expression. Androgen receptors have never been studied in Dupuytren's myofibroblasts and may have a role in its high male predominance. Surgical samples were collected from eight patients undergoing surgery for Dupuytren's contracture and from four patients with carpal tunnel syndrome, used as control tissue. Immunohistochemical analysis was performed on tissue samples and on cell cultures with anti-androgen receptor, anti-alpha-smooth muscle actin, anti-fibronectin, and anti-type I and III collagen antibodies using the biotin avidin peroxidase method as revelatory system. Immunostaining for androgen receptors in tissue samples and cultured cells revealed nuclear reaction in many Dupuytren's myofibroblasts, but in few fibroblasts of the normal palmar fascia. In a double-labeling study, androgen receptors were seen to co-localize with alpha-actin in both cell cultures and tissue samples. We present the first evidence that the palmar fascia is a target tissue for androgen action and that the expression of androgen receptors in Dupuytren's contracture is considerably higher than in the normal palmar fascia. Further studies will need to evaluate whether the androgen-responsive state of the tissue is related to the high incidence of Dupuytren's contracture in the male sex.     

Dupuytren's contracture. Fine structure in relation to aetiology

The fine structure of palmar fascia from patients with Dupuytren's contracture (DC) was compared with that from patients with carpal tunnel syndrome (CTS). In contrast to previous assumptions, the ultrastructure of fibroblasts both in vivo and in vitro from DC and CTS appeared identical, indicating that myofibroblasts are not specific to DC. The major differences between DC and CTS were: 1) a sixfold and fortyfold increase in fibroblast density in cord and nodular areas of DC compared with CTS; 2) a more disorganised pattern of collagen fibrils in DC; and 3) markedly narrowed microvessels surrounded by thickened, laminated basal laminae and proliferating fibroblasts in DC compared with CTS. To account for these morphological changes a hypothesis is presented which proposes that oxygen-free radicals cause pericytic necrosis and fibroblastic proliferation. This hypothesis provides a potential avenue for therapy of DC and other fibrotic conditions.     

The role of the fibroblast in Dupuytren's contracture.

Ultrastructural, immunohistochemical, and biochemical studies to date show that the fibroblast in Dupuytren's contracture is identical to palmar fascia fibroblasts in patients unaffected by Dupuytren's contracture, and to all other fibroblasts. The major difference relating to fibroblasts is that in Dupuytren's contracture there are more of them, and they are clustered around narrowed microvessels. It is probable that these two phenomena are linked because recent studies indicate a greater potential for ischemia-induced oxygen free radical generation in Dupuytren's contracture, and because oxygen free radicals in these concentrations can stimulate fibroblast proliferation. The major source of oxygen free radicals is likely to be from microvascular endothelial xanthine oxidase-catalyzed reactions. These observations also account for many of the epidemiologic associations of Dupuytren's contracture, because (1) age, race, and diabetes are associated with microvessel narrowing and (2) age, diabetes, alcohol consumption, HIV infection, cigarette smoking, and trauma are associated with increased free radical generation. Nonsteroidal anti-inflammatory drugs and allopurinol are two agents that decrease oxygen free radical release and may inhibit or prevent Dupuytren's contracture.     

Responsiveness of Dupuytren's disease fibroblasts to 5 alpha-dihydrotestosterone

PURPOSE: We recently showed that androgen receptors are expressed in Dupuytren's contracture. The aim of the present work was to test the responsiveness of Dupuytren's fibroblasts to 5 alpha-dihydrotestosterone (5 alpha-DHT), the active form of testosterone. RESULTS: Cultured palmar fascia cells from 10 patients with Dupuytren's contracture and 4 normal subjects were exposed to 5 alpha-DHT (10 or 100 ng/mL) for 1, 3, 7, and 15 days. Their phenotype was analyzed immunohistochemically for alpha-smooth muscle actin and androgen receptor expression and proliferation rates were studied. RESULTS: At 15 days the higher concentration of 5 alpha-DHT induced an increase in Dupuytren's fibroblast proliferation, whereas anti-alpha-smooth muscle actin exhibited the strongest expression. At the same time point androgen receptor expression decreased with the lower concentration and disappeared altogether with the higher dose of 5 alpha-DHT. CONCLUSIONS:The palmar fascia is a target tissue for androgen action via androgen receptors. Further studies are required to determine whether control of androgen receptor may control the evolution of Dupuytren's disease.     

The effect of steroids on Dupuytren's disease: role of programmed cell death

This study compared the rates of proliferation and apoptosis of cells within nodules of Dupuytren's disease and nodules from patients that had been injected preoperatively with steroid (Depo-Medrone). It also compared the effects of steroids in apoptosis in cultured Dupuytren's cells and control fibroblasts from palmar fascia and fascia lata. Steroids reduced the rate of fibroblast proliferation and increased the rate of apoptosis of both fibroblasts and inflammatory cells in Dupuytren's tissue. Steroids also produced apoptosis of cultured Dupuytren's cells but not of palmar fascia and fascia lata cells.     

Tamoxifen decreases fibroblast function and downregulates TGF(beta2) in dupuytren's affected palmar fascia

BACKGROUND: Dupuytren's contracture is a fibroproliferative disorder that is associated with increased collagen deposition. Isoforms of transforming growth factor beta (TGF(beta)), normally TGF(beta1) and TGF(beta2), are involved in the progressive fibrosis of Dupuytren's disease. It has been suggested that downregulation of TGF(beta) may be useful in the treatment of the condition. Tamoxifen, a synthetic nonsteroidal antiestrogen, is known to modulate the production of TGF(beta). This study examined the role of tamoxifen in decreasing fibroblast function and downregulating TGF(beta2). METHODS: Primary cultures of fibroblasts were obtained from Dupuytren's affected fascia and carpal tunnel affected fascia as a control. Collagen lattices were prepared and populated with the fibroblasts. The fibroblast-populated collagen lattices (FPCL) were then measured for contraction every 24 h for 5 days. Supernatant was obtained from the culture medium following completion of the FPCL portion of the experiment and used for a TGF(beta2) immunoassay. RESULTS: Dupuytren's affected fibroblasts contracted the FPCLs significantly more than carpal tunnel control fibroblasts. Treating the fibroblasts with tamoxifen caused a decreased contraction rate in both Dupuytren's affected fibroblasts and carpal tunnel controls. There was increased TGF(beta2) expression in the Dupuytren's affected fascia group compared to the carpal tunnel control group. Tamoxifen decreased TGF(beta2) expression in Dupuytren's affected fascia group but not in the carpal tunnel control group. CONCLUSION: TGF(beta) appears to be the key cytokine in the fibrogenic nature of Dupuytren's disease. Tamoxifen treatment has been demonstrated to decrease the function of fibroblasts derived from Dupuytren's affected fascia and downregulated TGF(beta2) production in these same fibroblasts. These data suggest a method to manipulate and control Dupuytren's contracture in the clinical setting.     

Dupuytren's contracture: morphological and biochemical changes in palmar aponeurosis

The palmar aponeurosis removed from ten patients with Dupuytren's contracture was studied using morphological and biochemical approaches. The histological characteristic of Dupuytren's contracture is the presence of numerous nodules among the lamellar structures of the collagen fibres. In the nodules, there are many active fibroblasts which are surrounded by immature fibres and metachromatic substances demonstrated by toluidine blue staining. Ultrastructurally, the active fibroblasts have the characteristics of myofibroblasts, as previously reported by Dr. Gabbiani. We found that some fibroblasts have intracellular collagen fibrils in the cytoplasm. When assayed by Siegel and Martin's method, lysyl oxidase activity of the palmar aponeurosis was significantly higher in Dupuytren's contracture than in normal hands. Biochemical studies such as electrophoretic analysis of mucopolysaccharides, determination of uronic acid and collagen contents were undertaken to compare the aponeurosis of Dupuytren's contracture with normal cases. The uronic acid contents were higher in Dupuytren's contracture than in the controls. However, no difference between the two groups was found in the collagen contents and in the composition of the mucopolysaccharides. These characteristic features; existence of myofibroblasts and intracellular collagen fibrils and increase in the activity of lysyl oxidase probably play a significant role in the establishment of flexion contracture of the fingers in Dupuytren's contracture.     

Enzymes of glucose metabolism in palmar fascia and Dupuytren's contracture.

Several enzymes participating in glucose metabolism and some of the acid hydrolases were assayed in palmar fascia and Dupuytren's contracture with fluorometric microanalytical methods. The enzyme activities of glucose metabolism were lower in normal palmar fascia than in dermis. The fascia of Dupuytren's contracture exhibited a general increase in the enzyme activities of glucose catabolism. Little alteration was found in alanine aminotransferase and UDP-glucose dehydrogenase activity in the lesion. Lysosomal hydrolytic enzyme activities were increased five to ten times in Dupuytren's tissue. The dermis overlying Dupuytren's contracture exhibited an increase in the enzyme activities of glucose catabolism, but to a lesser degree than did the fascia of the lesion. The epidermis of involved palmar skin displayed normal enzyme activities.     

The effect of 5-fluorouracil on Dupuytren fibroblast proliferation and differentiation

INTRODUCTION: Dupuytren's disease is a proliferative disease with contractile properties, prone to recur after surgery. Intra-operatively applied 5-fluorouracil has been used to avoid scar problems in the eye after glaucoma filtration surgery and was therefore investigated as a means to inhibit proliferation and myofibroblast differentiation in Dupuytren fibroblasts in vitro. METHOD: Primary cell lines were obtained by explants from Dupuytren's tissue (n = 6), non-diseased palmar fascia from patients with Dupuytren's disease (n = 3) and carpal ligament from patients undergoing carpal tunnel release (n = 3). The effect of 5-fluorouracil on proliferation was assessed by cell counting. Myofibroblast differentiation, an intergral part of Dupuytren's contracture, was investigated by staining for alpha smooth muscle actin, a marker for contractile cells, using immunohisto-chemical methods. RESULTS: A single exposure to 5-fluorouracil caused a sustained inhibition of proliferation in Dupuytren's and non-diseased fascia cultures, whilst the effect on carpal ligament cultures was transient. Untreated Dupuytren's fibroblasts exhibited the highest myofibroblast differentiation, whilst differentiation in non-diseased fascia cultures was shown to be proportional to cell density and virtually non-existent in carpal ligament cultures. After 5-fluorouracil exposure, the differentiation was significantly reduced in Dupuytren's fibroblasts cultures, reduced at high cell densities in non-diseased fascia and unchanged in carpal ligament cell cultures. DISCUSSION: 5-fluorouracil inhibits both proliferation and myofibroblast differentiation in Dupuytren's cell cultures and may have a potential use as an adjuvant treatment to Dupuytren surgery in order to reduce the rate of recurrence and contracture.     

Aetiology of Dupuytren's contracture

Dupuytren's contracture is a fascinating, deforming, fibrotic condition of the palmar fascia which has confounded clinicians and scientists for centuries. The aim of this paper is to place in perspective the longstanding associations of age, sex, race, hereditary factors, diabetes and alcohol consumption with the more recent novel investigations at the cellular level. In concert, the findings indicate that a number of factors may lead to the narrowing of palmar fascia microvessels, with localized ischaemia and oxygen free radical release. Oxygen free radicals are likely to damage the surrounding stroma, and stimulate fibroblast proliferation. Proliferating fibroblasts lay down collagen and contract in the lines of stress. The process is likely to encourage further microvessel ischaemia with a positive feedback effect that is consistent with the progressive nature of the condition.     

Pathogenesis of Dupuytren's contracture--a review]

Dupuytren's disease is a palmar fibromatosis bringing about irreversible finger contracture. Histopathologically, the disease is characterized by the presence of the two types of structures: nodules, containing of intensively proliferating cells, and fibrous cords, formed by thick bundles of collagen fibers. It seems that key role in the development of Dupuytren's contracture play alterations of palmar fibroblasts activity. These cells begin intensively proliferate and transform to myofibroblasts. The later ones sharing phenotypic features of fibroblasts and smooth muscle cells take part in remodelling of extracellular matrix and are a source of palmar contracture. The pivotal factors involved in changes of palmar fibroblasts functions seem to be growth factors (mainly TGF beta, PDGF and bFGF). However, the participation of reactive forms of oxygen in mentioned process is also considered.     

Fibrin/fibrinogen and fibrinolytic activity of the palmar fascia in Dupuytren's contracture

Considering the proved interaction of fibrin with fibroblasts and the seemingly decisive role of structural and functional changes ("modulation") of these cells in the evolution of Dupuytren's contracture, research has been carried out in order to investigate the fibrinolytic capacity and the possible presence of fibrin/fibrinogen in the palmar fascia of subjects operated upon for Dupuytren's Disease. Fibrin/fibrinogen were detected by a direct immunofluorescence technique and fibrinolytic activity was assessed by a fibrin plate method. A remarkable decrease of fibrinolytic activity and the presence of fibrin/fibrinogen were observed in small nodules in the early stage of disease, whereas large nodules showed a high amount of plasminogen activator enzymes. Small nodules seem to form and increase by progressive adhesion of fibroblasts to the polymerizing fibrin, while high fibrinolytic activity of large nodules probably results from "modulation" of many fibroblasts into contractile myofibroblasts and could therefore be considered as a biochemical sign of the evolutionary phase of Dupuytren's contracture.     

Gelatinase A activity in Dupuytren's disease

PURPOSE: Dupuytren's contracture is a fibroproliferative disorder of the hand characterized by an abnormal myofibroblast and fibroblast proliferation and extracellular matrix deposition leading to retraction and deformation of the palm. Recent studies have shown that molecules of extracellular matrix may coordinate morphogenesis, cell differentiation, and most importantly, fibrogenesis in tissue. Gelatinase A (MMP-2) is a member of the matrix metalloproteinase family of proteolytic enzymes that contribute to remodeling the extracellular matrix by degrading its components. The aim of this study was to determine the level of MMP-2 activation in the palmar fascia of patients with Dupuytren's contracture with reference to the clinical stages of disease progression and recurrence of the contracture after surgery. METHODS: The level of relative MMP-2 activation, expressed by the active to latent MMP-2 ratio, was investigated with use of zymography and computerized densitometry in 16 normal and 71 pathologic tissues characterizing different clinical stages of the disease progression. RESULTS: We found that the level of MMP-2 activation was significantly elevated in the palmar fascias with Dupuytren's contracture compared with normal tissues. We did not find statistically significant differences between groups with different stages of the disease progression. We also did not find a relation between a high level of MMP-2 activation and the recurrence in the area of surgically treated Dupuytren's contracture. CONCLUSIONS: The differences in MMP-2 activation between contractured and normal fascia suggest a participation of this enzyme in the promotion of Dupuytren's disease. We did not find a relationship, however, between the level of MMP-2 activation and the secondary contracture.     

Epidermal growth factor receptor (EGF-R) in Dupuytren's disease

The aim of this paper was to examine participation of the epidermal growth factor receptor (EGF-R) signal pathway in the pathogenesis of Dupuytren's disease. The study showed changes in the ratio of membrane EGF-R to its intracellular level during the different clinical stages of Dupuytren's contracture progression. Our observations of a high ratio of surface to intracellular EGF-R in the palmar aponeurosis of patients with second degree of Dupuytren's disease (Iselin's classification), which was significantly higher than this ratio in control palmar fascia (P=0.022), would suggest that EGF-R has a role in the involutional phase of the disease.     

Dupuytren's contracture: an update of biomolecular aspects and therapeutic perspectives

The so-called fibrogenic cytokines, able to induce the growth of fibroblasts and their differentiation into myofibroblasts and to stimulate their production of extracellular matrix, are involved in the genesis of Dupuytren's contracture. Although many studies have been made of biomolecular aspects of palmar fibromatosis, practical applications from them are still far from imminent because of the real difficulty of blocking their action in vivo, even in a chronic, progressive lesion such as Dupuytren's disease. Consequently, surgical excision of the palmar fascia still remains the treatment of choice.     

Elevated levels of β-catenin and fibronectin in three-dimensional collagen cultures of Dupuytren's disease cells are regulated by tension <Emphasis Type="Italic">in vitro</Emphasis>

Background  

Dupuytren's contracture or disease (DD) is a fibro-proliferative disease of the hand that results in the development of scar-like, collagen-rich disease cords within specific palmar fascia bands. Although the molecular pathology of DD is unknown, recent evidence suggests that β-catenin may play a role. In this study, collagen matrix cultures of primary disease fibroblasts show enhanced contraction and isometric tension-dependent changes in β-catenin and fibronectin levels.     

Langerhans cells in Dupuytren's contracture

We have examined biopsies of Dupuytren's contracture palmar fascia, overlying subcutis and skin, and have correlated the distribution of gross macroscopic changes in the hand, mapped pre- and intraoperatively, with light microscopic immunohistochemical findings. We report increased numbers of S100 positive Langerhans cells (an epidermal cell of dendritic lineage) and CD45 positive cells, both in "nodules" and at dermo-epidermal junctions, in the biopsied tissues. This suggests that Langerhans cells migrate from the epidermis into Dupuytren's contracture tissue, possibly in response to local changes in levels of inflammatory cytokines within the tissue. Our findings, together with other reports of increased numbers of dermal dendrocytes and inflammatory cells in Dupuytren's contracture tissue, lend circumstantial support to the "extrinsic theory" of the pathogenesis of Dupuytren's contracture. However, the earliest stages of the disease process have not been defined, and therefore the events which ultimately produce fibrosis in the palmar fascial complex in susceptible individuals could begin in the skin and/or within deeper tissues, especially where there is dysregulation of the immune system.     

Chromosomal abnormalities in Dupuytren's contracture and carpal tunnel syndrome.

The cytogenetics of cell cultures derived from Dupuytren's tissue, adjacent palmar fascia and palmar skin from patients undergoing fasciectomy have been examined and the results compared to cell cultures established from palmar fascia, flexor retinaculum and palmar skin of patients undergoing carpal tunnel decompression. Chromosomal abnormalities were detected in cell cultures from Dupuytren's tissue in eight of the nine patients studied. Clones of cells trisomic for chromosome 8 were found in five of the nine patients. Trisomy 8 was also present in two of five flexor retinaculum cultures from carpal tunnel syndrome cases. These findings in both Dupuytren's contracture and carpal tunnel syndrome suggest the presence of chromosomal instability in the palmar fascia. The significance of the chromosomal abnormalities is however unclear, but they indicate a possible common pathway in the onset of pathological fibrosis.     

Isolation and characterization of collagen in Peyronie's disease

Peyronie's disease is characterized histologically by excessive collagen deposition in the lesion. We examined the collagen types in Peyronie's disease plaque tissues compared to unaffected tissues from the same patient, other control tissues, and Dupuytren's contracture. Gel electrophoresis of pepsin-solubilized collagen demonstrated the presence of type I collagen and an increased content of type III collagen in plaque tissue. Increased type III collagen was detected in apparently normal tissue adjacent to the plaque and in Dupuytren's lesion, confirming previous findings. Although the cause of excessive collagen accumulation of Peyronie's disease is unknown, the results suggest an imbalance in the regulation of extracellular matrix production leading to pathologic fibrosis.