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1.
Ann Rheum Dis ; 70(1): 32-8, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20805294

ABSTRACT

OBJECTIVES: Ischaemic digital ulcers (DUs) are common in patients with systemic sclerosis (SSc) and are a cause of disease-related morbidity. In an earlier trial, treatment with bosentan, an oral endothelin receptor antagonist, reduced the occurrence of new DUs by 48%. The present study (RAPIDS-2, for 'RAndomized, double-blind, Placebo-controlled study with bosentan on healing and prevention of Ischemic Digital ulcers in patients with systemic Sclerosis') was conducted to more fully evaluate the effects of bosentan treatment on DUs associated with SSc. METHODS: This double-blind, placebo-controlled trial conducted at 41 centres in Europe and North America randomised 188 patients with SSc with at least 1 active DU ('cardinal ulcer') to bosentan 62.5 mg twice daily for 4 weeks and 125 mg twice daily thereafter for 20 weeks (n=98) or matching placebo (n=90; total 24 weeks). The two primary end points were the number of new DUs and the time to healing of the cardinal ulcer. Secondary end points included pain, disability and safety. RESULTS: Over 24 weeks, bosentan treatment was associated with a 30% reduction in the number of new DUs compared with placebo (mean ± standard error: 1.9±0.2 vs 2.7±0.3 new ulcers; p=0.04). This effect was greater in patients who entered the trial with more DUs. There was no difference between treatments in healing rate of the cardinal ulcer or secondary end points of pain and disability. Peripheral oedema and elevated aminotransferases were associated with bosentan treatment. CONCLUSIONS: Bosentan treatment reduced the occurrence of new DUs in patients with SSc but had no effect on DU healing. Bosentan was well tolerated and may be a useful adjunct in the management of patients with SSc with recurrent DUs.


Subject(s)
Fingers/blood supply , Hand Dermatoses/drug therapy , Scleroderma, Systemic/complications , Skin Ulcer/drug therapy , Sulfonamides/therapeutic use , Adult , Bosentan , Double-Blind Method , Drug Administration Schedule , Endothelin Receptor Antagonists , Female , Hand Dermatoses/etiology , Hand Dermatoses/prevention & control , Humans , Male , Middle Aged , Skin Ulcer/etiology , Skin Ulcer/prevention & control , Sulfonamides/administration & dosage , Sulfonamides/adverse effects , Treatment Outcome , Wound Healing
2.
Arthritis Rheum ; 60(4): 1102-11, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19333948

ABSTRACT

OBJECTIVE: A phase II randomized controlled trial of recombinant human relaxin suggested that a dosage of 25 microg/kg/day was safe and clinically effective in improving skin disease and reducing functional disability in scleroderma (systemic sclerosis; SSc). We undertook a large randomized, double-blind, placebo-controlled clinical trial to compare placebo with 10 microg/kg/day and 25 microg/kg/day recombinant human relaxin, given for 24 weeks in patients with stable, diffuse, moderate-to-severe SSc. METHODS: Men and women ages 18-70 years with diffuse cutaneous SSc (dcSSc) were administered recombinant human relaxin (10 microg/kg/day or 25 microg/kg/day) or placebo for 24 weeks as a continuous subcutaneous infusion. There was a followup safety visit at week 28. RESULTS: The primary outcome measure, the modified Rodnan skin thickness score, was similar among the 3 groups at baseline and at weeks 4, 12, and 24. Secondary outcomes such as functional disability were similar in all 3 groups, while the forced vital capacity decreased significantly in the relaxin groups. The discontinuation of both doses of relaxin at week 24 led to statistically significant declines in creatinine clearance and serious renal adverse events (defined as doubling of serum creatinine, renal crisis, or grade 3 or 4 essential hypertension) in 7 patients who had received relaxin therapy but in none who had received placebo. CONCLUSION: Recombinant relaxin was not significantly better than placebo in improving the total skin score or pulmonary function or in reducing functional disability in patients with dcSSc. In addition, relaxin was associated with serious renal adverse events, the majority of which occurred after stopping the infusion. If relaxin is used therapeutically for any conditions other than scleroderma, close monitoring of blood pressure and renal function must be performed.


Subject(s)
Relaxin/administration & dosage , Relaxin/adverse effects , Scleroderma, Systemic/drug therapy , Adult , Creatinine/metabolism , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , Infusions, Subcutaneous , Male , Middle Aged , Placebos , Recombinant Proteins/administration & dosage , Recombinant Proteins/adverse effects , Scleroderma, Systemic/pathology , Skin/pathology , Substance Withdrawal Syndrome , Treatment Failure , Vital Capacity/drug effects
3.
Arthritis Rheum ; 59(5): 699-705, 2008 May 15.
Article in English | MEDLINE | ID: mdl-18438905

ABSTRACT

OBJECTIVE: To determine the validity, reliability, and feasibility of durometer measurements of skin hardness as an outcome measure in clinical trials of scleroderma. METHODS: Skin hardness was measured during a multicenter treatment trial for scleroderma using handheld digital durometers with a continuous scale. Skin thickness was measured by modified Rodnan skin score (MRSS). Other outcome data collected included the Scleroderma Health Assessment Questionnaire. In a reliability exercise in advance of the trial, 9 investigators examined the same 5 scleroderma patients by MRSS and durometry. RESULTS: Forty-three patients with early diffuse cutaneous systemic sclerosis were studied at 11 international centers (mean age 49 years [range 24-76], median disease duration 6.4 months [range 0.3-23], and median baseline MRSS 22 [range 11-38]). The reliability of durometer measurements was excellent, with high interobserver intraclass correlation coefficients (ICCs) (0.82-0.92), and each result was greater than the corresponding skin site ICCs for MRSS (0.54-0.85). Baseline durometer scores correlated well with MRSS (r = 0.69, P < 0.0001), patient self-assessments of skin disease (r = 0.69, P < 0.0001), and Health Assessment Questionnaire (HAQ) disability scores (r = 0.34, P = 0.03). Change in durometer scores correlated with change in MRSS (r = 0.70, P < 0.0001), change in patient self-assessments of skin disease (r = 0.52, P = 0.003), and change in HAQ disability scores (r = 0.42, P = 0.017). The effect size was greater for durometry than for MRSS or patient self-assessment. CONCLUSION: Durometer measurements of skin hardness in patients with scleroderma are reliable, simple, accurate, demonstrate good sensitivity to change compared with traditional skin scoring, and reflect patients' self-assessments of their disease. Durometer measurements are valid, objective, and scalable, and should be considered for use as a complementary outcome measure to skin scoring in clinical trials of scleroderma.


Subject(s)
Scleroderma, Systemic/pathology , Skin/pathology , Adult , Aged , Double-Blind Method , Feasibility Studies , Female , Humans , Male , Middle Aged , Observer Variation , Reproducibility of Results , Sensitivity and Specificity , Skinfold Thickness , Surveys and Questionnaires
4.
J Rheumatol ; 34(3): 501-9, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17299843

ABSTRACT

OBJECTIVE: To obtain a consensus on the minimal clinically relevant treatment effect in various scleroderma disease outcome measures to be used in future clinical trials. METHODS: A Delphi consensus building exercise using a survey was sent out to members of the Scleroderma Clinical Trials Consortium (SCTC). The 65 SCTC members were divided into 2 groups. Group 1 was informed, in a cover letter, of the usual American College of Rheumatology 20% response results in randomized trials using effective biologic treatments for rheumatoid arthritis, while Group 2 was not. The first round of the exercise presented the scleroderma experts with a survey composed of 95 questions/clinical scenarios divided into 8 categories. These included situations where the treatment group improved, or worsened, or where some outcome measures improved, while others worsened. From the responses of this first round, a mean, mode, median, and range of responses for each of the 95 questions was obtained. This information was sent out, in the second round of the Delphi exercise, only to those respondents who answered the first round. The respondent's previous answer and the mean and range from the first round were provided for each question. It gave respondents the option to change any of their initial responses. The median of their responses in the second round was used to calculate the values for the minimal clinically relevant treatment effect. RESULTS: Thirty-two of the 65 SCTC members returned the first round of the Delphi exercise. Twenty-eight members returned the second round. Intraclass correlation coefficients between responses to round 1 and 2 were calculated for the questions. These varied from 0.99 (excellent agreement) to 0.02 (poor agreement). The p value was under 0.09 for 9 questions and under 0.19 for 20 questions. Standard deviations (SD) were calculated and were found to be lesser for each of the questions in round 2 when compared to the SD in responses from round 1, thus indicating a movement towards a consensus by the second round. An average of 33% of the responses were changed by the respondents in the second round of the Delphi exercise to a value closer to the median/average of the first round's responses. A range in required values for the minimal clinically relevant treatment effect for Modified Rodnan skin score is 3 to 7.5 units, Health Assessment Questionnaire Disability Index (HAQ-DI) 0.2 to 0.25 units, HAQ pain 0.2 to 0.3 units, MD global (100 mm visual analog scale) 8 to 13, patient global assessment 10 to 12, and diffusing capacity (percentage predicted) 9 to 10. The scenarios were especially weighted towards overall disease modification, thus organ-specific measures, such as 6 minute walk time (which has been used in many pulmonary artery hypertension trials), forced vital capacity, and a dyspnea rating (which may be important in scleroderma lung trials), were not included in the survey. CONCLUSION: Our study begins to address the current deficiency in our knowledge of appropriate values for the minimal clinically relevant treatment effect in various scleroderma disease outcome measures. A consensus could be achieved, or at least a range of minimal clinically relevant treatment effect values could be found for several outcome measurements. Of course, this consensus statement will be modified by evidence as it accrues in each consensus area.


Subject(s)
Delphi Technique , Outcome Assessment, Health Care/standards , Scleroderma, Systemic/therapy , Treatment Outcome , Clinical Trials as Topic , Disabled Persons , Endpoint Determination , Health Status , Humans , Rheumatology/standards
5.
Arthritis Rheum ; 56(1): 323-33, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17195236

ABSTRACT

OBJECTIVE: To evaluate CAT-192, a recombinant human antibody that neutralizes transforming growth factor beta1 (TGFbeta1), in the treatment of early-stage diffuse cutaneous systemic sclerosis (dcSSc). METHODS: Patients with SSc duration of <18 months were randomly assigned to the placebo group or to 1 of 3 CAT-192 treatment groups: 10 mg/kg, 5 mg/kg, 0.5 mg/kg. Infusions were given on day 0 and weeks 6, 12, and 18. The primary objective of this study was to evaluate the safety, tolerability, and pharmacokinetics of CAT-192. Secondary outcomes included the modified Rodnan skin thickness score (MRSS), the Scleroderma Health Assessment Questionnaire, assessment of organ-based disease, serum levels of soluble interleukin-2 receptor, collagen propeptides (N propeptide of type I [PINP] and type III collagen), and tissue levels of messenger RNA for procollagens I and III and for TGFbeta1 and TGFbeta2. RESULTS: Forty-five patients were enrolled. There was significant morbidity and mortality, including 1 death in the group receiving 0.5 mg/kg of CAT-192 and 3 deaths in the group receiving 5 mg/kg of CAT-192. There were more adverse events and more serious adverse events in patients receiving CAT-192 than in those receiving placebo, although these events were not more frequent in the high-dose treatment group. The MRSS improved in all groups during the study, but there was no evidence of a treatment effect for CAT-192. Improvement in the MRSS correlated with the disease duration (r = -0.54, P = 0.0008). Changes in the PINP level from baseline correlated with changes in the MRSS (r = 0.37, P = 0.027). CONCLUSION: We report the first evaluation of a systemically administered and repeatedly dosed anti-TGFbeta1 drug. In this pilot study, CAT-192, in doses up to 10 mg/kg, showed no evidence of efficacy. The utility of clinical and biochemical outcome measures and the feasibility of multicenter trials of early dcSSc were confirmed.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Immunosuppressive Agents/immunology , Scleroderma, Diffuse/therapy , Transforming Growth Factor beta1/immunology , Adult , Antibodies, Monoclonal/pharmacokinetics , Biomarkers/metabolism , Collagen Type I/genetics , Collagen Type I/metabolism , Collagen Type III/genetics , Collagen Type III/metabolism , Dose-Response Relationship, Drug , Female , Health Status , Humans , Infusions, Intravenous , International Cooperation , Male , Middle Aged , RNA, Messenger/metabolism , Recombinant Proteins , Scleroderma, Diffuse/pathology , Scleroderma, Diffuse/physiopathology , Skin/drug effects , Skin/pathology , Surveys and Questionnaires , Transforming Growth Factor beta1/genetics , Transforming Growth Factor beta1/metabolism , Transforming Growth Factor beta2/genetics , Transforming Growth Factor beta2/metabolism , Treatment Outcome
6.
Arthritis Rheum ; 55(4): 603-9, 2006 Aug 15.
Article in English | MEDLINE | ID: mdl-16874783

ABSTRACT

OBJECTIVE: To examine the validity of a durometer to objectively measure skin hardness in systemic sclerosis (SSc), and to compare digital durometry with the modified Rodnan skin score (MRSS) and ultrasonography. METHODS: Patients with SSc and healthy controls underwent durometry measurements in 3 assessments: a Latin square experiment to establish durometry's intra- and interobserver reliability compared with skin scoring (5 SSc, 1 control); a longitudinal cohort to assess sensitivity to change in skin hardness (13 SSc, 5 controls); and an ultrasound cohort to evaluate correlation between durometry, ultrasound-measured skin thickness, and clinical skin scoring (30 SSc, 12 controls). RESULTS: Intraobserver reproducibility was higher for durometry than for clinical skin scoring (intraclass correlation coefficient [ICC] 0.97 versus 0.85), whereas interobserver reproducibility was similar (0.75 versus 0.73). Interobserver reproducibility of durometry was good for all body areas (ICC 0.61-0.85), but for skin scoring it was moderate in the legs (0.51) and poor in the abdomen (0.08), feet (0.09), and fingers (0.27). Durometry scores correlated with clinical skin scores (Latin square: r = 0.44, P = 0.03; longitudinal cohort: r = 0.81, P < 0.001) and ultrasound-measured skin thickness (hands: r = 0.58, forearms: r = 0.63, upper arms: r = 0.40; P < or = 0.001 for all). Uninvolved skin in patients with SSc was harder than skin from controls (mean +/- SD 23 +/- 7 durometer units [DU] versus 19 +/- 6 DU; P < 0.0001). Finally, there was a strong correlation between change in MRSS and change in durometry score (r = 0.77, P = 0.002). CONCLUSION: Durometer-measured skin hardness correlates well with MRSS and ultrasound-measured skin thickness, provides greater reliability than MRSS, and is sensitive to changes in skin hardness over time. Durometry should be considered for use in clinical therapeutic SSc trials.


Subject(s)
Scleroderma, Systemic/physiopathology , Skin Diseases/diagnosis , Skin Diseases/physiopathology , Skin/pathology , Arm , Cohort Studies , Fingers , Hand , Humans , Observer Variation , Reference Values , Sensitivity and Specificity , Skin Diseases/etiology , Skinfold Thickness
7.
Matrix Biol ; 25(4): 213-22, 2006 May.
Article in English | MEDLINE | ID: mdl-16520029

ABSTRACT

Cartilage oligomeric matrix protein (COMP) is an extracellular glycoprotein that belongs to the thrombospondin gene family. It is found predominantly in cartilage, tendon, ligament, and bone. Mutations in the COMP gene have been linked to the development of pseudoachondroplasia and multiple epiphysial dysplasia. COMP influences the organization of collagen fibrils by interacting with collagens I, II and IX. Gene expression profiling of cultured skin fibroblasts suggested that COMP mRNA levels were elevated in scleroderma. We therefore examined COMP expression in SSc and normal skin biopsies. Immunohistochemistry confirmed that COMP protein accumulates in SSc but not normal skin, with SSc skin showing striking deposition in the papillary and deeper dermis. Significant staining was also seen in non-lesional skin from patients. Due to its involvement in the development of fibrosis, TGFbeta was examined for a possible role in regulating COMP expression. Cultured SSc fibroblasts demonstrated greater staining for COMP compared to normal controls prior to stimulation, and TGFbeta-1 induced a large increase in mRNA and protein. Murine fibroblasts engineered to overexpress human COMP demonstrated increased levels of fibronectin and collagen in the extracellular matrix. Taken together, these data demonstrate that COMP is overexpressed in SSc skin and cultured fibroblasts possibly due to autocrine TGFbeta stimulation, and COMP overexpression is sufficient to stimulate excess matrix deposition. By interactions with other matrix proteins and cells, COMP may play a role in pathogenic matrix deposition.


Subject(s)
Extracellular Matrix Proteins/metabolism , Fibroblasts/metabolism , Gene Expression , Glycoproteins/metabolism , Scleroderma, Systemic/pathology , Skin/pathology , Animals , Cartilage Oligomeric Matrix Protein , Cells, Cultured , Collagen/metabolism , Extracellular Matrix Proteins/genetics , Fibronectins/metabolism , Glycoproteins/genetics , Humans , Matrilin Proteins , Mice , RNA, Messenger , Skin/metabolism , Transforming Growth Factor beta/metabolism
8.
Arthritis Rheum ; 52(6): 1812-23, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15934076

ABSTRACT

OBJECTIVE: Mutations in fibrillin 1, a key component of extracellular microfibrils, are associated with connective tissue disorders such as Marfan's syndrome or skin fibrosis in the tight skin mouse model of scleroderma. Previous studies have suggested that fibrillin 1 mediates skin fibrosis via its interface with associated microfibrillar proteins and type I collagen; in particular, microfibril-associated glycoprotein 2 (MAGP-2), an extracellular matrix protein that binds to fibrillins and the alphavbeta3 integrin, is increased in TSK mouse and human scleroderma skin. Because the function of MAGP-2 in the biologic processes of the matrix remains unknown, this study investigated whether MAGP-2 regulates type I collagen. METHODS: Fibroblast cultures conditionally overexpressing MAGP-2 were developed. Cells were analyzed by Western blotting, Northern blotting, pulse-chase analysis, and immunofluorescence to assess the effect of MAGP-2 on type I collagen. RESULTS: Cells overexpressing MAGP-2 formed increased MAGP-2 matrix and showed a 3-fold increase in intracellular type I procollagen. This increase was associated with increased levels of type I collagen in the medium and matrix. Increased type I collagen colocalized with the MAGP-2 matrix. MAGP-2 overexpression had no effect on type I procollagen messenger RNA, but markedly increased the half-life of type I procollagen. MAGP-2 induced type I collagen even under conditions in which no MAGP-2 matrix was detectable, and did not require the presence of the RGD motif of MAGP-2 in its integrin-binding site. CONCLUSION: This study shows that MAGP-2 stabilizes type I procollagen, identifying an important function of MAGP-2 in extracellular matrix homeostasis. It also suggests that MAGP-2 might mediate skin fibrosis in TSK mice and in patients with scleroderma.


Subject(s)
Collagen Type I/biosynthesis , Contractile Proteins/metabolism , Extracellular Matrix Proteins/metabolism , Scleroderma, Systemic/physiopathology , Skin/pathology , Animals , Cell Line , Fibroblasts , Fibrosis , Mice , Microfibrils/pathology , RNA Splicing Factors , Scleroderma, Systemic/metabolism
9.
J Rheumatol ; 32(5): 832-40, 2005 May.
Article in English | MEDLINE | ID: mdl-15868618

ABSTRACT

OBJECTIVE: This study compares the responsiveness to change of the Medical Outcomes Study Short Form Health Survey (SF-36), a measure of health related quality of life (HRQOL), and the Health Assessment Questionnaire Disability Index (HAQ-DI), a function instrument, in a randomized clinical trial for treatment of systemic sclerosis (SSc). METHODS: A phase 2/3, multicenter, prospective, placebo controlled trial was conducted to evaluate human recombinant relaxin treatment in patients with diffuse SSc over 24 weeks. At baseline, subjects had stable, moderately severe, diffuse SSc of disease duration < or = 5 years, modified Rodnan skin score > or = 20, serum creatinine < 2.0 mg/dl, percentage forced vital capacity (% FVC) predicted > or = 50%, and % DLCO predicted > or = 40% and were not receiving concomitant disease modifying therapies. Internal consistency reliability of multi-item scales was estimated using Cronbach's alpha. Responsiveness to change of the SF-36 and HAQ-DI was computed between Weeks 0 and 24. Subjects were classified as unchanged or having a meaningful change in 4 different external measures: Change in (1) skin score > or = 30%; (2) % FVC predicted of > or = 15%; (3) self-reported patient global assessment by visual analog scale (VAS) > or = 20%; and (4) physician global assessment by VAS of > or = 20%. Responsiveness indices were computed and Cohen's effect size criteria were used to assess the magnitude of change. RESULTS: A total of 239 patients participated in this trial, with 196 completing the 24 week trial. Cronbach's alpha for the SF-36 scales ranged from 0.76 to 0.93 and for the HAQ-DI ranged from 0.69 to 0.91 (good to excellent). The SF-36 had a larger magnitude of responsiveness in overall disease (patient and physician global assessment) compared to the HAQ-DI, while the HAQ-DI had a larger magnitude of responsiveness in clinical measures (i.e., change in skin score and % FVC predicted) than the SF-36. CONCLUSION: These data support inclusion of both the SF-36 and HAQ-DI as outcome measures in future clinical trials of diffuse SSc.


Subject(s)
Disability Evaluation , Health Status Indicators , Relaxin/administration & dosage , Scleroderma, Systemic/drug therapy , Scleroderma, Systemic/physiopathology , Adult , Aged , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Prospective Studies , Quality of Life , Reproducibility of Results , Scleroderma, Systemic/diagnosis , Skin , Surveys and Questionnaires/standards
10.
J Invest Dermatol ; 124(2): 298-303, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15675946

ABSTRACT

Recent studies suggest that, in addition to activation and hypersecretion of matrix components, fibroblasts from patients with systemic sclerosis (SSc) are relatively resistant to apoptosis. Transforming growth factor-beta (TGF)-beta is strongly implicated in the pathogenesis of SSc and we and others have shown that TGF-beta can activate Akt, a kinase with potent anti-apoptotic effects. To determine whether Akt was activated in SSc, we quantified phospho-Akt expression in skin fibroblasts in vitro by western blot analysis and a functional kinase assay. In addition, the relative proportion of fibroblasts containing activated Akt in was quantified by immunohistochemistry on skin sections insitu. Analysis of Akt phosphorylation of skin fibroblasts in vitro suggested increased phosphorylation of Akt, and evaluation of skin sections by immunohistochemistry revealed significantly higher percentages of fibroblasts that stained for phospho-Akt compared with controls (78% +/- 14.0% vs 13% +/- 9%, p < 0.001). In addition, co-incident staining of phospho-Akt and alpha-smooth muscle actin was observed in some fibroblasts. These findings indicate that Akt is activated insitu in skin fibroblasts from patients with SSc. Akt activation may contribute to resistance to apoptosis, selection of disease-inducing fibroblasts, and, possibly, myofibroblasts.


Subject(s)
Fibroblasts/enzymology , Fibroblasts/pathology , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins/metabolism , Scleroderma, Systemic/metabolism , Scleroderma, Systemic/pathology , Apoptosis/physiology , Cells, Cultured , Female , Humans , Male , Middle Aged , Proto-Oncogene Proteins c-akt , Signal Transduction/physiology , Skin/enzymology , Skin/pathology , Transforming Growth Factor beta/metabolism
11.
J Invest Dermatol ; 123(6): 1063-9, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15610515

ABSTRACT

The Tight skin (Tsk) mouse is an important model of skin fibrosis that occurs in systemic sclerosis. These mice develop skin tethering and thickening associated with expression of a mutant fibrillin-1 gene. We show that Tsk fibrillin-1 leads to marked alterations in elastic fibers of the hypodermis of Tsk animals. In Tsk mice, a prominent elastic fiber layer found normally at the interface between hypodermal muscle and connective tissue was absent from an early age. The lack of elastic fibers at the hypodermal muscle-connective tissue (M-CT) interface was associated with a loss of staining for fibulin-5 in the same region. These mice also formed disorganized elastic fibers throughout hypodermal connective tissue as they aged. The increased elastic fibers in Tsk hypodermal connective tissue was associated with increased fibrillin-1 and fibulin-2 matrices. These results suggest that Tsk fibrillin-1 causes skin tethering by altering matrix protein composition in Tsk hypodermal connective tissues. The closely parallel alterations in elastogenesis associated with increased fibulin-2 in hypodermal connective tissues and decreased fibulin-5 at the hypodermal M-CT interface suggest that these proteins mediate the effect of Tsk-fibrillin-1 on elastogenesis.


Subject(s)
Calcium-Binding Proteins/genetics , Extracellular Matrix Proteins/genetics , Scleroderma, Systemic/pathology , Scleroderma, Systemic/physiopathology , Subcutaneous Tissue/pathology , Subcutaneous Tissue/physiopathology , Animals , Calcium-Binding Proteins/metabolism , Elasticity , Extracellular Matrix/metabolism , Extracellular Matrix/pathology , Extracellular Matrix Proteins/metabolism , Fibrillin-1 , Fibrillins , Fibroblasts/metabolism , Fibroblasts/pathology , Mice , Mice, Inbred Strains , Mice, Mutant Strains , Microfilament Proteins/metabolism , RNA, Messenger/analysis , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Subcutaneous Tissue/metabolism
12.
Arthritis Rheum ; 50(3): 915-26, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15022335

ABSTRACT

OBJECTIVE: Skin fibrosis in the TSK mouse, a model of skin fibrosis seen in systemic sclerosis (SSc), is caused by a large in-frame duplication in the Fbn1 gene, tsk-Fbn1. We investigated whether tsk-Fbn1 might cause dermal fibrosis by affecting Fbn1 and associated extracellular matrices. We also studied whether deposition of microfibril-associated glycoprotein 2 (MAGP-2), a protein that is associated with fibrillin 1, was altered in the skin of patients with SSc. METHODS: An in vitro model of the TSK mouse was created by conditionally expressing tsk-Fbn1 in mouse embryonic fibroblasts (MEFs). Cell cultures were examined by immunofluorescence and Western and Northern blotting to determine the effect of tsk-Fbn1 on the structure, expression, and deposition of fibrillin 1 (Fbn-1), type I collagen, and MAGP-2. The skin of TSK mice and SSc patients was analyzed by immunohistochemistry for MAGP-2 expression. RESULTS: Expression of tsk-Fbn1 in cultured MEF cells altered the morphology of Fbn-1 fibers and increased the deposition of type I collagen into the extracellular matrix (ECM) without concomitantly changing messenger RNA expression, secretion, or processing of type I procollagen. Moreover, MEF cells expressing tsk-Fbn1 showed increased MAGP-2 matrix. MAGP-2 was increased in the dermis of TSK mice. Fibrotic SSc skin also showed higher levels of MAGP-2 in the dermis than nonfibrotic SSc skin and normal skin. CONCLUSION: Tsk-Fbn1 altered ECM organization and caused fibrosis by affecting the deposition of MAGP-2 or other Fbn-1-associated proteins. Alterations in microfibril structure or deposition might contribute to fibrosis in SSc.


Subject(s)
Collagen Type I/metabolism , Contractile Proteins/metabolism , Extracellular Matrix Proteins , Extracellular Matrix/metabolism , Microfilament Proteins/genetics , Microfilament Proteins/metabolism , Mutation , Scleroderma, Systemic/metabolism , Animals , Collagen Type I/genetics , Fibrillin-1 , Fibrillins , Fibroblasts/metabolism , Fibrosis , Mice , Mice, Mutant Strains , Microfibrils/metabolism , Microfibrils/pathology , Microfilament Proteins/chemistry , Molecular Structure , RNA Splicing Factors , RNA, Messenger/metabolism , Scleroderma, Systemic/pathology , Skin/metabolism , Skin/pathology
13.
Cleve Clin J Med ; 70(11): 954, 956, 958 passim, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14650470

ABSTRACT

Many effective treatments for scleroderma have emerged in recent years, including bosentan, an endothelin receptor antagonist, and epoprostenol, a prostacyclin, both of which target vasoconstriction. Cyclophosphamide may soon be proven effective against interstitial lung disease.


Subject(s)
Scleroderma, Systemic/therapy , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Antihypertensive Agents/therapeutic use , Bosentan , Humans , Pulmonary Fibrosis/etiology , Scleroderma, Systemic/complications , Scleroderma, Systemic/physiopathology , Sulfonamides/therapeutic use
14.
Rheum Dis Clin North Am ; 29(2): 351-69, 2003 May.
Article in English | MEDLINE | ID: mdl-12841299

ABSTRACT

The pathogenesis of fibrosis in scleroderma involves a complex set of interactions between the fibroblast and its surroundings. Multiple fibrotic pathways are activated for reasons that are not completely clear, but involve immune activation, microvascular damage, and fibroblast transformation into the myofibroblast. Differential proliferation and apoptosis preserve the myofibroblast phenotype rather that leading to a selective depletion of activated fibroblasts after an acute injury has healed. Disproportionate fibroblast activity could result from a combination of possible cellular and matrix defects that include fibrillin protein abnormalities, autoantibody formation, type II immune response, excessive endothelial reaction to injury, and excessive fibroblast response to TGF-beta. Development of therapies that are targeted to correcting these abnormalities will eventually lead to effective treatment for the fibrotic complications of scleroderma.


Subject(s)
Fibrosis/etiology , Scleroderma, Systemic/complications , Fibroblasts/pathology , Fibroblasts/physiology , Fibrosis/pathology , Fibrosis/physiopathology , Humans , Scleroderma, Systemic/pathology , Scleroderma, Systemic/physiopathology
16.
Curr Opin Rheumatol ; 14(6): 717-22, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12410097

ABSTRACT

The hallmark of scleroderma is cutaneous and visceral fibrosis characterized and by increased biosynthesis of multiple matrix proteins by interstitial fibroblasts. Studies over recent years have delineated pathways involved in promoting matrix synthesis and elucidated the molecular pathways of regulation. Central to the regulation of fibrosis are extracellular mediators, called cytokines, which are elaborated by a variety of cells, including those in the immune system, vascular cells, and fibroblasts themselves. The concept that inhibiting or promoting the action of these naturally occurring profibrotic or antifibrotic molecules, respectively, is a rational therapeutic approach to treating scleroderma and other fibrotic diseases finds support in animal studies and anticytokine therapy conducted in relation to rheumatoid arthritis and other disorders. This review looks at cytokines known or thought to play a role in scleroderma and/or other fibrotic states and at potential therapy directed at these mediators. Potential targets for therapy include transforming growth factor beta (TGF-beta), connective tissue growth factor (CTGF), IL-4, IL-13, MCP-1, and endothelin, among others.


Subject(s)
Cytokines/immunology , Immunotherapy , Scleroderma, Systemic/therapy , Animals , Disease Models, Animal , Humans , Pulmonary Fibrosis/etiology , Pulmonary Fibrosis/immunology , Pulmonary Fibrosis/therapy , Scleroderma, Systemic/complications , Scleroderma, Systemic/immunology
17.
Arthritis Rheum ; 46(11): 3000-9, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12428243

ABSTRACT

OBJECTIVE: Fibrillin, an extracellular matrix protein implicated in dermal fibrosis, is increased in the reticular dermis of systemic sclerosis (SSc) skin. We undertook this study to investigate the hypothesis that transforming growth factor beta (TGFbeta) or other cytokines regulate fibrillin matrix formation by normal and SSc fibroblasts. We further investigated the mechanism of TGFbeta-induced fibrillin fibrillogenesis and its relationship to myofibroblasts. METHODS: Fibrillin and fibronectin matrix deposition and alpha-smooth muscle actin expression by fibroblast cultures from normal and SSc skin treated with TGFbeta or other cytokines were analyzed by immunofluorescence. Supernatant and extracellular matrix from normal and SSc fibroblasts treated with or without TGFbeta were evaluated by Western blot and Northern blot for fibrillin protein and messenger RNA (mRNA) expression, respectively. RESULTS: Immunofluorescence demonstrated increased fibrillin matrix formation by normal and scleroderma fibroblasts after TGFbeta treatment. Other cytokines, including tumor necrosis factor alpha, interleukin-1beta (IL-1beta), IL-4, granulocyte-macrophage colony-stimulating factor, and platelet-derived growth factor, did not affect fibrillin fibrillogenesis. Fibrillin matrix formed in proximity to myofibroblasts and independently of up-regulation of fibronectin matrix or cell number. Western blot analysis of extracellular matrix confirmed increased fibrillin after TGFbeta stimulation of normal or scleroderma fibroblasts. However, TGFbeta did not alter the expression of either soluble fibrillin protein or fibrillin mRNA. CONCLUSION: Our data show that TGFbeta induces fibrillin protein incorporation into the extracellular matrix without affecting fibrillin gene expression or protein synthesis, suggesting that fibrillin matrix assembly is regulated extracellularly. TGFbeta might increase fibrillin matrix by activating myofibroblasts. Such TGFbeta-mediated effects could account for the increased fibrillin matrix observed in SSc skin.


Subject(s)
Fibroblasts/metabolism , Microfilament Proteins/biosynthesis , Scleroderma, Systemic/metabolism , Transforming Growth Factor beta/physiology , Cells, Cultured , Cytokines/physiology , Fibrillin-1 , Fibrillins , Fluorescent Antibody Technique , Humans , RNA, Messenger/analysis
18.
Arthritis Rheum ; 46(9): 2410-20, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12355489

ABSTRACT

OBJECTIVE: To document disease activity and functional status in patients with scleroderma (systemic sclerosis [SSc]) and Raynaud's phenomenon (RP) and to determine the sensitivity to change, reliability, ease of use, and validity of various outcome measures in these patients. METHODS: Patients with SSc and moderate-to-severe RP participating in a multicenter RP treatment trial completed daily diaries documenting the frequency and duration of RP attacks and recorded a daily Raynaud's Condition Score (RCS). Mean scores for the 2-week periods prior to baseline (week 0), end of trial (week 6), and posttrial followup (week 12) were calculated. At weeks 0, 6, and 12, physicians completed 3 global assessment scales and performed clinical assessments of digital ulcers and infarcts; patients completed the Health Assessment Questionnaire (HAQ), the Arthritis Impact Measurement Scales 2 (AIMS2) mood and tension subscales, 5 specific SSc/RP-related visual analog scales (VAS), and 3 other VAS global assessments. We used these measures to document baseline disease activity and to assess their construct validity, sensitivity to change, and reliability in trial data. RESULTS: Two hundred eighty-one patients (248 women, 33 men; mean age 50.4 years [range 18-82 years]) from 14 centers participated. Forty-eight percent had limited cutaneous SSc; 52% had diffuse cutaneous SSc. Fifty-nine patients (21%) had digital ulcers at baseline. Patients had 3.89 +/- 2.33 (mean +/- SD) daily RP attacks (range 0.8-14.6), with a duration of 82.1 +/- 91.6 minutes/attack. RCS for RP activity (possible range 0-10) was 4.30 +/- 1.92. HAQ scores (0-3 scale) indicated substantial disability at baseline (total disability 0.86, pain 1.19), especially among the subscales pertaining to hand function (grip, eating, dressing). AIMS2 mood and tension scores were fairly high, as were many of the VAS scores. Patients with digital ulcers had worse RCS, pain, HAQ disability (overall, grip, eating, and dressing), physician's global assessment, and tension, but no significant difference in the frequency of RP, duration of RP, patient's global assessment, or mood, compared with patients without digital ulcers. VAS scores for digital ulcers as rated by the patients were not consistent with the physician's ratings. Factor analysis of the 18 measures showed strong associations among variables in 4 distinct domains: disease activity, RP measures, digital ulcer measures, and mood/tension. Reliability of the RCS, HAQ pain and disability scales, and AIMS2 mood and tension subscales was high. The RP measures demonstrated good sensitivity to change (effect sizes 0.33-0.76). CONCLUSION: Our findings demonstrate that the significant activity, disability, pain, and psychological impact of RP and digital ulcers in SSc can be measured by a small set of valid and reliable outcome measures. These outcome measures provide information beyond the quantitative metrics of RP attacks. We propose a core set of measures for use in clinical trials of RP in SSc patients that includes the RCS, patient and physician VAS ratings of RP activity, a digital ulcer/infarct measure, measures of disability and pain (HAQ), and measures of psychological function (AIMS2).


Subject(s)
Raynaud Disease/physiopathology , Scleroderma, Localized/physiopathology , Scleroderma, Systemic/physiopathology , Affect , Aged , Aged, 80 and over , Disabled Persons , Extremities , Female , Humans , Male , Medical Records , Middle Aged , Multicenter Studies as Topic , Randomized Controlled Trials as Topic , Raynaud Disease/complications , Raynaud Disease/psychology , Scleroderma, Localized/psychology , Scleroderma, Systemic/psychology , Severity of Illness Index , Sickness Impact Profile , Surveys and Questionnaires , Ulcer/etiology
19.
Curr Rheumatol Rep ; 4(2): 129-35, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11890878

ABSTRACT

Tissue fibrosis is the result of a complex series of events focusing on regulation of fibroblast proliferation, synthesis of extracellular matrix, and apoptosis. Transforming growth factor-beta is important for the stimulation of the fibrotic response by promoting the production of extracellular matrix proteins, by promoting the differentiation of the myofibroblast cell morphology, and by protecting these cells against apoptotic stimuli. Other cytokines such as interleukin-1 may have stimulatory and counter-regulatory effects on fibrosis. The effects of these signaling molecules depend on cellular environment and are organ specific. Furthermore, intercellular interactions and cell-matrix interactions can stimulate or inhibit the apoptotic pathway. Through selective inhibition of apoptosis in myofibroblasts, fibrosis can become dysregulated and lead to diseases such as systemic sclerosis.


Subject(s)
Apoptosis , Scleroderma, Systemic/etiology , Animals , Fibroblasts , Fibrosis , Humans , Transforming Growth Factor beta/physiology
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