Effect of bosentan on skin fibrosis in patients with systemic sclerosis: a prospective, open-label, non-comparative trial

Systemic pharmacological treatment of digital ulcers in systemic sclerosis: a systematic literature review

OBJECTIVE

To evaluate the evidence concerning systemic pharmacological treatments for SSc digital ulcers (DUs) to inform the development of evidence-based treatment guidelines.

METHODS

A systematic literature review of seven databases was performed to identify all original research studies of adult patients with SSc DUs. Randomized controlled trials (RCTs) and prospective longitudinal observational studies (OBSs) were eligible for inclusion. Data were extracted, applying the patient, intervention, comparison, outcome framework, and risk of bias (RoB) was assessed. Due to study heterogeneity, narrative summaries were used to present data.

RESULTS

Forty-seven studies that evaluated the treatment efficacy or safety of pharmacological therapies were identified among 4250 references. Data from 18 RCTs of 1927 patients and 29 OBSs of 661 patients, at various RoB (total 2588 patients) showed that i.v. iloprost, phosphodiesterase-5 inhibitors and atorvastatin are effective for the treatment of active DUs. Bosentan reduced the rate of future DUs in two RCTs (moderate RoB) and eight OBSs at low to high RoB. Two small studies (moderate RoB) indicate that Janus kinase inhibitors may be effective for the treatment of active DUs, otherwise there are no data to support the use of immunosuppression or anti-platelet agents in the management of DUs.

CONCLUSION

There are several systemic treatments, across four medication classes, that are effective therapies for the management of SSc DUs. However, a lack of robust data means it is not possible to define the optimal treatment regimen for SSc DUs. The relatively low quality of evidence available has highlighted further areas of research need.

The Pathogenesis of Systemic Sclerosis: The Origin of Fibrosis and Interlink with Vasculopathy and Autoimmunity

Systemic sclerosis (SSc) is an autoimmune disease associated with increased mortality and poor morbidity, impairing the quality of life in patients. Whilst we know that SSc affects multiple organs via vasculopathy, inflammation, and fibrosis, its exact pathophysiology remains elusive. Microvascular injury and vasculopathy are the initial pathological features of the disease. Clinically, the vasculopathy in SSc is manifested as Raynaud's phenomenon (reversible vasospasm in reaction to the cold or emotional stress) and digital ulcers due to ischemic injury. There are several reports that medications for vasculopathy, such as bosentan and soluble guanylate cyclase (sGC) modulators, improve not only vasculopathy but also dermal fibrosis, suggesting that vasculopathy is important in SSc. Although vasculopathy is an important initial step of the pathogenesis for SSc, it is still unclear how vasculopathy is related to inflammation and fibrosis. In this review, we focused on the clinical evidence for vasculopathy, the major cellular players for the pathogenesis, including pericytes, adipocytes, endothelial cells (ECs), and myofibroblasts, and their signaling pathway to elucidate the relationship among vasculopathy, inflammation, and fibrosis in SSc.

Emerging Therapeutics in the Management of Connective Tissue Disease. Part II. Dermatomyositis and Scleroderma

The management of connective tissue diseases is dramatically evolving with the advent of biologics and novel oral systemic therapeutics. Despite involvement in the care of these complex patients, there is a knowledge gap in the field of dermatology regarding these emerging agents. The second article in this continuing medical education series discusses new and emerging therapeutics for dermatomyositis and scleroderma that target cells, intracellular signaling pathways, and cytokines.

Ultrasound and elastography in the assessment of skin involvement in systemic sclerosis: A systematic literature review focusing on validation and standardization - WSF Skin Ultrasound Group

OBJECTIVE

To summarize the published evidence in the literature on the role of ultrasound and elastography to assess skin involvement in systemic sclerosis (SSc).

METHODS

A systematic literature review (SLR) was performed within the "Skin Ultrasound Working Group" of the World Scleroderma Foundation, according to the Cochrane Handbook. A search was conducted in Pubmed, Cochrane Library and Embase databases from 1/1/1979 to 31/5/2021, using the participants, intervention, comparator and outcomes (PICO) framework. Only full-text articles involving adults, reported in any language, assessing ultrasound to quantify skin pathology in SSc patients. Two reviewers performed the assessment of risk of bias, data extraction and synthesis, independently.

RESULTS

Forty-six studies out of 3248 references evaluating skin ultrasound and elastography domains were included. B-mode ultrasound was used in 30 studies (65.2%), elastography in nine (19.6%), and both methods in seven (15.2%). The ultrasound outcome measure domains reported were thickness (57.8%) and echogenicity (17.2%); the elastography domain was stiffness (25%). Methods used for image acquisition and analysis were remarkably heterogeneous and frequently under-reported, precluding data synthesis across studies. The same applies to contextual factors and feasibility. Our data syntheses indicated evidence of good reliability and convergent validity for ultrasound thickness evaluation against mRSS and skin histological findings. Stiffness and echogenicity have limited evidence for validity against histological findings. Evidence for sensitivity to change, test-retest reliability, clinical trial discrimination or thresholds of meaning is limited or absent for reported ultrasound domains.

CONCLUSION

Ultrasound is a valid and reliable tool for skin thickness measurement in SSc but there are significant knowledge gaps regarding skin echogenicity assessment by ultrasound and skin stiffness evaluation by elastography in terms of feasibility, validity and discrimination. Standardization of image acquisition and analysis is needed to foster progress.

Atractylenolide III inhibits epithelial‑mesenchymal transition in small intestine epithelial cells by activating the AMPK signaling pathway

Compared with the available drugs for the treatment of fibrosis in other organs, the development of intestinal anti-fibrosis drugs is limited. Therefore, it is of practical significance to examine novel drugs to delay or block the development of intestinal fibrosis. The present study aimed to investigate the effect of atractylenolide III (ATL-III) on intestinal fibrosis. An MTT assay was used to detect the effect of ATL-III on the activity of IEC-6 cells. The migration and invasion of fibrotic cells stimulated with TGF-β were determined via wound healing and Transwell assays. An immunofluorescence assay and western blotting were conducted to assess the expression levels of protein associated with epithelial-mesenchymal transition (EMT). The role of the AMP-activated protein kinase (AMPK) pathway was verified using compound C (an AMPK inhibitor) treatment. The results of the present study indicated that ATL-III had no effect on the cells at a dose of 1–20 µmol/l. Moreover, ATL-III can inhibit the invasion and migration of cells induced by TGF-β1, as well as block the EMT process. It was found that ATL-III could also activate the AMPK pathway. Furthermore, compound C reduced the inhibitory effect of ATL-III on stimulated cells, which indicated that the AMPK pathway plays a role in the inhibition process. In conclusion, ATL-III may inhibit the EMT of IEC-6 cells stimulated with TGF-β1 by activating the AMPK signaling pathway.

Current Topics of the Mechanism of Intestinal Fibrosis in Crohn’s Disease

Intestinal fibrosis is one of the most common intestinal complications observed in inflammatory bowel disease, especially Crohn’s disease (CD). Intestinal fibrosis in CD is associated with chronic inflammation resulting from immunologic abnormalities and occurs as a form of tissue repair during the anti-inflammatory process. Various types of immune cells and mesenchymal cells, including myofibroblasts, are intricately involved in causing intestinal fibrosis. It is often difficult to treat intestinal fibrosis as intestinal stricture may develop despite treatment aimed at controlling inflammation. Detailed analysis of the pathogenesis of intestinal fibrosis is critical towards advancing the development of future therapeutic applications.

Epidemiology of fibrostenosing inflammatory bowel disease

Fibrostenosis occurs in both Crohn's disease (CD) and ulcerative colitis (UC). Up to 21% of patients with CD present with strictures at diagnosis, while the rate of stenosis varies from 1% to 11% in UC. Despite the increasing use of immunomodulators and biologics in treatment, there has been no decrease in the rate of progression from inflammatory to complicated disease phenotypes (either stricturing or penetrating). The presence of stenosis is an independent risk factor for surgery in patients with CD, who are at a risk of postoperative recurrence at a rate of up to 55% at 10 years after surgery. Patients with inflammatory bowel disease (IBD) strictures are at risk of malignant transformation. Thus, surveillance colonoscopy should be offered to this group of patients. Several risk factors for the development of stricture have been identified. In CD, patients aged less than 40-years old, with perianal disease at diagnosis, who need steroids at the first flare up or have ileal disease are at the risk of developing strictures; while in UC, patients with extensive colitis and long-standing disease are at risk. Recently, microbiota signatures have also been identified as markers for stricture development. The presence of Ruminococcus spp. is associated with the development of stricture in pediatric patients with CD. In this review, we highlight the epidemiology, risk factors and natural history of fibrostenosing IBD.

Drugs in phase I and phase II clinical trials for systemic sclerosis

Introduction: Systemic sclerosis (SSc) is an autoimmune connective tissue disease that is characterized by excessive collagen deposition, vascular dysfunction, and fibrosis of cutaneous and visceral organs. Current therapeutic options are limited and provide only modest benefit.Areas covered: This review summarizes investigational agents in recent Phase I and II clinical trials evaluated for the treatment of SSc with a focus on skin in patients with early diffuse disease and interstitial lung disease. We performed a search on Pubmed and https://clinicaltrials.gov with keywords systemic sclerosis, Phase I clinical trial, and Phase II clinical trial to identify relevant studies from 2015 to 2019.Expert opinion: Therapeutic interventions in SSc should be guided by the level of disease activity and the degree of organ involvement. While most novel agents have failed to meet the primary endpoints of reducing skin thickening as measured by the modified Rodnan skin score, some have shown promise in improving the Composite Response Index for Clinical Trials in Early Diffuse Cutaneous Systemic Sclerosis (CRISS), reducing lung function decline, or improving patient-reported outcomes. However, most of the current evidence is based on small or open-label clinical trials. Well-designed, large, randomized, Phase III clinical trials are necessary to define the roles of investigational agents in treating SSc.

A prospective, open-label, non-comparative study of ambrisentan with anti-fibrotic agent combination therapy in the treatment of diffuse systemic sclerosis

Background

Systemic Sclerosis is a multifactorial autoimmune rheumatic disease characterized by inflammation, fibrosis, immune dysregulation and vascular dysfunction.

Methods

An open label, prospective, non-comparative study evaluating ambrisentan with an antifibrotic agent in diffuse cutaneous systemic sclerosis (dcSSc). Recruited 15 consecutive patients with dcSSc who were already on a stable dose of an antifibrotic agent and if they met inclusion criteria they were initiated on ambrisentan 5 mg/day for 12 months. Primary outcome measure was the modified Rodnan skin score (mRSS) while secondary measures were the short form 36 (SF-36) questionnaire, the Medsger severity score and pulmonary function studies.

Results

Fifteen patients were recruited and ten patients completed all 12 months of the study. An intention to treat was used to analyze the data. There was statistical improvement of the mean mRSS and the perceived change in health component of the SF-36. The Medsger severity score and pulmonary function studies remained unchanged over the course of the study.

Conclusion

Patients who tolerated the combination of an antifibrotic with ambrisentan had an improvement of their mRSS over the course of the study as well as an improvement of their perceived health.

Trial registration

Clinicaltrials.gov, NCT01093885; March 2010.

Identification of Endpoints for Development of Antifibrosis Drugs for Treatment of Crohn's Disease

BACKGROUND & AIMS

Intestinal fibrosis is a challenge to management of patients with Crohn's disease (CD); there is an urgent need to expedite development of antifibrosis drugs for this disease. The International Organization for the Study of Inflammatory Bowel Disease (IOIBD) aimed to identify a set of endpoints that can be used to determine efficacy of antifibrosis agents tested in clinical trials of patients with CD.

METHODS

We conducted a systematic review to identify clinical, radiologic, biochemical, endoscopic, and composite endpoints used in assessing activity of fibrostenosing CD and response to treatment, and determined their operational properties. A panel of IOIBD experts performed a consensus process to identify the best endpoints for inclusion in clinical trials, through a 2-round, Delphi-style online survey.

RESULTS

A total of 36 potentially relevant endpoints for intestinal fibrosis were selected and assessed. Forty-eight physicians with expertise in inflammatory bowel disease, from 5 regions (North America, Europe, Middle East, Asia/Pacific, and Latin America), participated in the Delphi consensus process. A core set of 13 endpoints (complete clinical response, long-term efficacy, sustained clinical benefit, treatment failure, radiological remission, normal quality of life, clinical remission without steroids, therapeutic failure, deep remission, complete absence of occlusive symptoms, symptom-free survival, bowel damage progression, and no disability) were rated as critical. Agreement was high among the experts.

CONCLUSIONS

Members of the IOIBD reached expert consensus on a set of endpoints that can be used to assess antifibrosis agents in trials of patients with CD. Studies are needed to clarify methods for measuring these outcomes and validate measurement instruments.

Diagnostic criteria, severity classification and guidelines of systemic sclerosis

Several effective drugs have been identified for the treatment of systemic sclerosis (SSc). However, in advanced cases, not only their effectiveness is reduced but they may be also harmful due to their side-effects. Therefore, early diagnosis and early treatment is most important for the treatment of SSc. We established diagnostic criteria for SSc in 2003 and early diagnostic criteria for SSc in 2011, for the purpose of developing evaluation of each organ in SSc. Moreover, in November 2013, the American College of Rheumatology and the European Rheumatology Association jointly developed new diagnostic criteria for increasing their sensitivity and specificity, so we revised our diagnostic criteria and severity classification of SSc. Furthermore, we have revised the clinical guideline based on the newest evidence. In particular, the clinical guideline was established by clinical questions based on evidence-based medicine according to the New Minds Clinical Practice Guideline Creation Manual (version 1.0). We aimed to make the guideline easy to use and reliable based on the newest evidence, and to present guidance as specific as possible for various clinical problems in treatment of SSc.

Systemic sclerosis: Current concepts of skin and systemic manifestations

Systemic sclerosis is an uncommon autoimmune connective tissue disease with multiorgan system involvement and significant associated morbidity and mortality. Cutaneous signs and clinical manifestations are of particular importance, as they may be recognized before systemic manifestations, allowing earlier risk stratification into the limited and diffuse cutaneous subtypes, as well as earlier initiation of treatment. Important cutaneous manifestations include Raynaud's phenomenon, digital ulcers, cutaneous sclerosis, calcinosis cutis, telangiectasias, pruritus, and dyspigmentation. Despite investigation of a wide variety of treatments, no FDA-approved pharmacologic therapies exist for systemic sclerosis, and data from high-quality studies are limited. In the following review, we will discuss skin-directed therapies. Although there is evidence to support specific treatments for Raynaud's phenomenon, digital ulcers, and cutaneous sclerosis, there are limited rigorous studies evaluating the treatment of other cutaneous signs and clinical manifestations. Additional randomized-controlled trials and large observational studies are necessary to develop future evidence-based treatment options.

Assessment of skin involvement in systemic sclerosis

Skin involvement in SSc is an important marker of disease activity, severity and prognosis, making the assessment of skin a key issue in SSc clinical research. We reviewed the published data assessing skin involvement in clinical trials and summarized the major conclusions important in SSc clinical research. A systematic literature review identified randomized controlled trials using skin outcomes in SSc. Analysis examined the validity of the different skin measures based on literature findings. Twenty-two randomized controlled trials were found. The average study duration was 10.2 (s.d. 4.5) months, mean (s.d.) sample size 32.4 (32.6) and 26.7 (27.8) in intervention and control arms, respectively. The 17-site modified Rodnan skin score is a fully validated primary outcome measure in diffuse cutaneous SSc. Skin histology seems to be an appropriate method for evaluation of skin thickness. These findings have important implications for clinical trial design targeting skin involvement in SSc.

The mighty fibroblast and its utility in scleroderma research

Fibroblasts are the effector cells of fibrosis characteristic of systemic sclerosis (SSc, scleroderma) and other fibrosing conditions. The excess production of extracellular matrix (ECM) proteins is the hallmark of fibrosis in different organs, such as skin and lung. Experiments designed to assess the pro-fibrotic capacity of factors, their signaling pathways, and potential inhibitors of their effects that are conducted in fibroblasts have paved the way for planning clinical trials in SSc. As such, fibroblasts have proven to be valuable tools in the search for effective anti-fibrotic therapies for fibrosis. Herein we highlight the characteristics of fibroblasts, their role in the etiology of fibrosis, utility in experimental assays, and contribution to drug development and clinical trials in SSc.

Systemic Sclerosis Dermal Fibroblasts Suppress Th1 Cytokine Production via Galectin-9 Overproduction due to Fli1 Deficiency

Dermal fibroblasts promote skin-localized transdifferentiation of regulatory T cells to T helper (Th) type 2-like cells in systemic sclerosis (SSc). However, the entire effect of SSc dermal fibroblasts on immune cells still remains unknown. Because galectin-9 induces Th2 cytokine-predominant immune imbalance by negatively regulating Th1/Th17 cells in inflammatory diseases, we investigated the contribution of galectin-9 to Th immune balance in SSc lesional skin. We used human clinical samples and Fli1^+/- mice because Fli1 deficiency induces SSc-like phenotypes in various cell types. Galectin-9 was overexpressed in SSc dermal fibroblasts in vivo and in vitro. Serum galectin-9 levels were significantly elevated in SSc patients and positively correlated with skin score. Galectin-9 was up-regulated by autocrine endothelin stimulation and Fli1 deficiency, and Fli1 occupied the LGALS9 promoter in dermal fibroblasts. Co-culture of splenic CD4⁺ T cells with Fli1^+/- dermal fibroblasts significantly increased IL-4-producing cell proportion, and this effect was cancelled in parallel with the increased interferon-γ production when Fli1^+/- dermal fibroblasts were transfected with Lgals9 small interfering RNA. Furthermore, Lgals9 small interfering RNA suppressed dermal collagen deposition by increasing interferon-γ production of skin-infiltrating CD4⁺ T cells in bleomycin-treated mice. These results suggest that SSc dermal fibroblasts suppress interferon-γ expression of skin-infiltrating CD4⁺ T cells through galectin-9 overproduction, promoting skin fibrosis development.

Mechanisms, Management, and Treatment of Fibrosis in Patients With Inflammatory Bowel Diseases

In the last 10 years, we have learned much about the pathogenesis, diagnosis, and management of intestinal fibrosis in patients with inflammatory bowel diseases. Just a decade ago, intestinal strictures were considered to be an inevitable consequence of long-term inflammation in patients who did not respond to anti-inflammatory therapies. Inflammatory bowel diseases-associated fibrosis was seen as an irreversible process that frequently led to intestinal obstructions requiring surgical intervention. This paradigm has changed rapidly, due to the antifibrotic approaches that may become available. We review the mechanisms and diagnosis of this serious complication of inflammatory bowel diseases, as well as factors that predict its progression and management strategies.

Longitudinal Evaluation of Central Corneal Thickness in Patients With Systemic Sclerosis

PURPOSE

To investigate the longitudinal change of central corneal thickness (CCT) in patients with systemic sclerosis (SSc) and to elucidate whether it contributes to misinterpretation of intraocular pressure (IOP) in this group of patients.

METHODS

Twenty patients with SSc and 20 sex- and age-matched controls were examined at 2 visits 5 years apart. Age, sex, race, subtype of SSc, disease duration, autoantibody profile, use of disease-modifying antirheumatic drugs (DMARDs), best-corrected visual acuity, spherical equivalent refraction, IOP, and CCT were recorded. IOP was assessed by applanation tonometry and CCT by ultrasonic pachymetry.

RESULTS

CCT decreased by 7.2 μm [95% confidence interval (CI), -2.1 to -12.2 μm] between the first and second measurements (P = 0.008) in patients with SSc and by 2.4 μm (P = 0.39, 95% CI, -8.0 to 3.3 μm) in the control group. Considering patients with SSc, CCT decreased by a mean of 11.6 μm [95% CI, -4.3 to -19.0 μm (P = 0.007)] among those taking DMARDs at the second visit and by 4.2 μm [95% CI, -3.0 to -11.5 μm (P = 0.2)] in patients not taking any DMARDs. There was no statistically significant change in IOP between the 2 visits for either the SSc group (P = 0.84) or the control group (P = 0.29). Mean change in CCT was not associated with either IOP at first visit or with change in IOP in SSc patients.

CONCLUSIONS

CCT decreased with time in SSc. However, the slight rates of thinning observed are unlikely to considerably influence applanation tonometry or clinical decision-making over the short to intermediate term.

Effect of endothelin-1 receptor antagonists on skin fibrosis in scleroderma patients from the EUSTAR database

Introduction

The aim of the study was to evaluate the effect of endothelin-1 receptor antagonists (ETRAs) on skin fibrosis in systemic sclerosis (SSc) patients from the (EULAR Scleroderma Trials and Research) EUSTAR cohort.

Methods

SSc patients from the EUSTAR cohort with at least three visits (pre-study visit without ETRA treatment, baseline and follow-up visit with ETRA treatment) were included. The control group consisted of SSc patients with the same inclusion criteria, but without ETRA treatment. The primary endpoint was the comparison of the delta change of the modified Rodnan skin score (mRSS) between baseline and follow-up in the ETRA versus the control group.

Results

Data on 75 ETRA treated (68 bosentan, 1 sitaxentan, 6 ambrisentan) and 969 control patients were included. The delta change of mRSS was not significantly different between the ETRA group and the control group (n = 969; 0 (-2-1) vs. n = 75; 0 (-2-1); p = 0.4). Similarly, subgroup analysis on patients with diffuse, extended SSc disease (mRSS ≥16) did not show differences in the delta change of mRSS between the ETRA group and the control group (n = 125; −1 [-7-0] vs. n = 23; −1 [-7-2], p = 0.8). Likewise, diffuse SSc patients with mRSS 7-21 at baseline, reflecting recently identified enrichment criteria for clinical trials, did not show any difference between the ETRA and the control group (n = 219; −1 [-3-1] vs. n = 27; −1 [-3-2]; p = 0.5).

Conclusions

This controlled, observational, real-life cohort study with a large sample size did not show effects of ETRAs on skin fibrosis in patients with SSc.

Intestinal Fibrosis and Liver Fibrosis: Consequences of Chronic Inflammation or Independent Pathophysiology?

Background

Intestinal fibrosis and liver fibrosis represent a significant burden for our patients and health-care systems. Despite the severe clinical problem and the observation that fibrosis is reversible, no specific antifibrotic therapies exist.

Summary

In this review, using an 'East-West' scientific collaboration, we summarize the current knowledge on principal mechanisms shared by intestinal fibrosis and liver fibrosis. We furthermore discuss inflammation as the cause of fibrogenesis in both entities, depict unique features of intestinal and hepatic fibrosis, and provide a future outlook on the development of antifibrotic therapies.

Key Messages

A collaborative effort in the field of fibrosis, covering multiple organ systems, will have the highest chance of leading to the development of a successful antifibrotic intervention.

Reversibility of Stricturing Crohn's Disease-Fact or Fiction?

Intestinal fibrosis is a common feature of Crohn's disease and may appear as a stricture, stenosis, or intestinal obstruction. Fibrostenosing Crohn's disease leads to a significantly impaired quality of life in affected patients and constitutes a challenging treatment situation. In the absence of specific medical antifibrotic treatment options, endoscopic or surgical therapy approaches with their potential harmful side effects are frequently used. However, our understanding of mechanisms of fibrogenesis in general and specifically intestinal fibrosis has emerged. Progression of fibrosis in the liver, lung, or skin can be halted or even reversed, and possible treatment targets have been identified. In face of this observation and given the fact that fibrotic alterations in various organs of the human body share distinct core characteristics, this article aims to address whether reversibility of intestinal fibrosis may be conceivable and to highlight promising research avenues and therapies.

Digital ulcers in scleroderma patients: A retrospective observational study

BACKGROUND

The guidelines for digital ulcers (DUs) management in systemic sclerosis (SSc) indicate the use of iloprost to induce wound healing and bosentan to prevent the onset of new DU. The aim of our study was to evaluate whether the combination treatment may surmount the effect of the single drug.

METHODS

We analyzed data regarding 34 patients with SSc and at least one active DU persisting despite 6 months of iloprost therapy, and treated for other 6 months with a combination therapy, i.e. iloprost plus bosentan.

RESULTS

Overall, patients initially presented 69 DUs (58 on the fingers and 11 on the legs). At the end of the study 34 (49.3%) DUs were completely healed (responding, R), 18 (26.1%) started the healing process (partially responding, PR), and 17 (24.6%) did not respond (NR) to therapy. No new DU was recorded and the ulcers localized on the legs did not respond to the combination therapy. Finally, data have been analyzed by dividing the patients in two groups according to the fibrosis level on the finger. In the group with mild fibrosis, 83.4% of DUs resulted with showing complete healing while, in the group with severe fibrosis, only 18% of DUs were healed (P = 0.024).

CONCLUSION

The treatment with iloprost plus bosentan is effective in determining healing of DUs in SSc patients with mild digital skin fibrosis. Conversely, the severity of skin fibrosis strongly influences the healing process of DUs. The study confirmed the efficacy of bosentan to prevent onset of new DUs.

Assessment of Central Corneal Thickness in Different Subtypes of Systemic Sclerosis

PURPOSE

To compare central corneal thickness between patients with diffuse cutaneous systemic sclerosis and limited cutaneous systemic sclerosis.

METHODS

A total of 53 consecutive patients with systemic sclerosis were enrolled in this study. All subjects were screened for age, gender, classification of disease subtype, autoantibody profile, duration of disease, organ involvement, current treatment, tear break-up time, Schirmer test, and measurement of the central corneal thickness with an ultrasonic pachymeter.

RESULTS

No statistically significant differences were found in terms of age, sex, and duration of the disease, and dry eye evaluation between systemic sclerosis subsets. The mean central corneal thickness was 535.3 ± 37.6 µm (range, 471-619 µm) in diffuse cutaneous systemic sclerosis patients, and 539.3 ± 37.1 µm (range, 484-651 µm) in limited cutaneous systemic sclerosis (p = 0.71).

CONCLUSIONS

Central corneal thickness in patients with diffuse cutaneous systemic sclerosis is not different from the one in limited cutaneous systemic sclerosis.

Amelioration of bleomycin-induced pulmonary fibrosis in a mouse model by a combination therapy of bosentan and imatinib

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) is characterized by alveolitis, progressing into fibrosis. Due to the involvement of both endothelin and platelet-derived growth factor signaling in IPF, combination effects of a bosentan and imatinib were studied in mouse model of bleomycin-induced pulmonary fibrosis.

METHODS

Mice subjected to bleomycin instillation (0.05 U) and were administered with either bosentan (100 mg/kg) and/or imatinib (50 mg/kg). Inflammatory cell count, total protein estimation in bronchoalveolar lavage fluid, lung edema, superoxide dismutase, catalase, myeloperoxidase activities, and Hematoxylin & Eosin staining were performed on day 7. Hydroxyproline content, α-smooth muscle actin (SMA), collagens I and III gene expression analysis, immunohistochemistry, matrix metalloproteinases-9 and -2 activities, trichrome and sirius red staining were performed on day 21.

RESULTS

Combination treatment with bosentan and imatinib prevented bleomycin-induced mortality and loss of body weight more than the individual agents. On day 7, the combination therapy attenuated bleomycin-induced increase of total and differential inflammatory cell counts, total proteins, lung wet/dry weight ratio, myeloperoxidase activity, lung inflammatory cell infiltration more than individual agents alone. Bosentan but not imatinib ameliorated superoxide dismutase and catalase activities, which were lowered following bleomycin instillation. On day 21, combination therapy ameliorated bleomycin-induced increase of fibrosis score, collagen deposition, protein and gene expression of SMA, mRNA levels of collagens-I and -III, matrix metalloproteinase-9 and -2 activities more than monotherapy.

CONCLUSION

Combination of bosentan and imatinib exerted more enhanced protection against bleomycin-induced inflammation and fibrosis than either of the agents alone.

Effects of macitentan and its active metabolite on cultured human systemic sclerosis and control skin fibroblasts

OBJECTIVE

To investigate the effects of the endothelin 1 (ET-1) receptor antagonists (ETRA) macitentan, its active metabolite ACT-132577, and bosentan on myofibroblast activation and extracellular matrix production induced by ET-1 in cultured systemic sclerosis (SSc) and control skin fibroblasts.

METHODS

Fibroblasts were obtained from skin biopsies of 6 patients with SSc and 5 healthy subjects. Some cultured cells were untreated or treated with macitentan, ACT-132577, or bosentan alone (10 μM). Other cultured cells were treated with ET-1 alone (100 nM) or with ETRA, and after 1 h, also with ET-1. After 48 h of treatment, myofibroblast activation was investigated to evaluate the α-smooth muscle actin (α-SMA) expression by immunofluorescence; type I collagen (COL-1) and fibronectin (FN) were investigated by immunocytochemistry, Western blotting, and quantitative real-time PCR (qRT-PCR). Statistical analysis was performed by the nonparametric Mann-Whitney U test.

RESULTS

In cultured SSc skin fibroblasts, only the treatment with macitentan significantly reduced the basal level of α-SMA expression (p = 0.03 vs untreated cells). Macitentan also significantly reduced the basal level of COL-1 synthesis, similarly to bosentan (p < 0.05 vs untreated cells). Macitentan or ACT-132577 antagonized the ability of ET-1 to further induce α-SMA expression (p = 0.03), COL-1, and FN synthesis (p = 0.03, p = 0.005); bosentan showed similar effects. These results obtained by immunofluorescence and immunocytochemistry were confirmed by Western blotting and qRT-PCR. The downregulatory effects exerted by ETRA were observed also in cultured human control skin fibroblasts.

CONCLUSION

Macitentan and ACT-132577 seem to downregulate in vitro the profibrotic myofibroblast phenotype induced by ET-1 in cultured human SSc skin fibroblasts.

Skin imaging in systemic sclerosis

Fibrotic involvement of the skin is a cardinal feature of systemic sclerosis (SSc). The extent of skin involvement is associated with internal organ involvement, coinciding with more severe disease course and poor prognosis. A palpation-based semi-quantitative score, the modified Rodnan skin score, is widely used for the assessment of skin involvement, but it is entailed by significant limitations. More objective approaches to measure skin involvement employing imaging have been explored continuously in the past decades and are currently advancing. Here, we review the use of different imaging techniques for the assessment of skin involvement in patients with SSc, focusing mainly on ultrasound, magnetic resonance imaging, and optical coherence tomography.

Effect of menopause on the modified Rodnan skin score in systemic sclerosis

Introduction

We aimed to evaluate the effect of menopause on skin thickening, as measured by the modified Rodnan skin score (mRSS), in women with systemic sclerosis (SSc).

Methods

We identified women with either limited or diffuse SSc, aged ≥ 18 years, enrolled within the Canadian Scleroderma Research Group (CSRG) cohort, between 2004 and 2011. As part of the CSRG cohort, subjects undergo annual assessments with standardized questionnaires and physical examinations. We performed multivariate regression analyses using generalized estimating equation (GEE) to determine the effect of menopause on the mRSS, adjusting for relevant covariates including notably age, follow-up time, and disease duration.

Results

We identified 1070 women with SSc, contributing a total of 3546 observations over the study period. Of these women, at baseline, 65% had limited disease and 35% diffuse disease. In multivariate analyses, we observed a substantial effect of postmenopausal status on the mean mRSS in women with diffuse disease subtype [−2.62 units, 95% confidence interval (CI) -4.44, −0.80] and significant interaction between menopausal status and disease subtype (2.04 units, 95% CI 0.20, 3.88). The effect of postmenopausal status on the mean mRSS was smaller in women with limited SSc (−0.58, 95% CI −1.50, 0.34).

Conclusions

Our results suggest that menopause has a substantial effect on skin thickening in diffuse SSc, with postmenopausal status being associated with a lower mean mRSS compared to premenopausal status.

Medical therapy of stricturing Crohn's disease: what the gut can learn from other organs - a systematic review

Crohn’s disease (CD) is a chronic remitting and relapsing disease. Fibrostenosing complications such as intestinal strictures, stenosis and ultimately obstruction are some of its most common long-term complications. Despite recent advances in the pathophysiological understanding of CD and a significant improvement of anti-inflammatory therapeutics, medical therapy for stricturing CD is still inadequate. No specific anti-fibrotic therapy exists and the incidence rate of strictures has essentially remained unchanged. Therefore, the current therapy of established fibrotic strictures comprises mainly endoscopic dilation as well as surgical approaches. However, these treatment options are associated with major complications as well as high recurrence rates. Thus, a specific anti-fibrotic therapy for CD is urgently needed. Importantly, there is now a growing body of evidence for prevention as well as effective medical treatment of fibrotic diseases of other organs such as the skin, lung, kidney and liver. In face of the similarity of molecular mechanisms of fibrogenesis across these organs, translation of therapeutic approaches from other fibrotic diseases to the intestine appears to be a promising treatment strategy. In particular transforming growth factor beta (TGF-β) neutralization, selective tyrosine kinase inhibitors, blockade of components of the renin-angiotensin system, IL-13 inhibitors and mammalian target of rapamycin (mTOR) inhibitors have emerged as potential drug candidates for anti-fibrotic therapy and may retard progression or even reverse established intestinal fibrosis. However, major challenges have to be overcome in the translation of novel anti-fibrotics into intestinal fibrosis therapy, such as the development of appropriate biomarkers that predict the development and accurately monitor therapeutic responses. Future clinical studies are a prerequisite to evaluate the optimal timing for anti-fibrotic treatment approaches, to elucidate the best routes of application, and to evaluate the potential of drug candidates to reach the ultimate goal: the prevention or reversal of established fibrosis and strictures in CD patients.

Expansion of range of joint motion following treatment of systemic sclerosis with tocilizumab

Systemic sclerosis (SSc) presents stiffness of extremities due to sclerosis of the tissue especially at fingers, hands, and forearms. Here we report the case of a patient with diffuse cutaneous SSc who was administered anti-interleukin-6 receptor antibody tocilizumab (TCZ). Skin condition of SSc is evaluated by pinching the skin according to the Rodnan skin score, but sometimes tissue atrophy results in overestimation of the condition. To understand how the extremities softened after initiation of TCZ, we observed mobility of extremities. Range of motion (ROM) of joints was measured every four months after initiation of TCZ. The patient presented not only reduction of Rodnan score but also amelioration of mobility of extremities. The Rodnan skin score reduced from 35 to 7 within sixteen months, and ROM of most joints except ankle was expanded.

Targeted therapies for systemic sclerosis

Pathogenic processes that underlie the development and progression of systemic sclerosis (SSc) are being defined in preclinical, clinical and genetic studies. Important evidence of interplay between the vasculature, connective tissue and specialized epithelial structures is emerging, and abnormalities of both the innate and adaptive immune systems have been identified. In this context, information regarding pivotal mediators, pathways or cell types that could be targets for therapeutic intervention, and that might offer potential for true disease modification, is accruing. Precedent for the regression of some aspects of the pathology has been set in clinical studies showing that potential exists to improve tissue structure and function as well as to prevent disease progression. This article reviews the concept of targeted therapies and considers potential pathways and processes that might be attenuated by therapeutic intervention in SSc. As well as improving outcomes, such approaches will undoubtedly provide information about pathogenesis. The concept of translational medicine is especially relevant in SSc, and we anticipate that the elusive goal of an effective antifibrotic treatment will emerge from one of the several clinical trials currently underway or planned in this disease. Therapeutic advances in SSc would have implications and potential beyond autoimmune rheumatic diseases.

Emerging targeted therapies in scleroderma lung and skin fibrosis

Systemic sclerosis (SSc) is a multisystemic fibrotic disorder that affects the skin and internal organs. Despite an improved outcome probably reflecting a better management of disease complications, morbidity and mortality remain higher than those of patients with other connective tissue diseases. SSc is still considered incurable; however, during recent years, intensive research activities have deepened the understanding of pathogenic mechanisms and have led to the identification of cellular and molecular anti-fibrotic targets. This review article will discuss potential future targeted therapeutic options based on data from in vitro studies, experimental models of fibrosis and first human trials with focus on scleroderma skin and lung fibrosis.

Clinical trials with endothelin receptor antagonists: what went wrong and where can we improve?

In the early 1990s, within three years of cloning of endothelin receptors, orally active endothelin receptor antagonists (ERAs) were tested in humans and the first clinical trial of ERA therapy in humans was published in 1995. ERAs were subsequently tested in clinical trials involving heart failure, pulmonary arterial hypertension, resistant arterial hypertension, stroke/subarachnoid hemorrhage and various forms of cancer. The results of most of these trials - except those for pulmonary arterial hypertension and scleroderma-related digital ulcers - were either negative or neutral. Problems with study design, patient selection, drug toxicity, and drug dosing have been used to explain or excuse failures. Currently, a number of pharmaceutical companies who had developed ERAs as drug candidates have discontinued clinical trials or further drug development. Given the problems with using ERAs in clinical medicine, at the Twelfth International Conference on Endothelin in Cambridge, UK, a panel discussion was held by clinicians actively involved in clinical development of ERA therapy in renal disease, systemic and pulmonary arterial hypertension, heart failure, and cancer. This article provides summaries from the panel discussion as well as personal perspectives of the panelists on how to proceed with further clinical testing of ERAs and guidance for researchers and decision makers in clinical drug development on where future research efforts might best be focused.

Potential immunologic targets for treating fibrosis in systemic sclerosis: a review focused on leukocytes and cytokines

OBJECTIVES

Systemic sclerosis (SSc) is a connective tissue disease characterized by tissue fibrosis. Although the pathogenesis remains unclear, a variety of cells contribute to the fibrotic process via interactions with each other and production of various cytokines. Recent literature related to the immunologic pathogenesis and future strategies for treating the fibrosis of SSc are discussed and, especially, this literature-based review that includes the authors' perspective, focused on leukocytes and cytokines.

METHODS

A PubMed search for articles published between January 2005 and January 2012 was conducted using the following keywords: systemic sclerosis, leukocyte, cytokine, growth factor, and chemokine. The reference lists of identified articles were searched for further articles.

RESULTS

Targeting profibrogenic cytokines, including transforming growth factor-β, is still a very active area of research in SSc and most cellular studies have focused on the roles of fibroblasts in SSc. However, a growing number of recent studies indicate a role for B cells in the development of SSc and other autoimmune diseases such as systemic lupus erythematosus. Therefore, B-cell-targeted therapies, including currently available monoclonal antibodies against CD19, CD20, CD22, and B-cell-activating factor, belonging to the tumor necrosis factor family represent possible treatment options. Furthermore, the modulation of T-cell costimulatory molecules such as a recombinant fusion protein of cytotoxic T-lymphocyte antigen-4 may be as effective in SSc as it is in treating other autoimmune diseases. Approaches to antagonize interleukin (IL)-1, IL-6, or IL-17A signaling may also be attractive.

CONCLUSIONS

This review describes recent advances in the treatment of fibrosis in SSc patients focused on immunologic strategies, such as leukocyte- or cytokine-targeted therapies.

Endothelin Receptor Antagonists for the Treatment of Raynaud's Phenomenon and Digital Ulcers in Systemic Sclerosis

Systemic sclerosis is a connective tissue disease characterized by fibrosis of the skin, internal organs, and widespread vasculopathy. Raynaud's phenomenon and digital ulcers are vascular manifestations of this disease and cause significant morbidity. Current treatments are only moderately effective in reducing the severity of Raynaud's in a portion of patients and typically do not lead to substantial benefit in terms of the healing or prevention of digital ulcers. Several studies have evaluated the efficacy of targeting the vasoconstrictor endothelin-1 for the treatment of systemic sclerosis-associated vascular disease. The purpose of this paper is to summarize the published studies and case reports evaluating the efficacy of endothelin receptor antagonists in the treatment of Raynaud's phenomenon and digital ulcers associated with systemic sclerosis.

Vascular changes in bleomycin-induced scleroderma

Systemic sclerosis (SSc) is characterized by vascular injury, immunological abnormalities, and fibrosis of the skin as well as various internal organs. Vascular impairment is the early manifestation and plays a fundamental role in the pathogenesis of SSc. Recent studies suggest that complex interactions among the endothelial cells, pericytes, smooth muscle cells, and fibroblasts are involved in the systemic vasculopathy in SSc, and histological feature of proliferation of vascular wall is seen in the lesional scleroderma skin at the late stage of disease. One of the most representative mouse models for scleroderma is the bleomycin-induced scleroderma; however, aspects of vascular alteration have not been described in detail so far. A number of studies have shown that bleomycin stimulates endothelial cells and fibroblasts to induce proinflammatory and fibrogenic cytokines, apoptosis, reactive oxygen species, and so on. This paper makes a focus on the vascular involvement in the bleomycin-induced murine scleroderma.

Effect of Bosentan on systemic sclerosis-associated interstitial lung disease ineligible for cyclophosphamide therapy: a prospective open-label study

OBJECTIVE

To evaluate the clinical benefits of the endothelin receptor antagonist bosentan on interstitial lung disease (ILD) in patients with systemic sclerosis (SSc) who are ineligible for cyclophosphamide (CYC) therapy.

METHODS

In this prospective open-label study, 9 patients with SSc and ILD received bosentan for 24 months. The main reasons for avoiding CYC included severely impaired lung function, long disease duration, and relapse after CYC treatment. Pulmonary function tests and Doppler echocardiograms were evaluated every 6 months, and high-resolution computed tomography (HRCT) was performed every 12 months. For an extended survival analysis, 17 historical controls who met the inclusion criteria at referral and had not used any immunosuppressive or antifibrotic agents thereafter were selected from the SSc database.

RESULTS

Two patients did not finish the study; one developed vasculitis requiring high-dose corticosteroids and another died of bacterial pneumonia. The remaining 7 patients tolerated bosentan and completed the study period. There were trends toward mildly reduced forced vital capacity, total lung capacity, and diffusing capacity for carbon monoxide over time. Two patients developed pulmonary hypertension during the 24-month period. HRCT scores for ground-glass opacity, pulmonary fibrosis, and honeycomb cysts gradually increased. In the extended study, there was no difference in cumulative survival rate between the bosentan-treated and historical control groups.

CONCLUSION

The gradual worsening of pulmonary function and HRCT findings in patients treated with bosentan was consistent with the natural course of SSc-associated ILD. This study does not support the use of bosentan for SSc-associated ILD even when CYC treatment is inadvisable.

Bosentan treatment for Raynauds phenomenon and skin fibrosis in patients with Systemic Sclerosis and pulmonary arterial hypertension: an open-label, observational, retrospective study

Raynaud?s phenomenon (RP) and cutaneous fibrosis are the distinctive manifestations of scleroderma, in which Endothelin-1 plays a fundamental pathogenetic role. Bosentan, an Endothelin-1 receptor antagonist used for the treatment of pulmonary arterial hypertension, retards the beginning of new sclerodermic digital ulcers (DU). This open-label, observational, retrospective study verified the effect of Bosentan on RP and skin fibrosis in sclerodermic outpatients affected by pulmonary arterial hypertension without DU. Fourteen subjects (13 women, 1 man; mean age 60 ± 7.5 years; ten with limited and four with diffuse scleroderma) were observed at baseline (T0) and after four (T1), twelve (T2), twenty-four (T3) and forty-eight (T4) weeks during treatment with Bosentan. They were evaluated for daily quantity and duration of RP attacks and skin thickness (using modified Rodnan total skin score, MRSS). Videocapillaroscopic evaluation was performed at T0 and T4. Bosentan decreased significantly the number and duration of RP attacks, beginning at T2 (p<0.05). Videocapillaroscopy showed significant improvement of microcirculatory patterns at T4 (p<0.05). MRSS decreased throughout the study, reaching the statistical significance at T3 and T4 (p<0.01) in the whole cohort. The present data suggest that Bosentan is effective in stabilizing the microcirculation involvement and in improving skin fibrosis irrespective of scleroderma patterns.

Possible strategies for anti-fibrotic drug intervention in scleroderma

There are no approved drugs for treating the fibrosis in scleroderma (systemic sclerosis, SSc). Myfibroblasts within connective tissue express the highly contractile protein α-smooth muscle actin (α-SMA) and are responsible for the excessive synthesis and remodeling of extracellular matrix (ECM) characterizing SSc. Drugs targeting myofibroblast differentiation, recruitment and activity are currently under consideration as anti-fibrotic treatments in SSc but thus far have principally focused on the transforming growth factor β (TGFβ), endothelin-1 (ET-1), connective tissue growth factor (CCN2/CTGF) and platelet derived growth factor (PDGF) pathways, which display substantial signaling crosstalk. Moreover, peroxisome proliferator-activated receptor (PPAR)γ also appears to act by intervening in TGFβ signaling. This review discusses these potential candidates for antifibrotic therapy in SSc.

Towards an anti-fibrotic therapy for scleroderma: targeting myofibroblast differentiation and recruitment

BACKGROUND

In response to normal tissue injury, fibroblasts migrate into the wound where they synthesize and remodel new extracellular matrix. The fibroblast responsible for this process is called the myofibroblast, which expresses the highly contractile protein alpha-smooth muscle actin (alpha-SMA). In normal tissue repair, the myofibroblast disappears. Conversely, abnormal myofibroblast persistence is a key feature of fibrotic dieases, including scleroderma (systemic sclerosis, SSc). Myofibroblasts can be derived from differentiation of local resident fibroblasts or by recruitment of microvascular pericytes.

CLINICAL PROBLEM ADDRESSED

Controlling myofibroblast differentiation and persistence is crucial for developing anti-fibrotic therapies targeting SSc.

BASIC SCIENCE ADVANCES

Insights have been recently generated into how the proteins transforming growth factor beta (TGFbeta), endothelin-1 (ET-1), connective tissue growth factor (CCN2/CTGF) and platelet derived growth factor (PDGF) contribute to myofibroblast differentiation and pericyte recruitment in general and to the persistent myofibroblast phenotype of lesional SSc fibroblast, specifically.

RELEVANCE TO CLINICAL CARE

This minireview summarizes recent findings pertinent to the origin of myofibroblasts in SSc and how this knowledge might be used to control the fibrosis in this disease.

CONCLUSIONS

TGFbeta, ET-1, CCN2 and PDGF are likely to cooperate in driving tissue repair and fibrogenic responses in fibroblasts. TGFbeta, ET-1 and CCN2 appear to contribute to myofibroblast differentiation; PDGF appears to be involved with pericyte recruitment. Thus, different therapeutic strategies may exist for targeting the multisystem fibrotic disorder SSc.