Scleroderma and related disorders: therapeutic aspects

Relaxin in fibrotic ligament diseases: Its regulatory role and mechanism

Fibrotic ligament diseases (FLDs) are diseases caused by the pathological accumulation of periarticular fibrotic tissue, leading to functional disability around joint and poor life quality. Relaxin (RLX) has been reported to be involved in the development of fibrotic lung and liver diseases. Previous studies have shown that RLX can block pro-fibrotic process by reducing the excess extracellular matrix (ECM) formation and accelerating collagen degradation in vitro and in vivo. Recent studies have shown that RLX can attenuate connective tissue fibrosis by suppressing TGF-β/Smads signaling pathways to inhibit the activation of myofibroblasts. However, the specific roles and mechanisms of RLX in FLDs remain unclear. Therefore, in this review, we confirmed the protective effect of RLX in FLDs and summarized its mechanism including cells, key cytokines and signaling pathways involved. In this article, we outline the potential therapeutic role of RLX and look forward to the application of RLX in the clinical translation of FLDs.

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.

Tissue Doppler Echocardiography and Myocardial Performance Index in Patients with Scleroderma

In this study, left and right ventricular functions were examined echocardiographically in 22 patients with scleroderma and 22 healthy volunteers. Conventional and tissue Doppler echocardiography and myocardial performance indexes were used as measures of right and left ventricular global functions. Mitral early diastolic E wave deceleration time, isovolumetric contraction time and left ventricular myocardial performance index and peak tricuspid A wave velocity were significantly higher in the scleroderma group compared with the control group. Mitral and tricuspid E/A ratios were significantly lower in patients with scleroderma. In addition, mitral annular and tricuspid annular isovolumetric relaxation times and the tricuspid E/E' ratio were significantly increased in scleroderma patients compared with the control group. In conclusion, in scleroderma patients the global left ventricular functions were depressed and diastolic function abnormalities were seen in both right and left ventricles. In addition, longitudinal muscle functions of the ventricles were depressed in scleroderma patients, as shown by tissue Doppler imaging parameters.

Cardiac manifestations in systemic sclerosis

Primary cardiac involvement, which develops as a direct consequence of systemic sclerosis (SSc), may manifest as myocardial damage, fibrosis of the conduction system, pericardial and, less frequently, as valvular disease. In addition, cardiac complications in SSc may develop as a secondary phenomenon due to pulmonary arterial hypertension and kidney pathology. The prevalence of primary cardiac involvement in SSc is variable and difficult to determine because of the diversity of cardiac manifestations, the presence of subclinical periods, the type of diagnostic tools applied, and the diversity of patient populations. When clinically manifested, cardiac involvement is thought to be an important prognostic factor. Profound microvascular disease is a pathognomonic feature of SSc, as both vasospasm and structural alterations are present. Such alterations are thought to predict macrovascular atherosclerosis over time. There are contradictory reports regarding the prevalence of atherosclerosis in SSc. According to some authors, the prevalence of atherosclerosis of the large epicardial coronary arteries is similar to that of the general population, in contrast with other rheumatic diseases such as rheumatoid arthritis and systemic lupus erythematosus. However, the level of inflammation in SSc is inferior. Thus, the atherosclerotic process may not be as aggressive and not easily detectable in smaller studies. Echocardiography (especially tissue Doppler imaging), single-photon emission computed tomography, magnetic resonance imaging and cardiac computed tomography are sensitive techniques for earlier detection of both structural and functional scleroderma-related cardiac pathologies. Screening for subclinical cardiac involvement via modern, sensitive tools provides an opportunity for early diagnosis and treatment, which is of crucial importance for a positive outcome.

The scleroderma kidney: progress in risk factors, therapy, and prevention

Scleroderma renal crisis (SRC) is characterized by malignant hypertension, oliguric/anuric acute renal failure, and important mortality, with a 5-year survival rate of 65%. SRC occurs in 2% to 5% of patients with systemic sclerosis (SSc), particularly those with diffuse cutaneous SSc in the first years of disease evolution. Several retrospective studies have found high-dose corticosteroid therapy to be associated with increased risk of SRC, and anti-RNA-polymerase III antibodies have been detected in one third of patients with SRC. Treatment relies on the early control of blood pressure with increasing doses of angiotensin-converting enzyme inhibitors, eventually associated with calcium channel blockers together with dialysis if necessary. After 2 years on dialysis, eligible patients should be considered for renal transplantation. The strategy for prevention of SRC lacks consensus. However, corticosteroids and/or nephrotoxic drugs should be avoided in patients with diffuse cutaneous SSc.

Observational Study of Treatment Outcome in Early Diffuse Cutaneous Systemic Sclerosis

Objective.

Randomized clinical trials in early diffuse cutaneous systemic sclerosis (dcSSc) are challenging. We used an observational approach to estimate the relative effectiveness of different current treatment approaches, capturing entry and outcome data in a standardized way.

Methods.

Patients with dcSSc within 3 years of the onset of skin thickening were included. Standardized entry and followup data were collected in relation to the first disease-modifying treatment at baseline and 4–6 weeks, then 3, 6, 12, 18, 24, 30, and 36 months. The 5 different protocols were (1) intravenous cyclophosphamide followed by mycophenolate mofetil (MMF); (2) antithymocyte globulin followed by MMF; (3) MMF alone; (4) no disease-modifying treatment; (5) other immunosuppressant treatment. The primary outcome measure was the modified Rodnan skin score (mRSS). Inverse probability of treatment weights were used to allow for differing patient characteristics between groups.

Results.

The study included 147 patients from 12 centers. Numbers of patients starting on Protocols 1 to 5 were 29, 25, 61, 19, and 13, respectively. mRSS decreased over time from 24 (IQ 19–32) at baseline to 15.5 (IQ 9–24.5) at 3 years. Although there were differences in the magnitude of the change for different protocols, there were no significant differences between protocols in the rate of change of mRSS over time (p = 0.43). When inverse probability weights were applied, the results remained nonsignificant (p = 0.41).

Conclusion.

Using this observational approach, there were no obvious differences in outcome between groups after allowing as far as possible for baseline differences in treatment allocations.

Digital ulcers: overt vascular disease in systemic sclerosis

RP is an almost universal manifestation of SSc, with 95% of all patients being affected, and resulting in digital ulcers (DUs) in approximately 30% of the patients each year. DUs are a major clinical problem, being associated with substantial morbidity (reduced quality of life, pain, disability and disfigurement) that can escalate to gangrene and amputation. Ideally, the treatment of DUs would improve tissue integrity and viability, promote ulcer healing and reduce the formation of new ulcers. Treatments that have shown potential include calcium channel blockers, prostacyclin analogues and endothelin receptor antagonists. However, until recently, management was based on empirical experience. The recent approval (in Europe) of the dual endothelin receptor antagonist, bosentan, to reduce the number of new DUs in patients with SSc and ongoing DU disease, means that there is now an approved therapy--and new hope--for the treatment of DUs in these severely afflicted patients.

Gastrointestinal manifestations of systemic sclerosis

Systemic sclerosis is a chronic disorder of connective tissue that affects the gastrointestinal tract in more than 80% of patients. Changes in neuromuscular function with progressive fibrosis of smooth muscle within the muscularis propria impair normal motor function, which may secondarily alter transit and nutrient absorption. Esophageal manifestations with gastroesophageal reflux and dysphagia are the most common visceral manifestation of the disease, often requiring more intense acid-suppressive medication. Gastric involvement may lead to gastroparesis, which can be found in up to 50% of patients. Severe small bowel disease can present as chronic intestinal pseudo-obstruction with distended loops of small intestine, bacterial overgrowth, impaired absorption and progressive development of nutritional deficiencies. While not studied as extensively, systemic sclerosis often also affects colorectal function resulting in constipation, diarrhea or fecal incontinence. Nutritional support and prokinetics have been used with some success to manage gastric and small or large bowel involvement in patients with systemic sclerosis. Despite advances in management, significant gastrointestinal manifestations of systemic sclerosis still carry a poor prognosis with a five-year mortality exceeding 50%.

Long-term effects of bosentan on quality of life, survival, safety and tolerability in pulmonary arterial hypertension related to connective tissue diseases

OBJECTIVES

This study investigated the long-term effects of bosentan, an oral endothelin ET(A)/ET(B) receptor antagonist, in patients with pulmonary arterial hypertension (PAH) exclusively related to connective tissue diseases (CTD).

METHODS

A total of 53 patients with PAH related to connective tissue diseases (PAH-CTD) in World Health Organization (WHO) functional class III received bosentan 62.5 mg twice a day for 4 weeks and then 125 mg twice a day for 44 weeks in this open non-comparative study. Assessments at weeks 16 and 48 included WHO class, clinical worsening, quality of life (Short-Form Health Survey (SF-36) and health assessment questionnaire (HAQ) modified for scleroderma), and survival (week 48 only). Safety and tolerability were monitored throughout the study.

RESULTS

At week 48, WHO class improved in 27% of patients (95% CI 16-42%) and worsened in 16% (95% CI 7-29%). Kaplan-Meier estimates were 68% (95% CI 55-82%) for absence of clinical worsening and 92% (95% CI 85-100%) for survival. Overall changes in quality of life were minimal. There were no unexpected side effects observed during the study.

CONCLUSIONS

In most patients, bosentan was associated with improvement or stability of clinical status. The 92% estimate for survival at 48 weeks is a significant achievement in this patient population.

[Scleroderma renal crisis]

Scleroderma renal crisis (SRC) occurs in patients with systemic sclerosis (SSc) and is defined by otherwise unexplained rapidly progressive renal insufficiency associated with oliguria or rapidly progressive arterial hypertension or both. SRC is a rare and severe complication of SSc, most often encountered during the first 4 years of disease, almost only in patients with diffuse SSc. Factors predicting SRC were identified, including high-dose corticosteroid administration. Use of angiotensin-converting enzyme inhibitors (ACEI) has dramatically impressed the prognosis of SRC, but it mortality rate is still high. Treatment aims at normalizing blood pressure as soon as possible. ACEI should always be used, and additional anti-hypertensive agents, including calcium channel blockers and alpha- and beta-blockers, may be useful. Renal replacement therapy may be needed, but often (for almost half of patients) only temporarily.

The relaxin gene knockout mouse: a model of progressive scleroderma

Relaxin is a peptide hormone with anti-fibrotic properties. To investigate the long-term effects of relaxin deficiency on the ageing skin, we compared structural changes in the skin of ageing relaxin-deficient (RLX-/-) and normal (RLX+/+) mice, by biochemical, histological, and magnetic resonance imaging analyses. Skin biopsies from RLX+/+ and RLX-/- mice were obtained at different ages and analyzed for changes in collagen expression and distribution. We demonstrated an age-related progression of dermal fibrosis and thickening in male and female RLX-/- mice, associated with marked increases in types I and III collagen. The increased collagen was observed primarily in the dermis of RLX-/- mice by 1 mo of age, and eventually superseded the hypodermal layer. Additionally, fibroblasts from the dermis of RLX-/- mice were shown to produce increased collagen in vitro. Recombinant human gene-2 (H2) relaxin treatment of RLX-/- mice resulted in the complete reversal of dermal fibrosis, when applied to the early onset of disease, but was ineffective when applied to more established stages of dermal scarring. These combined findings demonstrate that relaxin provides a means to regulate excessive collagen deposition in disease states characterized by dermal fibrosis and with our previously published work demonstrate the relaxin-null mouse as a model of progressive scleroderma.

A new era in the management of pulmonary arterial hypertension related to scleroderma: endothelin receptor antagonism

Evidence suggests that endothelin may have a fundamental role in scleroderma pathogenesis, including pulmonary arterial hypertension (PAH)--a leading cause of death in patients with scleroderma. Development of a new class of drug, endothelin receptor antagonists, heralds an improved outlook for patients with scleroderma and related diseases. Heightened vigilance towards early detection of PAH in scleroderma and a multidisciplinary approach to diagnosis and treatment may improve clinical outcomes for these patients.

Update on disease-modifying antirheumatic drugs in the treatment of systemic sclerosis

Treatment of systemic sclerosis has been somewhat haphazard and treatment has often been "borrowed" from the experience gained from treating other connective tissue diseases. There was a period of time that was focused mainly on organ-specific manifestations of systemic sclerosis and some advance in preventing vital organ damage (such as renal crisis) was achieved. The vast improvement in mortality from the use of ACE inhibitors raises one's hopes for other effective therapeutic interventions. At this juncture, the evidence is strong that the ACE inhibitors that are used in scleroderma renal crisis are disease-modifying, even without proving it by a randomized controlled trial. The evidence is strong that the use of epoprostenol for primary pulmonary hypertension is life-saving; however, whether epoprostenol is life-saving in the pulmonary hypertension in scleroderma remains to be proven. There are suggestions that bosentan (for the pulmonary hypertension of scleroderma), cyclophosphamide (for SSc alveolitis), stem cell transplant, interferon-gamma (for interstitial pulmonary fibrosis), and methotrexate (for the skin thickening of diffuse scleroderma) may improve organ function or functional activities, but whether they are truly disease-modifying remains to be proven. As we increase our understanding of the pathophysiology of systemic sclerosis and we learn how better to design trials for systemic sclerosis, we may be more successful in developing optimal disease-modifying therapy. Although the treatment of systemic sclerosis remains difficult, there are an increasing number of potentially effective regimens that are undergoing clinical investigations. A rational approach to therapy seems possible, based on a hypothesis of the pathogenesis of systemic sclerosis. Thus, there is accumulating evidence that supports the use of prostacyclin derivatives to treat systemic sclerosis, some evidence that antifibrotic regimens may be effective, and moderate evidence that immunosuppression also may be effective in certain stages of this disease.

Development of agents for the treatment of systemic sclerosis

Systemic sclerosis (SSc) is a multisystem connective tissue disease characterised clinically by fibrosis and ischaemic atrophy. Internal organ involvement can be life-threatening. Although there are effective treatments for some of the organ-based manifestations of SSc, for example proton-pump inhibitors for upper gastrointestinal disease, no drug has so far been proven to modify the underlying disease process. Our increased understanding of the pathogenesis of SSc, which involves a complex interplay between excessive collagen production, vascular abnormalities and immune dysfunction, is directing development of drugs which hold promise as 'disease-modifying' agents. Some of the drugs under investigation for the treatment of SSc have already been used in other conditions which 'overlap' with SSc, for example primary pulmonary hypertension. Conversely, it is to be hoped that in the future, drugs shown to be effective in SSc might prove beneficial for other fibrotic diseases.