Pulmonary arterial hypertension in systemic sclerosis: clinical manifestations, pathophysiology, evaluation, and management

MiRNAs in Systemic Sclerosis Patients with Pulmonary Arterial Hypertension: Markers and Effectors

Background: Pulmonary arterial hypertension (PAH) is a major cause of death in systemic sclerosis (SSc). Early detection may improve patient outcomes. Methods: We searched for circulating miRNAs that would constitute biomarkers in SSc patients with PAH (SSc-PAH). We compared miRNA levels and laboratory parameters while evaluating miRNA levels in white blood cells (WBCs) and myofibroblasts. Results: Our study found: 1) miR-26 and miR-let-7d levels were significantly lower in SSc-PAH (n = 12) versus SSc without PAH (SSc-noPAH) patients (n = 25); 2) a positive correlation between miR-26 and miR-let-7d and complement-C3; 3) GO-annotations of genes that are miR-26/miR-let-7d targets and that are expressed in myofibroblast cells, suggesting that these miRNAs regulate the TGF-β-pathway; 4) reduced levels of both miRNAs accompanied fibroblast differentiation to myofibroblasts, while macitentan (endothelin receptor-antagonist) increased the levels. WBCs of SSc-noPAH and SSc-PAH patients contained equal amounts of miR-26/miR-let-7d. During the study, an echocardiograph that predicted PAH development, showed increased pulmonary artery pressure in three SSc-noPAH patients. At study initiation, those patients and an additional SSc-noPAH patient, who eventually developed PAH, had miR-let-7d/miR-26 levels similar to those of SSc-PAH patients. This implies that reduced miR-let-7d/miR-26 levels might be an early indication of PAH. Conclusions: miR-26 and miR-let-7d may be serological markers for SSc-PAH. The results of our study suggest their involvement in myofibroblast differentiation and complement pathway activation, both of which are active in PAH development.

'Narrow-sense' and 'broad-sense' vascular abnormalities of systemic sclerosis

Systemic sclerosis (SSc) induces skin thickening and numerous symptoms involving the entire body. Collagen deposition, immune disorder, and vascular abnormalities is currently estimated to be three major causal factors involved in the respective conditions. Vascular abnormalities usually develop in the initial phase of this disease, and may exist in all phases; therefore, they markedly influence the patient's quality of life. This article reviews recent findings about 'narrow-sense' vascular lesions (including Raynaud's phenomenon, skin ulcers, nailfold bleedings, pitting scars, telangiectasia, and pulmonary hypertension) and 'broad-sense' vascular lesions (such as calcinosis or erectile dysfunction). Affected blood vessels can be classified into arteriole/small artery and capillary blood vessels. Furthermore, pathological changes include the proliferation of the vascular endothelial or smooth muscle cells, lumen stenosis by collagen accumulation of the vascular intima, vasodilation or fragility, and apoptosis. There may be interaction between vascular lesions, autoimmune disorder, and collagen deposition. Thus, various symptoms of this disease may be controlled through the treatment of vascular lesions.

Genetic susceptibility loci of idiopathic interstitial pneumonia do not represent risk for systemic sclerosis: a case control study in Caucasian patients

BACKGROUND

Systemic sclerosis (SSc)-related interstitial lung disease (ILD) has phenotypic similarities to lung involvement in idiopathic interstitial pneumonia (IIP). We aimed to assess whether genetic susceptibility loci recently identified in the large IIP genome-wide association studies (GWASs) were also risk loci for SSc overall or severity of ILD in SSc.

METHODS

A total of 2571 SSc patients and 4500 healthy controls were investigated from the US discovery GWAS and additional US replication cohorts. Thirteen IIP-related selected single nucleotide polymorphisms (SNPs) were genotyped and analyzed for their association with SSc.

RESULTS

We found an association of SSc with the SNP rs6793295 in the LRRC34 gene (OR = 1.14, CI 95 % 1.03 to 1.25, p value = 0.009) and rs11191865 in the OBFC1 gene (OR = 1.09, CI 95 % 1.00 to 1.19, p value = 0.043) in the discovery cohort. Additionally, rs7934606 in MUC2 (OR = 1.24, CI 95 % 1.01 to 1.52, p value = 0.037) was associated with SSc-ILD defined by imaging. However, these associations failed to replicate in the validation cohort. Furthermore, SNPs rs2076295 in DSP (β = -2.29, CI 95 % -3.85 to -0.74, p value = 0.004) rs17690703 in SPPL2C (β = 2.04, CI 95 % 0.21 to 3.88, p value = 0.029) and rs1981997 in MAPT (β = 2.26, CI 95 % 0.35 to 4.17, p value = 0.02) were associated with percent predicted forced vital capacity (FVC%) even after adjusting for the anti-topoisomerase (ATA)-positive subset. However, these associations also did not replicate in the validation cohort.

CONCLUSIONS

Our results add new evidence that SSc and SSc-related ILD are genetically distinct from IIP, although they share phenotypic similarities.

Involvement of CD161+ Vδ1+ γδ T cells in systemic sclerosis: association with interstitial pneumonia

OBJECTIVE

Interstitial pneumonia (IP) is a chronic progressive interstitial lung disease associated with high mortality and poor prognosis. However, the pathogenesis of IP remains to be elucidated. The aim of this study was to clarify the role of CD161(+) Vδ1(+) γδ T cells in SSc patients with IP.

METHODS

The proportion of CD161(+) Vδ1(+) γδ T cells in peripheral blood mononuclear cells (PBMCs) and serum sialylated carbohydrate antigen (KL-6) levels were determined. GeneChip analysis was performed with CD161(-) and CD161(+) Vδ1(+) γδ T cells. Cytokine and chemokine expression from CD161(+) Vδ1(+) γδ T cells was measured and used to evaluate the effect of culture supernatant on fibroblast proliferation.

RESULTS

The proportion of CD161(+) Vδ1(+) γδ T cells was significantly higher in SSc than healthy controls (HCs) and correlated negatively with serum KL-6 levels in IP-positive SSc patients. The gene and mRNA expression level of chemokine ligand 3 (CCL3) was markedly higher in CD161(+) Vδ1(+) γδ T cells than in CD161(-) Vδ1(+) γδ T cells. CD161(+) Vδ1(+) γδ T cells in IP-positive SSc patients showed higher production of CCL3 and lower production of IFN-γ than in HCs. Culture supernatant derived from IP-negative and IP-positive SSc patients promoted fibroblast proliferation, whereas that from HCs did not.

CONCLUSION

The small proportion and the altered cell functions of CD161(+) Vδ1(+) γδ T cells among PBMCs in SSc patients play a role in the pathogenesis of IP. These findings suggest that CD161(+) Vδ1(+) γδ T cells may play a regulatory role in the pathogenesis of IP in SSc patients via IFN-γ production.

Role of endothelial to mesenchymal transition in the pathogenesis of the vascular alterations in systemic sclerosis

The pathogenesis of Systemic Sclerosis (SSc) is extremely complex, and despite extensive studies, the exact mechanisms involved are not well understood. Numerous recent studies of early events in SSc pathogenesis have suggested that unknown etiologic factors in a genetically receptive host trigger structural and functional microvascular endothelial cell abnormalities. These alterations result in the attraction, transmigration, and accumulation of immune and inflammatory cells in the perivascular tissues, which in turn induce the phenotypic conversion of endothelial cells and quiescent fibroblasts into activated myofibroblasts, a process known as endothelial to mesenchymal transition or EndoMT. The activated myofibroblasts are the effector cells responsible for the severe and frequently progressive fibrotic process and the fibroproliferative vasculopathy that are the hallmarks of SSc. Thus, according to this hypothesis the endothelial and vascular alterations, which include the phenotypic conversion of endothelial cells into activated myofibroblasts, play a crucial role in the development of the progressive fibrotic process affecting skin and multiple internal organs. The role of endothelial cell and vascular alterations, the potential contribution of endothelial to mesenchymal cell transition in the pathogenesis of the tissue fibrosis, and fibroproliferative vasculopathy in SSc will be reviewed here.

HLA markers for poor prognosis in systemic sclerosis Brazilian patients

Objectives. The aim of this study was to evaluate human leukocyte antigen (HLA) involvement in the disease expression and poor prognostic clinical features (pulmonary fibrosis and pulmonary arterial hypertension) in patients diagnosed with systemic sclerosis (SSc) in a multiethnic population. Methods. SSc patients followed up between 2008 and 2011 were included, and clinical data were obtained through records review. Molecular HLA typing was performed (polymerase chain reaction amplification technique using specific primer sequences). The statistical analysis involved Fisher's exact test and Pearson's corrected chi-square test. P  values ≤ 0.05 were considered significant. The delta method was used to estimate the variance of the prevalence ratio (PR). Results. A total of 141 patients (120 women and 21 men) with SSc were studied, including 33.3% with diffuse cutaneous SSc (dcSSc), 62.4% with limited cutaneous SSc (lcSSc), and 4.3% with sine scleroderma. Pulmonary fibrosis was present in 61 patients (43.3%), and the HLA-A∗30 and DQB1∗04 alleles were related to susceptibility. In contrast, the HLA-DRB1∗01 and DQB1∗05 alleles were protective. Pulmonary arterial hypertension was diagnosed in 19 patients (13.5%) and was associated with HLA-B∗35 and C∗04; in contrast, C∗03 seemed to be protective. Conclusions. Our current study documents the association of some classes I and II HLA alleles with the most severe clinical manifestations in a multiethnic case series. Our findings differed slightly from the previous data in other populations.

Bosentan fosters microvascular de-remodelling in systemic sclerosis

Bosentan, a dual endothelin receptor antagonist, may reduce blood pressure by blocking the vasoconstrictor effect of endothelin-1. In systemic sclerosis (SSc) nailfold videocapillaroscopy (NVC); allows diagnostic and follow-up of microvascular damage. Distinct NVC patterns have been identified for the evaluation of severity of SSc microvascular damage. The objective of this study is to evaluate the modification of the microvasculature under Bosentan therapy in SSc patients with pulmonary arterial hypertension (PAH). Nine patients with PAH related to SSc in New York Heart Association classes III-IV were treated with Bosentan 125 mg twice a day. NVC optical probe videocapillaroscopy equipped with 100× and 200× contact lenses and connected to image analyse software was performed before and after 12 months of Bosentan therapy to evaluate the modification of microvasculature. Nine PAH SSc patients treated with Iloprost were used as controls. Before Bosentan therapy, seven patients showed at NVC severe loss of capillaries with large avascular areas and vascular architectural disorganisation which are typically "late" SSc pattern. After 12 months of Bosentan, NVC pattern changed in seven patients from "late" into "active" SSc pattern. The disappearance of avascular areas and capillary haemorrhages was the most striking result. Two patients had an "active" SSc pattern, not modified by Bosentan treatment. These data show that Bosentan may improve NVC pattern in SSC and the presence of new capillaries suggests that it may favour angiogenesis. Bosentan may improve and stabilise the microvasculature in long-term treatment modulating the structural modifications detected by NVC.

Cardiac complications of systemic sclerosis: recent progress in diagnosis

PURPOSE OF REVIEW

Systemic sclerosis (SSc), a collagen vascular disease characterized by diverse organ system involvement, is associated with serious cardiac complications. Cardiac symptoms are much less frequent than autopsy-demonstrated cardiac involvement. Although frequent calls for early diagnosis have been made, validated strategies for assessment of scleroderma cardiac disease are not yet well established, mainly because the right ventricle, a common target of the disease, presents considerable obstacles to simple and reliable appraisal of its structure and function. This article reviews the current information about cardiac dysfunction in scleroderma, with special emphasis on its detection and prognostic implications.

RECENT FINDINGS

Cardiac involvement is a harbinger of poor prognosis in patients with SSc. Recent progress in its diagnosis has been made with the availability of more sophisticated diagnostic tools.

SUMMARY

Early detection of scleroderma heart disease will allow exploration of novel therapies with potential positive impact on the quality of life and life expectancy of this patient population.

Pneumonia intersticial associada à esclerose sistêmica: avaliação da função pulmonar no período de cinco anos

OBJETIVO: Avaliar as alterações da função pulmonar em portadores de pneumonia intersticial associada à esclerose sistêmica no intervalo de cinco anos. MÉTODOS: Foi realizado um estudo longitudinal no qual foram avaliados 35 pacientes não tabagistas com esclerose sistêmica e sem história de doença pulmonar prévia. Na primeira avaliação, realizada na época do diagnóstico da pneumonia intersticial, os pacientes foram submetidos à TCAR, espirometria e medida de DLCO. Os pacientes foram subdivididos em dois grupos de acordo com a presença ou não de faveolamento na TCAR. Aproximadamente cinco anos após a primeira avaliação, os pacientes foram submetidos a espirometria e medida da DLCO apenas. RESULTADOS: Dos 35 pacientes, 34 eram mulheres, com média de idade de 47,6 anos. A média de tempo entre as duas avaliações foi de 60,9 meses. O faveolamento foi demonstrado por TCAR em 17 pacientes. Na amostra total, após cinco anos do diagnóstico, CVF, VEF1 e DLCO reduziram significativamente (81,3 ± 18,2% vs. 72,1 ± 22,2%; 79,9 ± 17,8% vs. 72,5 ± 20,6%; e 74,0 ± 20,5% vs. 60,7 ± 26,8%, respectivamente; p = 0.0001 para todos), enquanto a relação VEF1/CVF aumentou significativamente (98,5 ± 7,2% vs. 101,9 ± 7,8%; p = 0,008). No mesmo período, os valores de CVF, VEF1 e DLCO foram significativamente menores nos pacientes com faveolamento do que naqueles sem faveolamento na TCAR (p = 0,0001). CONCLUSÕES: Na esclerose sistêmica com doença pulmonar intersticial associada, a detecção de faveolamento na TCAR é determinante para predizer uma deterioração acelerada da função pulmonar.

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.

Pulmonary hypertension in systemic sclerosis

OBJECTIVES

To discuss the clinical subtypes, pathogenesis, pathology, diagnostic evaluation, treatment options, and prognosis of pulmonary hypertension in systemic sclerosis (SSc-PH) and highlight its fundamental differences from idiopathic pulmonary arterial hypertension (IPAH).

METHODS

A Medline search for articles published between January 1969 and June 2010 was conducted using the following keywords: scleroderma, systemic sclerosis, pulmonary hypertension, pulmonary arterial hypertension, pulmonary veno-occlusive disease, pathogenesis, pathology, investigation, treatment, and prognosis. The essential differences from IPAH in pathogenesis and histopathologic findings were highlighted and the limitations of some of the investigations used were emphasized. The differences in response to currently accepted therapy and prognosis were also reviewed.

RESULTS

In scleroderma, pulmonary hypertension can be present in isolation or along with interstitial lung disease and left heart disease. In SSc-PH, the unique histopathologic findings in the lungs include intimal fibrosis, absence of plexiform lesions, and a high prevalence of pulmonary veno-occlusive disease-like lesions. Both "6-minute walk test" and NT-proBNP have their limitations in the evaluation of SSc-PH. For treatment, calcium channel blockers are ineffective and anticoagulation should be used with caution. Currently approved therapies are not as effective and prognosis is much worse in SSc-PH compared with IPAH.

CONCLUSIONS

SSc-PH is a complex condition with poorer response to therapy and worse outcome compared with that of IPAH. Recent findings have shed some light about the pathophysiology and pathogenesis of SSc-PH. Further research in this area is warranted to better understand the complex pathogenesis and devise better therapeutic strategies.

Imaging lung disease in systemic sclerosis

Interstitial lung disease and pulmonary hypertension (PH) are the most common cardiopulmonary findings in patients with systemic sclerosis (SSc). About two thirds of patients suffering from SSc develop scleroderma interstitial lung disease. PH is present in about 20% of SSc patients and is typically associated with severe lung disease, although it may be an isolated manifestation of SSc. High-resolution CT scanning is a key method for evaluating chest involvement. There are four roles of imaging in scleroderma interstitial lung disease: 1) detection of lung involvement, 2) identification of patients likely to respond to treatment, 3) assessment of treatment efficacy, and 4) exclusion of other significant diseases to include PH and cardiac and esophageal abnormalities.

HLA-B35 upregulates endothelin-1 and downregulates endothelial nitric oxide synthase via endoplasmic reticulum stress response in endothelial cells

The presence of the HLA-B35 allele has emerged as an important risk factor for the development of isolated pulmonary hypertension in patients with scleroderma, however the mechanisms underlying this association have not been fully elucidated. The goal of our study was to determine the molecular mechanisms that mediate the biological effects of HLA-B35 in endothelial cells (ECs). Our data demonstrate that HLA-B35 expression at physiological levels via adenoviral vector resulted in significantly increased endothelin-1 (ET-1) and a significantly decreased endothelial NO synthase (eNOS), mRNA, and protein levels. Furthermore, HLA-B35 greatly upregulated expression of chaperones, including heat shock proteins (HSPs) HSP70 (HSPA1A and HSPA1B) and HSP40 (DNAJB1 and DNAJB9), suggesting that HLA-B35 induces the endoplasmic reticulum (ER) stress and unfolded protein response in ECs. Examination of selected mediators of the unfolded protein response, including H chain binding protein (BiP; GRP78), C/Ebp homologous protein (CHOP; GADD153), endoplasmic reticulum oxidase, and protein disulfide isomerase has revealed a consistent increase of BiP expression levels. Accordingly, thapsigargin, a known ER stress inducer, stimulated ET-1 mRNA and protein levels in ECs. This study suggests that HLA-B35 could contribute to EC dysfunction via ER stress-mediated induction of ET-1 in patients with pulmonary hypertension.

Systemic sclerosis and idiopathic interstitial pneumonia: histomorphometric differences in lung biopsies

OBJECTIVE

The aim of this study was to examine the parenchymal and extracellular matrix remodeling process in two histologic patterns-nonspecific interstitial pneumonia (NSIP) and usual interstitial pneumonia (UIP)-in cases of idiopathic and sclerosis/systemic sclerosis (SSc)-associated interstitial pneumonia.

METHODS

We examined 15 cases of idiopathic NSIP, 10 cases of idiopathic UIP, 5 cases of SSc-UIP and 9 cases of SSc-NSIP. In the lung parenchyma, epithelial cells, endothelial cells and myofibroblasts were evaluated by immunohistochemical staining, whereas histochemical staining was used in order to evaluate collagen/elastic fibers in the extracellular matrix.

RESULTS

The percentage of surfactant protein A-positive epithelial cells was significantly greater in idiopathic NSIP than in SSc-NSIP, as well as being greater in idiopathic UIP than in SSc-UIP. Idiopathic NSIP and idiopathic UIP presented significantly higher immunoexpression of alpha smooth muscle actin in myofibroblasts than did SSc-NSIP and SSc-UIP. The percentage of CD34 endothelial cells in the pulmonary microvasculature was significant lower in idiopathic UIP than in SSc-UIP. The density of collagen fibers was significantly greater in idiopathic NSIP and idiopathic UIP than in SSc-NSIP and UIP. In contrast, the elastic fiber density was significantly lower in idiopathic UIP than in SSc-UIP.

CONCLUSIONS

Increased collagen synthesis, destruction of elastic fibers, high myofibroblast proliferation and poor microvascularization might represent a remodeling process found in idiopathic interstitial pneumonia, whereas the reverse might represent a repair process in SSc-associated interstitial pneumonia.

Biomarkers in systemic sclerosis

Systemic sclerosis is an autoimmune inflammatory disorder of unknown etiologycharacterized b y pronounced fibroproliferative alterations in the microvasculature, and frequent cellular and humoral immunity abnormalities, culminating in a severe and often progressive fibrotic process. Numerous biomarkers reflecting the three main pathogenetic mechanisms in systemic sclerosis have been described; however, aside from several disease-specific autoantibodies, other biomarkers have not been thoroughly validated and require further study. Thus, there is an unmet need for validated biomarkers for diagnosis, disease classification, and evaluation of organ involvement and therapeutic response in systemic sclerosis.

Bosentan: a review of its use in the management of digital ulcers associated with systemic sclerosis

Bosentan (Tracleer) is an orally administered dual endothelin-1 (ET-1) receptor antagonist approved in the EU for reducing the number of new digital ulcers in patients with systemic sclerosis and ongoing digital ulcer disease. Oral bosentan therapy was beneficial and generally well tolerated in patients with digital ulcers associated with systemic sclerosis. In well designed, placebo-controlled trials, bosentan treatment significantly reduced the number of new ulcers, but had no effect on ulcer healing, in patients with digital ulcers. Adverse events associated with bosentan were consistent with those seen during treatment for other indications, with major concerns being the potential for teratogenicity and hepatotoxicity, for which regular liver function monitoring is recommended. Overall, considering the large unmet need for therapeutic options in patients with digital ulcers, bosentan extends the treatment options available to patients with systemic sclerosis-associated digital ulcers.

Role of endogenous endothelin in endothelial dysfunction in murine model of systemic sclerosis: tight skin mice 1

Systemic sclerosis (SSc) is a systemic inflammatory disorder, resulting in severe vascular dysfunction. The endothelin (ET) system has vasoconstrictor and profibrotic properties and has been shown to be activated in SSc. ET antagonists are currently used in SSc-related pulmonary arterial hypertension, but the endothelial impact of ET antagonists remains less known in SSc. We thus assessed the effects of the dual ET(A)-ET(B) antagonist, bosentan, on endothelial dysfunction in a murine model of SSc, the heterozygous tight-skin mice 1 (TSK1(+)). Six-week-old TSK1(+) were either untreated or treated for 6 weeks with bosentan (100 mg/kg/day), and compared with controls. Endothelial function was evaluated in isolated mesenteric resistance arteries, using a small vessel myograph. TSK1(+) displayed endothelial dysfunction, as shown by a decreased response of mesenteric arteries to acetylcholine, especially in the presence of L-nitro-arginine methyl ester (L-NAME), corresponding to NO-independent, prostaglandin-mediated relaxation. The NO-independent relaxation was partially restored in bosentan-treated TSK1(+), and this was abolished by a cyclo-oxygenase inhibitor. Therefore, the murine model of SSc, TSK1(+) exhibits severe endothelial dysfunction of peripheral resistance arteries. The ET antagonist bosentan prevents endothelial alterations, suggesting a major role of ET in the adverse vascular effects of SSc.

The heart in scleroderma

The heart is one of the major organs involved in scleroderma, the involvement of which can be manifested by myocardial disease, conduction system abnormalities, arrhythmias, or pericardial disease. Additionally, scleroderma renal crisis and pulmonary hypertension lead to significant cardiac dysfunction secondary to damage in the kidney and lung. This article summarizes the types and mechanism of abnormalities in the heart in scleroderma. The concept of cardiac dysfunction in scleroderma and other rheumatologic conditions has received new interest with the advent of newer noninvasive imaging techniques, as well as the interest in detecting subclinical disease. With this increased interest in cardiac manifestations in scleroderma comes the realization that long-term studies are needed to better assess the appropriate screening and treatment in this patient population.

Autopsy case of systemic sclerosis with severe pulmonary hypertension

We report an autopsy case of a 60-year-old Japanese woman who died 27 years after the onset of systemic sclerosis and 4 years after the diagnosis of pulmonary arterial hypertension. Oral administration of bosentan was effective in improving her dyspnea but had to be stopped because of drug eruption along with fever and eosinophilia. During hospitalization for the treatment of multiple skin ulcers and gangrene, she suddenly complained of severe respiratory difficulty, followed by bradycardia, unconsciousness and cardiopulmonary arrest. The autopsy revealed concentric intimal proliferation and marked luminal obstruction in many small- and medium-sized vessels of the lungs. In addition to right ventricular hypertrophy and dilatation, similar vascular changes were also present in the myocardial tissue and the atrioventricular node. In our patient, these marked vascular changes caused pulmonary hypertension followed by the severe right heart failure. The vascular changes in the atrioventricular node were suspected as the cause of a fatal arrhythmia leading to sudden death.

Comprehensive investigation of disease-specific short peptides in sera from patients with systemic sclerosis: complement C3f-des-arginine, detected predominantly in systemic sclerosis sera, enhances proliferation of vascular endothelial cells

OBJECTIVE

To identify pathogenic and/or disease-specific short peptides in sera from patients with systemic sclerosis (SSc).

METHODS

Serum samples from 40 patients with SSc, 30 patients with systemic lupus erythematosus, 21 patients with rheumatoid arthritis, 30 patients with osteoarthritis, and 26 healthy donors were tested. Short peptides with molecular weights of smaller than approximately 3 kd, purified from the sera by magnetic bead-based hydrophobic interaction chromatography 18, were detected and their amino acid sequences determined using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry. Effects of the identified peptides on fibroblasts and microvascular endothelial cells were tested using synthesized peptides and sera containing the peptides.

RESULTS

A group of peptides with mass/charge (m/z) values of 1,865, 1,778, 1,691, 1,563, and 1,450 were detected predominantly in the SSc sera. These peptides were identified as family members of complement C3f-des-arginine (DRC3f) derived from C3b. The level of DRC3f (m/z 1,865) was related to vascular involvement in SSc and to SSc disease activity. The synthesized peptides of DRC3f and C3f, as well as the filtrated sera containing DRC3f, enhanced proliferation of microvascular endothelial cells, but not fibroblasts. Both DRC3f and C3f increased production of transforming growth factor beta1 by dermal microvascular endothelial cells.

CONCLUSION

This comprehensive peptidomics analysis revealed the predominance of DRC3f in the sera of patients with SSc. Investigation of DRC3f may be a useful tool for the diagnosis and evaluation of disease activity in SSc. Moreover, its demonstrated effects on endothelial cells suggest a potential role for DRC3f in the pathophysiologic mechanisms of SSc.

Measuring Outcomes in PAH: The Gap between the Measures That Are Used and Their Validity

Pulmonary arterial hypertension (PAH) has poor prognosis in systemic sclerosis (SSc), and at present the "gold standard" for diagnosis and follow-up of PAH in SSc is right heart catheterization (RHC) but it would be very useful to have a noninvasive way to follow these patients. Using the OMERACT criteria for validation of measures of response, the only fully validated measure for PAH in SSc has been the 6-min walking test. Multiple other measures are particularly valid (e.g., echocardiography, brain natriuretic protein [BNP], FV/DLCO) while a few are unlikely ever to be validated for various reasons (e.g., symptoms, MRA). A Delphi exercise among 78 experts (EPOSS) has been done and has developed a consensus document consisting of eight domains (lung vascular/PAP, exercise capacity, cardiac function, dyspnea, discontinuation of treatment, quality of life, lung parenchymal, and global state), which can be used and must be tested.

Fibrous remodeling of the pulmonary venous system in pulmonary arterial hypertension associated with connective tissue diseases

Pulmonary arterial hypertension is a severe complication of connective tissue diseases. It is currently well established that pulmonary arterial hypertension associated with connective tissue diseases such as systemic sclerosis is frequently less responsive or even refractory to pulmonary vasodilator therapies. In that setting, pulmonary venoocclusive disease is believed to contribute to treatment failures. We therefore hypothesized that pulmonary arterial hypertension associated with connective tissue diseases may be associated with obstructive lesions of pulmonary veins. Lung samples from 8 patients with pulmonary arterial hypertension associated with connective tissue disease (4 limited systemic sclerosis, 2 systemic lupus erythematosus, 1 mixed connective tissue diseases, and 1 rheumatoid arthritis) were studied by light microscopy and analyzed by immunohistochemistry (5 postmortem samples, 3 explants after lung transplantation). Findings were compared with 29 pulmonary arterial hypertension cases from patients displaying neither connective tissue diseases nor associated conditions. We found that (a) 6 (75%) of 8 patients with pulmonary arterial hypertension associated with connective tissue diseases showed significant obstructive pulmonary vascular lesions predominating in veins/preseptal venules, as compared with 5 (17.2%) of 29 non-connective tissue diseases control pulmonary arterial hypertension; (b) lesions of small muscular arteries were consistently present in pulmonary arterial hypertension associated with connective tissue diseases, showing mostly intimal fibrosis and thrombotic lesions; and (c) 6 of 8 lung samples from patients with pulmonary arterial hypertension associated with connective tissue diseases revealed perivascular inflammatory infiltration. In conclusion, our study highlights the fact that pulmonary arterial hypertension complicating the course of connective tissue diseases may be characterized by a more frequent involvement of pulmonary veins and may thus explain why these patients are less prone to respond to specific pulmonary arterial hypertension treatment as compared with idiopathic pulmonary arterial hypertension.

Vascular complications of scleroderma

Systemic sclerosis (SSc) is a multiorgan disease characterized by injury to vascular wall and extensive damage of the microvessels. The injury of the vascular wall is characterized by the formation of megacapillaries and avascular areas. The reduced capillary density leads to clinical manifestations such as digital ulcers. These lesions are extremely painful and lead to substantial functional disability. Management of digital ulcers includes non-pharmacologic and pharmacologic modalities. Despite the reduced blood flow and reduced partial oxygen pressure levels, there is paradoxically no evidence for a sufficient angiogenesis in the skin of patients with SSc. Angiogenesis is strongly disturbed in SSc, as demonstrated by Nailfold Video-Capillaroscopy changes, the damage of the vessels evolves progressively from early to late stages and is characterized by different morphological aspects. Almost all patients develop Raynaud's phenomenon which, together with structural vasculopathy, results in ulceration and critical digital ischemia. Many of the severe internal organ complications of SSc are vascular, including pulmonary arterial hypertension (PAH) and scleroderma renal crisis. Structural vascular damage occurs in many vascular beds and contribute to pulmonary, renal, cardiac and gastrointestinal complications. SSc has a high case-specific mortality due to organ-based complications including PAH, lung fibrosis, renal failure and involvement of the gastrointestinal tract.

A clue for telangiectasis in systemic sclerosis: elevated serum soluble endoglin levels in patients with the limited cutaneous form of the disease

BACKGROUND

The transforming growth factor-beta (TGF-beta) system plays a critical role both in systemic sclerosis (SSc) and hereditary hemorrhagic telangiectasia (HHT). Endoglin, known as a gene responsible for HHT, is a TGF-beta receptor preferentially expressed on endothelial cells. The role of endoglin in SSc is potentially intriguing since limited cutaneous SSc (lcSSc) and HHT share several symptoms, including telangiectasia.

OBJECTIVE

To determine serum levels of soluble endoglin (sEndoglin) and clinical associations in patients with SSc.

METHODS

Serum sEndoglin levels were examined by ELISA in 70 patients with SSc, 20 patients with systemic lupus erythematosus and 20 healthy individuals.

RESULTS

Serum sEndoglin levels were significantly elevated in patients with lcSSc compared with diffuse cutaneous SSc and systemic lupus erythematosus patients as well as normal controls. Patients with elevated sEndoglin levels had telangiectasia more frequently than those with normal sEndoglin levels. Furthermore, pulmonary artery pressure was positively correlated with sEndoglin levels in patients with lcSSc.

CONCLUSION

Abnormal expression/function of endoglin may be linked to lcSSc-specific manifestations.

HLA-B35 upregulates the production of endothelin-1 in HLA-transfected cells: a possible pathogenetic role in pulmonary hypertension

HLA-B35 is associated with an increased risk for developing isolated pulmonary hypertension (iPHT) in systemic sclerosis, but the mechanisms underlying this association have not been fully elucidated yet. Endothelin-1 (ET-1) is the main pathogenetic molecule implied in the development of iPHT; therefore, we sought to determine if ECV304 cells transfected with the HLA-B35 allele produce increased amounts of ET-1 after incubation with physiological concentrations of interleukin-1 beta (IL-1beta). ECV304 cells transfected with HLA-B*3501 and HLA-B*0801 polymorphic alpha chain or with pIRESneo2 were incubated with 100 U/ml of IL-1beta for 6, 12, 24, 36 and 48 h. ET-1 levels were determined using EIA kit (CAYMAN Chemical, Ann Arbor, MI) in supernatants from different cell cultures; the relative expression of the preproendothelin-1 (PPET-1) gene was also determined by reverse transcription-polymerase chain reaction. Cells expressing the HLA-B35 allele showed significantly increased levels of ET-1 at all the selected times compared with controls or HLA-B8-transfected cells. The relative expression of the PPET-1 gene was also increased in a proportionally direct manner. The HLA-B35 allele influences the production of ET-1 in HLA-B35-transfected ECV304 cells by promoting the expression of its precursor, PPET-1. Our results provide an explanation for the epidemiological association existing between iPHT and HLA-B35.

[Pulmonary involvement in systemic sclerosis. Alveolitis, fibrosis and pulmonar arterial hypertension]

Pulmonary involvement in systemic sclerosis. Alveolitis, fibrosis and pulmonar arterial hypertension Lung disease is present in most of the patients with systemic sclerosis and is now the most important cause of mortality. Interstitial lung disease and pulmonary hypertension are, so far, the main disorders found and both are difficult to detect at the earliest stages. However, diagnostic tools such as immunological test, lung function test, high resolution CT, bronchoalveolar lavage, echocardiography, right-side cardiac catheterization, or lung biopsy are necessary to accurately evaluate the clinical status and allow to improve the management organ-specific ad hoc. Progress in immunological and vascular therapies as well as other emergence drugs offer new expectations to scleroderma patients.

Bosentan for severe pulmonary arterial hypertension related to systemic sclerosis with interstitial lung disease

BACKGROUND

The oral dual endothelin (ET) antagonist bosentan has been established as a cornerstone in the treatment of pulmonary arterial hypertension (PAH). ET is believed to be a key pathogenic mediator in systemic sclerosis (scleroderma, SSc), causing fibrotic, hypertrophic and inflammatory processes. PAH is one of the resulting deleterious effects in approximately 15% of SSc patients.

MATERIALS AND METHODS

This was an open-label prospective observational study of 8 patients aged 34-73 years with symptomatic, severe PAH related to SSc (WHO class III or IV) and mostly, lung fibrosis. PAH diagnosis was ascertained with echocardiography or right heart catheterization. Patients were treated on top of diuretics and anticoagulants with bosentan 62.5 mg twice daily for 4 weeks followed by a maintenance dose of 125 mg twice daily.

RESULTS

The mean 6-minute walk distance (data available in 7 patients) increased from 71.9 (+/- 54.7) m at baseline to 191.9 (+/- 104.6) m after 3 months (P = 0.012) and to 202.6 (+/- 108.1) m after 6 months (P = 0.011), respectively. Six of 8 patients improved in the 6-minute walk test, and these 6 patients also improved in World Health Organization functional class. Two patients did not sufficiently respond to bosentan therapy; one of them died. The tolerability of bosentan was good, and there were no discontinuations. Elevations of hepatic aminotransferases above 3 times the upper limit of normal were not recorded.

CONCLUSION

Bosentan treatment was well tolerated in this cohort of SSc patients with interstitial lung disease and was effective for treatment of severe PAH in the majority of patients.

Drug eruption due to bosentan in a patient with systemic sclerosis

We present the case of a 60-year-old female patient with systemic sclerosis complicated by pulmonary hypertension. Ten days after the initiation of treatment with bosentan, high fever and skin eruptions were noted. In the previous reports, the frequency of drug-induced skin eruptions has not been well documented. Since the use of bosentan is expected to increase, we should be aware of the previously unknown adverse effects as well as skin eruptions.