Systemic sclerosis (scleroderma) is characterized by immunologic abnormalities, injury of endothelial cells, and tissue fibrosis. Abnormal oxidative stress has been documented in scleroderma and ...linked to fibroblast activation. Since platelet-derived growth factor (PDGF) stimulates the production of reactive oxygen species (ROS) and since IgG from patients with scleroderma reacts with human fibroblasts, we tested the hypothesis that patients with scleroderma have serum autoantibodies that stimulate the PDGF receptor (PDGFR), activating collagen-gene expression.
We analyzed serum from 46 patients with scleroderma and 75 controls, including patients with other autoimmune diseases, for stimulatory autoantibodies to PDGFR by measuring the production of ROS produced by the incubation of purified IgG with mouse-embryo fibroblasts carrying inactive copies of PDGFR alpha or beta chains or the same cells expressing PDGFR alpha or beta. Generation of ROS was assayed with and without specific PDGFR inhibitors. Antibodies were characterized by immunoprecipitation, immunoblotting, and absorption experiments.
Stimulatory antibodies to the PDGFR were found in all the patients with scleroderma. The antibodies recognized native PDGFR, inducing tyrosine phosphorylation and ROS accumulation. Autoantibody activity was abolished by preincubation with cells expressing the PDGFR alpha chain or with recombinant PDGFR or by PDGFR tyrosine kinase inhibitors. Stimulatory PDGFR antibodies selectively induced the Ha-Ras-ERK1/2 and ROS cascades and stimulated type I collagen-gene expression and myofibroblast phenotype conversion in normal human primary fibroblasts.
Stimulatory autoantibodies against PDGFR appear to be a specific hallmark of scleroderma. Their biologic activity on fibroblasts strongly suggests that they have a causal role in the pathogenesis of the disease.
To evaluate, in a pilot study, the efficacy of a short term cyclophosphamide (CYC) pulse regimen on alveolitis in a cohort of patients with systemic sclerosis (SSc).
Twenty-three patients with SSc ...(17 diffuse SSc and 6 limited SSc) were selected in 5 centers in Italy, based on the findings of an abnormal bronchoalveolar lavage (BAL) cell analysis in association with altered pulmonary function tests (PFT) or recent deterioration in flow volume curve (FVC). Patients were also evaluated by skin score (Rodnan), esophageal manometry and barium swallow radiography, and electrocardiography and 2-mode echocardiography. The pre-enrolment pulmonary evaluation and after 6 months of therapy included evaluation of the clinical status, PFT (FVC, FEV1, DLCO), BAL. standard chest radiograph, and chest high resolution computed tomography. All patients received i.v. CYC (1000 mg/m2 of body surface monthly for 6 mo) and oral prednisone (25 mg daily for the first month and subsequently 5 mg daily of maintenance dosage for the remaining 5 mo). A complete blood count and urinalysis were obtained at monthly intervals.
After 6 months of therapy the values for FVC did not change significantly. Individually, 8 of 23 patients showed an improvement (> 15% increase) in FVC after 6 months, while FVC in 13 cases remained stable. Only 2 patients had an important decline in FVC after 6 months of therapy (17 and 24% decrease). Improvement in DLCO was noted in 15 of 23 patients after 6 months of therapy. Four patients were stable and 4 patients had a worsened DLCO at the end of the study. After therapy the mean value of BAL fluid recovery did not change. There was a reduction in total cell number although this value did not reach statistical significance. The levels of neutrophils, eosinophils, lymphocytes, and macrophages did not change significantly. Scans for patients with grades 1, 2, and 3 did not differ significantly after 6 months of therapy, and 14 patients were stable. Changes in appearance, in relation to changes in extent of disease, were seen in 8 patients and consisted of an extension of reticular pattern and transformation from grade 1 to 2 (6/8 patients). All patients showed a ground-glass appearance indicating an acute alveolitis. Improvement in ground-glass was noted in 10 of 23 patients after 6 mo therapy. At the end of the study, 8 patients were stable and 5 patients had a diffusion of the ground-glass to other segments. No side effects were experienced during the treatment except for mild nausea in 4 patients; no patients discontinued therapy during the study.
CYC pulse regimen seems to stabilize alveolitis in the majority of cases. The association of CYC pulsed modality with prednisone may be useful in SSc patients to control disease evolution in the lung.
The levels of Ras proteins in human primary fibroblasts are regulated by PDGF (platelet-derived growth factor). PDGF induced post-transcriptionally Ha-Ras by stimulating reactive oxygen species (ROS) ...and ERK1/2. Activation of ERK1/2 and high ROS levels stabilize Ha-Ras protein, by inhibiting proteasomal degradation. We found a remarkable example in vivo of amplification of this circuitry in fibroblasts derived from systemic sclerosis (scleroderma) lesions, producing vast excess of ROS and undergoing rapid senescence. High ROS, Ha-Ras, and active ERK1/2 stimulated collagen synthesis, DNA damage, and accelerated senescence. Conversely ROS or Ras inhibition interrupted the signaling cascade and restored the normal phenotype. We conclude that in primary fibroblasts stabilization of Ras protein by ROS and ERK1/2 amplifies the response of the cells to growth factors and in systemic sclerosis represents a critical factor in the onset and progression of the disease.
Iloprost is recommend worldwide for the treatment of RP and the healing of DUs. The aim of this study is to report the regimens of Iloprost administered in different rheumatological centers within ...the same regional Health System Methods: A questionnaire exploring different items related to the use of Iloprost was developed and reviewed by three expert rheumatologists. The questionnaire was distributed as an online survey to all local SSc referral centers in Emilia-Romagna (Italy). Data are reported as percentage or median with interquartile range (IQR), as appropriate. An updated review of world literature on this topic was also carried out.
All the invited centers completed the survey. There were both local (8) and university hospitals (4). The majority (58%) had a rheumatologist as head physician. All centers used Iloprost: a single monthly administration was the most common treatment (75%). The cycle lasted 1 IQR 1-2 days with a 0.5-2.0 ng/Kg/min dose according to the drug tolerance of the patients. There were overall 68 spots (beds, reclining armchair, or simple armchair); 2.0 1.5-4.0 patients were able to receive Iloprost at the same time. University Hospitals had more physicians at their disposal than local hospitals but less paramedic personnel (respectively: 1.8 vs 1.2 physicians, 1.5 vs 2.1 nurses).
These observations were in line with the majority of previous studies reporting different regimens, comparing similar (but not identical) dose and schedule administration, however, despite differences being at times substantial, no standard infusion method is yet available.
The levels of Ras proteins in human primary fibroblasts are regulated by PDGF (platelet-derived growth factor). PDGF induced post-transcriptionally Ha-Ras by stimulating reactive oxygen species (ROS) ...and ERK1/2. Activation of ERK1/2 and high ROS levels stabilize Ha-Ras protein, by inhibiting proteasomal degradation. We found a remarkable example in vivo of amplification of this circuitry in fibroblasts derived from systemic sclerosis (scleroderma) lesions, producing vast excess of ROS and undergoing rapid senescence. High ROS, Ha-Ras, and active ERK1/2 stimulated collagen synthesis, DNA damage, and accelerated senescence. Conversely ROS or Ras inhibition interrupted the signaling cascade and restored the normal phenotype. We conclude that in primary fibroblasts stabilization of Ras protein by ROS and ERK1/2 amplifies the response of the cells to growth factors and in systemic sclerosis represents a critical factor in the onset and progression of the disease.
To perform a population-based study in rheumatoid arthritis (RA) patients, in order to evaluate the efficacy and safety of pharmacologic treatments.
1087 patients with RA were enrolled; inclusion ...criteria were: newly diagnosed RA, already diagnosed RA with high disease activity (HDA) (DAS28≥4.2) starting biologic DMARDs (bDMARDs), already diagnosed RA with HDA continuing with conventional DMARDs (cDMARDs). The following data were collected: demographics, clinical and laboratory features, imaging and prescribed drugs. All parameters except immunology and imaging (performed yearly) were repeated at each follow-up evaluations (after 3, 6 and 12 months, and thereafter every 12 months). In order to evaluate clinical response, the EULAR response criteria were used as the gold standard.
414 (38.1%) newly diagnosed patients with RA, 477 (43.9%) RA patients who started bDMARDs and 196 (18.0%) RA patients who continued with cDMARDs were enrolled from April 2012 to March 2015 at 12 Rheumatology Centres in the Emilia Romagna Region. Statistical analyses showed a relative risk ratio (RRR) for moderate response of 1.65 in RA patients who started bDMARDs (p=0.16) and 2.49 for newly diagnosed RA (p=0.01). Sex, age and Health Assessment Questionnaire were not statistically significant. A RRR of 2.00 has been confirmed for RA patients who started bDMARDs (p<0.0005) for a good response as well as 2.20 for newly diagnosed RA (p<0.0005). An increase in adverse events among bDMARDs was found, but when looking at infections or neoplasia, no differences were highlighted between RA which started bDMARDs and RA who continued with cDMARDs.
Our results are in line with already published papers from British and Swedish Registries: a greater likelihood to have a good response is demonstrated for not longstanding RA starting cDMARDs or RA with HDA when a bDMARD is started. Also a good safety profile is demonstrated.
Acid-suppressive therapy (AST) is largely prescribed in both hospital and general practice setting but few data are available on appropriateness of AST use in hospitalized patients and its fallout on ...prescribing in general practice. We assessed AST in patients consecutively admitted to an internal medicine department to determine the type and timing of prescription and indication for use according to widely accepted guidelines. Prescriptions were rated as indicated, acceptable, or not indicated. Overall, 58.7% of 834 admitted patients received AST, mainly proton pump inhibitors. The prescriptions were indicated in 50.1% of patients, not indicated in 41.5%, and acceptable in 6.5%. The main reason for inappropriate use was prophylaxis in low-risk patients (64.8%). On admission, 35.7% of 112 patients already on AST were judged to receive inappropriate prescription; of 348 patients discharged on AST, overuse was identified in 38.5%. No significant difference was observed for inappropriate use at admission, during hospitalization, and at discharge. In 64 inpatients (7.7%) AST, although indicated, mainly for ulcer prophylaxis in high-risk patients, was not prescribed. In conclusion, AST is substantially over-used in both hospital and general practice settings, mainly for ulcer prophylaxis in low-risk patients. On the other hand, AST is underused in a small, but not negligible proportion of high-risk patients.
Objective
To explore the role of reactive oxygen species (ROS) in the in vitro activation of skin fibroblasts from patients with systemic sclerosis (SSc).
Methods
Fibroblasts were obtained from ...involved skin of patients with limited or diffuse SSc. Oxidative activity imaging in living cells was carried out using confocal microscopy. Levels of O2− and H2O2 released from fibroblasts were estimated by the superoxide dismutase (SOD)–inhibitable cytochrome c reduction and homovanilic acid assays, respectively. To verify NADPH oxidase activation, the light membrane of fibroblasts was immunoblotted with an anti‐p47phox–specific antibody. Fibroblasts were stimulated with various cytokines and growth factors to determine whether any of these factors modulate ROS generation. Cell proliferation was estimated by 3H‐thymidine incorporation. Northern blot analysis was used to study α1 and α2 type I collagen gene expression.
Results
Unstimulated skin fibroblasts from SSc patients released more O2− and H2O2 in vitro through the NADPH oxidase complex pathway than did normal fibroblasts, since incubation of SSc fibroblasts with diphenylene iodonium, a flavoprotein inhibitor, suppressed the generation of ROS. This suppression was not seen with rotenone, a mitochondrial oxidase inhibitor, or allopurinol, a xanthine oxidase inhibitor. Furthermore, the cytosolic component of NADPH oxidase, p47phox, was translocated to the plasma membrane of resting SSc fibroblasts. A transient increase in ROS production was induced in normal but not in SSc fibroblasts by interleukin‐1β (IL‐1β), platelet‐derived growth factor type BB (PDGF‐BB), transforming growth factor β1 (TGFβ1), and H2O2. Treatment of normal and SSc fibroblasts with tumor necrosis factor α (TNFα), IL‐2, IL‐4, IL‐6, IL‐10, interferon‐α (IFNα), IFNγ, granulocyte–macrophage colony‐stimulating factor (GM‐CSP), G‐CSF, or connective tissue growth factor (CTGF) had no effect on ROS generation. Constitutive ROS production by SSc fibroblasts was not inhibited when these cells were treated with catalase, SOD, IL‐1 receptor antagonist, or antibodies blocking the effect of TGFβ1, PDGF‐BB, and other agonists (IL‐4, IL‐6, TNFα, CTGF). In contrast, treatment of SSc fibroblasts with the membrane‐permeant antioxidant N‐acetyl‐L‐cysteine inhibited ROS production, and this was accompanied by decreased proliferation of these cells and down‐regulation of α1(I) and α2(I) collagen messenger RNA.
Conclusion
The constitutive intracellular production of ROS by SSc fibroblasts derives from the activation of an NADPH oxidase–like system and is essential to fibroblast proliferation and expression of type I collagen genes in SSc cells. Our results also exclude O2−, H2O2, IL‐1β, TGFβ1, PDGF‐BB, IL‐4, IL‐6, TNFα, or CTGF as mediators of a positive, autocrine feedback mechanism of ROS generation.
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