Autoantibody against caspase-3, an executioner of apoptosis, in patients with systemic sclerosis

Anti-inflammatory and antioxidative effects of elderberry diet in the rat model of seizure: a behavioral and histological investigation on the hippocampus

The present study was designed to evaluate whether elderberry (EB) effectively reduces inflammation and oxidative stress in hippocampal cells to modify seizure damage. Seizure was induced in rats by the injection of pentylenetetrazol (PTZ). In the Seizure + EB group, EB powder was added to the rats' routine diet for eight consecutive weeks. The study included several behavioral tests, immunohistopathology, Voronoi tessellation (to estimate the spatial distribution of cells in the hippocampus), and Sholl analysis. The results in the Seizure + EB group showed an improvement in the behavioral aspects of the study, a reduction in astrogliosis, astrocyte process length, number of branches, and intersections distal to the soma in the hippocampus of rats compared to controls. Further analysis showed that EB diet increased nuclear factor-like 2 expression and decreased caspase-3 expression in the hippocampus in the Seizure + EB group. In addition, EB protected hippocampal pyramidal neurons from PTZ toxicity and improved the spatial distribution of hippocampal neurons in the pyramidal layer and dentate gyrus. The results of the present study suggest that EB can be considered a potent modifier of astrocyte reactivation and inflammatory responses.

A comparative study of modulatory interaction between cytokines and apoptotic proteins among Scleroderma patients with and without pulmonary involvement

BACKGROUND

Interstitial lung disease (ILD) and pulmonary arterial hypertension (PAH) are the most eminent forms of pulmonary involvement in Scleroderma. In this study we investigate the interaction between cytokines and apoptotic proteins in treatment naive Scleroderma (SSc) patients with and without pulmonary involvement.

METHODS

Newly diagnosed treatment naïve Scleroderma (SSc) patients (n = 100) and healthy controls (n = 100) were enrolled. Patients were classified as ILD-SSc, PAH-SSc and non-pulmonary SSc (np-SSc). Study variables like mRSS score, autoantibody profile, serum cytokines, serum TGF-β (1,2,3) and apoptotic proteins were assessed for these patients.

RESULTS

Scleroderma patients showed elevated levels of serum cytokines, but significantly lower IL-22 and TGF- β1 when compared to healthy controls (p < 0.05). Apoptotic proteins were significantly elevated among Scleroderma patients, but the patient groups also showed significant lower caspase 1/3/9 levels when compared to healthy controls (p < 0.05). ILD-SSc patients reported higher mRSS score (p = 0.0436) when compared with PAH-SSc and np-SSc. In ILD-SSc patients, finger tightening (p = 0.0481) and calcinosis/lesions (p = 0.0481) were significant clinical presentations whereas, digital ulcers were significantly prominent in np-SSc patients (p = 0.0132). Elevated TGF-β3 levels (p = 0.02) in SSC-ILD and reduced IL-4 levels (p = 0.02) in SSC-PAH were significant cytokines as compared to np-SSc. Significant correlations were obtained among serum cytokines and apoptotic proteins in Scleroderma patients with and without pulmonary involvement. (p < 0.05) CONCLUSION: Our study highlights the correlation between mRSS score, cytokines and apoptotic proteins in SSc patients with pulmonary involvement. A longitudinal follow up in these patients with assessment of these immunological parameters may be helpful in monitoring the disease.

The role of endothelial cells in the vasculopathy of systemic sclerosis: A systematic review

INTRODUCTION

Systemic sclerosis (SSc) is an autoimmune connective tissue disorder characterized by fibroproliferative vasculopathy, immunological abnormalities and progressive fibrosis of multiple organs including the skin. In this study, all English speaking articles concerning the role of endothelial cells (ECs) in SSc vasculopathy and representing biomarkers are systematically reviewed and categorized according to endothelial cell (EC) (dys)function in SSc.

METHODS

A sensitive search on behalf of the EULAR study group on microcirculation in Rheumatic Diseases was developed in Pubmed, The Cochrane Library and Web of Science to identify articles on SSc vasculopathy and the role of ECs using the following Mesh terms: (systemic sclerosis OR scleroderma) AND pathogenesis AND (endothelial cells OR marker). All selected papers were read and discussed by two independent reviewers. The selection process was based on title, abstract and full text level. Additionally, both reviewers further searched the reference lists of the articles selected for reading on full text level for supplementary papers. These additional articles went through the same selection process.

RESULTS

In total 193 resulting articles were selected and the identified biomarkers were categorized according to description of EC (dys)function in SSc. The most representing and reliable biomarkers described by the selected articles were adhesion molecules for EC activation, anti-endothelial cell antibodies for EC apoptosis, vascular endothelial growth factor (VEGF), its receptor VEGFR-2 and endostatin for disturbed angiogenesis, endothelial progenitors cells for defective vasculogenesis, endothelin-1 for disturbed vascular tone control, Von Willebrand factor for coagulopathy and interleukin (IL)-33 for EC-immune system communication. Emerging, relatively new discovered biomarkers described in the selected articles, are VEGF₁₆₅b, IL-17A and the adipocytokines. Finally, myofibroblasts involved in tissue fibrosis in SSc can derive from ECs or epithelial cells through a process known as endothelial-to-mesenchymal transition.

CONCLUSION

This systematic review emphasizes the growing evidence that SSc is primarily a vascular disease where EC dysfunction is present and prominent in different aspects of cell survival (activation and apoptosis), angiogenesis and vasculogenesis and where disturbed interactions between ECs and various other cells contribute to SSc vasculopathy.

D1398G Variant of MET Is Associated with Impaired Signaling of Hepatocyte Growth Factor in Alveolar Epithelial Cells and Lung Fibroblasts

Pulmonary fibrosis represents the terminal stage of a diverse group of lung diseases including scleroderma associated interstitial lung disease. The molecular mechanisms underlying the pathogenesis of lung fibrosis are not well understood and there is a great need for more effective treatment for this lethal disease. We recently discovered a small fragment of hepatocyte growth factor (HGF) receptor MET as a peptide designated “M10,” with strong antifibrotic properties. Furthermore, we showed that aspartic acid at position 1398 of MET is essential for M10 generation. The current study was undertaken to investigate the D1398G variant of MET in which aspartic acid at position 1398 was mutated to glycine resulting in loss of M10. We demonstrate that lung fibroblasts, A549, and primary alveolar epithelial cells (AEC) expressing D1398G MET exhibit reduced auto-phosphorylation on tyrosine residues and reduced activation of Ras and MAPK. HGF treatment of scleroderma lung fibroblasts as well as HGF treatment of TGFβ-treated normal lung fibroblasts transfected with wild type MET is associated with decreased collagen, connective tissue growth factor (CTGF, CCN2) and smooth muscle α-actin (SMA). However, HGF has no such effects in cells transfected with MET D1398G. Cisplatin- and FasL-induced apoptosis is significantly reduced in AEC transfected with MET wild type, but not in AEC transfected with MET D1398G. We conclude that the D1398G variant of MET is associated with compromised phosphorylation and impaired HGF signaling in lung fibroblasts and AEC, two cell types implicated in the pathogenesis of pulmonary fibrosis associated with scleroderma. Ongoing studies will explore the frequency of this variant and its relationship to pulmonary outcomes in scleroderma patients.

M10, a caspase cleavage product of the hepatocyte growth factor receptor, interacts with Smad2 and demonstrates antifibrotic properties in vitro and in vivo

Hepatocyte growth factor receptor, also known as cellular mesenchymal-epithelial transition factor (c-MET, MET), is an important antifibrotic molecule that protects various tissues, including lung, from injury and fibrosis. The intracellular cytoplasmic tail of MET contains a caspase-3 recognition motif "DEVD-T" that on cleavage by caspase-3 generates a 10-amino acid peptide, TRPASFWETS, designated as "M10". M10 contains at its N-terminus the uncharged amino acid proline (P) directly after a cationic amino acid arginine (R) which favors the transport of the peptide through membranes. M10, when added to cell culture medium, remains in the cytoplasm and nuclei of cells for up to 24 hours. M10 effectively decreases collagen in both scleroderma and TGFβ-stimulated normal lung and skin fibroblasts. M10 interacts with the Mad Homology 2 domain of Smad2 and inhibits TGFβ-induced Smad2 phosphorylation, suggesting that the antifibrotic effects of M10 are mediated in part by counteracting Smad-dependent fibrogenic pathways. In the bleomycin murine model of pulmonary fibrosis, M10 noticeably reduced lung inflammation and fibrosis. Ashcroft fibrosis scores and lung collagen content were significantly lower in bleomycin-treated mice receiving M10 as compared with bleomycin-treated mice receiving scrambled peptide. We conclude that M10 peptide interacts with Smad2 and demonstrates strong antifibrotic effects in vitro and in vivo in an animal model of lung fibrosis and should be considered as a potential therapeutic agent for systemic sclerosis and other fibrosing diseases.

Cytokines in the immunopathology of systemic sclerosis

Cytokines and growth factors are key regulators of immune activation, vascular alteration and excessive production of extracellular matrix which are hallmark events in the pathogenesis of systemic sclerosis (SSc). They modulate cell-cell and cell-matrix interactions. In particular, cytokines play a central role in the immunopathogenesis of SSc on the basis of molecular pathways which are complex and not completely understood. The majority of cytokines that may be involved in SSc pathogenesis have effect upon or are derived from cells of the immune system, including both the innate and adaptive compartments. Novel therapies that block key mediators that drive the fibrotic response are being developed and appear as potential therapeutic tools in the treatment of SSc, highlighting the importance for an effective therapy targeted towards the molecular and cellular pathways. This article reviews cytokine biology in that context, with particular emphasis on immunopathology of the disease, therapeutic targeting and the way that current or emerging treatments for SSc might impact on cytokine biology.

Autoantibody Against Survivin in Patients with Systemic Sclerosis

Objective.

In patients with systemic sclerosis (SSc), to determine concentrations of antibodies against survivin and their clinical association with SSc, and to evaluate serum survivin concentrations.

Methods.

Anti-survivin antibody was examined by ELISA and immunoblotting using human recombinant survivin. Serum survivin levels were assessed by ELISA.

Results.

IgG but not IgM anti-survivin antibody levels in patients with SSc were significantly higher than those in healthy controls and patients with systemic lupus erythematosus (SLE). When cutoff values were set as mean + 2 SD of control, IgG anti-survivin antibodies were positive in 41% (25/61) of patients with SSc, while they were detected in only 1 healthy individual (3%, 1/29) and 1 patient with SLE (5%, 1/20). Regarding the clinical correlation, patients with SSc who were positive for IgG anti-survivin antibody exhibited significantly longer disease duration than those who were negative. Immunoblotting analysis confirmed the presence of anti-survivin antibody in sera from patients with SSc. Serum survivin levels in patients with SSc were also significantly higher than in controls and patients with SLE.

Conclusion.

Our results suggest that autoantibody against survivin is generated in patients with SSc, especially those with long disease duration.