New cytokines in the pathogenesis of rheumatic diseases

Background: An imbalance between pro- and anti- inflammatory cytokine activities favors the induction of autoimmunity, chronic inflammation and joint damage in patients with rheumatoid arthritis (RA). Adipokines are bioactive proteins that are important regulators of inflammation. IL-35 is a new cytokine involved in the inflammatory processes in mouse models and is of unknown function in humans. The aim of the work was to study the levels and role of several adipokines and IL-35 in the joint and blood compartment and the association with the disease activity in patients with RA or other rheumatic diseases. Results: We found increased levels of adiponectin in serum of patients with erosive osteoarthritis (OA) of the hand, differential regulation of new adipokines vaspin and omentin in synovial fluid of patients with RA compared with OA and the effect of therapy using TNFα inhibitor on the expression profile of adipokines in subcutaneous adipose tissue of RA patients. B cell depletion therapy in RA resulted in decrease of serum levels of visfatin that correlated with following change of disease activity. The levels of IL-35 in synovial fluid are significantly higher in RA than in OA and correlate with the disease activity and functional status. IL-35 subunits p35 and EBI3 are overexpressed in RA..

New cytokines in the pathogenesis of rheumatic diseases

Background: An imbalance between pro- and anti- inflammatory cytokine activities favors the induction of autoimmunity, chronic inflammation and joint damage in patients with rheumatoid arthritis (RA). Adipokines are bioactive proteins that are important regulators of inflammation. IL-35 is a new cytokine involved in the inflammatory processes in mouse models and is of unknown function in humans. The aim of the work was to study the levels and role of several adipokines and IL-35 in the joint and blood compartment and the association with the disease activity in patients with RA or other rheumatic diseases. Results: We found increased levels of adiponectin in serum of patients with erosive osteoarthritis (OA) of the hand, differential regulation of new adipokines vaspin and omentin in synovial fluid of patients with RA compared with OA and the effect of therapy using TNFα inhibitor on the expression profile of adipokines in subcutaneous adipose tissue of RA patients. B cell depletion therapy in RA resulted in decrease of serum levels of visfatin that correlated with following change of disease activity. The levels of IL-35 in synovial fluid are significantly higher in RA than in OA and correlate with the disease activity and functional status. IL-35 subunits p35 and EBI3 are overexpressed in RA..

Is there a potential of circulating miRNAs as biomarkers in rheumatic diseases?

MicroRNAs (miRNAs) are small non-coding single-stranded RNAs of about 22 nucleotides in length that act as post-transcriptional regulators of gene expression. Depending on the complementarity between miRNA and target mRNA, cleavage, destabilization, or translational suppression of mRNA occurs within the RISC (RNA-induced silencing complex). As gene expression regulators, miRNAs are involved in a variety of biological functions. Dysregulation of miRNAs and their target genes contribute to the pathophysiology of many diseases, including autoimmune and inflammatory disorders. MiRNAs are also present extracellularly in their stable form in body fluids. Their incorporation into membrane vesicles or protein complexes with Ago2, HDL, or nucleophosmin 1 protects them against RNases. Cell-free miRNAs can be delivered to another cell in vitro and maintain their functional potential. Therefore, miRNAs can be considered mediators of intercellular communication. The remarkable stability of cell-free miRNAs and their accessibility in body fluid makes them potential diagnostic or prognostic biomarkers and potential therapeutic targets. Here we provide an overview of the potential role of circulating miRNAs as biomarkers of disease activity, therapeutic response, or diagnosis in rheumatic diseases. Many circulating miRNAs reflect their involvement in the pathogenesis, while for plenty, their pathogenetic mechanisms remain to be explored. Several miRNAs described as biomarkers were also shown to be of therapeutic potential, and some miRNAs are already tested in clinical trials

MicroRNAs in rheumatoid arthritis: Potential role in diagnosis and therapy

Rheumatoid arthritis (RA) is a systemic, inflammatory, autoimmune disorder with progressive articular damage that may result in lifelong disability. Although major strides in understanding the disease have been made, the pathogenesis of RA has not yet been fully elucidated. Early treatment can prevent severe disability and lead to remarkable patient benefits, although a lack of therapeutic efficiency in a considerable number of patients remains problematic. MicroRNAs (miRNAs) are small, non-coding RNAs that, depending upon base pairing to messenger RNA (mRNA), mediate mRNA cleavage, translational repression or mRNA destabilization. As fine tuning regulators of gene expression, miRNAs are involved in crucial cellular processes and their dysregulation has been described in many cell types in different diseases. In body fluids, miRNAs are present in microvesicles or incorporated into complexes with Argonaute 2 (Ago2) or high-density lipoproteins and show high stability. Therefore, they are of interest as potential biomarkers of disease in daily diagnostic applications. Targeting miRNAs by gain or loss of function approaches have brought therapeutic effects in various animal models. Over the past several years it has become clear that alterations exist in the expression of miRNAs in patients with RA. Increasing numbers of studies have shown that dysregulation of miRNAs in peripheral blood mononuclear cells or isolated T lymphocytes, in synovial tissue and synovial fibroblasts that are considered key effector cells in joint destruction, contributes to inflammation, degradation of extracellular matrix and invasive behaviour of resident cells. Thereby, miRNAs maintain the pathophysiological process typical of RA. The aim of the current review is to discuss the available evidence linking the expression of miRNAs to inflammatory and immune response in RA and their potential as biomarkers and the novel targets for treatment in patients with RA

Interleukin 35 Synovial Fluid Levels Are Associated with Disease Activity of Rheumatoid Arthritis.

To study the association of systemic and local interleukin-35 (IL-35) levels in rheumatoid arthritis.37 patients with treatment naïve early RA, 49 with established RA and 29 control patients with osteoarthritis (OA) were studied. Serum and paired synovial fluid samples were analysed for IL-35. Disease activity of RA patients was assessed according to the 28-Joint Count Disease Activity Score (DAS28).The levels of serum IL-35 were significantly higher in patients with treatment naïve early RA compared to those with established disease and control OA subjects. In addition, serum levels of IL-35 significantly decreased 12 weeks after initiation of glucocorticoids and conventional synthetic disease modifying antirheumatic drugs in patients with treatment naïve early RA. Synovial fluid IL-35 levels were significantly higher in RA compared to OA patients, were significantly elevated compared to serum counterparts and correlated with synovial fluid leukocyte count (r=0.412; p<0.01), serum CRP levels (r=0.362; p<0.05) and DAS28 (r=0.430, p<0.01).This is the first study showing elevated circulating levels of IL-35 in treatment naïve early RA, its significant decrease after treatment initiation and positive association between increased synovial fluid IL-35 and disease activity in patients with long-lasting RA

Decreased circulating visfatin is associated with improved disease activity in early rheumatoid arthritis: data from the PERAC cohort.

ObjectiveTo evaluate circulating visfatin and its relationship with disease activity and serum lipids in patients with early, treatment-naïve rheumatoid arthritis (RA).MethodsSerum visfatin was measured in 40 patients with early RA before and after three months of treatment and in 30 age- and sex-matched healthy individuals. Disease activity was assessed using the Disease Activity Score for 28 joints (DAS28) at baseline and at three and 12 months. Multivariate linear regression analysis was performed to evaluate whether improved disease activity is related to serum visfatin or a change in visfatin level.ResultsSerum visfatin was significantly elevated in early RA patients compared to healthy controls (1.92±1.17 vs. 1.36±0.93 ng/ml; p = 0.034) and significantly decreased after three months of treatment (to 0.99±0.67 ng/ml; pConclusionA short-term decrease in circulating visfatin may represent an independent predictor of long-term disease activity improvement in patients with early RA

data-dryad

AxSpA patients data for analyses and data table