Hana Hulejová

Increased serum adiponectin levels in female patients with erosive compared with non-erosive osteoarthritis

Adipocytokines including adiponectin and resistin are suggested to be associated with obesity-related complications.1 In general, higher systemic concentrations of resistin and adiponectin compared with paired synovial fluid counterparts were demonstrated in patients with osteoarthritis of the knee.2–4 In contrast, resistin and adiponectin levels were found to be increased at local sites of inflammation in patients with rheumatoid arthritis.3–5 It is suggested that adiponectin in particular actively participates in the process of immune response, inflammation and matrix degradation in destructive arthritides.6 7 Erosive osteoarthritis represents a subtype of generalised osteoarthritis primarily affecting the small joints of the hands, with prominent local inflammation …

Low circulating Dickkopf-1 and its link with severity of spinal involvement in diffuse idiopathic skeletal hyperostosis

Objective Dickkopf-1 (DKK-1) is an inhibitor of osteoblastogenesis, and its lower levels are linked to new bone formation. The aim of this study was therefore to explore serum levels of DKK-1 and to evaluate DKK-1s association with the severity of spinal involvement in diffuse idiopathic skeletal hyperostosis (DISH). Methods Serum levels of total and functional DKK-1 and C-reactive protein (CRP) were measured in 37 patients with DISH and 22 healthy age and sex-matched controls. Plain radiographs of the cervical and thoracic spine were performed, and the diagnosis of DISH was defined using the Resnick criteria. Patients were divided into three groups based on spinal involvement. Bone mineral density (BMD) and bone turnover markers were evaluated in patients with DISH. Results The levels of total serum DKK-1 were significantly lower in patients with DISH than in healthy controls (p<0.0001). Importantly, low serum levels of DKK-1 were associated with more severe spinal involvement in DISH, independent of age, sex, disease duration, CRP, bone turnover markers or BMD. However, these findings were less significant for functional DKK-1. Conclusion These observations indicate that DKK-1 may play a significant role in bone formation during DISH.

Serum hyaluronic acid as a potential marker with a predictive value for further radiographic progression of hand osteoarthritis

OBJECTIVE To compare serum levels of hyaluronic acid (HA) between patients with erosive and non-erosive hand osteoarthritis (HOA), and investigate its association with morphological changes and radiographic progression over 2 years. METHODS Fifty-five women with erosive and 33 women with non-erosive HOA were included in this study. All underwent clinical examination, which included assessment of pain, swelling, deformity and deviation of small hand joints and completed health assessment questionnaires. Serum levels of HA were measured by ELISA. Three-phase bone scintigraphy was performed at baseline. Radiographs of both hands were performed at baseline and after 2 years and scored according Kallman grading scale. RESULTS Serum levels of HA were significantly higher in patients with erosive than with non-erosive HOA (P<0.01). It correlated significantly with the number of hand joints with deviations and deformities. HA adjusted for age and disease duration significantly correlated with radiographs at baseline and after 2 years in all patients with HOA (r=0.560 and r=0.542, P<0.01 for both correlations). Although there was an association between HA and radiographic score in erosive disease, after adjustment for confounders it remained no longer significant. HA adjusted for confounders correlated significantly with the late phase in all patients with HOA (r=0.412, P<0.01) and in patients with erosive disease (r=0.320, P<0.05). CONCLUSION HA is increased in patients with erosive HOA and could be proposed as a surrogate marker with a predictive value for further radiographic progression of HOA in general. Further investigation is necessary to confirm these results.

Metastasis-inducing S100A4 protein is associated with the disease activity of rheumatoid arthritis

OBJECTIVES To evaluate the association between metastasis-inducing protein S100A4 and disease activity in patients with RA, and to demonstrate the effect of TNF-alpha blocking therapy on plasma levels of S100A4 in these patients. METHODS Plasma levels of the S100A4 protein were analysed in 40 anti-TNF-alpha naive patients with active RA. Of the 40 patients, 25 were treated with adalimumab and monitored over time. The conformational form of S100A4 was analysed using size-exclusion gel chromatography. TNF-alpha mRNA expression and protein synthesis were analysed by RT-PCR and ELISA, respectively. RESULTS Baseline levels of S100A4 were significantly correlated with disease activity in RA patients (r = 0.41; P < 0.01). After 12 weeks of treatment with adalimumab, there was an obvious shift in the conformations of S100A4 from the multimeric to the dimeric forms, whereas the total levels of the S100A4 protein remained unchanged. This suggests that the bioactive (multimer) S100A4 may decline in response to successful treatment with adalimumab. In addition, we showed significant up-regulation of TNF-alpha mRNA (P < 0.01), and protein release to the cell culture medium of monocytes stimulated with the S100A4 multimer compared with those treated with the dimer and to the unstimulated monocytes (P < 0.001). CONCLUSIONS This is the first study to show that the levels of the S100A4 protein are correlated with RA disease activity. Furthermore, only the bioactive form, but not the total amount of S100A4, decreases after successful TNF-alpha blocking therapy in patients with RA. These data support an important role for the S100A4 multimer in the pathogenesis of RA.

The level of serum visfatin (PBEF) is associated with total number of B cells in patients with rheumatoid arthritis and decreases following B cell depletion therapy.

OBJECTIVE Visfatin, also known as pre-B cell colony-enhancing factor, was recently characterized as a potent pro-inflammatory mediator in rheumatoid arthritis (RA). The aim of this study was to determine the effect of B cell depletion with rituximab on serum visfatin levels in patients with active RA. METHODS We evaluated 31 patients with RA starting rituximab therapy at baseline and after 16 and 24 weeks using disease activity score (DAS28). The control group consisted of 33 gender and age-matched healthy individuals. CD19(+) B cells were assessed by flow cytometry and serum levels of visfatin and B cell-activating factor of the TNF family (BAFF) were measured by ELISA at baseline and week 16. RESULTS Total number of B cells correlated positively with serum visfatin levels (rs=0.417, P=0.025) and negatively with serum BAFF levels (rs=-0.486, P=0.008) at baseline. Serum visfatin levels were significantly higher in patients with RA compared with healthy controls (P=0.026), and significantly decreased (P=0.010), while BAFF increased (P<0.001), and both proteins became negatively correlated following treatment with rituximab (rs=-0.438, P=0.017). Visfatin levels did not correlate with the disease activity, but lack of change in the serum visfatin levels between baseline and week 16 predicted worsening disease activity between weeks 16 and 24 (rs=0.452, P=0.014). CONCLUSION In patients with active RA, serum visfatin levels are related to the number of B cells rather than to disease activity and decrease in response to treatment with rituximab. Further studies are necessary to show if visfatin is a marker with predictive value for deterioration of RA.

Serum calprotectin (S100A8/9): an independent predictor of ultrasound synovitis in patients with rheumatoid arthritis.

IntroductionCalprotectin, a heterodimeric complex of S100A8/9 (MRP8/14), has been proposed as an important serum biomarker that reflects disease activity and structural joint damage in rheumatoid arthritis (RA). The objective of this cross-sectional study was to test the hypothesis that calprotectin is associated with clinical and ultrasound-determined disease activity in patients with RA.MethodsA total of 37 patients with RA (including 24 females, a mean disease duration of 20 months) underwent a clinical examination and 7-joint ultrasound score (German US-7) of the clinically dominant hand and foot to assess synovitis by grey-scale (GS) and synovial vascularity by power Doppler (PD) ultrasound using semiquantitative 0–3 grading. The levels of serum calprotectin and C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were determined at the time of the ultrasound assessment. We analysed the relationship between serum calprotectin level, traditional inflammatory markers, and ultrasound-determined synovitis.ResultsThe levels of serum calprotectin were significantly correlated with swollen joint count (r = 0.465, p < 0.005), DAS28-ESR (r = 0.430, p < 0.01), ESR (r = 0.370, p < 0.05) and, in particular, CRP (r = 0.629, p < 0.001). Calprotectin was significantly associated with GS (r = 0.359, p < 0.05) and PD synovitis scores (r = 0.497, p < 0.005). Using multivariate regression analysis, calprotectin, adjusted for age and sex, was a better predictor of PD synovitis score (R2 = 0.765, p < 0.001) than CRP (R2 = 0.496, p < 0.001).ConclusionsThe serum levels of calprotectin are significantly associated with clinical, laboratory and ultrasound assessments of RA disease activity. These results suggest that calprotectin might be superior to CRP for monitoring ultrasound-determined synovial inflammation in RA patients.

Pro-inflammatory effects of interleukin-35 in rheumatoid arthritis

OBJECTIVE Interleukin-35 (IL-35) is a heterodimeric member of the IL-12 family consisting of p35/IL-12a and EBI3/IL-27b subunits. Expressed in murine Treg cells, IL-35 controls inflammatory diseases in mouse models. However, human IL-35 is expressed in Teff cells rather than in Treg cells and is shown to be upregulated under inflammatory conditions. Our aim was to examine the involvement of IL-35 in the pathogenesis of rheumatoid arthritis (RA). METHODS Immunohistochemical and immunofluorescence analysis was used to determine the expression and localization of IL-35 and its subunits (p35/EBI3) and IL-35 receptor (IL12Rβ2/gp130) in RA, osteoarthritis (OA) and psoriatic arthritis (PsA) synovial tissues. Expression of p35/EBI3 subunits and release of inflammatory cytokines upon stimulation with IL-35 were assessed in RA synovial fibroblasts (SFs) and peripheral blood mononuclear cells (PBMCs). RESULTS Both IL-35 and its subunits were upregulated in RA in comparison with OA or PsA synovium. Using cell-specific markers, p35 and EBI3 were identified in macrophages, dendritic cells, SFs, and T as well as B cells in RA synovium. Both p35 and EBI3 were induced by TNFα in RASFs and PBMCs. IL-35 dose-dependently upregulated release of pro-inflammatory mediators IL-1β, IL-6 and MCP-1 in PBMCs. While gp130 receptor subunit was upregulated in RA synovium and was expressed in RASFs and PBMCs, there was no difference in IL12Rβ2 expression subunit among tissues and its presence in RASFs was lacking. CONCLUSION Upregulation of IL-35 at sites of inflammation in RA and its pro-inflammatory potential suggests that IL-35 might play an important role in RA pathogenesis.

Adiponectin relation to skin changes and dyslipidemia in systemic sclerosis

OBJECTIVES Adiponectin was initially described as a regulator of metabolic homeostases. Further studies demonstrated its involvement in the regulation of inflammatory diseases, particularly rheumatic and vascular diseases and some fibrotic processes. The aim of this study was to evaluate adiponectin in the circulation of patients with systemic sclerosis (SSc) and characterise its potential association with skin changes and SSc-related features. METHODS Serum levels of adiponectin, interleukin-6 and soluble receptor for interleukin-2 (by ELISA), lipid levels, CRP (by turbidimetry), ANA (by immunofluorescence), autoantibodies of the ENA complex (by immunoblot) and urine levels of pyridinoline and deoxypyridinoline (by HPLC) were measured in 39 patients with SSc, and adiponectin levels were determined in 30 healthy controls matched by age, sex, and body mass index (BMI). Organ manifestations were recorded and skin changes were assessed using the modified Rodnan skin score. RESULTS Adiponectin serum levels were similar between patients with SSc and healthy controls (median (IQR), 6.9 (5.9-9.1) vs. 7.8 (6.2-9.5)μg/ml, p=0.670). Levels of serum (ln) adiponectin were negatively correlated with the skin score (r=-0.379, p=0.017). Regression analysis of the relationship between adiponectin and markers of interest provided two statistically significant models: A- with explanatory variables HDL-cholesterol, skin score, disease duration, age (R(2)=0.580); and B- with CRP, skin score, age (R(2)=0.550); in order of a decreasing influence. CONCLUSION Based on the results of this study, it might be speculated that adiponectin plays a protective role in skin- and atherosclerosis-related changes during SSc.

Interleukin-35 is upregulated in systemic sclerosis and its serum levels are associated with early disease

OBJECTIVES IL-35 is a member of the IL-12 family consisting of p35/IL-12a and EBI3/IL-27b subunits. IL-35 exerts immunomodulatory activities in experimental and human autoimmune inflammatory conditions. Our aim was to assess IL-35 expression in the skin and circulation of SSc patients and to characterize its potential association with SSc-related features. METHODS Expression of IL-35 in skin and dermal fibroblasts was quantified by quantitative PCR, immunohistochemistry and immunofluorescence. Serum levels of IL-35 (by ELISA), CRP (by turbidimetry), ANA (by immunofluorescence) and autoantibodies of the ENA complex (by immunoblot) were measured in 40 SSc patients. Serum IL-35 was determined in 40 age- and sex-matched healthy controls. RESULTS IL-35 expression was increased in SSc skin and dermal fibroblasts in a TGF-β-dependent manner. IL-35 induced an activated phenotype in resting fibroblasts and enhanced the release of collagen. IL-35 serum levels were increased in patients with SSc compared with healthy controls [median 83.9 (interquartile range 45.1-146.1) vs 36.2 (interquartile range 17.2-49.4) pg/ml, P < 0.0001]. Serum IL-35 was negatively correlated with disease duration (r = -0.4339, P = 0.0052). In line with this finding, serum IL-35 was increased in patients with an early SSc pattern on capillaroscopy assessment compared with those with active and late SSc patterns. CONCLUSION The present study demonstrates overexpression of IL-35 in SSc skin, dermal fibroblasts and serum. TGF-β induces IL-35, which in turn activates resting fibroblasts and enhances the release of collagen, thereby contributing to aberrant TGF-β signalling in SSc. Increased serum IL-35 is associated with early, inflammatory stages of SSc.

Resistin in idiopathic inflammatory myopathies

IntroductionThe purpose of this study was to evaluate and compare the serum levels and local expression of resistin in patients with idiopathic inflammatory myopathies to controls, and to determine the relationship between resistin levels, inflammation and disease activity.MethodsSerum resistin levels were determined in 42 patients with inflammatory myopathies and 27 healthy controls. The association among resistin levels, inflammation, global disease activity and muscle strength was examined. The expression of resistin in muscle tissues from patients with inflammatory myopathies and healthy controls was evaluated. Gene expression and protein release from resistin-stimulated muscle and mononuclear cells were assessed.ResultsIn patients with inflammatory myopathies, the serum levels of resistin were significantly higher than those observed in controls (8.53 ± 6.84 vs. 4.54 ± 1.08 ng/ml, P < 0.0001) and correlated with C-reactive protein (CRP) levels (r = 0.328, P = 0.044) and myositis disease activity assessment visual analogue scales (MYOACT) (r = 0.382, P = 0.026). Stronger association was observed between the levels of serum resistin and CRP levels (r = 0.717, P = 0.037) as well as MYOACT (r = 0.798, P = 0.007), and there was a trend towards correlation between serum resistin and myoglobin levels (r = 0.650, P = 0.067) in anti-Jo-1 positive patients. Furthermore, in patients with dermatomyositis, serum resistin levels significantly correlated with MYOACT (r = 0.667, P = 0.001), creatine kinase (r = 0.739, P = 0.001) and myoglobin levels (r = 0.791, P = 0.0003) and showed a trend towards correlation with CRP levels (r = 0.447, P = 0.067). Resistin expression in muscle tissue was significantly higher in patients with inflammatory myopathies compared to controls, and resistin induced the expression of interleukins (IL)-1β and IL-6 and monocyte chemoattractant protein (MCP)-1 in mononuclear cells but not in myocytes.ConclusionsThe results of this study indicate that higher levels of serum resistin are associated with inflammation, higher global disease activity index and muscle injury in patients with myositis-specific anti-Jo-1 antibody and patients with dermatomyositis. Furthermore, up-regulation of resistin in muscle tissue and resistin-induced synthesis of pro-inflammatory cytokines in mononuclear cells suggest a potential role for resistin in the pathogenesis of inflammatory myopathies.