Interleukin-10 and interleukin-6 in lupus erythematosus and rheumatoid arthritis, correlations with acute phase proteins

Summary We sought to investigate the influence of interleukin-10 (IL10) and IL-6 on the acute phase proteins (APP) in systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). IL-10, IL-6, Creative protein (CRP), alpha-1-acid glycoprotein (AGP), and alpha1 antichymotrypsin (ACT) serum levels were determined in one hundred-eight patients (71 with SLE, 37 with RA).Quantification of the serum IL-10 level showed increased levels in SLE and RA patients as compared to healthy controls. Serum IL-6 level was found to be elevated in SLE and RA patients. A correlation between IL-10 and IL-6 serum level was found only in SLE. CRP and AGP serum levels were increased in RA as compared to controls, whereas in SLE only AGP was found elevated. A statistically significant correlation between IL-6 serum level and CRP, AGP and ACT was found only in RA. No correlation between IL-10 and serum level of CRP, AGP and ACT was established.Since IL-10 has a potent immunosuppressive activity, we expected it to be negatively correlated with APP levels. Surprisingly, IL-10 did not correlate with APP either in SLE or RA patients. However, the elevation of IL-10 serum levels in SLE and RA and the correlation between IL-10 and IL-6 in SLE may suggest that IL-10 may play a central role in inflammatory connective tissue diseases.     

Th-17 associated cytokines in patients with reactive arthritis/undifferentiated spondyloarthropathy

We and others have previously shown that IL-17 is elevated in the synovial fluid of patients with reactive arthritis (ReA)/undifferentiated spondyloarthropathy (uSpA) having acute synovitis. Major source for IL-17 is Th17 cells, which differentiate from Th0 cells under the influence of TGF-β and IL-6, IL1-β and are maintained by IL-21 and 23. There is a paucity of data on these cytokines in ReA/uSpA. Thus, we measured the levels of Th-17 differentiating and maintaining cytokines in synovial fluid of patients with ReA and uSpA. Fifty patients with ReA/uSpA (ReA 24, uSpA 26), 19 patients with rheumatoid arthritis (RA) and 11 patients with osteoarthritis (OA) were included in the study. Synovial fluid (SF) were collected from knee joint and stored at −80°C until analysis. Cytokines were assayed using ELISA in SF specimens. The median IL-17A levels were significantly elevated in ReA (48.3 pg/ml) and uSpA (32.5 pg/ml) as compared to non-inflammatory OA controls (<7.8 pg/ml; p < 0.0001), while comparable to RA (57.9 pg/ml). Further, IL-6 median values were higher in ReA (25.2 ng/ml) and uSpA (13.6 ng/ml) as compared to OA (0.76 ng/ml; p < 0.0001), and comparable to RA (15.8 ng/ml). The median levels of IL-1β, IL-21 levels were elevated in ReA, uSpA and RA as compared to OA but were not statistically significant. TGF-β levels in ReA and uSpA were similar to OA but lower than in RA (4340 pg/ml; p < 0.05). IL-23 was not detectable in any synovial fluid sample. However, levels of these cytokines did not correlate with disease activity parameters. Significant positive correlation was observed between IL-17 and IL-1β (r = 0.38, p < 0.005), IL-17 and IL-6 (r = 0.659, p < 0.0001), and IL-1β and IL-6 (r = 0.391, p < 0.0001) in ReA and uSpA group. Inflammatory synovitis in ReA/uSpA is mediated by pro-inflammatory cytokines like IL-17, IL-6, IL-1β, and IL-21. However, IL-23 was not detectable in SF. Good correlation between IL-17, IL-6, and IL 1β suggest that either they are co-regulated or they regulate each other.     

Serum levels of cartilage oligomeric matrix protein (COMP): a rapid decrease in patients with active rheumatoid arthritis undergoing intravenous steroid treatment

To examine the influence of intravenous steroid-treatment (IST) on serum levels of Cartilage oligomeric matrix protein (COMP) in patients with active rheumatoid arthritis (RA). Serum levels of COMP and C-reactive protein (CRP) were measured in 12 patients with highly active RA (Steinbrocker stages II–IV) and in 5 patients with highly active reactive arthritis (ReA) (positive testing for HLA-B27) before starting daily IST. Patients received a total steroid dosage between 100 and 500 mg of prednisolone. COMP was measured by a commercially available sandwich-type ELISA-kit developed by AnaMar Medical AB, Sweden. Statistical evaluation was calculated by paired t test. In the RA group, COMP levels ranged from 6.3 to 19.4 U/l (mean 12.9 U/l), CRP from 5 to 195 mg/l (mean 77.8 mg/l), the COMP levels of the ReA group ranged from 5.1 to 7.4 U/l (mean 7.9 U/l), the CRP levels from 13 to 126 mg/l (mean 49 mg/l). We found a significant difference between the initial COMP levels in RA+ and ReA patients (P<0.005). In contrast to the ReA group, serum-COMP levels of RA+ patients (P<0.004) and the VAS (P<0.0001) decreased significantly within 2–10 days after the first treatment with steroids. The CRP levels remained unchanged in both groups. Our results indicate that the intravenous treatment with steroids in patients with highly active RA leads to a significant decrease of cartilage degradation. COMP seems to be a valuable parameter not even as a prognostic factor, but as a marker for monitoring the therapy response in patients with RA.     

Different monocyte reaction patterns in newly diagnosed,untreated rheumatoid arthritis and lupus patients probably confer disparate C-reactive protein levels

OBJECTIVES: To investigate the different capacities of monocytes to produce cytokines in newly diagnosed, untreated patients with rheumatoid arthritis (RA) or systemic lupus and to examine the possible correlation among serum C-reactive protein (CRP), cytokines, swollen joint counts, and erythrocyte sedimentation rates (ESR) in untreated RA patients. METHODS: Monocytes from untreated RA or lupus patients were cultured in vitro with lipopolysaccharide (LPS, as bacterial infection) or immune complexes (as endogenous immune deviation) and supernatants were collected for cytokine determination. Sera from RA patients were assayed for interleukin-6 (IL-6), IL-1 beta, IL-10, tumor necrosis factor-alpha (TNF-alpha) and IL-1 receptor antagonist (IL-1ra). These cytokines were related to serum CRP, swollen joint counts, and ESR. RESULTS: RA monocytes uniformly produced IL-6, IL-1 beta, TNF-alpha, or IL-10 in vitro. In contrast, lupus monocytes could be divided into two subsets: (i) monocytes which produce cytokines on LPS stimulation but not on challenging with immune complexes; and (ii) monocytes which, interestingly, generate cytokines on stimulation by immune complexes but not LPS. These cytokines in turn stimulate the liver to synthesize CRP differently in the SLE subsets and RA patients. Moreover, serum IL-1ra levels correlated significantly with serum IL-6, IL-1 beta, and TNF-alpha concentrations (p = 0.005, 0.008, or 0.040, respectively), but not with IL-10 (p = 0.582) in RA patients. CONCLUSIONS: Two lupus subsets exist that react either to LPS or immune complexes to produce CRP-inducing cytokines, in contrast to homogeneous RA monocytes. This is the first report that different reaction patterns of CRP-inducing cytokine production in RA and lupus monocytes probably underlie the high CRP levels in RA versus low heterogeneity in lupus. The correlation of serum IL-1ra levels with serum IL-6, IL-1 beta, or TNF-alpha concentrations, and the borderline correlation of the former with CRP levels, demonstrate that IL-1ra is an acute phase reactant in RA as well as in SLE patients.     

Soluble urokinase plasminogen activator receptor in plasma of patients with inflammatory rheumatic disorders: increased concentrations in rheumatoid arthritis

OBJECTIVE—Urokinase type plasminogen activator (uPA) catalyses the formation of the proteolytic enzyme plasmin, which is involved in matrix degradation in the processes of tissue remodelling. Because of a surface bound uPA receptor (uPAR), expressed by some cell types (for example, macrophages, malignant cells and inflammatory activated synoviocytes), the action of uPA can be localised and intensified. uPAR seems to have a role in the mechanisms leading to invasive growth of malignant tissue and the rheumatoid pannus. uPAR may become cleaved at its cell surface anchor, thus forming a free soluble receptor (suPAR). suPAR is detectable in low but constant values in plasma of healthy people, while increased concentrations are found in patients with disseminated malignant disease, so that suPAR may be an indicator of invasive growth and tissue remodelling. suPAR concentrations in plasma have not previously been measured in rheumatic patients. A controlled cross sectional measurement was performed of suPAR in plasma of patients with various inflammatory rheumatic disorders with special reference to rheumatoid arthritis (RA).
METHODS—suPAR in plasma was measured by ELISA technique in patients with RA (n=51), reactive arthritis (ReA) (n=23), primary Sjögren''s syndrome (PSS) (n=42) and sex and age matched healthy controls (n=53).
RESULTS—In the control group suPAR (median) was 0.91 (range 0.56-1.94) µg/l. Median suPAR value in RA was 1.47 (range 0.65-6.62) µg/l; in ReA 0.68 µg/l (range 0.52-1.48) and in PSS 1.12 µg/l (range 0.76-1.92); p versus controls <0.001 in all patient groups. suPAR values in RA were also significantly increased compared with ReA (p<0.001) and PSS (p=0.004) groups. suPAR in RA was positively correlated to C reactive protein (CRP) (p<0.01) and erythrocyte sedimentation rate (p<0.05) and number of swollen joints (p<0.05). The ReA group had the highest CRP values of all groups, but at the same time the lowest suPAR concentrations in plasma.
CONCLUSIONS—Increased suPAR concentrations were found in plasma in RA, and to a smaller extent also in PSS, but not in ReA. In RA suPAR is related to disease activity. suPAR seems though not merely to be an acute phase reactant like CRP. Increased suPAR values might reflect erosive activity in RA.

     

Inflammatory cytokines,endothelial markers and adhesion molecules in rheumatoid arthritis: effect of intensive anti-inflammatory treatment

Tumour necrosis factor alpha (TNF-α) and interlekin-6 (IL-6) are key inflammatory cytokines in the pathogenesis of rheumatoid arthritis (RA), a disease also associated with endothelial perturbation and increased serum levels of adhesion molecules. As relationships between these processes and molecules are unclear, we tested the hypotheses (a) that TNF-α and IL-6 are linked to endothelial activation/damage and levels of soluble adhesion molecules, and (b) that intensive anti-inflammatory treatment improves levels of these indices. We recruited 66 patients with RA, 48 community controls (CC), and 25 disease controls (DC). Plasma TNF-α and IL-6 were compared to markers of vascular biology (vWF, sE-sel), soluble adhesion molecules (sICAM, sVCAM) and routine inflammatory markers (CRP and ESR). Blood was obtained at baseline and at 1 week and again 4 weeks after anti-inflammatory treatment in a subgroup of 29 patients with RA. With the exception of sE-selectin, RA patients had increased levels of all plasma markers compared to the HCs, whilst levels in the DCs were largely intermediate between RA and the CCs. Within the RA group, sEsel correlated with both CRP and ESR whilst TNF-α correlated with sVCAM (all r > 0.32, P < 0.01). After 1 week of combined anti-inflammatory therapy, only CRP, ESR, sEsel and sVCAM were significantly reduced (all P < 0.05). In RA, endothelial activation (as sEsel) correlates with classical markers of inflammation and is reduced by intensive anti-inflammatory medications.     

Cellular and humoral markers of systemic inflammation in acute reactive arthritis and early rheumatoid arthritis

OBJECTIVE: To compare systemic inflammation in reactive arthritis (ReA), rheumatoid arthritis (RA), and sepsis using novel markers of systemic inflammation, and to study whether they are helpful in distinguishing between ReA and RA. METHODS: In 28 patients with acute ReA, 16 patients with early untreated RA, and 25 patients with blood culture-positive sepsis, phagocyte CD 11b expression was measured by flow cytometry, serum procalcitonin (PCT) levels by immunoluminometric assay, and soluble E-selectin (sE-selectin) levels by enzyme-linked immunosorbent assay (ELISA). RESULTS: Neutrophil and monocyte CD11b expression and serum levels of PCT and sE-selectin were higher in patients with sepsis than patients with ReA or RA, or in healthy subjects (all p < 0.01). They were comparable in healthy subjects, ReA, and RA. CONCLUSION: Patients with acute ReA and early RA have normal CD11b expression levels on phagocytes and normal PCT and sE-selectin levels in serum. Elevated levels suggest possible sepsis.     

B-lymphocyte activating factor in systemic lupus erythematosus and rheumatoid arthritis in relation to autoantibody levels, disease measures and time

Overexpression of B-lymphocyte activating factor (BAFF) results in arthritis, glomerulonephritis and autoantibody formation in mice, but its role in human autoimmune disease is less obvious. Serum BAFF levels in patients with systemic lupus erythematosus (SLE) (n=42) and rheumatoid arthritis (RA) (n=60) were related to levels of disease activity, anti-dsDNA Ab, anti-ENA Ab, rheumatoid factor (RF) and anti-CCP Ab. BAFF levels were also followed over time in 19 SLE patients. BAFF levels correlated inversely with age, were higher in SLE than RA (median 2.7 versus 1.4 ng/mL, P < 0.01) and more SLE than RA patients had increased BAFF levels (57% versus 10%, P < or = 0.01). In SLE, BAFF levels correlated with SLEDAI scores but not with anti-dsDNA Ab levels. SLE patients with increased BAFF levels had higher SLEDAI and CRP levels. In RA, BAFF levels correlated weakly with anti-CCP levels (Rs 0.27, P = 0.07), but not with joint counts, ESR, CRP or RF levels. Longitudinal BAFF levels remained unaltered in two thirds of SLE patients and changes in BAFF levels were unrelated to disease flares. These findings suggest that BAFF stimulation of B-cells may contribute to SLE by other mechanisms than autoantibody production.     

Inadequately low serum levels of steroid hormones in relation to interleukin-6 and tumor necrosis factor in untreated patients with early rheumatoid arthritis and reactive arthritis

OBJECTIVE: To compare levels of steroid hormones in relation to cytokines and to study levels of cortisol or dehydroepiandrosterone (DHEA) in relation to other adrenal hormones in untreated patients with early rheumatoid arthritis (RA) and reactive arthritis (ReA) compared with healthy controls. METHODS: In a retrospective study with 34 RA patients, 46 ReA patients, and 112 healthy subjects, we measured serum levels of interleukin-6 (IL-6), tumor necrosis factor (TNF), adrenocorticotropic hormone (ACTH), cortisol, 17-hydroxyprogesterone (17-OH-progesterone), androstenedione (ASD), DHEA, and DHEA sulfate (DHEAS). RESULTS: RA patients had higher serum levels of IL-6, TNF, cortisol, and DHEA compared with ReA patients and healthy subjects, but no difference was noticed with respect to ACTH and DHEAS. However, in RA and ReA patients compared with healthy subjects, levels of ACTH, cortisol, ASD, DHEAS, and 17-OH-progesterone were markedly lower in relation to levels of IL-6 and TNF. Furthermore, the number of swollen joints correlated inversely with the ratio of serum cortisol to serum IL-6 in RA (R(Rank) = -0.582, P = 0.001) and, to a lesser extent, in ReA (R(Rank) = -0.417, P = 0.011). In RA patients, the mean grip strength of both hands was positively correlated with the ratio of serum cortisol to serum IL-6 (R(Rank) = 0.472, P = 0.010). Furthermore, in these untreated patients with RA and ReA, there was a relative decrease in the secretion of 17-OH-progesterone, ASD, and DHEAS in relation to DHEA and cortisol. This indicates a relative predominance of the nonsulfated DHEA and cortisol in relation to all other measured adrenal steroid hormones in the early stages of these inflammatory diseases. CONCLUSION: This study indicates that levels of ACTH and cortisol are relatively low in relation to levels of IL-6 and TNF in untreated patients with early RA and ReA compared with healthy subjects. The study further demonstrates that there is a relative increase of DHEA and cortisol in relation to other adrenal hormones, such as DHEAS. This study emphasizes that adrenal steroid secretion is inadequately low in relation to inflammation. Although changes in hormone levels are similar in RA and ReA, alteration of steroidogenesis is more pronounced in RA patients than in ReA patients.     

Biomarkers of inflammation in patients with unclassified polyarthritis and early rheumatoid arthritis. Relationship to disease activity and radiographic outcome

OBJECTIVE: To determine plasma interleukin 6 (pIL-6), plasma vascular endothelial growth factor (pVEGF), and serum (s) YKL-40 in patients with early rheumatoid arthritis (RA) and unclassified polyarthritis (PA), and investigate their relationship with radiographic outcome. METHODS: pIL-6 and pVEGF were determined by ELISA and sYKL-40 by an in-house radioimmunoassay in 51 patients with early RA and 21 with PA. Patients were followed with clinical and biochemical measurement every month for 2 years. Conventional radiographs of hands, wrists, and forefeet were scored according to the Larsen method, and magnetic resonance imaging of 2nd to 5th metacarpophalangeal joints of the dominant hand were evaluated for presence or absence of bone erosions. RESULTS: Baseline pIL-6, pVEGF, sYKL-40, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were elevated in RA patients compared to healthy persons (p < 0.001), but were not in patients with PA. Patients with early RA had higher pIL-6 (p = 0.007), pVEGF (p = 0.02), and sYKL-40 (p = 0.024) compared to PA patients. pIL-6, sYKL-40, CRP, and ESR but not pVEGF decreased in patients that responded to treatment after 2 years. The mean value of pIL-6 during the first and second year were higher in patients with early RA with progression in bone erosions (n = 14) compared to early RA patients without progression (n = 30; first year 8.4 vs 2.8 ng/l, p = 0.04; second year 6.1 vs 3.6 ng/l, p = 0.03). CONCLUSION:Plasma IL-6 was the only biomarker related to treatment response and progressive erosive disease in patients with early RA, but it may not give additional information compared to CRP in relation to disease activity and treatment response.     

Plasma adrenomedullin and proadrenomedullin N-terminal 20 peptide in patients diagnosed as having early rheumatoid arthritis

Abstract

The aim of this study was to investigate plasma adrenomedullin (AM) and proadrenomedullin N-terminal 20 peptide (PAMP) level in patients diagnosed with early rheumatoid arthritis (RA). Furthermore, several inflammatory cytokines were measured in those patients to clarify the roles of AM and PAMP. Forty patients diagnosed with early RA (women 46 ± 8.5 years old) and 10 healthy controls (women 57 ± 5 years old) were studied. Plasma levels of AM, PAMP, matrix metalloprotease 3 (MMP-3), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α), and C-reactive protein (CRP) were measured using an immunoradiometric assay and enzyme-linked immunosorbent asay (ELISA) methods. The plasma levels of AM (17.5 ± 8.4 fmol/ml) and PAMP (2.01 ± 0.57 fmol/ml) in patients exceeded those in healthy controls (AM 8.6 ± 1.7, PAMP 1.17 ± 0.34 fmol/ml). Moreover, plasma AM and PAMP levels demonstrated a significantly positive correlation with plasma MMP-3 and IL-6 levels. Nevertheless, CRP and TNF-α levels in these patients showed no significant correlation with plasma AM and PAMP levels. These data support the possible role for AM and PAMP in the pathophysiology of early RA.     

Clinical presentations of chlamydial and non-chlamydial reactive arthritis

The aim of this study was to investigate the triggering micro-organisms and the clinical as well as laboratory differences between Chlamydial and non-chlamydial reactive arthritis (ReA) in a prospective study on 98 patients with acute/subacute arthritis. An inciting organism was found in 42 patients. Eighteen of these were chlamydial. Fifty-seven percent of all ReA patients were carriers for HLA-B27, which increased to 67% in the chlamydial group. Chlamydial ReA patients had more urethritis (P<0.05) with a longer period between arthritis and inciting infection, significantly lower CRP levels, and involved joint counts (P<0.05). Additionally, sacroiliitis was more frequent besides extra-articular manifestations in chlamydial ReA group. This study shows that chlamydial ReA differs in some points from non-chlamydial ReA, which in turn may affect the evaluation of an arthritic patient. ReA due to chlamydia more frequently encompasses a monoarticular or oligoarticular clinical picture with predominant distal extremity involvement. Non-chlamydial ReA presents higher joint counts and may involve upper extremity joints.     

Clinical characteristics of anti-glucose-6-phosphate isomerase antibody-positive Japanese patients with rheumatoid arthritis

Anti-glucose-6-phosphate isomerase (GPI) antibodies (Abs) are known to be arthritogenic in mice. These Abs are elevated in several forms of arthritic condition in humans, although their prevalence in rheumatoid arthritis (RA) patients is still in debate. Some RA patients have increased levels of anti-GPI Abs, but their clinical manifestation and relevance to other Abs are not clearly elucidated. The aims of this study were to explore the clinical and hematological characteristics of RA with anti-GPI Abs, and to compare their prevalence in RA patients, systemic lupus erythematosus (SLE) patients, and healthy subjects (HS) in a Japanese population. Anti-GPI Abs were positive in 16 patients with RA (12%, n = 137), in 10 patients with SLE (8%, n = 131), and in 6 HS (4%, n = 139). C-reactive protein (CRP), immunoglobulin G, and the antinuclear antibody titer were higher in anti-GPI-positive patients than in those who were negative (P = 0.049, P = 0.0003, and P = 0.002, respectively). Moreover, the positivity of anti-GPI Abs was correlated with CRP more than with rheumatoid factor in RA patients. It is unclear whether anti-GPI Abs can predict the progress of disease, but the prevalence of these Abs was higher in active RA patients with severe arthritis, suggesting that anti-GPI Abs may be related to the pathogenesis of severe forms of arthritis.     

Rheumatoid arthritis treated with tenidap and piroxicam clinical associations with cytokine modulation by tenidap

Objective. To compare the effects of tenidap and piroxicam on acute-phase protein and cytokine levels in the blood of rheumatoid arthritis (RA) patients and to explore their associations with clinical disease activity. Methods. A double-blind, randomized, crossover trial in 49 patients with active RA compared 6 weeks of treatment with tenidap (120 mg/day) versus 6 weeks of treatment with piroxicam (20 mg/day). Results. Median values for C-reactive protein (CRP), Westergren erythrocyte sedimentation rate (ESR), serum amyloid A (SAA) protein, and interleukin-6 (IL-6) were significantly lower after tenidap treatment compared with piroxicam treatment, even in the presence of stable background treatment with prednisone, methotrexate, or prednisone plus methotrexate. The median within-patient treatment differences (after tenidap minus after piroxicam) in the CRP, ESR, SAA, and IL-6 values were –1.7 mg/dl, –10.0 mm/hour, –22.0 μg/ml, and –3.7 pg/ml, respectively, and represent –60.4%, –17.7%, –35.5%, and –26.1% of the respective baseline levels. IL-6 levels were positively correlated with CRP and SAA. Plasma IL-1β was generally below the level of detection. Tumor necrosis factor α levels were similar after tenidap and after piroxicam. Treatment differences for 4 of 7 clinical parameters favored tenidap, but did not reach statistical significance. IL-6, CRP, and ESR were significantly correlated with clinical treatment differences. Tenidap and piroxicam toleration were similar, although tenidap treated patients exhibited a reversible increase in urinary protein excretion. Conclusion. Tenidap was differentiated from piroxicam by lower levels of acute-phase proteins, ESR, and IL-6 after tenidap treatment. These treatment differences were significantly correlated with clincial parameters.     

Inflammation-associated insulin resistance: differential effects in rheumatoid arthritis and systemic lupus erythematosus define potential mechanisms

OBJECTIVE: Insulin resistance is increased by inflammation, but the mechanisms are unclear. The present study was undertaken to test the hypothesis that decreased insulin sensitivity is differentially associated with mediators of inflammation by studying 2 chronic inflammatory diseases of different pathogenesis, systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). METHODS: We measured fasting insulin, glucose, and lipid levels, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor alpha (TNFalpha), and coronary artery calcification in 103 patients with SLE and in 124 patients with RA. Insulin sensitivity was measured using the homeostasis model assessment (HOMA) index. RESULTS: The HOMA value was higher in RA patients (median 2.05 [interquartile range (IQR) 1.05-3.54]) than in SLE patients (1.40 [0.78-2.59]) (P = 0.007). CRP and ESR did not differ significantly in RA and SLE patients. Body mass index (BMI) was significantly correlated with the HOMA index in both RA (rho = 0.20) and SLE (rho = 0.54), independently of age, sex, race, and current use of corticosteroids. In RA patients, the HOMA index was also significantly positively correlated with IL-6 (rho = 0.63), TNFalpha (rho = 0.50), CRP (rho = 0.29), ESR (rho = 0.26), coronary calcification (rho = 0.26), and Disease Activity Score in 28 joints (rho = 0.21); associations adjusted for age, sex, race, BMI, and current use of corticosteroids remained significant (P < 0.05). In SLE patients, the HOMA index was also significantly correlated with ESR (rho = 0.35) and CRP (rho = 0.25), but not with other variables. The association between the ESR and the HOMA value in patients with SLE remained significant after adjustment for confounding covariates (P = 0.008). In multivariable models, the major contributing factors to the HOMA index were the BMI in SLE patients, and IL-6 and TNFalpha levels in RA patients. CONCLUSION: The pathogenesis of insulin resistance and its contribution to atherogenesis varies in different inflammatory settings.     

Inadequately low serum levels of steroid hormones in relation to interleukin‐6 and tumor necrosis factor in untreated patients with early rheumatoid arthritis and reactive arthritis

Objective

To compare levels of steroid hormones in relation to cytokines and to study levels of cortisol or dehydroepiandrosterone (DHEA) in relation to other adrenal hormones in untreated patients with early rheumatoid arthritis (RA) and reactive arthritis (ReA) compared with healthy controls.

Methods

In a retrospective study with 34 RA patients, 46 ReA patients, and 112 healthy subjects, we measured serum levels of interleukin‐6 (IL‐6), tumor necrosis factor (TNF), adrenocorticotropic hormone (ACTH), cortisol, 17‐hydroxyprogesterone (17‐OH‐progesterone), androstenedione (ASD), DHEA, and DHEA sulfate (DHEAS).

Results

RA patients had higher serum levels of IL‐6, TNF, cortisol, and DHEA compared with ReA patients and healthy subjects, but no difference was noticed with respect to ACTH and DHEAS. However, in RA and ReA patients compared with healthy subjects, levels of ACTH, cortisol, ASD, DHEAS, and 17‐OH‐progesterone were markedly lower in relation to levels of IL‐6 and TNF. Furthermore, the number of swollen joints correlated inversely with the ratio of serum cortisol to serum IL‐6 in RA (R_Rank = −0.582, P = 0.001) and, to a lesser extent, in ReA (R_Rank = −0.417, P = 0.011). In RA patients, the mean grip strength of both hands was positively correlated with the ratio of serum cortisol to serum IL‐6 (R_Rank = 0.472, P = 0.010). Furthermore, in these untreated patients with RA and ReA, there was a relative decrease in the secretion of 17‐OH‐progesterone, ASD, and DHEAS in relation to DHEA and cortisol. This indicates a relative predominance of the nonsulfated DHEA and cortisol in relation to all other measured adrenal steroid hormones in the early stages of these inflammatory diseases.

Conclusion

This study indicates that levels of ACTH and cortisol are relatively low in relation to levels of IL‐6 and TNF in untreated patients with early RA and ReA compared with healthy subjects. The study further demonstrates that there is a relative increase of DHEA and cortisol in relation to other adrenal hormones, such as DHEAS. This study emphasizes that adrenal steroid secretion is inadequately low in relation to inflammation. Although changes in hormone levels are similar in RA and ReA, alteration of steroidogenesis is more pronounced in RA patients than in ReA patients.

     

Clinical characteristics of anti-glucose-6-phosphate isomerase antibody-positive Japanese patients with rheumatoid arthritis

Abstract

Anti-glucose-6-phosphate isomerase (GPI) antibodies (Abs) are known to be arthritogenic in mice. These Abs are elevated in several forms of arthritic condition in humans, although their prevalence in rheumatoid arthritis (RA) patients is still in debate. Some RA patients have increased levels of anti-GPI Abs, but their clinical manifestation and relevance to other Abs are not clearly elucidated. The aims of this study were to explore the clinical and hematological characteristics of RA with anti-GPI Abs, and to compare their prevalence in RA patients, systemic lupus erythematosus (SLE) patients, and healthy subjects (HS) in a Japanese population. Anti-GPI Abs were positive in 16 patients with RA (12%, n = 137), in 10 patients with SLE (8%, n = 131), and in 6 HS (4%, n = 139). C-reactive protein (CRP), immunoglobulin G, and the antinuclear antibody titer were higher in anti-GPI-positive patients than in those who were negative (P = 0.049, P = 0.0003, and P = 0.002, respectively). Moreover, the positivity of anti-GPI Abs was correlated with CRP more than with rheumatoid factor in RA patients. It is unclear whether anti-GPI Abs can predict the progress of disease, but the prevalence of these Abs was higher in active RA patients with severe arthritis, suggesting that anti-GPI Abs may be related to the pathogenesis of severe forms of arthritis.     

Substance p and arthritis: analysis of plasma and synovial fluid levels

The uncadecapeptide substance P (SP), which is localized in peripheral and central terminals of afferent nerve fibers with polymodal nociceptors, has recently been implicated as having a neurogenic, inflammatory role in experimental arthritis. We used a radioimmunoassay to measure SP levels in plasma and synovial fluid samples from patients with rheumatoid arthritis (RA), osteoarthritis (OA), Reiter's syndrome (RS), and posttraumatic arthritis, as well as in plasma samples from 13 normal subjects. Plasma SP levels in RS patients exceeded levels in RA and OA patients, which in turn exceeded levels in posttrauma patients and in normal subjects. Synovial fluid SP levels exceeded respective plasma levels for all groups, except in RS patients, in whom the plasma level was not significantly different from that in synovial fluid. SP levels in synovial fluid of RA, OA, and RS patients did not differ significantly from each other, but the level in posttrauma patients was higher than in all other groups (P > 0.005). These studies demonstrate localized intraarticular SP release, and significant plasma/synovial fluid SP concentration gradients in several forms of arthritis.     

Change in biomarkers of osteoporosis in rheumatoid arthritis patients treated with infliximab

A study was made to evaluate bone turn-over in rheumatoid arthritis (RA) patients treated with infliximab. Twenty-two patients with established RA were included. In all patients, biochemical markers of osteoporosis: osteocalcin (BGP), alkaline phosphatase (bone isoenzyme), deoxypyridinoline (Dpd), acute phase proteins (CRP, AGP, ACT, AGP-RC), and interleukin 6 (IL-6) were determined before treatment, at week 30, and at week 46. Two markers (BGP, Dpd) were significantly decreased at both weeks 30 and 46. Moreover, a fall in serum levels of acute phase proteins and IL-6 was seen. The results suggest that anti-TNF treatment with infliximab not only decreases activity of inflammation but also may slow down bone turn-over. Further research is needed to assess its potential in reducing risk of osteoporosis in RA.