Level of inflammatory cytokines in rheumatoid arthritis patients: Correlation with 25-hydroxy vitamin D and reactive oxygen species

<div><p>Background</p><p>Rheumatoid arthritis (RA) is an autoimmune inflammatory disorder. Reactive oxygen species (ROS) and pro-inflammatory cytokines have been believed to be involved in the etiopathogenesis of the disease. The aim of the study was to determine the correlation of inflammatory cytokines with 25-hydroxy vitamin D and ROS.</p><p>Methods</p><p>100 RA patients and 50 healthy age and sex matched individuals were included in the study. Patients were further divided on the basis of presence or absence of rheumatoid factor and disease severity. Serum 25-hydroxy vitamin D levels were monitored by chemiluminescent immunoassay. 10% hematocrit was used to detect the level of ROS by spectro fluorometer. The levels of inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-10 and IL-17) were determined in plasma by ELISA.</p><p>Results</p><p>The level of 25-hydroxy vitamin D was found to be decreased in RA patients in comparison to the control group. However the level of ROS and inflammatory cytokines were found to be elevated in RA patients in comparison with the healthy controls, with the increase being more pronounced in seropositive and RA patients having high disease severity. Inflammatory cytokines showed negative correlation with 25-hydroxy vitamin D and positive correlation with ROS.</p><p>Conclusion</p><p>This study for the first time shows the association of inflammatory cytokines with 25-hydroxy vitamin D and ROS in RA patients. The results suggest that 25-hydroxy vitamin D being an immune modulator is decreased in the serum of RA patients. Further ROS and cytokines play an important role in the pathogenesis of RA and are responsible for increasing the severity of disease.</p></div

Baseline characteristics of healthy controls and rheumatoid arthritis patients.

<p>The values represents the mean ± S.D.</p

Serum level of 25-hydroxy vitamin D in controls and RA patients (Fig A), seropositive and seronegative RA patients (Fig B) and patients having DAS28≤3.2 and those having DAS28>3.2 (Fig C).

<p>(***p<0.001).</p

Correlation analysis of plasma levels of cytokines with 25-hydroxy vitamin D and reactive oxygen species.

<p>Correlation analysis of plasma levels of cytokines with 25-hydroxy vitamin D and reactive oxygen species.</p

Correlation between 25 (OH) D and NO (Fig A), GSH (Fig B), TNF-α (Fig C), IL-1β (Fig D), IL-6 (Fig E), IL-10 (Fig F) and IL-17 (Fig G).

<p>Correlation between 25 (OH) D and NO (Fig A), GSH (Fig B), TNF-α (Fig C), IL-1β (Fig D), IL-6 (Fig E), IL-10 (Fig F) and IL-17 (Fig G).</p

Correlation between ROS and NO (Fig A), GSH (Fig B), TNF-α (Fig C), IL-1β (Fig D), IL-6 (Fig E), IL-10 (Fig F) and IL-17 (Fig G).

<p>Correlation between ROS and NO (Fig A), GSH (Fig B), TNF-α (Fig C), IL-1β (Fig D), IL-6 (Fig E), IL-10 (Fig F) and IL-17 (Fig G).</p

Increased Reactive Oxygen Species Formation and Oxidative Stress in Rheumatoid Arthritis

<div><p>Background</p><p>Rheumatoid arthritis (RA) is an autoimmune inflammatory disorder. Highly reactive oxygen free radicals are believed to be involved in the pathogenesis of the disease. In this study, RA patients were sub-grouped depending upon the presence or absence of rheumatoid factor, disease activity score and disease duration. RA Patients (120) and healthy controls (53) were evaluated for the oxidant—antioxidant status by monitoring ROS production, biomarkers of lipid peroxidation, protein oxidation and DNA damage. The level of various enzymatic and non-enzymatic antioxidants was also monitored. Correlation analysis was also performed for analysing the association between ROS and various other parameters.</p><p>Methods</p><p>Intracellular ROS formation, lipid peroxidation (MDA level), protein oxidation (carbonyl level and thiol level) and DNA damage were detected in the blood of RA patients. Antioxidant status was evaluated by FRAP assay, DPPH reduction assay and enzymatic (SOD, catalase, GST, GR) and non-enzymatic (vitamin C and GSH) antioxidants.</p><p>Results</p><p>RA patients showed a higher ROS production, increased lipid peroxidation, protein oxidation and DNA damage. A significant decline in the ferric reducing ability, DPPH radical quenching ability and the levels of antioxidants has also been observed. Significant correlation has been found between ROS and various other parameters studied.</p><p>Conclusion</p><p>RA patients showed a marked increase in ROS formation, lipid peroxidation, protein oxidation, DNA damage and decrease in the activity of antioxidant defence system leading to oxidative stress which may contribute to tissue damage and hence to the chronicity of the disease.</p></div

Comparison of blood plasma and hemolysate parameters in RA patients sub-grouped according to the duration of the RA: newly diagnosed (ND), less than years (≤ 2 years) and between 2–5 years.

<p>Comparison of blood plasma and hemolysate parameters in RA patients sub-grouped according to the duration of the RA: newly diagnosed (ND), less than years (≤ 2 years) and between 2–5 years.</p

Bar graph representation of data from DCFH-DA assay on lymphocytes of control and RA patients.

<p>Fluorescence intensity was recorded at 530 nm using excitation wavelength of 485 nm. Results are mean ± S.D. (*p < 0.05 vs control).</p

Comparison of the DCF formed in control and RA patients sub-grouped according to the duration of RA: newly diagnosed (ND), less than or equal to 2 years (≤ 2 years) and between 2–5 years.

<p>(*p < 0.05 vs control).</p