carbocyanines and Arthritis--Rheumatoid

Rheumatoid arthritis synovial fibroblasts (RASFs) are known to travel via the bloodstream from sites of cartilage destruction to new locations where they reinitiate the destructive processes at distant articular cartilage surfaces. In this study, we examined the role of interleukin (IL)-1-induced cartilage changes and their chemotactic effect on RASF transmigratory capacity.. To investigate synovial fibroblast (SF) transmigration through endothelial layers, we used a modified Boyden chamber with an endothelioma cell layer (bEnd.5) as a barrier and IL-1-treated murine cartilage explants as a chemotactic stimulus for SFs from human tumor necrosis factor-transgenic (hTNFtg) mice. We injected recombinant IL-1 or collagenase into knee joints of wild-type mice, followed by tail vein injection of fluorescence-labeled hTNFtg SFs. The distribution and intensity of transmigrating hTNFtg SFs were measured by fluorescence reflectance imaging with X-ray coregistration. Toluidine blue staining was performed to evaluate the amount of cartilage destruction.. Histomorphometric analyses and in vivo imaging revealed a high degree of cartilage proteoglycan loss after intra-articular IL-1 and collagenase injection, accompanied by an enhanced in vivo extravasation of hTNFtg SFs into the respective knee joints, suggesting that structural cartilage damage contributes significantly to the attraction of hTNFtg SFs into these joints. In vitro results showed that degraded cartilage was directly responsible for the enhanced transmigratory capacity because stimulation with IL-1-treated cartilage, but not with IL-1 or cartilage alone, was required to increase hTNFtg SF migration.. The present data indicate that structural cartilage damage facilitates the migration of arthritic SF into affected joints. The prevention of early inflammatory cartilage damage may therefore help prevent the progression of rheumatoid arthritis and its spread to previously unaffected joints.

Topics: Animals; Arthritis, Rheumatoid; Carbocyanines; Cartilage, Articular; Cell Movement; Cell Tracking; Fibroblasts; Fluorescent Dyes; Humans; Interleukin-1; Knee Joint; Mice, Inbred C57BL; Mice, Transgenic; Synovial Membrane; Time Factors; Tumor Necrosis Factor-alpha

To investigate mitochondrial membrane integrity, lipid peroxidation and cytotoxicity in peripheral lymphocytes (PL) from rheumatoid arthritis (RA) patients.. South African black RA patients (HIV(-)) were recruited into the study. Mitochondrial membrane potential (Deltapsi(m)) was analysed in PL using the JC-1 dye distribution assay and flow cytometry. Correlations between Deltapsi(m) and clinical parameters were tested for statistical significance. Cytotoxicity (LDH) and lipid peroxidation (thiobarbituric acid reactive substances (TBARS)) was also determined.. Our findings show significantly elevated levels of cytotoxicity (p=0.0029) and lipid peroxidation (p=0.0030) in RA. A significantly higher percentage of circulating PL contained depolarised mitochondria (p=0.0003) which correlated with disease activity and C-reactive protein levels in patients. Collapse of Deltapsi(m) also negatively correlated to absolute lymphocyte counts (r=-0.4041; p=0.0197).. These findings suggest a possible role for mitochondrial membrane alterations in the pathology of RA.

Topics: Arthritis, Rheumatoid; Benzimidazoles; Carbocyanines; Humans; L-Lactate Dehydrogenase; Lymphocyte Count; Membrane Potential, Mitochondrial; Oxidative Stress