The aim of this study was to investigate the expression and localization of cyclooxygenase-1 and -2 (COX-1 and COX-2) in synovial tissues from patients with rheumatoid arthritis (RA). Synovial tissues from 9 patients with RA and 5 patients with osteoarthritis (OA) were examined for COX-1 and COX-2 expressions by immunohistochemical staining using 2 polydonal COX-1 and COX-2 antibodies. In RA synovia, synovial lining cells showed intense immunostaining for COX-1, whereas slight to moderate staining was observed in inflammatory cells, stromal fibroblast-like cells and vascular endothelial cells. There was no significant difference in COX-1 expression between RA and OA synovia. The localization of COX-2 expression dearly differed from that of COX-1 expression, being most intense in inflammatory cells. However, there was no difference in COX-1 and COX-2 expressions between RA and OA synovial tissues. Our observations support that inflammatory mechanisms modulated by COX-1 and COX-2 in chronic RA synovium might be similar to those in chronic OA synovium.
Adult ; Aged ; Arthritis, Rheumatoid/pathology ; Arthritis, Rheumatoid/enzymology* ; Cell Division ; Female ; Fibrin/metabolism ; Human ; Isoenzymes/metabolism ; Isoenzymes/biosynthesis* ; Male ; Middle Age ; Neutrophil Infiltration ; Osteoarthritis/enzymology ; Prostaglandin-Endoperoxide Synthase/metabolism ; Prostaglandin-Endoperoxide Synthase/biosynthesis* ; Stromal Cells/pathology ; Stromal Cells/enzymology ; Synovial Membrane/pathology ; Synovial Membrane/enzymology*

Oxidative stress such as reactive oxygen species (ROS) within the inflamed joint have been indicated as being involved as inflammatory mediators in the induction of arthritis. Correlations between extracellular-superoxide dismutase (EC-SOD) and inflammatory arthritis have been shown in several animal models of RA. However, there is a question whether the over-expression of EC-SOD on arthritic joint also could suppress the progression of disease or not. In the present study, the effect on the synovial tissue of experimental arthritis was investigated using EC-SOD over-expressing transgenic mice. The over-expression of EC-SOD in joint tissue was confirmed by RT-PCR and immunohistochemistry. The degree of the inflammation in EC-SOD transgenic mice was suppressed in the collagen-induced arthritis model. In a cytokine assay, the production of pro-inflammatory cytokines such as, IL-1beta, TNFalpha, and matrix metalloproteinases (MMPs) was decreased in fibroblast-like synoviocyte (FLS) but not in peripheral blood. Histological examination also showed repressed cartilage destruction and bone in EC-SOD transgenic mice. In conclusion, these data suggest that the over-expression of EC-SOD in FLS contributes to the activation of FLS and protection from joint destruction by depressing the production of the pro-inflammatory cytokines and MMPs. These results provide EC-SOD transgenic mice with a useful animal model for inflammatory arthritis research.
Animals ; Arthritis, Experimental/blood/*enzymology/metabolism ; *Arthritis, Rheumatoid/enzymology/pathology ; Fibroblasts/metabolism ; Gene Expression Regulation ; Inflammation/pathology ; Interleukin-1beta/blood/metabolism ; Joints/enzymology/pathology ; Matrix Metalloproteinases/blood/metabolism ; Mice ; Mice, Transgenic ; Reactive Oxygen Species/metabolism ; *Superoxide Dismutase/genetics/metabolism ; Synovial Fluid/*enzymology ; Synovial Membrane/pathology

Activation of caspase-1 by NALP3 inflammasomes has been shown to be important in initiating acute gouty arthritis. The objectives of this study were to measure the levels of caspase-1 in synovial fluid in gout and various arthritides, and to elucidate the clinical significance of caspase-1 levels in synovial fluid. Caspase-1, IL-1beta, IL-18, and uric acid were measured in synovial fluid from 112 patients with gout and other arthritides, such as rheumatoid arthritis, osteoarthritis, and spondyloarthropathy. Caspase-1 in synovial fluid from patients with crystal-induced arthritis, inflammatory arthritis, osteoarthritis, and spondyloarthropathy was 35.9 +/- 86.7, 49.7 +/- 107.7, 2.1 +/- 7.0, and 152.6 +/- 155.7 pg/mL, respectively. The mean level and the frequency of high levels (> or =125 pg/mL) of caspase-1 in spondyloarthropathy were significantly higher than those in the other arthritides including gout. Caspase-1 was detectible in the synovial fluid of patients with the various arthritides. Contrary to our hypothesis, the caspase-1 level in the synovial fluid of patients with gout was not higher than in that of other arthritides. High levels of caspase-1 may be helpful in differentiating spondyloarthropathy from other arthritides.
Adult ; Aged ; Arthritis, Rheumatoid/enzymology/metabolism/pathology ; Caspase 1/*analysis ; Female ; Gout/*enzymology/metabolism/pathology ; Humans ; Interleukin-18/analysis ; Interleukin-1beta/analysis ; Leukocyte Count ; Male ; Middle Aged ; Osteoarthritis/enzymology/metabolism/pathology ; Spondylarthropathies/*enzymology/metabolism/pathology ; Synovial Fluid/*enzymology/metabolism ; Uric Acid/analysis

Macrophage activation syndrome (MAS) is a rare and potentially fatal complication of rheumatic disorders in children. We describe a 13-month-old boy in whom MAS developed as a complication of systemic juvenile rheumatoid arthritis (S-JRA). He suffered from fever and generalized rash followed by multiple joints swelling for four months before admission. Physical examination revealed cervical lymphadenopathy and hepatosplenomegaly. Laboratory findings were: abnormal liver enzymes, increased triglyceride and ferritin levels, coagulopathies resembling disseminated intravascular coagulation, anemia and thrombocytopenia. Hyperplasia of hemophagocytic macrophages was remarkable in his bone marrow. Methylprednisolone and cyclosporin therapy resulted in clinical and laboratory improvements. This is the third case of MAS associated with S-JRA in Koreans, and the first one, in which hemophagocytic macrophages were proven in bone marrow.
Alanine Transaminase/metabolism ; Alkaline Phosphatase/metabolism ; Antigens, CD/blood ; Antigens, Differentiation, Myelomonocytic/blood ; Arthritis, Juvenile Rheumatoid/blood/*complications/pathology ; Aspartate Aminotransferases/metabolism ; Blood Cell Count ; Hepatomegaly/*etiology/pathology ; Humans ; Infant ; Liver/enzymology/pathology ; *Macrophage Activation ; Male ; Partial Thromboplastin Time ; Prothrombin Time ; Splenomegaly/*etiology/pathology ; Syndrome ; gamma-Glutamyltransferase/metabolism

AIMTo study the effects of lipopolysaccharide (LPS), the supernatant of U937 cells stimulated with LPS and dexamethasone on matrix metalloproteinase-9 (MMP-9) expression in the synoviocyte from patients with rheumatoid arthritis(RA).

METHODSFibroblast-like cells (FLS) from the joint tissue of patients with rheumatoid arthritis were cultured and incubated for 24 h with LPS (1 mg.L-1) or the supernatant of U937 cells stimulated with LPS (1 mg.L-1) for 24 h. Dexamethasone was added to the supernatant of U937 cells and FLS was incubated for 24 h. The activity of MMP-9 was analyzed by gelatin zymography. Protein expression of MMP-9 was detected by Western blot using special polyclonal antibodies. The mRNA expression of MMP-9 was detected by RT-PCR.

RESULTSThe expression of MMP-9 was not markedly changed in FLS treated with LPS. The MMP-9 activity, MMP-9 secretion and MMP-9 mRNA expression were significantly increased in FLS cultured with the supernatant from U937 cell treated with LPS. Dexamethasone markedly inhibited the activity, protein secretion and mRNA expression of MMP-9 in FLS cultured with the supernatant from U937 cell stimulated with LPS, and the inhibitory effects were increased as the concentration of dexamethasone increased.

CONCLUSIONLPS did not directly affect the expression of MMP-9 in FLS, but it was found to indirectly cause the increase of MMP-9 expression in FLS by stimulating U937 cell. Dexamethasone was found to inhibit this increase of MMP-9 expression.

Anti-Inflammatory Agents ; pharmacology ; Arthritis, Rheumatoid ; pathology ; Cell Division ; drug effects ; Cells, Cultured ; Dexamethasone ; pharmacology ; Fibroblasts ; pathology ; Gene Expression ; drug effects ; Humans ; Lipopolysaccharides ; pharmacology ; Matrix Metalloproteinase 9 ; biosynthesis ; genetics ; metabolism ; RNA, Messenger ; drug effects ; genetics ; Synovial Membrane ; drug effects ; enzymology ; pathology ; U937 Cells

Triptolide (TPT), an active compound extracted from Chinese herb Tripterygium wilfordii , has been used in therapy of rheumatoid arthritis (RA). In this study, after synovial fibroblasts from rheumatoid arthritis (RASFs) were treated with TPT, we investigated its effect on the differentiation of Th17 cells. Firstly, the mRNA level of cyclooxygenase (COX) wad detected by qRT-PCR and the protein level of prostaglandin E2 (PGE2) was tested by ELISA in RASFs treated with different concentrations (0, 10, 50, 100 nmol L-1 ) of TPT. Then after TPT pre-treated RASFs and RA CD4 + T cells wer e co-cultured for 3 days in the presence or absence of PGE2, IL-17 and IFN-gamma production in CD4 T cell subsets were detected by flow cytometry. The results showed TPT decreased the mRNA experssion of COX2 and the secretion of PGE2 in RASFs in a dose-dependent manner(P <0. 05). We further found that differentiation of Thl7 cells was downregulated in a dose-dependent manner, and exogenous PGE2 could reverse the inhibition of Th17 cell differentiation(P <0. 05). Taken together, our results demonstrated that TPT inhibited the mRNA level of COX2 and the secretion of PGE2 in RASFs, which partly led to impaired Th17 cell differentiation in vitro.
Arthritis, Rheumatoid ; drug therapy ; enzymology ; immunology ; Cell Differentiation ; drug effects ; Cell Line ; Cyclooxygenase 2 ; genetics ; metabolism ; Dinoprostone ; metabolism ; Diterpenes ; pharmacology ; Epoxy Compounds ; pharmacology ; Fibroblasts ; drug effects ; immunology ; Gene Expression Regulation, Enzymologic ; drug effects ; Humans ; Middle Aged ; Phenanthrenes ; pharmacology ; Synovial Fluid ; drug effects ; Th17 Cells ; drug effects ; pathology