Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003873 (rheumatoid arthritis)
 53,068 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Osteoprotegerin (OPG), a soluble decoy receptor for receptor activator of nuclear factor kappaB ligand, is implicated in the pathogenesis of atherosclerosis. Patients with rheumatoid arthritis (RA) have inflammation and increased atherosclerosis. We examined the hypothesis that OPG concentrations are increased in patients with RA and are associated with coronary-artery atherosclerosis. Serum OPG concentrations were measured by ELISA and coronary-artery calcification by electron-beam computer tomography in 157 patients with RA and 87 control subjects. OPG concentrations were higher in patients with long-standing RA (n=67) [median (interquartile range)]: [1895 (1337-2847) pg/mL, and early RA (n=90): [1340 (1021-1652) pg/mL, than controls 1068 (692-1434) pg/mL; (p<0.001)]. In patients with RA, OPG concentrations were associated with erythrocyte sedimentation rate (p<0.001), homocysteine (p=0.001), disease duration (p=0.02), coronary calcium score (p=0.03), and cumulative dose of corticosteroids (p=0.04) after adjustment for age and sex. In patients with long-standing RA, OPG was associated with coronary-artery calcification independently of cardiovascular risk factors and disease activity [OR for every increase in 500 pg/mL of OPG=2.22 (1.43-3.34), p<0.001]. In conclusion, OPG concentrations are increased in patients with RA and are associated with inflammation. In patients with long-standing disease, OPG is independently associated with coronary-artery calcification.
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PMID:Serum osteoprotegerin is increased and independently associated with coronary-artery atherosclerosis in patients with rheumatoid arthritis. 1757 Mar 71

Protein expression of osteopontin (OPN), osteoprotegerin (OPG), bone sialoprotein (BSP), osteocalcin (OC), RANKL and PTHrP was determined by use of immunohistochemical analysis on tissue arrays (48 cases of PVNS, 20 cases of active (a-RA), non-active rheumatoid arthritis (na-RA), and osteoarthritis (OA)). Additionally, gene expression was analysed using complimentary DNA (cDNA) microarrays. All PVNS cases showed a higher level of both protein and gene expression of RANKL, OPN and BSP in comparison with OA cases. Expression of OPG was not significantly different in PVNS compared to OA. The RANKL/OPG expression ratio was significantly higher in PVNS than in OA. High expressions level of proteins involved in bone degradation in PVNS may promote an intra-osseous propagation of the lesion. This evidence suggests that PVNS might respond to treatment using specific inhibitors of RANKL, OPN and BSP.
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PMID:High expression level of bone degrading proteins as a possible inducer of osteolytic features in pigmented villonodular synovitis. 1760 61

Receptor activator of nuclear factor XB ligand (RANKL) belongs to the TNF superfamily of cytokines. It plays a key role in osteoclastogenesis, activation, and survival of osteoclasts. The differentiation of macrophage/monocyte-like cells into osteoclasts critically depends on the binding of monocyte-colony stimulating factor (M-CSF) and RANKL by their respective plasma-membrane receptors, c-Fms and RANK. Osteoprotegerin (OPG), a soluble protein of the TNF receptor superfamily that is synthesized mainly by osteoblasts, is a decoy receptor that binds RANKL. In this way OPG competes with RANK what results in the inhibition of osteoclastogenesis and bone resorption. It has been shown that the RANKL/OPG ratio may determine the delicate balance between bone resorption and synthesis. Under normal conditions RANKL is mainly produced by osteoblasts and bone marrow stromal cells. However, in many pathological conditions such as rheumatoid arthritis (RA) and neoplastic osteolysis RANKL is also produced by T and B lymphocytes, macrophages/ monocytes, fibroblasts, synoviocytes, and megakaryocytes. In RA osteolysis is promoted not only by M-CSF and RANKL, but also by other cytokines (TNF, IL-1beta, IL-6, IL-7, IL-11, IL-15, IL-17, IL-18), hormones (PTH, PTH-rP, corticosteroids), and prostaglandin E2. On the contrary, OPG, interferon gamma, IL-4, TGF-beta, bifosfonians, and estrogens inhibit RA-associated osteoclastogenesis. Recently, therapeutics for pathological bone destruction targeting RANKL pathways have been used for the treatment of postmenopausal osteoporosis.
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PMID:[Role of tumor necrosis factor family ligands in the pathogenesis of rheumatoid arthritis--new therapeutical opportunities]. 1768 31

We examined associations between human leukocyte antigen DRB1 (HLA-DRB1) shared epitope (SE), receptor activator of nuclear factor-kappaB (RANK), RANK ligand (RANKL), osteoprotegerin (OPG), and interleukin 17 (IL-17) genotypes with age of disease onset and radiographic progression in Japanese patients with early rheumatoid arthritis (RA). HLA-DRB1 genotypes were evaluated in 123 patients with early RA (98 female, 25 male) within 1 year of symptom onset. In 72 patients, radiographic progression over a 2-year period was evaluated using Larsen's methods, and genotypes of three polymorphic sites in RANK, five sites in RANKL, two sites in OPG, and three sites in IL-17 were determined by direct polymerase chain reaction sequencing. Possession of an SE allele was significantly associated with earlier disease onset in females (median 46.9 vs 51.9 years in SE- patients; P = 0.04). Single nucleotide polymorphisms (SNPs) in RANKL (rs2277438, P = 0.028) and IL-17 (rs3804513, P = 0.049) were significantly associated with radiographic progression at 2 years. RANKL-G-, SE- patients (n = 12) had significantly less joint damage than did RANKL-G+, SE- patients (n = 11; P = 0.0038), RANKL-G-, SE+ patients (n = 21; P = 0.0018) and RANKL-G+, SE+ patients (n = 28; P = 0.0024). In Japanese RA patients, HLA-DRB1 SE alleles are associated with disease onset at an earlier age, as has been observed in Caucasian RA patients. In addition, SNPs in RANKL and IL-17 may be associated with radiographic progression in Japanese patients with early RA.
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PMID:Associations between HLA-DRB1, RANK, RANKL, OPG, and IL-17 genotypes and disease severity phenotypes in Japanese patients with early rheumatoid arthritis. 1787 45

This study demonstrates that IL-23 stimulates the differentiation of human osteoclasts from peripheral blood mononuclear cells (PBMC). Furthermore, in vivo blockade of endogenous IL-23 activity by treatment with anti-IL-23 antibody attenuates collagen-induced arthritis in rats by preventing both inflammation and bone destruction. IL-23 induced human osteoclastogenesis in cultures of PBMC in the absence of osteoblasts or exogenous soluble-receptor activator of NF-kappaB ligand (RANKL). This IL-23-induced osteoclastogenesis was inhibited by osteoprotegerin, anti-IL-17 antibody, and etanercept, suggesting that RANKL, IL-17, and TNF-alpha are involved. In addition, we found the ratio of production levels of IL-17 to those of IFN-gamma from activated human T cells was elevated at 1 to 10 ng/ml IL-23. The inductive effect of IL-17 and the inhibitory effect of IFN-gamma on osteoclastogenesis indicate that the balance of these two cytokines is particularly important. We also demonstrated that IL-23 administered at a later stage significantly reduced paw volume in rats with collagen-induced arthritis, in a dose-dependent manner. Furthermore, anti-IL-23 antibody reduced synovial tissue inflammation and bone destruction in these rats. These findings suggest that IL-23 is important in human osteoclastogenesis and that neutralizing IL-23 after onset of collagen-induced arthritis has therapeutic potential. Thus, controlling IL-23 production and function could be a strategy for preventing inflammation and bone destruction in patients with rheumatoid arthritis.
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PMID:IL-23 induces human osteoclastogenesis via IL-17 in vitro, and anti-IL-23 antibody attenuates collagen-induced arthritis in rats. 1788 76

Inhibition of NF-kappaB is known to be effective in reducing both inflammation and bone destruction in animal models of arthritis. Our previous study demonstrated that a small cell-permeable NF-kappaB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), suppresses expression of proinflammatory cytokines and ameliorates mouse arthritis. It remained unclear, however, whether DHMEQ directly affects osteoclast precursor cells to suppress their differentiation to mature osteoclasts in vivo. The effect of DHMEQ on human osteoclastogenesis also remained elusive. In the present study, we therefore examined the effect of DHMEQ on osteoclastogenesis using a mouse collagen-induced arthritis model, and using culture systems of fibroblast-like synovial cells obtained from patients with rheumatoid arthritis, and of osteoclast precursor cells from peripheral blood of healthy volunteers. DHMEQ significantly suppressed formation of osteoclasts in arthritic joints, and also suppressed expression of NFATc1 along the inner surfaces of bone lacunae and the eroded bone surface, while serum levels of soluble receptor activator of NF-kappaB ligand (RANKL), osteoprotegerin and macrophage colony-stimulating factor were not affected by the treatment. DHMEQ also did not suppress spontaneous expression of RANKL nor of macrophage colony-stimulating factor in culture of fibroblast-like synovial cells obtained from patients with rheumatoid arthritis. These results suggest that DHMEQ suppresses osteoclastogenesis in vivo, through downregulation of NFATc1 expression, without significantly affecting expression of upstream molecules of the RANKL/receptor activator of NF-kappaB/osteoprotegerin cascade, at least in our experimental condition. Furthermore, in the presence of RANKL and macrophage colony-stimulating factor, differentiation and activation of human osteoclasts were also suppressed by DHMEQ, suggesting the possibility of future application of NF-kappaB inhibitors to rheumatoid arthritis therapy.
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PMID:NF-kappaB inhibitor dehydroxymethylepoxyquinomicin suppresses osteoclastogenesis and expression of NFATc1 in mouse arthritis without affecting expression of RANKL, osteoprotegerin or macrophage colony-stimulating factor. 1789

RANK ligand (RANKL) is a key mediator of osteoclast formation, function, and survival. Therefore, RANKL is thought to be responsible for osteoclast-mediated bone resorption in a broad range of disorders such as postmenopausal osteoporosis and cancer-induced bone disease. Moreover, RANKL has been implicated as a primary mediator of bone erosions, a hallmark of rheumatoid arthritis (RA). Denosumab is a fully human monoclonal antibody. This antibody binds to RANKL with high affinity and specificity, and inhibits RANKL-RANK interaction, mimicking the endogenous effects of osteoprotegerin (OPG), a soluble RANKL decoy receptor. Clinical trial data support the continued development of denosumab for the inhibition of bone erosions in RA.
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PMID:[RANKL inhibition as therapy for joint damage]. 1798 81

Osteoclasts and osteoblasts dictate skeletal mass, structure, and strength via their respective roles in resorbing and forming bone. Bone remodeling is a spatially coordinated lifelong process whereby old bone is removed by osteoclasts and replaced by bone-forming osteoblasts. The refilling of resorption cavities is incomplete in many pathological states, which leads to a net loss of bone mass with each remodeling cycle. Postmenopausal osteoporosis and other conditions are associated with an increased rate of bone remodeling, which leads to accelerated bone loss and increased risk of fracture. Bone resorption is dependent on a cytokine known as RANKL (receptor activator of nuclear factor kappaB ligand), a TNF family member that is essential for osteoclast formation, activity, and survival in normal and pathological states of bone remodeling. The catabolic effects of RANKL are prevented by osteoprotegerin (OPG), a TNF receptor family member that binds RANKL and thereby prevents activation of its single cognate receptor called RANK. Osteoclast activity is likely to depend, at least in part, on the relative balance of RANKL and OPG. Studies in numerous animal models of bone disease show that RANKL inhibition leads to marked suppression of bone resorption and increases in cortical and cancellous bone volume, density, and strength. RANKL inhibitors also prevent focal bone loss that occurs in animal models of rheumatoid arthritis and bone metastasis. Clinical trials are exploring the effects of denosumab, a fully human anti-RANKL antibody, on bone loss in patients with osteoporosis, bone metastasis, myeloma, and rheumatoid arthritis.
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PMID:Receptor activator of nuclear factor kappaB ligand and osteoprotegerin regulation of bone remodeling in health and disease. 1805 40

To investigate histological evidence of bone remodeling in response to infliximab for rheumatoid arthritis (RA), bone marrow tissues were extracted from ten RA patients at the time of total knee arthroplasty after treatment of infliximab for an average of 16 months (range, 8-24 months). The patients had a mean age of 65.3 years (range, 57-76 years) with 4.8 mg/week of methotrexate (MTX; 4-6 mg) and 3.8 mg/day of prednisolone (2-5 mg). Control samples were obtained from ten RA patients who did not undergo infliximab therapy. These patients had an average age of 67.6 years (range, 59-78 years) and received 5.2 mg/week of MTX (4-6 mg) and 4.0 mg/day of prednisolone (2-5 mg). Histological examination of structural differences between the infliximab and control groups in bone marrow was performed using hematoxylin and eosin (H & E) to evaluate differences. In immunohistochemical examination, the expressions of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), receptor activator of nuclear (kappa) B ligand (RANKL), osteoprotegerin (OPG), and osteopontin (OPN) were compared between both groups. H & E staining revealed that the bone marrow tissues of the RA patients who underwent infliximab therapy demonstrated newly formed thickness of interstitial septum among the trabeculae as compared with the control group. Moreover, immunohistochemical examinations revealed that TNF-alpha, IL-6, RANKL, OPG, and OPN were expressed in this newly formed bone after infliximab therapy. Therefore, treatment with infliximab improved the histological changes with respect to bone metabolism in the newly formed bone marrow tissues.
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PMID:Histological changes in bone marrow after treatment of infliximab for rheumatoid arthritis. 1806 Mar 42

To elucidate the role of the synovium in bone destruction by osteoclasts in rheumatoid arthritis (RA), primary synovial cells isolated from RA patients were cultured and characterized. The cultured primary cells did not produce RANKL (TRANCE/ODF/OPGL/TNFSF11/CD254), an inducer of osteoclast differentiation, but constitutively produced its inhibitor, osteoprotegerin (OPG). Addition of TNF-alpha to the primary cultures of synovial cells reduced the cell viability and strongly suppressed OPG production. We then established nine synovial cell clones, including SYM-1, responsible for OPG production from primary synovial cell cultures. TNF-alpha induced apoptosis of SYM-1 cells within 24h and decreased OPG levels, while infliximab, a chimerical form of the anti-TNF-alpha antibody drug, suppressed the apoptosis and restored OPG levels. These results suggest the existence of fibroblastic cells producing OPG in the synovium, while TNF-alpha suppresses OPG production by inducing apoptosis in those cells. Further, infliximab is considered to inhibit bone destruction through restoration of OPG levels in RA.
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PMID:Characterization of synovial cell clones isolated from rheumatoid arthritis patients: possible involvement of TNF-alpha in reduction of osteoprotegerin in synovium. 1808 42


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