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

Oncostatin M (OSM), a member of the IL-6 superfamily of cytokines, is elevated in patients with rheumatoid arthritis and, in synergy with IL-1, promotes cartilage degeneration by matrix metalloproteinases (MMPs). We have previously shown that OSM induces MMP and tissue inhibitor of metalloproteinase-3 (TIMP-3) gene expression in chondrocytes by protein tyrosine kinase-dependent mechanisms. In the present study, we investigated signaling pathways regulating the induction of MMP and TIMP-3 genes by OSM. We demonstrate that OSM rapidly stimulated phosphorylation of Janus kinase (JAK) 1, JAK2, JAK3, and STAT1 as well as extracellular signal-regulated kinase (ERK) 1/2, p38, and c-Jun N-terminal kinase 1/2 mitogen-activated protein kinases in primary bovine and human chondrocytes. A JAK3-specific inhibitor blocked OSM-stimulated STAT1 tyrosine phosphorylation, DNA-binding activity of STAT1 as well as collagenase-1 (MMP-1), stromelysin-1 (MMP-3), collagenase-3 (MMP-13), and TIMP-3 RNA expression. In contrast, a JAK2-specific inhibitor, AG490, had no impact on these events. OSM-induced ERK1/2 activation was also not affected by these inhibitors. Similarly, curcumin (diferuloylmethane), an anti-inflammatory agent, suppressed OSM-stimulated STAT1 phosphorylation, DNA-binding activity of STAT1, and c-Jun N-terminal kinase activation without affecting JAK1, JAK2, JAK3, ERK1/2, and p38 phosphorylation. Curcumin also inhibited OSM-induced MMP-1, MMP-3, MMP-13, and TIMP-3 gene expression. Thus, OSM induces MMP and TIMP-3 genes in chondrocytes by activating JAK/STAT and mitogen-activated protein kinase signaling cascades, and interference with these pathways may be a useful approach to block the catabolic actions of OSM.
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PMID:Oncostatin M-induced matrix metalloproteinase and tissue inhibitor of metalloproteinase-3 genes expression in chondrocytes requires Janus kinase/STAT signaling pathway. 1120 8

In an effort to elucidate the role of mechanical stimuli in rheumatoid arthritis, we determined mRNA levels of matrix metalloproteinase (MMP)-1, MMP-3, MMP-13, tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2, and three transcription factors (c-fos, ets-1, and ets-2) under two mechanical shearing conditions as well as simulated unloading. Human synovial cell cultures (MH7A and RA99-01), derived from rheumatoid arthritis patients, were grown for 1 h under mechanical stimuli and the transcript level was assayed by the reverse transcription-polymerase-chain reaction procedure. First, gentle shearing, estimated at approximately 1 dyn/cm(2), induced a consistent decrease in mRNA level of MMP-1, MMP-3, MMP-13, and ets-1 and an increase in the transcript level of TIMP-1, TIMP-2, c-fos, and ets-2. Second, intermediate shearing, estimated at approximately 6 dyn/cm(2), elevated the mRNA level of all MMPs, TIMPs, and the three transcription factors. Third, minimum mRNA level of c-fos, ets-1, and ets-2 was achieved under control conditions at rest, gentle shearing, and simulated unloading, respectively. These in vitro results support a stimulus-dependent transcriptional regulation of MMPs, TIMPs, and transcription factors in cell cultures, suggesting a potential role of shear stress in tissue degradation and prevention in rheumatic joints.
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PMID:Messenger-RNA expression of matrix metalloproteinases, tissue inhibitors of metalloproteinases, and transcription factors in rheumatic synovial cells under mechanical stimuli. 1124 61

The major pathologic manifestations of rheumatoid arthritis (RA) and osteoarthritis (OA) are joint inflammation and articular cartilage resorption by proinflammatory cytokine-stimulated matrix metalloproteinases (MMPs) and aggrecanases. The Chinese herbal remedy Tripterygium wilfordii Hook F (TWHF) is effective for treatment of various types of arthritis. However, mechanisms and targets of its actions are poorly understood. Anti-inflammatory activities of the extracts of this plant were previously attributed to inhibition of cyclooxygenase-2 mRNA and prostaglandin E(2) synthesis. Here, we show that in primary human femoral head osteoarthritic and normal bovine chondrocytes, TWHF partially or completely inhibited mRNA and protein expression of tumor necrosis factor-alpha, interleukin (IL)-1, and IL-17-inducible MMP-3 and MMP-13. This agent also inhibited cytokine-stimulated MMP-3 protein expression in human synovial fibroblasts. A dose range of 2.5 to 10 ng/ml of TWHF was effectively inhibitory for IL-1. Pretreatment for 30 min or 1 h (but not 2-10 h) after IL-1 treatment with TWHF inhibited MMP-3 RNA induction. The inhibitory doses had no adverse effect on the viability of chondrocytes. Mechanistic studies revealed no impact on the activation of extracellular signal-regulated kinase, p38, and c-Jun N-terminal kinase mitogen-activated protein kinases. Instead, TWHF partially inhibited DNA binding capacity of cytokine-stimulated activating protein-1 (AP-1) and nuclear factor-kappaB (NF-kappaB) transcription factors. Therefore, besides its anti-inflammatory activity, this agent may also be effective in blocking cartilage matrix resorption by MMPs by impairing AP-1 and NF-kappaB binding activities. Thus, TWHF extract contains novel inhibitors of MMP expression that may be of therapeutic potential in arthritis and other conditions associated with increased MMPs.
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PMID:Tripterygium wilfordii Hook F extract suppresses proinflammatory cytokine-induced expression of matrix metalloproteinase genes in articular chondrocytes by inhibiting activating protein-1 and nuclear factor-kappaB activities. 1130 4

In an effort to elucidate the interplay between mechanical load and proteolytic gene expression in arthritic tissue degradation, we investigated cellular morphology and mRNA levels of matrix metalloproteinase-13 (MMP-13) genes under mechanical stress in human MH7A synovial cells. The cells were isolated from the knee joint of a rheumatoid arthritis patient. Using a reverse transcription-polymerase chain reaction procedure, we found that loading by an oscillatory shaker transiently decreased the level of MMP-13 mRNA and unloading by a clinostat increased its mRNA level. The unloaded cells appeared to be rounded and displayed a poorly developed track of peripheral fibers, whereas the cells under loading tended to align to the shear flow and were elongated. We also found that altering the oscillatory direction of mechanical loads contributed to a further reduction in mRNA expression of MMP-13. Our results demonstrate the role of mechanical loading and unloading in the transcriptional regulation of MMP-13 in synovial cells, and suggest the potential value of physical therapy for arthritic joints.
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PMID:Altered mRNA level of matrix metalloproteinase-13 in MH7A synovial cells under mechanical loading and unloading. 1133 20

Rheumatoid arthritis (RA) and osteoarthritis are chronic diseases that result in cartilage degradation and loss of joint function. Currently available drugs are predominantly directed towards the control of pain and/or the inflammation associated with joint synovitis but they do little to reduce joint destruction. In the future, it will be important to have drugs that prevent the structural damage caused by bone and cartilage breakdown. In this review, we will outline the structure and function of cartilage and the key features of matrix metalloproteinases (MMPs), enzymes involved in joint destruction. We will present evidence for the role of MMPs in RA and osteoarthritis, and describe the potential of synthetic inhibitors to control MMP activity and so prevent joint destruction. MMPs are able to cleave all components of the cartilage matrix. Regulation of MMPs is aberrant in osteoarthritis and RA, and MMPs have been implicated in the collagen breakdown that contributes to joint destruction in these diseases. Synthetic MMP inhibitors have been developed. In animal models of osteoarthritis and/or RA, these agents have shown chondroprotective effects. However, results from clinical trials in RA have been equivocal, with some studies being terminated because of lack of efficacy or safety concerns. Nevertheless, this approach remains promising. Increased understanding of the structure, regulation and function of individual MMPs may lead to more effective strategies, and approaches aimed at multiple steps of the pathogenesis of arthritis may be needed to break the chronic cycle of joint destruction.
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PMID:The clinical potential of matrix metalloproteinase inhibitors in the rheumatic disorders. 1134 30

Although a considerable amount of effort has been placed on discovering the etiologies of cancer, the majority of the basic cancer research existing today has focused on understanding the molecular mechanism of tumor formation and metastasis. Metastatic spread of tumors continues to be a major obstacle to successful treatment of malignant tumors. Approximately 30% of those patients diagnosed with a solid tumor have a clinically detectable metastasis and for the remaining 70%, metastases are continually being formed throughout the life of the tumor. Even after the tumor is excised, the threat of death is attributable to the metastasis that may occur through the remaining tumor cells. In addition, treating the metastasis often proves futile since metastasis often vary in size, composition, and anatomical location. New treatments blocking the formation of metastasis will provide greater chances of survival for cancer patients. One family of enzymes that has been shown over the years to play a role in tumor progression is the matrix metalloproteinase (MMP) family. The main function of MMPs, also known as matrixins, is degradation of the extracellular matrix physiologic function involving MMPs include wound healing, bone resorption and mammary involution. MMPs, however, also contribute to pathological conditions including rheumatoid arthritis, coronary artery disease, and cancer. Tumor cells are believed to utilize the matrix degrading capability of these enzymes to spread to distant sites. In addition, MMPs also are thought to promote the growth of these tumor cells once they have metastasized. This review will discuss the role of MMPs and their inhibitors in tumor invasion, angiogenesis and metastasis with special emphasis on the gelatinases, MMP-2 and MMP-9.
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PMID:The role of matrix metalloproteinases in tumor angiogenesis and tumor metastasis. 1134 15

To assess the role of bone marrow in the pathogenesis of rheumatoid arthritis (RA), we examined the capacity of CD34(+) cells from bone marrow to generate fibroblast-like type B synoviocytes. CD34(+) cells from the bone marrow of 22 RA patients differentiated into cells with fibroblast-like morphology, which expressed prolyl 4-hydroxylase, in the presence of stem cell factor (SCF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor alpha (TNF-alpha), much more effectively than CD34(+) cells from bone marrow of 15 control subjects (10 patients with osteoarthritis and 5 healthy individuals). The generation of fibroblast-like cells was not at all observed in cultures with SCF, GM-CSF, and interleukin 4 (IL-4) with or without TNF-alpha. Generation of fibroblast-like cells was correlated with matrix metalloproteinase (MMP)-1 levels in culture supernatants. Thus, MMP-1 levels were significantly higher in TNF-alpha-stimulated cultures of bone marrow CD34(+) cells from patients with RA than in those from the control group. These results indicate that bone marrow CD34(+) cells from patients with RA have abnormal capacities to respond to TNF-alpha and to differentiate into fibroblast-like cells producing MMP-1, suggesting that bone marrow CD34(+) progenitor cells might generate type B synoviocytes and thus could play an important role in the pathogenesis of RA.
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PMID:Induction of fibroblast-like cells from CD34(+) progenitor cells of the bone marrow in rheumatoid arthritis. 1152 91

Membrane-type 1 matrix metalloproteinase (MT1-MMP) is thought to be a putative regulator of pro-gelatinase A (MMP-2) in the rheumatoid synovium. In this study, we examined the effects of IL-1beta, one of the inflammatory cytokines, on the expression of MT1-MMP and the activation of pro-MMP-2 using rheumatoid synovial cells. We also studied the effects of KE-298 (2-acetylthiomethyl-4-(4-methylphenyl)-4-oxobutanoic acid), a new disease-modifying anti-rheumatic drug (DMARD), on MT1-MMP expression of rheumatoid synovial cells. Type B synovial cells (fibroblast-like synovial cells) were cultured with KE-298 (25-100 microg/ml) in the presence of IL-1beta for 48 h. Activation of pro-MMP-2 secreted from synovial cells was analysed by gelatin zymography. Reverse transcription-polymerase chain reaction (RT-PCR) methods were used to detect MT1-MMP mRNA. MT1-MMP protein expression on synovial cells was examined by anti-MT1-MMP immunoblot. An active form of MMP-2 was demonstrated in the culture media conditioned by IL-1beta-stimulated synovial cells. In addition, MT1-MMP mRNA and protein expression of rheumatoid synovial cells were increased by IL-1beta treatment. KE-298 blocked this IL-1beta-induced pro-MMP-2 activation and MT1-MMP expression, but did not affect IL-1beta-induced tissue inhibitor of metalloproteinase-2 (TIMP-2) secretion from rheumatoid synovial cells. These findings indicate that activation of rheumatoid synovial cells by IL-1beta results in the induction of MT1-MMP expression. Given that MT1-MMP promotes matrix degradation by activating pro-MMP-2, these results suggest a novel mechanism whereby cytokine may contribute to articular destruction in rheumatoid arthritis (RA). KE-298 may prevent this process by down-regulating MT1-MMP expression.
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PMID:Expression of membrane-type 1 matrix metalloproteinase in rheumatoid synovial cells. 1167 9

Etanercept (Enbrel; Wyeth-Ayerst/Immunex Inc, Seattle, WA, USA) is a subcutaneously administered novel fusion protein consisting of the extracellular ligand-binding domain of the 75 kD receptor for tumor necrosis factor-alpha (anti-TNFalpha) and the Fc portion of human IgG1. The agent is synthesized by plasmid transfection of a Chinese hamster ovary cell line, utilizing recombinant DNA technology. Etanercept was approved by the US FDA for treatment of multi-drug resistant rheumatoid arthritis in 1998, but no human data exist regarding the impact of anti-TNFalpha therapy on human reproductive function or its use before ovulation induction. As TNFalpha potentiates collagenolysis via matrix metalloproteinase gene expression (thereby facilitating ovulation), there exists a theoretical risk that TNFalpha-inhibition could exert an undesirable effect on ovulation and pregnancy. In this report, we describe the first case of ovulation induction, intrauterine insemination, normal pregnancy and singleton delivery of a healthy infant following chronic ( > 1 year) pre-ovulatory TNFalpha-inhibitor therapy for rheumatoid arthritis. Reproductive endocrinologists and obstetrician-gynecologists should be familiar with etanercept therapy in the context of severe rheumatic disease, and offer appropriate reassurance regarding its safe use for infertility patients planning ovulation induction.
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PMID:Successful ovulation induction, conception, and normal delivery after chronic therapy with etanercept: a recombinant fusion anti-cytokine treatment for rheumatoid arthritis. 1171 66

Recent work has established that IL-1beta plays a central role in the inflammation and connective tissue destruction observed in both rheumatoid arthritis and osteoarthritis. These processes result from the ability of this inflammatory cytokine to activate expression of genes for neutral proteases, such as the matrix metalloproteinases. While IL-1beta activates matrix metalloproteinase genes within several hours, it also activates immediate early genes, which are required for the later expression of matrix metalloproteinases and other arthritis-perpetuating genes, are also activated. To identify putative immediate early genes involved in IL-1beta-mediated arthritic disease, a chondrocytic cell line (SW1353) was stimulated with this cytokine for 2 hours, total RNA was isolated, and expressed genes were identified by microarray analysis. This analysis identified alterations in the expression of multiple transcription factors, cytokines, growth factors and their receptors, adhesion molecules, proteases, and signaling intermediates that may contribute to inflammation and cartilage destruction in arthritis. Interestingly, confirmation of the expression of activating protein-1 family members by reverse transcriptase polymerase chain reaction revealed a preferential increase in junB, a known transcriptional antagonist of c-jun. The failure to observe induction of early growth response gene-1, which was detected by reverse transcriptase polymerase chain reaction to be substantially and transiently induced by 1 hour of IL-1 treatment, may be explained by the known instability of the message after early induction. However, this analysis has identified numerous IL-1beta-responsive genes that warrant further investigation as mediators of disease in arthritis.
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PMID:Early response genes induced in chondrocytes stimulated with the inflammatory cytokine interleukin-1beta. 1171 93


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