Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003864 (arthritis)
 69,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The distribution of the matrix metalloproteinases, collagenase, stromelysin, gelatinases A and B, and the tissue inhibitor of metalloproteinases in cartilage and synovium removed from rabbits up to 27 days after induction of two models of arthritis was investigated by immunolocalization. Following intra-articular injection of poly-D-lysine/hyaluronic acid coacervate, collagenase and stromelysin were found bound to cartilage matrix, but there was little increase in chondrocyte synthesis of these enzymes. The synovium underwent a complex wound healing response involving invagination and encapsulation of the coacervate and inflammatory cell debris, during which all four metalloproteinases and tissue inhibitor of metalloproteinase could be immunolocalized. The second model, intra-articular injection of ovalbumin into sensitized rabbits, caused considerable chondrocyte necrosis; collagenase was found bound to cartilage matrix on day 13, although again there was little evidence of synthesis by chondrocytes. Inflammatory cell infiltration of meniscoid synovia took place initially, followed by fibrosis involving macrophagelike cells secreting gelatinase A. In both models there was rapid loss of glycosaminoglycan metachromasia from the cartilage matrix. These results are discussed in relation to current knowledge of metalloproteinase involvement in the chronic rheumatoid synovial pannus erosion of cartilage in humans. The data suggest that there are considerable differences between rheumatoid arthritis and these models, and their use must therefore be carefully defined.
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PMID:Rabbit models of arthritis: immunolocalization of matrix metalloproteinases and tissue inhibitor of metalloproteinase in synovium and cartilage. 834 6

Articular chondrocytes from rheumatoid joints have been shown to express class II major histocompatibility (MHC) antigens that were correlated with the presence of interferon-gamma (IFN-gamma) in the inflamed joint. Chondrocytes expressing MHC antigens function as antigen presenting cells and thus stimulate lymphocyte proliferation. These responses suggest a powerful role for the IFN-gamma stimulation of chondrocytes. The present studies were designed to examine the functional role of chondrocytes exposed to IFN-gamma during cartilage degradation that occurs in synovial disease. Destruction of cartilage in arthritis is partially attributable to metalloproteinases released by the chondrocytes in response to interleukin-1 (IL-1). Bovine articular chondrocytes treated with interleukin-1 alpha (IL-1 alpha) produced enhanced levels of stromelysin mRNA, however, Northern blots could not determine the percentage of cells responding. Exposure of bovine articular chondrocytes to IFN-gamma induced the expression of bovine HLA-DR (boHLA-DR) antigen in 50% of the cells. Using a modified cell sorting technique, chondrocytes that expressed class II MHC antigens produced two fold greater stromelysin mRNA than chondrocytes that did not express this antigen. In contrast, collagen type II mRNA levels were similar in chondrocytes, regardless of the expression of class II MHC antigens. In situ hybridization studies showed that less than half of all cartilage chondrocytes were induced to synthesize stromelysin mRNA. These observations suggest that IFN-gamma stimulates specific subpopulations of chondrocytes to be functionally active in inflammation-induced metalloprotease secretion.
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PMID:Differential induction of stromelysin mRNA by bovine articular chondrocytes treated with interferon-gamma and interleukin-1 alpha. 841 98

The proteolytic enzyme stromelysin-1 is a member of the family of matrix metalloproteinases and is believed to play a role in pathological conditions such as arthritis and tumor invasion. Stromelysin-1 is synthesized as a pro-enzyme that is activated by removal of an N-terminal prodomain. The active enzyme contains a catalytic domain and a C-terminal hemopexin domain believed to participate in macromolecular substrate recognition. We have determined the three-dimensional structures of both a C-truncated form of the proenzyme and an inhibited complex of the catalytic domain by X-ray diffraction analysis. The catalytic core is very similar in the two forms and is similar to the homologous domain in fibroblast and neutrophil collagenases, as well as to the stromelysin structure determined by NMR. The prodomain is a separate folding unit containing three alpha-helices and an extended peptide that lies in the active site of the enzyme. Surprisingly, the amino-to-carboxyl direction of this peptide chain is opposite to that adopted by the inhibitor and by previously reported inhibitors of collagenase. Comparison of the active site of stromelysin with that of thermolysin reveals that most of the residues proposed to play significant roles in the enzymatic mechanism of thermolysin have equivalents in stromelysin, but that three residues implicated in the catalytic mechanism of thermolysin are not represented in stromelysin.
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PMID:Stromelysin-1: three-dimensional structure of the inhibited catalytic domain and of the C-truncated proenzyme. 853 33

Catalytic RNA molecules, or ribozymes, have generated significant interest as potential therapeutic agents for controlling gene expression. Although ribozymes have been shown to work in vitro and in cellular assays, there are no reports that demonstrate the efficacy of synthetic, stabilized ribozymes delivered in vivo. We are currently utilizing the rabbit model of interleukin 1-induced arthritis to assess the localization, stability, and efficacy of exogenous antistromelysin hammerhead ribozymes. The matrix metalloproteinase stromelysin is believed to be a key mediator in arthritic diseases. It seems likely therefore that inhibiting stromelysin would be a valid therapeutic approach for arthritis. We found that following intraarticular administration ribozymes were taken up by cells in the synovial lining, were stable in the synovium, and reduced synovial interleukin 1 alpha-induced stromelysin mRNA. This effect was demonstrated with ribozymes containing various chemical modifications that impart nuclease resistance and that recognize several distinct sites on the message. Catalytically inactive ribozymes were ineffective, thus suggesting a cleavage-mediated mechanism of action. These results suggest that ribozymes may be useful in the treatment of arthritic diseases characterized by dysregulation of metalloproteinase expression.
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PMID:Nuclease-resistant ribozymes decrease stromelysin mRNA levels in rabbit synovium following exogenous delivery to the knee joint. 857 Jun 29

Stromelysin, a representative matrix metalloproteinase and target of drug development efforts, plays a prominent role in the pathological proteolysis associated with arthritis and secondarily in that of cancer metastasis and invasion. To provide a structural template to aid the development of therapeutic inhibitors, we have determined a medium-resolution structure of a 20-kDa complex of human stromelysin's catalytic domain with a hydrophobic peptidic inhibitor using multinuclear, multidimensional NMR spectroscopy. This domain of this zinc hydrolase contains a mixed beta-sheet comprising one antiparallel strand and four parallel strands, three helices, and a methionine-containing turn near the catalytic center. The ensemble of 20 structures was calculated using, on average, 8 interresidue NOE restraints per residue for the 166-residue protein fragment complexed with a 4-residue substrate analogue. The mean RMS deviation (RMSD) to the average structure for backbone heavy atoms is 0.91 A and for all heavy atoms is 1.42 A. The structure has good stereochemical properties, including its backbone torsion angles. The beta-sheet and alpha-helices of the catalytic domains of human stromelysin (NMR model) and human fibroblast collagenase (X-ray crystallographic model of Lovejoy B et al., 1994b, Biochemistry 33:8207-8217) superimpose well, having a pairwise RMSD for backbone heavy atoms of 2.28 A when three loop segments are disregarded. The hydroxamate-substituted inhibitor binds across the hydrophobic active site of stromelysin in an extended conformation. The first hydrophobic side chain is deeply buried in the principal S'1 subsite, the second hydrophobic side chain is located on the opposite side of the inhibitor backbone in the hydrophobic S'2 surface subsite, and a third hydrophobic side chain (P'3) lies at the surface.
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PMID:Solution structure of the catalytic domain of human stromelysin complexed with a hydrophobic inhibitor. 858 Aug 39

The effect of expression of c-fos gene on proteoglycan synthesis, one of the important markers of cartilage metabolism, was examined by introducing the c-fos DNA into HCS 2/8 chondrocytes. The [35S]sulfate incorporation into proteoglycan was decreased in the c-fos transfectants expressing exogenous c-fos mRNA, when compared to a control transfectant. A significant increase in transcription of MMP-3 with the suppressed transcription of aggrecan and TIMP-1 were also observed in the c-fos transfectants. Moreover, analysis of the effect of AP-1 proteins on the collagenase and TIMP-1 promoters in gastric carcinoma KKLS cells revealed that c-Fos combined with any of the Jun-related proteins failed to stimulate the TIMP-1 promoter, though collagenase promoter was effectively activated by any Fos/Jun-related protein heterocomplex. These findings indicate that the c-fos expression may govern the cartilage metabolism and hence may play an important role in the pathogenesis of joint destruction in arthritis.
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PMID:Expression of c-fos gene inhibits proteoglycan synthesis in transfected chondrocyte. 860 60

A chimeric Adenovirus-Simian Virus 40 (AdSV40) containing the large T antigen was used to transform rheumatoid synovial fibroblasts. A rheumatoid synovial fibroblast cell line was established by infection of primary rheumatoid arthritis (RA) synovial fibroblasts at Passage 10 with AdSV40 recombinants followed by selection in semisoft agarose cultures. The transformed cells grew anchor independent, exhibited continuous proliferation (> 65 passages) in monolayer culture, and formed multiple visible foci. The transformed synovial fibroblasts showed expression of the simian virus 40 large T antigen in the nucleus as determined by immunofluorescence staining. In addition, indirect immunofluorescence staining demonstrated that the transformed cells stained specifically with a fibroblast-specific antibody 1B10. Studies involving expression of metalloproteinases showed that collagenase and stromelysin were induced by phorbal 12-myristate 13-acetate (PMA), and such an induction was repressed by dexamethasone typical of primary RA fibroblasts. Levels of mRNAs for IL-1 beta, TNF-alpha, and c-jun were increased by PMA, and the mRNA transcripts of these genes were also repressed by addition of dexamethasone to the culture media. Our results indicate that transformed RA synovial fibroblasts display a similar gene expression pattern in response to PMA and dexamethasone as observed for untransformed primary RA synovial fibroblasts. These transformed rheumatoid arthritis synovial fibroblast cells provide an ideal cell culture model in which to test the efficacy of novel arthritis gene therapy reagents.
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PMID:Characterization of a SV40-transformed rheumatoid synovial fibroblast cell line which retains genotypic expression patterns: a model for evaluation of anti-arthritic agents. 902 33

We developed a method to isolate well defined joint specimens from different compartments of normal and arthritic murine knee joints in which mRNA levels of stromelysin and IL-1 were semiquantified using RT-PCR. Joint capsule specimens were isolated on medial and lateral sides of the patella with a biopsy punch. Cartilage layers were isolated from patellae after a mild decalcification with EDTA. EDTA treatment had no effect on the amount and efficiency of amplification of mRNA when tested on isolated chondrocytes. After induction of experimental arthritis, stromelysin mRNA was elevated approximately 50 times in both joint capsule and cartilage. IL-1 was elevated 100 times in joint capsule but only 10 times in cartilage. Kinetic analysis of mRNA levels in cartilage during arthritis showed a prolonged elevation of stromelysin mRNA compared to IL-1. The variation in mRNA levels between joints of individual mice proved to be low, showing that sampling of the specimens and subsequent RT-PCR can be performed reliably. The current method offers a valuable approach to study gene expression in knee joints during murine experimental arthritis.
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PMID:Quantification of mRNA levels in joint capsule and articular cartilage of the murine knee joint by RT-PCR: kinetics of stromelysin and IL-1 mRNA levels during arthritis. 903 19

Carboxyalkyl peptides containing a biphenylylethyl group at the P1' position were found to be potent inhibitors of stromelysin-1 (MMP-3) and gelatinase A (MMP-2), in the range of 10-50 nM, but poor inhibitors of collagenase (MMP-1). Combination of a biphenylylethyl moiety at P1', a tert-butyl group at P2', and a methyl group at P3' produced orally bioavailable inhibitors as measured by an in vivo model of MMP-3 degradation of radiolabeled transferrin in the mouse pleural cavity. The X-ray structure of a complex of a P1-biphenyl inhibitor and the catalytic domain of MMP-3 is described. Inhibitors that contained halogenated biphenylylethyl residues at P1' proved to be superior in terms of enzyme potency and oral activity with 2(R)-[2-(4'-fluoro-4-biphenylyl)ethyl]-4(S)-n-butyl-1,5-pentane dioic acid 1-(alpha(S)-tert-butylglycine methylamide) amide (L-758,354, 26) having a Ki of 10 nM against MMP-3 and an ED50 of 11 mg/kg po in the mouse pleural cavity assay. This compound was evaluated in acute (MMP-3 and IL-1 beta injection in the rabbit) and chronic (rat adjuvant-induced arthritis and mouse collagen-induced arthritis) models of cartilage destruction but showed activity only in the MMP-3 injection model (ED50 = 6 mg/kg iv).
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PMID:Inhibition of stromelysin-1 (MMP-3) by P1'-biphenylylethyl carboxyalkyl dipeptides. 908 93

Matrix metalloproteinases (MMPs) are zinc endopeptidases that are required for the degradation of extracellular matrix components during normal embryo development, morphogenesis and tissue remodelling. Their proteolytic activities are precisely regulated by endogenous tissue inhibitors of metalloproteinases (TIMPs). Disruption of this balance results in diseases such as arthritis, atherosclerosis, tumour growth and metastasis. Here we report the crystal structure of an MMP-TIMP complex formed between the catalytic domain of human stromelysin-1 (MMP-3) and human TIMP-1. TIMP-1, a 184-residue protein, has the shape of an elongated, contiguous wedge. With its long edge, consisting of five different chain regions, it occupies the entire length of the active-site cleft of MMP-3. The central disulphide-linked segments Cys 1-Thr 2-Cys 3-Val 4 and Ser 68-Val 69 bind to either side of the catalytic zinc. Cys 1 bidentally coordinates this zinc, and the Thr-2 side chain extends into the large specificity pocket of MMP-3. This unusual architecture of the interface between MMP-3 and TIMP-1 suggests new possibilities for designing TIMP variants and synthetic MMP inhibitors with potential therapeutic applications.
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PMID:Mechanism of inhibition of the human matrix metalloproteinase stromelysin-1 by TIMP-1. 928 70


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