Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The preovulatory surge of gonadotropins activates a cascade of proteolytic enzymes resulting in the rupture of the follicular wall and the release of a fertilizable ovum during ovulation. In the rat the process is initiated by a rise in follicular tissue-type plasminogen activator, produced predominantly in granulosa cells. Recent studies revealed a preovulatory increase in ovarian collagenolytic activity in vivo and an increase in activatable collagenase in vitro. In view of the complicated control of mammalian collagenase synthesis and activity by local inhibitors and activators, we examined the expression of ovarian interstitial and type IV collagenases and tissue inhibitor of metalloproteinase (TIMP) mRNA after an ovulatory stimulus. Ovarian mRNA was isolated from immature PMSG-treated rats 3, 6, and 9 h after hCG stimulation. Northern blot analyses revealed a mRNA of 1.7 kilobases (kb) hybridizing with the human interstitial collagenase cDNA probe. The levels of this mRNA showed a 25-fold increase between 3-6 h after hCG stimulation. The human cDNA probe of collagenase IV hybridized with a mRNA of 3.1 kb, which showed only a 4-fold increase 9 h after hCG treatment. The interstitial collagenase mRNA was expressed in both granulosa cells of preovulatory follicles and the residual ovarian tissue, whereas the expression of collagenase IV mRNA was limited to the residual tissue. Inhibitors of eicosanoid synthesis, previously shown to block ovulation and the LH/hCG-induced rise in ovarian collagenolysis, suppressed the gonadotropic stimulation of interstitial collagenase mRNA, but slightly stimulated that of collagenase IV. The mouse cDNA probe of TIMP hybridized with a 0.9-kb mRNA, which was stimulated by hCG to reach a maximum (7- to 8-fold increase) between 6-9 h after stimulation. TIMP was expressed and stimulated in both the granulosa cells and the residual tissue. Inhibitors of eicosanoid synthesis did not affect the gonadotropic stimulation of TIMP mRNA. These data support the suggested role of interstitial collagenase in follicle rupture and the essential role of eicosanoids in the mediation of gonadotropic stimulation of interstitial collagenase production and action. The observed stimulation of TIMP mRNA expression by the gonadotropin and the lack of any effect of eicosanoid synthesis inhibitors on this action of LH/hCG offer an additional mechanism by which these inhibitors may block ovulation. Thus, the suppression of ovulation by inhibitors of eicosanoid synthesis may result from selective inhibition of interstitial collagenase expression and undisturbed gonadotropin-stimulated TIMP expression.
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PMID:Preovulatory changes in ovarian expression of collagenases and tissue metalloproteinase inhibitor messenger ribonucleic acid: role of eicosanoids. 165 86

Cleavage of the 45-kDa gelatin-binding fragment of human plasma fibronectin with fibronectinase resulted in the activation of two forms of metalloproteinase with different substrate specificities. The 40-kDa FN-type-IV collagenase A degrades heat-denatured type-I collagen, laminin and also native collagen type IV. The 27-kDa FN-type-IV collagenase B degrades native collagen type IV, but it does not cleave laminin and only poorly degrades gelatin. Both enzymes begin with the same N-terminal sequence VYQPQPH- (residues 262-268 of fibronectin) but, contrary to the FN-type-IV collagenase A, the FN-type-IV collagenase B has lost the C-terminal region of type I repeats, where the major gelatin-binding determinants of fibronectin are located. The FN-type-IV collagenases A and B are sequentially similar to the middle domain (domain II) of collagenase type IV, secreted by H-ras-transformed human bronchial epithelial cells. Substrate and inhibition specificity of FN-type-IV collagenase A and B are different from those of FN-gelatinase and FN-laminase, isolated previously from the central and C-terminal fibronectin domains, respectively. The substrate specificity of both enzymes, characterized in this study, is also different from that of already known matrix-degrading metalloproteinases.
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PMID:Collagen-binding domain of human plasma fibronectin contains a latent type-IV collagenase. 165 29

To investigate the mechanism of cyclosporine (CS)-induced fibrotic gingival enlargement, the effect of CS on the collagenolytic activities of 14 different human gingival fibroblast strains derived from healthy individuals with non-inflammed gingiva was examined in vitro. There was marked heterogeneity among individuals in basal levels of collagenase activity, and there was also variation among the subpopulations derived from one strain. Fibroblasts from different individuals also varied markedly in their collagenolytic response to CS (0.1 to 0.75 micrograms/ml). In most strains, CS decreased collagenase activity, but in some, the drug caused no change or significantly increased activities. In most of the subpopulations CS significantly decreased collagenolytic activity. Two of the fibroblasts strains and the subpopulations described above were examined for the production of immunoreactive collagenase and tissue inhibitor of metalloproteinase (TIMP). The two strains made similar amounts of collagenase, but differed markedly in TIMP levels; CS affected their collagenase production differently but had similar effects on TIMP. Among the subpopulations there was variation in the production of collagenase, although none made detectable levels of TIMP; they also varied in the production of both proteins in response to CS. In two of the subpopulations and in both strains at some concentrations, the effect of CS on the relative levels of collagenase and TIMP could account for the decreased collagenase activity; i.e., the level of collagenase was unchanged or decreased, and TIMP production was unchanged or increased. This study demonstrates the variation among individuals as well as intrastrain heterogeneity of human gingival fibroblasts with regard to collagenase activity and the production of collagenase and TIMP. The heterogeneity of the collagenolytic response of different gingival fibroblast strains and their subpopulations to CS treatment may partly explain the susceptibility of only some individuals to CS-induced gingival enlargement.
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PMID:Fibroblast heterogeneity in collagenolytic response to cyclosporine. 165 19

The expression of messenger RNA encoding neutral metalloproteinases and the tissue inhibitor of metalloproteinases (TIMP) in human arthritic synovium was evaluated in situ, using RNA probes. Interstitial collagenase and stromelysin were expressed by synovial lining cells in patients with active rheumatoid arthritis (RA). Proteinase messenger RNA was found both in cells expressing mononuclear phagocyte antigens and in cells that were negative for the antigens. TIMP was also expressed predominantly along the synovial lining layer. In highly inflammatory RA, TIMP expression appeared less intense than that of the proteases. In osteoarthritic synovium, TIMP was expressed at easily detectable levels, whereas the expression of collagenase and stromelysin was less prominent. The balance between expression of the metalloproteinases and of the metalloproteinase inhibitor in synovium appears to be altered during inflammation. These results are consistent with the notion that synovium plays different roles in the cartilage damage of RA and of osteoarthritis.
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PMID:Expression of metalloproteinases and metalloproteinase inhibitor in human arthritic synovium. 165 8

Synovial fibroblasts freshly isolated from the rheumatoid joint are characterized by their marked connective tissue degradative ability. This phenotype includes the ability to secrete large amounts of the matrix-degrading metalloproteinases, collagenase, and stromelysin. We have found that another aspect of this phenotype is the constitutive expression at both protein and mRNA levels of a 92-kD gelatinolytic metalloproteinase, which is not secreted by normal dermal or lung fibroblasts and is immunologically cross-reactive with a type V collagenase expressed by activated macrophages and neutrophils. Expression of this 92-kD metalloproteinase confers upon the fibroblasts the capacity to degrade collagenase- and stromelysin-resistant interstitial elements, such as collagen types IV, V and XI. In contrast to the 92-kD metalloproteinase, a 68-kD gelatinase (type IV collagenase) was expressed by all fibroblast types studied, indicating that its regulation is distinct from that of the 92-kD gelatinase. To identify what cytokines may be important in the induction of the rheumatoid synovial phenotype, including expression of the 92-kD gelatinase, we exposed normal dermal fibroblasts to a number of cytokines including many known or considered likely to be present in rheumatoid synovial fluid and tissue. Although IL-1 beta, tumor necrosis factor-alpha, lymphotoxin, platelet-derived growth factor, and basic fibroblast growth factor were capable of stimulating fibroblasts to secrete collagenase, only tumor necrosis factor-alpha, lymphotoxin, and IL-1 beta were able to induce expression of the 92-kD gelatinase, demonstrating discordant regulation of the two metalloproteinases. Expression of the 68-kD gelatinase was independent of that of the 92-kD gelatinase, as demonstrated at the protein and mRNA levels. Late passage rheumatoid synovial fibroblasts, which no longer constitutively expressed the 92-kD gelatinase, displayed an accentuated response to IL-1 beta when compared to normal dermal fibroblasts. Thus, in addition to IL-1 beta, tumor necrosis factor-alpha or lymphotoxin may contribute to the expression of a specific rheumatoid synovial phenotype in vivo that is associated with progressive matrix destruction.
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PMID:Constitutive expression of a 92-kD gelatinase (type V collagenase) by rheumatoid synovial fibroblasts and its induction in normal human fibroblasts by inflammatory cytokines. 165 48

The action of purified rabbit bone stromelysin was investigated on proteoglycan aggregates from pig laryngeal cartilage. The enzyme caused a rapid fall in viscosity of proteoglycan aggregate solution (6 mg/ml), and the products of a partial digest (60% loss of relative viscosity) and a complete digest (95% loss of relative viscosity) were characterized. Analysis by gel chromatography on Sepharose 2B under associative conditions showed that 95% of the glycosaminoglycans in the complete digest were in small-sized fragments, whereas most of the hyaluronan-binding G1 domain and link protein remained intact and bound to hyaluronan. In contrast, there was extensive digestion of the G2 domain which resulted in 76% loss in its detection by immunoassay. Analysis of the partial digest also showed considerable loss (40%) of detection of the G2 domain, but the glycosaminoglycan-rich fragments were much larger than in the complete digest. There was also much less cleavage to create small fragments containing the G1 domain. This was evident on SDS/PAGE analysis where a 58 kDa G1 domain fragment was abundant in the complete digest, but was only present in small amounts in the partial digest. There was also only very limited conversion of link protein from a 44 kDa form to a 40 kDa form. The digestion of proteoglycan aggregate (6 mg/ml) by stromelysin was unaffected by the addition of a high concentration of extra chondroitin sulphate chains (14 mg/ml), and the digestion of proteoglycan monomer showed that the G1 domain was resistant to stromelysin digestion even when not bound to hyaluronan and link protein. The results show that stromelysin degrades the proteoglycan protein core with major cleavages close to, but not within, the G1 domain, and extensive cleavage in other regions. Experiments with purified collagenase, a metalloproteinase structurally related to stromelysin, showed that it too cleaved proteoglycan at several sites within the glycosaminoglycan-rich region of the core protein. Metalloproteinase attack on proteoglycan thus not only occurs with stromelysin but also with collagenase.
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PMID:Metalloproteinase digestion of cartilage proteoglycan. Pattern of cleavage by stromelysin and susceptibility to collagenase. 165 87

The expression of collagenolytic activity by cells represents the rate-limiting step in the turnover of collagen during remodeling. The collagenase gene is transcriptionally activated in normal dermal or rheumatoid synovial fibroblasts by interleukin-1 beta (IL-1 beta), resulting in secretion of trypsin-activatable procollagenase measuring in the range of 2.0-5.0 units/10(6) cells/48 h in the 14C-fibril assay. The addition of interferon-gamma (IFN-gamma; 50-100 units/ml) inhibits the expression of collagenase activity by 45-80% in these cells. The IL-1 beta induction of procollagenase protein was not altered by IFN-gamma, as judged by Western blot analysis using a monoclonal antibody to collagenase and by gelatin zymography, and procollagenase mRNA was also unaltered, as assessed by Northern blot analysis. Because collagenolytic activity is also controlled by the quantity of tissue inhibitor of metalloproteinases present, its expression was examined by Western blot analysis using a polyclonal antibody to tissue inhibitor of metalloproteinases and by reverse gelatin zymography. Tissue inhibitor of metalloproteinase protein was found to be unaltered or slightly less abundant in conditioned media from cultures treated with IL-1 beta and IFN-gamma when compared with that from cultures treated with IL-1 beta alone. However, the expression of the metalloproteinase activator of procollagenase, stromelysin, was found to be significantly inhibited by the addition of IFN-gamma. Addition of purified activated stromelysin to these conditioned media completely reconstituted collagenolytic activity. These observations demonstrate in an intact system that stromelysin is a specific activator necessary for the development of collagenolytic activity. Despite stromelysin's lack of catalytic activity against collagen, its expression can serve as a control point in the regulation of collagenolysis.
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PMID:Stromelysin expression regulates collagenase activation in human fibroblasts. Dissociable control of two metalloproteinases by interferon-gamma. 166 Apr 74

Extensive remodeling of the follicular extracellular matrix occurs during the process of ovulation. This remodeling involves the breakdown of collagen, which is regulated, in part, by the action of the metalloproteinase collagenase and its associated inhibitors. In the present study, follicular metalloproteinase inhibitors were characterized to determine whether they were serum-borne or of ovarian origin, possibly a tissue-derived inhibitor known as tissue inhibitor of metalloproteinase (TIMP). Human follicular fluid and granulosa cells were obtained from preovulatory follicles of patients in an in vitro fertilization program. Chromatographic separation of follicular fluid on Sepharose 6B resulted in two peaks of inhibitory activity. The large molecular radius (Mr) inhibitor was similar in size to the serum-borne metalloproteinase inhibitor alpha 2-macroglobulin (i.e. Mr 700,000) whereas the small Mr inhibitor approximated the size of TIMP (i.e. Mr 29,000). Incubation of aliquots from either of the two peaks of inhibitor activity or an alpha 2-macroglobulin standard with an antibody to alpha 2-macroglobulin decreased the inhibitory activity in both the large Mr peak and the alpha 2-macroglobulin standard by 86.6 +/- 1.7% and 71.5 +/- 7.7% (n = 4, P less than 0.005), respectively, implying cross-reactivity with the alpha 2-macroglobulin antibody. The inhibitory activity in the small Mr peak, however, was unchanged. Northern analysis of total granulosa cell RNA demonstrated TIMP messenger RNA (mRNA) in all eight granulosa cell samples examined whereas alpha 2-macroglobulin mRNA was virtually undetectable. A positive correlation (r = 0.85, P less than 0.01) was observed between the levels of TIMP mRNA and the ratio of the follicular estradiol-progesterone concentration. However, inhibitor activity in the follicular fluid was not correlated with the levels of TIMP mRNA (r = 0.05). These findings confirm the presence of alpha 2-macroglobulin in follicular fluid and demonstrate that human preovulatory granulosa cells contain mRNA for TIMP, an inhibitor that regulates metalloproteinases such as collagenase, gelatinase, and proteoglycanase. Additionally, the expression of TIMP mRNA is steroid related and may be hormonally regulated. It is proposed that TIMP produced in the granulosa cell compartment in conjunction with alpha 2-macroglobulin from the serum may act to control the site and extent of ovarian connective tissue remodeling.
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PMID:Alpha 2-macroglobulin and tissue inhibitor of metalloproteinases: collagenase inhibitors in human preovulatory ovaries. 169

Primary and passaged human synovial fibroblasts isolated from rheumatoid pannus were treated with recombinant interleukin-1 (IL-1) alpha or beta, tumor necrosis factor-alpha (TNF), or phorbol myristate acetate (PMA) to determine the effects of these stimuli on the relative expression of stromelysin, collagenase, and tissue inhibitor of metalloproteinases (TIMP). The steady-state mRNA levels for these genes and glyceraldehyde-3-phosphate dehydrogenase were determined on Northern blots. Immunoblot analyses of the conditioned media using monoclonal antibodies generated against recombinant human stromelysin, collagenase, or TIMP showed that protein levels reflected the corresponding steady-state mRNA levels. The results revealed that 1) stromelysin and collagenase were not always coordinately expressed; 2) IL-1 was more potent than TNF or PMA in the induction of stromelysin expression; 3) neither IL-1 nor TNF significantly affected TIMP expression; 4) PMA induced both metalloproteinase and TIMP expression; and 5) the combination of IL-1 plus TNF had a synergistic effect on stromelysin expression. Dose response and time course experiments demonstrated that the synergistic effect of IL-1 plus TNF occurred at saturating concentrations of each cytokine and lasted for 7 days. In summary, the ability of IL-1 and TNF to preferentially induce stromelysin and collagenase expression, versus TIMP, may define a pivotal role for these cytokines in the pathogenesis of rheumatoid arthritis.
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PMID:Discoordinate expression of stromelysin, collagenase, and tissue inhibitor of metalloproteinases-1 in rheumatoid human synovial fibroblasts. Synergistic effects of interleukin-1 and tumor necrosis factor-alpha on stromelysin expression. 169 73

Immature female Sprague-Dawley rats were primed with 20 IU eCG at 28 days of age and treated with 10 IU hCG 48 h later. Ovulation followed at 12-14 h. Ovaries were extracted at various times after hCG by use of Triton X-100 and 10 mM CaCl2 (Triton extract) followed by heating to 60 degrees C for 6 min with 0.1 M CaCl2 in 50 mM Tris/0.15 M NaCl, pH 7.5 (heat extract). These extracts were tested for their ability to inhibit tissue metalloproteinases by use of the small uterine metalloproteinase (UMP) of the rat. The ovary contains three plasma-derived inhibitors (alpha 1-macroglobulin [alpha 1 M], alpha 2-macroglobulin [alpha 2 M], and alpha 1 inhibitor3 [alpha 1I3]) and one tissue-derived inhibitor of the tissue inhibitor of metalloproteinases (TIMP) family. alpha 1 I3 was shown to inhibit UMP and rat collagenase. The concentration of the tissue inhibitor rose 5-fold from 0.6 micrograms UMP blocked per gram wet tissue in ovaries not primed with eCG to 3.2 micrograms UMP blocked at 8 h after hCG. Over this same time interval, the sum of alpha 1M + alpha 2M per gram of ovary rose 7-fold from 3.2 to 22.4 micrograms UMP inhibited and alpha 1I3 rose 2-fold from 4.4 to 10.7 micrograms UMP inhibited. The increases in the tissue inhibitor are interpreted to be due to increased synthesis by the tissue, whereas the changes in alpha-macroglobulins are postulated to be due to increased vascularity and increased permeability of the vessels.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:A tissue inhibitor of metalloproteinases and alpha-macroglobulins in the ovulating rat ovary: possible regulators of collagen matrix breakdown. 172 97


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