Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We examined production and tissue localization of matrix metalloproteinase (MMP)-1 (tissue collagenase), MMP-2 (gelatinase A), MMP-3 (stromelysin-1), MMP-9 (gelatinase B), tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 in human breast carcinomas. In more than half of the cases, MMP-1, MMP-2, MMP-9, TIMP-1 and TIMP-2 were immunolocalized in carcinoma cells and MMP-2 was on the carcinoma cell membranes as well, whereas MMP-3 was positively stained in less than 15% of the cases. MMP-1 staining in carcinoma cells was significantly higher in scirrhous carcinoma than in other types of carcinoma. MMP-9 expression was remarkably higher in the carcinoma cases with lymphnode metastasis than in the non-metastatic cases. MMP-3 was mainly expressed in T-lymphocytes infiltrated in the tumor stroma. Stromal fibroblasts were positive for all these MMPs except for MMP-3. The TIMP-1 levels released into the culture media by carcinoma tissues were significantly lower than those by fibroadenoma tissues, although there were no significant differences in the levels of MMP-1, MMP-2, MMP-9 and TIMP-2. Gelatin zymographical analyses showed that the activation rate of the zymogen of MMP-2 (proMMP-2) is significantly higher in the more advanced carcinoma group with lymphnode metastasis than in the metastasis-negative and fibroadenoma groups. These data indicate that MMP-1, MMP-2 and MMP-9 are highly expressed in human breast carcinoma tissue and suggest that activation of proMMP-2 may be an indicator of lymphnode metastasis of the breast carcinoma.
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PMID:Production of matrix metalloproteinases and tissue inhibitors of metalloproteinases in human breast carcinomas. 876 24

The role of matrix metalloproteinases in parathyroid hormone (PTH)-induced bone resorption was assayed using a fetal rat limb bone culture system. Cotreatment of bones with PTH and recombinant inhibitor of metalloproteinases, TIMP-1, in vitro, inhibited the PTH-stimulated 45Ca release from the limb bones without affecting beta-glucuronidase release. TIMP-1 was fully effective when added during only the final 24 h of a 72 h culture with PTH but was ineffective when added for only the first 24 h of the 72 h culture. In contrast, calcitonin (CT) was effective when added for either the first 24 or the final 24 h of the culture. Using in situ hybridization, the mRNA for collagenase was detected in mononuclear cells of cultured bone. Treatment of the bones with PTH resulted in an increase in the number of cells producing collagenase mRNA, some of which had osteoclastic morphology, PTH also caused a dramatic induction of the mRNA for the 92-kD gelatinase B metalloproteinase in both mononuclear and osteoclastic cells. There was no detectable mRNA for the metalloproteinases stromelysin-1, stromelysin-2, or matrilysin in PTH-treated or control cultures. These results suggest that PTH-induced bone resorption is mediated, at least in part, by the induction of collagenase and gelatinase B mRNA in bone cells.
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PMID:Parathyroid hormone-induced resorption in fetal rat limb bones is associated with production of the metalloproteinases collagenase and gelatinase B. 877 Jun 99

Extracellular matrix is the principal component of the fibrous caps of atherosclerotic plaques and intimal hyperplastic lesions of reconstructed arteries. Interstitial collagen form an important part of the matrix, and the balance between collagen synthesis and degradation by interstitial collagenase (matrix metalloproteinase-1, MMP-1) may determine whether plaques rupture or vessels develop stenosis. We examined type I procollagen gene expression in human atherosclerotic and restenotic carotid arteries using in situ messenger RNA (mRNA) hybridization and the expression of MMP-1 and its endogenous inhibitor (tissue inhibitor of metalloproteinases-1, TIMP-1) by immunohistochemistry. Compared with normal arteries, atherosclerotic plaques bed increased expression of immunoreactive MMP-1 and TIMP-1 with modest increase of type 1 procollagen mRNA. Early restenotic lesions (< 1.5 years) contained abundant type I procollagen mRNA but little immunoreactive MMP-1 and TIMP-1. Late restenotic lesions (> 4 years) resembled atheroma and exhibited increased immunoreactive MMP-1 and TIMP-1 as well as abundant type I procollagen mRNA. Compared with atherosclerotic plaques, type I procollagen is increased and MMP-1 is decreased in early restenotic lesions. MMP-1 and TIMP-1 expressions are upregulated in lesions with a clear atheroma. These findings suggest that the balance between proteolysis and matrix synthesis may influence both the stability of atheromatous plaques and the development of restenotic lesions.
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PMID:Expression of collagen, interstitial collagenase, and tissue inhibitor of metalloproteinases-1 in restenosis after carotid endarterectomy. 877 33

The present study was carried out to characterize the patterns of expression of matrix metalloproteinases or their tissue inhibitor (TIMP-1) in normally healing, acute vs. chronic, skin wounds. In situ hybridization was performed to localize collagenase, stromelysin-1, stromelysin-2, matrilysin, urokinase plasminogen activator (uPA) and TIMP-1 mRNAs in 14 chronic venous ulcers and 10 normally healing wounds, representing different time points after wounding. Surgical wounds, made in piglets harvested at several time points, were studied as controls. Collagenase, stromelysin-1 and -2, as well as uPa, were expressed in keratinocytes in both acute and chronic wounds, while epithelial TIMP-1 mRNA was not detected in any chronic wound biopsies studied. However, TIMP-1 was expressed at the epithelial edges of both acute human and pig wounds. Our results suggest that the balance between metalloenzymes and their inhibitor TIMP-1, is disturbed, in poorly healing wounds.
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PMID:Patterns of matrix metalloproteinase and TIMP-1 expression in chronic and normally healing human cutaneous wounds. 877 59

The proteolytic erosion of the temporal bone is the key event in the pathognomonic course of cholesteatoma progression. The molecular mechanisms of bone resorption, endangering the ossicles, the inner ear, the facial nerve, large vessels or the brain, are not understood. Recently, a new family of proteolytic enzymes, the matrix-metalloproteinases (MMP's) has been described and identified, which seems to play a pivotal role in matrix- and bone homeostasis and inflammatory osteolytic diseases, e.g. osteoarthritis and periodontitis. These enzymes are sophisticatedly controlled by specific inhibitors and activation cascades. We investigated whether human cholesteatoma tissue expresses MMP's and MMP-inhibitors. By immunocytochemistry of cholesteatoma-cryosections, the expression of MMP-2 (72 kD collagenase), MMP-9 (92 kD collagenase), and MMP-3 (stromelysin-1) could be seen to be strictly confined to the basal and suprabasal cell layer of the cholesteatoma epithelium. The neutrophil collagenase (MMP-8) showed a more disseminated expression in the epithelium and the granulation tissue as well. The tissue inhibitor of metalloproteases, TIMP-1, could be detected only in very limited areas of the granulation tissue in a quite randomized manner. Therefore, a derailment in favor of proteolysis of the normally tightly controlled MMP-system might be postulated. The results indicate that members of the MMP-family could play an active role in the molecular mechanisms of cholesteatoma invasion into the temporal bone. This offers new insights into the pathophysiology of the disease and of potential therapeutic approaches.
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PMID:Expression of matrix-metalloproteinases and their inhibitors in human cholesteatomas. 879 Jul 47

Tissue inhibitor of metalloproteinase-I (TIMP-1) is a slow, tight-binding inhibitor of fibroblast-type collagenase. Time-course data from inhibition experiments were analyzed by graphic analysis, by nonlinear regression of the analytic integrals of the rate equations and by nonlinear regression with numeric integration of the rate equations. With the same assumptions, approximations and data, all three methods of analysis produced the same model preferences and values for the kinetic parameters. The time-course data for the inhibition of fibroblast-type collagenase by TIMP-1 are best described by the equations for a noncompetitive two-step mechanism, in which an inactive, rapidly formed, reversible complex slowly forms an inactive, tight complex. However, from the analysis of data from experiments at concentrations of TIMP-1 comparable to that of collagenase, it is apparent that free TIMP-1 also functions in the breakdown of the tight complex. The rapidly formed complex has a dissociation constant of 8 nM and reacts to the tight complex with a first-order rate constant of 0.003 s-1. The back reaction of the tight complex to the rapid complex has a second-order rate constant of 5 x 10(4) M-1 s-1. The resulting global dissociation constant of the tight complex is 0.1 nM at 3 nM TIMP-1 and collagenase concentration. Collagenase without the carboxyl-terminal domain (mini-collagenase) is inhibited by TIMP-1 according to a mechanism, in which the rapidly formed complex has such a high dissociation constant (247 nM) that it effectively constitutes a one-step mechanism, in which TIMP-1 binds with an apparent second-order rate constant of 9.6 x 10(4) mol-1 s-1 and the enzyme-TIMP-1 complex dissociates with a first order rate constant of 0.00026 s-1. The apparent global dissociation constant for the tight complex (2.7 nM) is higher than that for the fibroblast-type collagenase. Participation of TIMP-1 in the dissociation is not demonstrable. Therefore, the carboxyl-terminal domain of fibroblast-type collagenase is important for the initial, rapid binding of TIMP-1 and the initial complex contributes to the overall binding.
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PMID:The mechanism of inhibition of collagenase by TIMP-1. 879 26

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases which are secreted from cells as zymogens and can be activated by treatment with organomercurial reagents or limited proteolysis. The proenzyme forms of MMP-2 (gelatinase A) and MMP-9 (gelatinase B) are found in complex with tissue inhibitor of metalloproteinases (designated proMMP-2/ TIMP-2 and proMMP-9/TIMP-1, respectively). The proposed mechanism of activation by mercurial compounds involves the induction of a conformational change in the zymogen which leads to propeptide autoprocessing. To investigate the possibility of conformational differences in MMPs, solute quenching of MMP intrinsic fluorescence was used to probe the relative exposure of tryptophan residues in latent and mercurial-activated MMPs. Our data demonstrate that fluorescence quenching of the proMMP-2/TIMP-2 complex by either acrylamide or iodide is significantly increased following mercurial activation. In contrast, no significant change in tryptophan accessibility accompanies mercurial treatment of either proMMP-2 or TIMP-2 alone, or mercurial-activated MMP-2 mixed with TIMP-2. To determine whether the enhanced fluorescence quenching was unique to the activated proMMP-2/TIMP-2 complex, similar experiments were performed using MMP-1, MMP-3, and MMP-9/TIMP-1 complex. In all cases, both latent and mercurialtreated MMPs exhibited similar fluorescence quenching profiles, suggesting that there are no significant conformational differences between the zymogen and activated forms of MMP-1, -2, -3, or -9/TIMP-1. The enhanced fluorescence quenching observed with mercurial-treated proMMP-2/TIMP-2 is indicative of increased exposure of a previously buried tryptophan residue(s), providing evidence for a structural rearrangement of the activated complex. These data, together with our previous biochemical observation that mercurial treatment of proMMP-2/TIMP-2 exposes the MMP-2 active site without propeptide processing (Y. Itoh et al. (1995) Biochem. J. 308, 645-651), suggest that the activated proMMP-2 in the complex may represent a transitional conformational intermediate in MMP activation.
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PMID:Fluorescence quenching studies of matrix metalloproteinases (MMPs): evidence for structural rearrangement of the proMMP-2/TIMP-2 complex upon mercurial activation. 880 67

Human heart matrix metalloproteinases (MMP) are present in the latent form and activated in the failing heart. To examine whether the MMP activation was due to gene and/or post-translational modification, we analysed tissue from 10 explanted hearts due to coronary heart disease (CHD) and five normal left atrial tissue from donor hearts. Based on in situ immunolabeling MMP-1, tissue inhibitor of metalloproteinase (TIMP-1) and collagen were co-localized in the interstitial tissue. Based on sandwich ELISA, TIMP-1 and MMP-1 levels were 37 +/- 8 ng/mg and 9 +/- 2 ng/mg in normal tissue (P < 0.01) and 12 +/- 5 ng/mg and 75 +/- 11 ng/mg in the infarcted tissue (P < 0.01), respectively. These levels suggest repression of TIMP-1 during myocardial infarction. Northern blot analysis indicated that the mRNAs for both MMP-1 and TIMP-1 were increased three-to four-fold in the infarcted tissue as compared to the normal tissue, suggesting upregulation of MMP and TIMP gene transcription following infarction. Based on in situ tissue overlay zymography, the generalized activation of MMP was observed in the interstitium of the infarcted heart. Zymographic and immunoblot analysis demonstrated the presence of one band at 66 kDa (MMP-2) in the normal tissue and several bands at 92 (MMP-9), 66 (MMP-2) and 54 kDa (MMP-1) in the infarcted heart. Incubation of the zymographic gel with metal chelator (phenanthroline) abolished bands at 92 kDa and 54 kDa but phenanthroline did not abolish the lytic band at 66 kDa. The 66 kDa band was completely abolished in the presence of phenanthroline and phenyl methyl sulfonyl fluoride (PMSF). 2D-zymographic analysis suggested that the lytic band at 66 kDa was a mixture of two neutral proteinases with different isoelectric point. Plasminogen/gelatin zymographic analysis of infarcted tissue extract indicated that the band at 66 kDa was plasmin generated due to increased expression of tissue plasminogen activator (tPA) activity. In relation to increased expression of gelatinase in the infarcted tissue, our data suggest that gelatinase B (92 kDa) is induced in diseased heart. The results suggest that tPA converts plasminogen to plasmin which, in turn, activates MMPs and inactivates TIMP-1 post-translationally following ischemic cardiomyopathy.
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PMID:Post-transcriptional regulation of extracellular matrix metalloproteinase in human heart end-stage failure secondary to ischemic cardiomyopathy. 884 29

The aim of the study was to immunolocalise interstitial collagenase (MMP-1) and the tissue inhibitor of metalloproteinases (TIMP-1) in ulcerating corneas from patients with rheumatoid arthritis, to determine whether changes in expression are associated with destructive corneal disease. Collagenase was expressed by stromal cells in 8 of 8 ulcerating corneas but was not seen in normal tissue (n = 3). TIMP-1 was abundant throughout the normal stroma, but was much reduced or absent from diseased corneas. Collagenase staining was frequently more intense near the epithelial surface and associated with a cellular infiltrate consisting of activated antigen-presenting cells (HLA-DR+), many of which were macrophages (CD68+) and derived from the epithelium or limbus (S100+). Interstitial collagenase produced by infiltrating macrophages and/or stimulated corneal fibrocytes is probably a major mediator of collagen degradation in rheumatoid corneal ulceration. In addition, reduced levels of TIMP-1 expression are consistent with collagenase activity and tissue destruction. Epithelial-stromal cell interactions and the production of local inflammatory mediators are of major importance in the pathogenesis of corneal destruction, although the precise nature of the antigenic stimulation and/or cellular interactions remains to be elucidated.
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PMID:Collagenase (MMP-1) and TIMP-1 in destructive corneal disease associated with rheumatoid arthritis. 884 37

The wavelength dependence for the regulation of two major matrix-metalloproteinases, interstitial collagenase (MMP-1) and stromelysin-1 (MMP-3), and their major inhibitor, tissue inhibitor of metalloproteinases (TIMP-1), was studied in human dermal fibroblasts in vitro. Monochromatic irradiation at 302, 307, 312 and 317 nm with intensities ranging from 20 to 300 J/m2 increased MMP-1 and MMP-3 mRNA steady-state levels and the secretion of the corresponding proteins up to 4.4-fold, whereas almost no increase was observed at wavelengths < 290 nm. In contrast, the synthesis of TIMP-1 increased only marginally. This imbalance may contribute to the severe connective tissue damage related to photoaging of the skin. The wavelengths responsible for MMP-1 and MMP-3 induction reported here are distinct from the absorption spectrum of DNA and are different from results previously reported in the literature. Importantly, they overlap with wavelengths whose intensity is predicted to increase on the earth's surface upon ozone depletion. Intensities and particular wavelengths used in our studies in vitro can be absorbed readily by fibroblasts within the skin in vivo and, thus, are relevant for risk assessment and development of protective agents.
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PMID:Ultraviolet B wavelength dependence for the regulation of two major matrix-metalloproteinases and their inhibitor TIMP-1 in human dermal fibroblasts. 893 89


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