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)

Bone destruction, commonly associated with chronic otitis media, requires collagen degradation. Collagenase, a neutral protease, appears to be an essential component in the process of collagen breakdown. Collagenase was identified within chronically inflamed and normal guinea pig temporal bones using an immunohistochemical technique with fluorescein isothyocyanate and peroxidase-antiperoxidase labels. Localization of the enzyme identifies sites of matrix resorption. Collagenase was found in osteoclasts, osteocytes, mononuclear inflammatory cells, and at resorbing margins. Inflammation increased the intracellular collagenase content of inflammatory bone osteocytes when compared to normal osteocytes using a microspectrofluorometer. It appears that the inflammatory process directly influences bone destruction through the action of mononuclear inflammatory cells and indirectly by stimulating bone cells to increase their proteolytic enzyme production.
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PMID:Localization of collagenase in chronically inflamed guinea pig temporal bone. 22 7

The ultrastructural mechanism of the protease induced blood-brain barrier permeability-increase was studied with horse-radish peroxidase as a tracer. After intravenous injection of collagenase or pronase, a significantly increased number of pinocytotic vesicles was found in brain capillary endothelial cells. alpha-Chymotrypsine did not exert such an action.
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PMID:Mechanism of action of collagenase on the blood-brain barrier permeability. Increase of endothelial cell pinocytotic activity as shown with horse-radish peroxidase as a tracer. 22 73

Polymorphonuclear leukocytes (PMNs) are one of the main sources of enzymes responsible for tissue damage in inflammatory processes. These enzymes are stored in two types of cytoplasmic granules. Azurophil granules contain lysosomal hydrolases, neutral serine proteinases, and bactericidal elements (myeloperoxidase and lysozyme). Specific granules contain collagenase, lysozyme and lactoferrin but lack lysosomal hydrolases. PMNs store all four classes of tissue proteinases, carboxyl, thiol and serine proteinases in the azurophil granules, and metallo proteinases in the specific granules. Three serine proteinases have been identified, elastase, cathepsin G and a third enzyme, which together account for a large proportion of the protein of the azurophil granules. In the course of phagocytic events, all these enzymes are released extracellularly. The neutral proteinases degrade proteoglycans and collagen. In vitro, they stimulate B-lymphocytes, which suggests that they may have immuno-potentiating activity when they are released at sites of chronic inflammation.
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PMID:The polymorphonuclear leukocyte. 34 82

Human erythrocytes, porcine and rat liver cells, porcine spleen lymphocytes and cultured human lymphoma cells (266 Bl) have been labelled with 125I by the lactoperoxidase-H2O2 method. Large amounts of radioactivity were released when the iodinated cells were incubated in different buffers, and the rate of the release varied considerably between the different cells. Incubation at a higher temperature increased the release rate, while metabolic inhibitors such as iodoacetamide, trasylol or sodium azide did not. When collagenase was used during the preparation of spleen lymphocytes, the rate of the radioactivity release was decreased about 50%. Several findings indicated that the released radioactivity originated from free iodide. When the labelled lymphocytes were treated with a nonionic detergent, Nonidet P-40, 90% of the total radioactivity was solubilized. Only 10-15% of the radioactivity was stably bound in macromolecular material. The remaining part, corresponding to the amount of radioactivity released during incubation, was shown to be free iodide. It is concluded that the significance of the 125I-label in living cells has to be studied in each case at the specific experimental conditions used. After the unspecifically trapped iodide is released--normally after about 2 h--the label is considered to be useful for studies with intact cells.
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PMID:The significance of 125I as a tracer for lymphocytes, liver cells and erythrocytes after iodination by the lactoperoxidase-H2O2 technique. 78 77

Release of peroxidase from secretory cells of rat lacrimal gland upon cholinergic stimulation was studied in vitro with single lobules and isolated cells (lacrimocytes). Isolated lobules, kept in Eagle's medium, remain structurally intact and reaction product of peroxidase is confined to cisternae of rough endoplasmic reticulum, elements of the Golgi apparatus, and all secretory granules. Morphologically, exocytosis occurs by membrane fusion and discharge of granule content. The highest rate of peroxidase released from lobules is observed at 10(-4) M carbamylcholine. The specific activity of peroxidase released into the medium is fourfold higher as compared to the lobules. Release of peroxidase is suppressed by atropine when added before or after the addition of carbamylcholine. At 4 degrees C, no peroxidase release occurs upon cholinergic stimulation. The exocytotic release of peroxidase is dependent on energy supply, as indicated by substantial inhibition (at 37 degrees C) under anoxic conditions or in the presence of dinitrophenol, KCN, or carboxyatractyloside. Furthermore, the process is sensitive to colchicine and vinblastine. Isolated lacrimocytes, consiting of 95% secretory acinar cells, are prepared by digestion with collagenase, hyaluronidase, and trypsin. They retain the characteristic polarity of secretory cells in situ, and localization of peroxidase is the same as in lobules. Since isolated lacrimocytes respond to cholinergic stimulation in the same way as lobules, the receptors are not damaged by the isolation procedure and appear to be associated directly with the exocrine cell. Oxygen uptake by isolated lacrimocytes is about 14 nmol O2 X min-1 X 10(-6) cells; it is about doubled by uncoupling with dinitrophenol. Oxygen uptake rises by 20-30% above the resting rate upon cholinergic stimulation. This additional uptake is suppressed by atropine or by added cholinesterase, indicating that continuous receptor occupancy may be required for the energy demand by exocytosis. On the basis of the specific activity of peroxidase in the medium, the energy demand resulting from cholinergic stimulation is estimated to be 0.08 mumol ATP (or energy-rich phosphate bonds) per microgram of protein released from the lacrimocytes.
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PMID:Exocytosis in secretory cells of rat lacrimal gland. Peroxidase release from lobules and isolated cells upon cholinergic stimulation. 95 71

The aim of this study was to describe the normal distribution of calcitonin gene-related peptide (CGRP) and substance P (SP) containing fibres in the knee joint of the mouse and to obtain insight into the changes in innervation associated with degenerative processes in the joint. Arthrosis was induced by a single subpatellar intra-articular injection of bacterial collagenase. After decalcification in EDTA solutions, the CGRP and SP fibres were visualized by peroxidase-antiperoxidase pre-embedding immunocytochemistry for light microscopy. Control experiments on the mouse brain as a reference for the effect of EDTA on the immunostaining showed that the decalcification procedure with EDTA had not impaired the immunostaining. A rich innervation of thin varicose CGRP and SP immunoreactive fibres was found in most peri- and intra-articular tissue components. The periosteum, synovial tissues, the joint capsule and the intra-articular fat tissues were richly innervated. Less intense innervations were also found in the subchondral bone plates of the tibio-femoral joint and of the patella. Fibres were also found in the soft tissues between the patellar tendon and the femoral groove. No differences could be found between the location of CGRP and SP fibres with respect to the localization in the joint, but generally more CGRP fibres were found. The collagenase-induced osteoarthrosis was characterized by sclerosis of the subchondral bone, patellar dislocation, osteophyte formation, synovial proliferation and by severe cartilage abrasion, particularly on the medial side of the femoro-tibial joint. The overall distribution of CGRP and SP fibres was the same as in the control joints. However, major differences were found in all studied joints at specific locations around the cruciate ligaments, in the synovium around the patella, in the soft tissues lateral of the patella and in plica tissue between the patella and femoral groove. The CGRP and SP innervation was no longer detectable by immunolabelling with the antibodies. With a polyclonal antibody to the growth associated protein GAP-43/B-50, signs of degenerated axonal profiles were observed in these locations. At other peripheral locations, such as the muscles, the GAP-43/B-50 distribution was normal. In conclusion, the present study provides detailed information on the localization of CGRP and SP fibres, which may be involved in pain perception. Knowledge of the changes that occur during arthrosis may give more insight into the clinical symptoms.
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PMID:Calcitonin gene-related peptide, substance P and GAP-43/B-50 immunoreactivity in the normal and arthrotic knee joint of the mouse. 128 63

Human neutrophils use the H2O2-myeloperoxidase-chloride system to generate chlorinated oxidants capable of activating metalloproteinase zymogens that hydrolyze not only native and denatured collagens, but also the serine proteinase inhibitor (serpin) alpha 1-proteinase inhibitor (alpha 1 PI). To identify the metalloenzyme that hydrolyzes and inactivates alpha 1 PI, neutrophil releasates were chromatographed over gelatin-Sepharose and divided into fractions containing either progelatinase or procollagenase. The gelatinase-containing fraction cleaved alpha 1 PI in a manner inhibitable by native type V, but not type I, collagen. Conversely, while the collagenase-containing fraction also cleaved alpha 1 PI, this activity was inhibited by type I, but not type V, collagen. Because type I and V collagens are competitive substrates for collagenase and gelatinase, respectively, each of the metalloproteinase zymogens were purified to apparent homogeneity and examined for alpha 1 PI-hydrolytic activities. Both purified gelatinase and collagenase inactivated alpha 1PI by hydrolyzing the serpin within its active-site loop at the Phe352-Leu353 and Pro357-Met358 bonds, albeit with distinct kinetic properties. Furthermore, purified collagenase, but not gelatinase, cleaved a second serpin, alpha 1-antichymotrypsin, by hydrolyzing the Ala362-Leu363 bond within its active-site loop. These data demonstrate that human neutrophils use chlorinated oxidants to activate collagenolytic metalloproteinases whose substrate specificities can be extended to members of the serpin superfamily.
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PMID:Proteolytic inactivation of alpha 1-proteinase inhibitor and alpha 1-antichymotrypsin by oxidatively activated human neutrophil metalloproteinases. 131 27

Mercaptomethylimidazole (MMI) is a potent inducer of gastric acid secretion which is associated with significant inhibition of peroxidase activity of rat gastric mucosa in vivo. A time-dependent increase in acid secretion correlates well with time-dependent decrease in the peroxidase activity. In a chamber experiment in vitro using isolated gastric mucosa, MMI stimulates acid secretion, showing an almost linear response up to 600 microM. The time-dependent increase in acid secretion is also correlated with time-dependent inhibition of the peroxidase activity. This effect is not mediated through oxidation of MMI by flavin-containing mono-oxygenase, which is absent from gastric mucosa. The peroxidase has been localized mainly in parietal cells isolated and purified from gastric mucosa by controlled digestion with collagenase followed by Percoll-density-gradient centrifugation. Peroxidase activity was further localized in the outer membrane of the purified mitochondria of the parietal cell by some membrane-impermeant reagents, indicating outward orientation of the enzyme. MMI can inhibit the peroxidase activity of both the parietal cell and its mitochondria in a concentration-dependent manner. The possible involvement of the parietal-cell peroxidase-H2O2 system in MMI-induced acid secretion may be suggested.
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PMID:Localization of gastric peroxidase and its inhibition by mercaptomethylimidazole, an inducer of gastric acid secretion. 131 28

There are two types of collagenases, products of two distinct genes, called MMP-1 (matrix metalloproteinase 1 or "fibroblast-type collagenase") and MMP-8 ("neutrophil collagenase"). In synovial fluid, MMP-8 is stored as latent proenzyme in polymorphonuclear neutrophils. MMP-8 is activated by hypochlorous acid produced by myeloperoxidase from hydrogen peroxide and chloride ion and by the hydroxyl radical produced in Haber Weiss reaction fed by superoxide produced by, eg, NADPH (reduced nicotinamide adenine dinucleotide) oxidase and xanthine oxidase. In addition to activation upon secretion, oxidatively modified MMP-8 is susceptible to a subsequent proteolytic attack and activation by cathepsin G. The authors suggest that activation of neutrophil-derived MMP-8 involves oxidative, nonproteolytic activation upon secretion and a more slowly progressive proteolytic activation by cathepsin G (or chymases and tryptases), and that these oxidative and proteolytic activation mechanisms act in concert. In contrast to MMP-8, MMP-1 is synthesized de novo and secreted immediately after synthesis by fibroblasts, macrophages, and some epithelial cells. Human rheumatoid synovial tissue contains mainly fibroblast-type MMP-1 collagenase as assessed by collagenase extracted from synovial tissue and by MMP-1 and MMP-8 immunostaining. It is suggested that in vivo, MMP-1 in synovitis tissue is activated by a plasminogen activator/plasminogen/prostromelysin (alternatively tryptases)/proMMP-1 cascade. In conclusion, MMP-8 and MMP-1 show type-specific compartmentalization and modes of activation in rheumatoid synovial fluid and tissue.
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PMID:Collagenase in synovitis of rheumatoid arthritis. 141 81

Gel electrophoretic analysis of the avian tectorial membrane under non-reducing conditions reveals the presence of 2 major proteins with apparent molecular masses of 195 and 41 kDa on 8.25% gels. Under reducing conditions, 6 polypeptides with apparent molecular masses of 146, 60, 56, 43, 35 and 31 kDa are consistently observed. None of these six polypeptides observed under reducing conditions are sensitive to digestion with collagenase, and all, except for the 43 kDa component, are degraded by treatment with cold acidic pepsin. The 60, 56 and 43 kDa polypeptides bind the peroxidase conjugated lectins from Canavalia ensiformis and Triticum vulgaris, indicating the presence of mannose, N-acetyl glucosamine and/or sialic acid. The 146, 60 and 56 kDa bands undergo a shift in electrophoretic mobility after treatment of native tectorial membranes with the enzyme neuroaminidase. Fibronectin and Type II collagen cannot be detected in the avian tectorial membrane by either immunoblotting or immunofluorescence techniques. Polyclonal antisera raised against the different polypeptides after partial purification by one dimensional gel electrophoresis confirm that these proteins are all components of the tectorial membrane, and show that they are restricted to the otolithic and tectorial membranes within the inner ear. Analysis of a wide variety of other tissue types indicates that the 60, 43 and 35 kDa components can only be detected within the inner ear, and that the antisera recognising the 146 and 31 kDa components only show cross-reactivity within the head, with the anti-146 kDa antibodies staining the mucus ducts supplying the olfactory epithelium and the anti-31 kDa antibodies staining granular elements in the cells of the respiratory epithelium. The results suggest that certain of the tectorial membrane components may be novel matrix molecules unique to the inner ear, and that some of the other proteins may be antigenically related to mucins.
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PMID:The protein composition of the avian tectorial membrane. 149 Aug 98


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