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:3.2.1.31 (beta-glucuronidase)
7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Leupeptin, antipain, tosyl-lysylchloromethane (Tos-Lys-CH2Cl) and benzyloxy-carbonylphenylalanylalanyldiazomethane (Z-Phe-Ala-CHN2) inhibit reversibly the resorption induced by parathyroid hormone or heparin in cultured mouse bones. Leupeptin and antipain do not affect collagenase production and activity or the enhanced secretion of beta-glucuronidase induced by the bone-resorbing agents. They might thus act by a direct (extracellular?) inhibition of lysosomal thiol proteinases.
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PMID:Inhibition of bone resorption in culture by inhibitors of thiol proteinases. 627 2

Whole isolated rat glomeruli (WG) were incubated with bacterial collagenase to separate epithelial cells (EC) from the cores of glomerular tufts (GC), which consisted of mesangial and endothelial cells, as demonstrated by electron microscopy. Lysates of WG, EC, and GC and of renal tubules were prepared by hypo-osmotic shock and freeze-thawing. Activities of the following acidic lysosomal hydrolases were measured: acid phosphatase, beta-glucuronidase, cathepsin-D, non-specific esterase, and aryl sulfatases A and B. The glomerular cell preparations showed activities of all studied enzymes. GC had higher activities than EC, save for nonspecific esterase. Studies of the recovery of acid phosphatase and beta-glucuronidase revealed that approximately 2/3 of the hydrolase activities present in WG was still measureable after collagenase treatment and that the bulk of this was found in the GC lysates. These findings demonstrate that the rat glomerulus and its cell components have considerable biochemical activities of acidic hydrolytic enzymes. These appear to be most prominent in the combined mesangial and endothelial cells of the GC components.
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PMID:Lysosomal enzymes in glomerular cells of the rat. 628 26

Dispersed cells from human amnion and chorion were cultured with and without relaxin. The addition of this hormone caused an increased secretion of both collagenase and plasminogen activator into the culture medium over a 32 h period, but had no effect on proteoglycanase or beta-glucuronidase secretion. The increase in plasminogen activator was dose-related to the amount of relaxin added in vitro. The results show that the fetal membranes are a novel target tissue for relaxin in the human, and suggest that relaxin in vivo may cause a similar release of collagenolytic enzymes, leading to the weakening and eventual rupture of the fetal membranes.
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PMID:Relaxin stimulates collagenase and plasminogen activator secretion by dispersed human amnion and chorion cells in vitro. 630 28

Synthetic hydroxyapatite (HA) and calcium pyrophosphate dihydrate (CPPD) microcrystals are phagocytosed by rabbit articular-cartilage chondrocytes in primary culture. The ingestion of crystals greatly stimulated the release of collagenase, neutral protease, and prostaglandins E2 and F2 alpha into the ambient medium. Lactate dehydrogenase was not released by either crystal despite electron microscopic evidence of cell damage by HA crystals (partial loss of phagolysosomal membrane and increased myelin figures). HA, but not CPPD crystals, stimulated release of beta-glucuronidase. HA crystal concentrations from 50 to 200 micrograms ml-1 induced a dose-dependent release of collagenase and of extracellular protein. Both phagocytosis and collagenase release were greatly attenuated when HA crystals were added to the chondrocyte monolayers in the absence of serum. As HA and CPPD crystals have been identified in human articular cartilage in association with degenerative changes, it is possible that the cell-crystal interaction described here may be pathogenetically important.
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PMID:Phagocytosis of hydroxyapatite or calcium pyrophosphate dihydrate crystals by rabbit articular chondrocytes stimulates release of collagenase, neutral protease, and prostaglandins E2 and F2 alpha. 630 68

The activity of collagenase and certain lysosomal hydrolases (cathepsin B1, cathepsin D, beta-glucuronidase and beta-N-acetyl glucosaminidase) was studied in serum and tissues of rats with streptozotocin- or alloxan-induced diabetes. The activity of serum lysosomal enzymes was increased in both groups (p less than 0.05). Both streptozotocin- and alloxan-diabetic animals showed significantly higher dermal collagenase activity than those of controls (p less than 0.01), but the liver and spleen showed similar activities; there was a significant decrease in the renal collagenase activity of streptozotocin-diabetic rats (p less than 0.05). Comparison of the alloxan- or streptozotocin-treated groups with control animals showed an increase in lysosomal enzymes (cathepsin B1, cathepsin D, beta-glucuronidase and beta-N-acetyl glucosaminidase in skin, liver and spleen) (p less than 0.05) but beta-N-acetyl glucosaminidase was unchanged in the spleen of streptozotocin-diabetic rats. There was no difference in renal cathepsin B1 and D in control versus alloxan-diabetic rats, but there was an increase in beta-glucuronidase and beta-N-acetyl glucosaminidase (p less than 0.05). The streptozotocin-diabetic animals showed decreased activities of renal lysosomal enzymes (p less than 0.05), but similar activity of cathepsin D to the control animals.
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PMID:Influence of streptozotocin- and alloxan-induced diabetes in the rat on collagenase and certain lysosomal enzymes in relation to the degradation of connective tissue proteins. 630 89

Human synovial fluid often contains small cartilaginous "wear particles." Previous in vitro experiments have indicated the potential involvement of these particles in the pathophysiology of arthritis. To determine whether this potential is realized under the conditions existing within joints, standard suspensions of lapine articular cartilage were injected intraarticularly into the knee joints of rabbits. Thrice-weekly injections of 1 mg allogenic cartilage produced an inflammatory arthritis, accompanied by a marked cellular effusion, in all rabbits within 5 months. The synovium became hyperplastic, discolored, and infiltrated with mononuclear inflammatory cells. Embedded particles of the injected material were seen in histologic preparations of these synovia. Organ cultures of such synovia produced 4 to 5 times more collagenase, plasminogen activator, "Pz-peptidase," neutral and acid azocaseinase, and beta-glucuronidase than did cultures of synovia from control knees injected with saline. Furthermore, the articular cartilage of knees injected with cartilaginous particles showed elevated intrinsic collagenolytic activity. Histologic examination of the articular cartilage revealed an attendant loss of metachromasy, resulting in friability, pitting, and discoloring of the cartilage. Preliminary immunoassays failed to demonstrate a systemic immune response to the injected material.
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PMID:Experimental arthritis induced by intraarticular injection of allogenic cartilaginous particles into rabbit knees. 632 Aug 35

We describe the effects of products of mononuclear phagocytes on the secretory activity of chondrocytes. The primary confluent cultures of rabbit articular chondrocytes were exposed to standard medium alone or enriched with conditioned medium obtained from cultures of rabbit peritoneal macrophages, the mouse macrophage cell line P388D1 or human blood mononuclear cells. Four markers of release were assessed, the neutral proteinases plasminogen activator and collagenase, the acid hydrolase beta-glucuronidase and prostaglandin E2, and the kinetics of their changes were monitored. Chondrocytes that were cultured in standard medium secreted large amounts of plasminogen activator, some beta-glucuronidase, but no collagenase, and released only minor amounts of prostaglandin E2. The addition of conditioned medium from rabbit macrophages induced a rapid release of large quantities of prostaglandin E2 and an abundant secretion of collagenase, while abolishing or strongly decreasing plasminogen activator secretion. In addition, beta-glucuronidase secretion was markedly enhanced. The decrease in secretion of plasminogen activator appeared to reflect a diminished production, since no evidence was found for the generation of inhibitors or for an accelerated extracellular breakdown of the enzyme. Conditioned media of the mouse and human mononuclear cells influenced the secretory activities of rabbit articular chondrocytes in a similar way, suggesting that the factor (or factors) acting on chondrocytes is produced by a variety of macrophages, and that its action is not species-restricted. The time course and concentration-dependence of the effects observed indicate that the secretion of plasminogen activator and collagenase are influenced in a strictly reciprocal fashion by the macrophage products. The release of prostaglandin E2 paralleled that of collagenase.
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PMID:Influence of macrophage products on the release of plasminogen activator, collagenase, beta-glucuronidase and prostaglandin E2 by articular chondrocytes. 633 94

The cellular localization of indoleamine 2,3-dioxygenase was studied in the mouse lung after induction by lipopolysaccharide treatment. No significant indoleamine 2,3-dioxygenase activity was detected in alveolar macrophages and type II epithelial cells, which were recovered by alveolar lavages and trypsin-treatment, respectively. To determine this enzyme activity in other types of lung cells, we prepared monodispersed lung cells (6.5 X 10(7) cells/lung) by incubation with 0.1% collagenase and 0.1% trypsin. In a Percoll isopycnic gradient, the dispersed cells were distributed with two peaks at the densities of 1.040 and 1.080 g/ml. The enzyme activity was recovered exclusively in the lighter fractions. As examined by electron microscopy or more quantitatively by using various marker enzyme activities, endothelial cells (angiotensin-converting enzyme as a marker enzyme of these cells), alveolar interstitial cells (prostaglandin dehydrogenase), type I epithelial cells, type II epithelial cells, alveolar macrophages (beta-glucuronidase), Clara cells (coumarin hydroxylase), and polymorphonuclear leucocytes (arylsulfatase) were distributed with peaks at the densities of 1.033, 1.040, 1.042, 1.045, 1.070, 1.082, and 1.093 g/ml, respectively. The distribution pattern of the indoleamine 2,3-dioxygenase activity exactly coincided with that of alveolar interstitial cells. The localization of this enzyme in alveolar interstitial cells was immunohistochemically confirmed with the anti-indoleamine 2,3-dioxygenase antibody.
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PMID:Induction of indoleamine 2,3-dioxygenase in alveolar interstitial cells of mouse lung by bacterial lipopolysaccharide. 634 79

The mononuclear cell fraction of rat hind-limb muscle was obtained by digestion with clostridial collagenase in the presence of calcium ions, filtration through nylon screens and washing to remove the enzyme. Final traces of contaminant myofibrillar debris were separated by isopycnic centrifugation in a Percoll density gradient. Whole muscle, washed cells and Percoll-fractionated cells were extracted in the presence of non-ionic detergent and the supernatants assayed for the lysosomal enzymes cathepsins B + L, N-acetyl-beta-glucosaminidase, beta-glucuronidase and protein. The enzyme levels were highest in the muscle from young rats, but the percentage of recovered activity in the mononuclear cell fraction was little altered by the age of the animal. The values obtained were: cathepsin B + L, 2.4-4.0%; N-acetyl-beta-glucuronidase, 4.3-7.6%; and beta-glucuronidase, 6.3-10.3%. Because of unavoidable losses in preparation these are minimal values and the actual levels of activity from the mononuclear cell fraction in muscle would be higher. The specific activity values of the cell lysates were raised after isopycnic centrifugation and were nearly constant over the age range 65-180 days. Substantially higher specific activity values were obtained for the cells from rats of 38 days. When grown in culture the mononuclear cell fractions were seen to contain mainly fibroblasts and myoblasts with only few leucocytes. The cultures reached confluence by the second week, at which time numerous myotubes had formed. In addition there were groups of large, circular cells with a prominent centrosphere. The origin of these latter cells is uncertain. It was concluded that although total lysosomal enzyme activity was higher in young rats there was little effect of age on the distribution of activity between muscle fibres and mononuclear cells in the muscle.
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PMID:The mononuclear cell population in rat leg muscle: its contribution to the lysosomal enzyme activities of whole muscle extracts. 718 82

We have compared the effects of a general matrix metalloproteinase (MMP) inhibitor (CT435) with those of a concentration-dependent specific gelatinase inhibitor (CT543; Ki < 20 nM) on bone resorption in vitro. The test systems consisted of measuring: (i) the release of 45Ca2+ from prelabelled mouse calvarial explants; (ii) the release of 45Ca2+ from prelabelled osteoid-free calvarial explants co-cultured with purified chicken osteoclasts; and (iii) lacunar resorption by isolated rat osteoclasts cultured on ivory slices. Both CT435 and CT543 dose-dependently inhibited the release of 45Ca2+ from neonatal calvarial bones stimulated by either parathyroid hormone or 1,25-dihydroxyvitamin D3. Moreover, CT543 produced a 40% inhibition at a concentration (10(-8) M) selective for the inhibition of human gelatinases A and B. CT435 (10(-5) M) and CT543 (10(-5) M) partially inhibited the release of 45Ca2+ from osteoid-free calvarial explants by chicken osteoclasts with a maximum of approximately 25% for unstimulated cultures, and approximately 36% for cultures stimulated by interleukin-1 alpha (IL-1 alpha; 10(-10) M). Neither inhibitor prevented lacunar resorption on ivory by unstimulated rat osteoclasts, but the compounds produced a partial reduction in both the number and total surface area of lacunae in IL-1 alpha-stimulated cultures, with maximal action at 10(-5) M. Neither of the inhibitors affected protein or DNA synthesis, nor the IL-1 alpha-stimulated secretion of the lysosomal enzyme beta-glucuronidase. Immunocytochemistry demonstrated that isolated rabbit osteoclasts constitutively expressed gelatinase A and synthesized gelatinase B, collagenase and stromelysin, as well as the tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) following IL-1 alpha stimulation. These experiments have shown that in addition to collagenase, gelatinases A and B are likely to play a significant role in bone resorption. They further suggest that MMPs produced by osteoclasts are released into the sub-osteoclastic resorption zone where they participate in bone collagen degradation.
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PMID:The effects of selective inhibitors of matrix metalloproteinases (MMPs) on bone resorption and the identification of MMPs and TIMP-1 in isolated osteoclasts. 769 5


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