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)

Using EDTA extraction and collagenase digestion, cancellous bone from the femoral heads of ten normal and eight osteoarthrotic individuals was analyzed for its content of collagen, sialoprotein, proteoglycan, and carbohydrate. The EDTA extractability of the matrix proteins of the osteoarthrotic bone was significantly increased (P less than 0.001), as was the soluble collagenase-resistant fraction (SCRF). EDTA residues, bone matrix size, the collagenase-resistant fraction (CRF), and the insoluble collagenase-resistant fraction (ICRF) of the osteoarthrotic cases were not different from those of the controls. The amounts of carbohydrate and proteoglycans were considerably elevated in the bone matrix of the osteoarthrotic bone (P less than 0.01 and P less than 0.001, respectively). In the EDTA extracts, sialoprotein and proteoglycan contents were found in significant higher amounts (P less than 0.05 and P less than 0.01, respectively) in the osteoarthrotic cases. In the SCRF, the hexose and sialic acid contents were higher in the osteoarthrotic bone (P less than 0.01), while in the ICRF all the analyses were significantly increased in the osteoarthrotic bone (P less than 0.001). The ratios of collagen to non-collagenous components were lower in the osteoarthrotic than in normal bones. The quantitative and qualitative variations in cancellous bone proteins from the femoral head in osteoarthrosis found in this study suggest that alterations in subchondral bone play a role in the pathophysiology of cartilage degeneration in osteoarthrosis.
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PMID:Chemical composition of normal and osteoarthrotic cancellous bone of the femoral head. Studies of EDTA extracts and collagenase digests. 671 29

A detailed dose-response study relating mannose and glucose oxidation with the induction of 45Ca uptake and insulin release was performed using in vitro incubation of collagenase digested rat islets of Langerhans. The threshold value for 14C-U-D-glucose oxidation, glucose-stimulation of 45Ca uptake, and insulin release was about 5.5 mM. The half maximal response for these 3 parameters occurred at 13.4 mM, 11.6 mM, and 12.2 mM, respectively. Their maximal responses were obtained at approximately 20 mM. The threshold level for mannose oxidation, induction of 45Ca uptake and insulin release was about 11.0 mM, with half maximal responses obtained at 24.6 mM, 20.5 mM, and 22.2 mM, respectively. The maximum response of the 3 parameters to mannose was obtained at 38.8 mM and appeared to reach the same level obtained for glucose. These results suggest that hexose degradation has a significant role in controlling Ca uptake and subsequent insulin release. A lower rate of mannose oxidation appeared to account for its weaker stimulating efficacy for Ca uptake and insulin release.
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PMID:Metabolism, 45Ca uptake and insulin releasing capacities of glucose and mannose. 699 61

The characterization of cytochalasin B binding and the resulting effect on hexose transport in rat liver parenchymal cells in primary culture were studied. The cells were isolated from adult rats by perfusing the liver in situ with collagenase and separating the hepatocytes from the other cell types by differential centrifugation. The cells were established in primary culture on collagen-coated dishes. The binding of [4-3H]cytochalasin B and transport of 3-O-methyl-D-[14C]glucose into cells were investigated in monolayer culture followed by digestion of cells and scintillation counting of radioactivity. The binding of cytochalasin B to cells was rapid and reversible with association and dissociation being essentially complete within 2 min. Analysis of the kinetics of cytochalasin B binding by Scatchard plots revealed that binding was biphasic, with the parenchymal cell being extremely rich in high-affinity binding sites. The high-affinity site, thought to be the glucose-transport carrier, exhibited a KD of 2.86 x 10(-7) M, while the low-affinity site had a KD of 1.13 x 10(-5) M. Sugar transport was monitored by 3-O-methyl-D-glucose uptake and it was found that cytochalasin B (10(-5) M) drastically inhibited transport. However, D-glucose (10(-5) M) did not displace cytochalasin B, and cytochalasin E, which does not inhibit transport, was competitive for cytochalasin B at only the low-affinity site, demonstrating that the cytochalasin B inhibition of sugar transport occurs at the high-affinity site but that the inhibition is non-competitive in nature. Therefore, the liver parenchymal cells may represent an unusually rich source of glucose-transport system which may be useful in the isolation of this important membrane carrier.
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PMID:Characterization of cytochalasin B binding to adult rat liver parenchymal cells in primary culture. 743 25

Mouse mannan-binding protein (MBP) was identified in serum by its Ca(2+)-dependent binding to mannan. On gel permeation chromatography, the protein eluted corresponding to a molecular weight of approximately 750 kDa. Analysed on SDS-PAGE under reducing conditions, the polypeptide showed an apparent molecular weight of 28 kDa, while several high molecular weight bands were seen under non-reducing conditions. The presence of collagen-like domains within the molecule was indicated by a high glycine content (14.9%) and substantiated by sensitivity to collagenase. Rabbit anti-mouse MBP antisera were raised. The concentration of MBP in serum from normal mice was measured by rocket immunoelectrophoresis and found to be from below 1 microgram/ml to 100 micrograms/ml (average 50 micrograms/ml, n = 60). The binding of mouse MBP to mannan could be inhibited by mono- and disaccharides in the following order of potency: L-fucose > D-mannose > N-acetyl-D-glucosamine > maltose > D-mannoheptulose > D-glucose > N-acetyl-D-mannosamine >> lactose > D-galactose >> N-acetyl-D-galactosamine. Mouse MBP was shown to activate the classical complement cascade after binding to mannan. The sequence of 14 NH2-terminal amino acid residues of the molecule showed 93% identity to rat MBP-A and complete identity to the translated cDNA sequences for mouse MBP-A and mouse Ra-reactive factor component P28b (RaRF P28b) published previously. The amino acid composition of mouse MBP showed a high degree of homology to MBPs from other species and mouse RaRF P28b.
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PMID:Purification and characterization of mannan-binding protein from mouse serum. 829 64

The authors report on the purification and characterization of mannan- binding proteins (MBP) isolated from porcine serum. The MBPs were purified by use of PEG precipitation, affinity chromatography on mannan-Sepharose, protein A- and anti-porcine IgM-Sepharose followed by gel filtration. The MBP proteins were collagenase sensitive and showed gamma 1-gamma 2-electrophoretic mobility. The MBP designated pMBP-28 had a molecular mass of 28 kDa when analysed on SDS-PAGE under reducing conditions and eluted corresponding to a molecular mass of approximately 700 kDa on gel filtration chromatography. Electron micrographs of pMBP-28 revealed an oligomeric protein similar to rodent MBP-A and human MBP but with a predominance of penta- and hexameric molecules. Another protein designated pMBP-27 was composed of peptides of 27 kDa and had an Mr of 300-350 kDa on gel filtration chromatography. Electron microscopy of pMBP-27 showed dimer and trimer molecules; the trimers without distinct stalk regions. The N-terminal 26(pMBP-27) and 24(MBP-28) amino acid residues showed 54% and 58% identity with human MBP.pMBP-28 showed a higher degree of sequence similarity to rat and mouse MBP-A (60% identity) than to mouse and rat MBP-C (41-45% identity). Both pMBPs exhibited Ca2+-dependent binding to D-mannose immobilized on agarose but no significant binding to N-acetyl-D-glucosamine- or fucose-agarose. The results further suggested the presence of a third pMBP which copurified with pMBP-27 but this protein was not sequenced.
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PMID:Isolation and characterization of porcine mannan-binding proteins of different size and ultrastructure. 860 63

The present study investigated the glycosylation state of proteins in lung tissue of a cyclophosphamide-induced model of pulmonary fibrosis in rats. In fibrotic lung, the carbohydrate constituents (total hexose, fucose, sialic acid and hexosamine) of salt-soluble, collagenase, elastase and papain digested glycoproteins were significantly higher compared to normal lungs. Interestingly, fibrotic lung tissues had higher activities of mannosyl, glucosyl, galactosyl, sialyl and fucosyl transferases than normal lung tissues. Similarly, mannosyl, glucosyl, galactosyl, sialyl and fucosyl transferases were higher in serum from rats with fibrosis than in that from normals. These data indicate that glycoprotein metabolism is significantly altered from normal in animals with interstitial lung fibrosis.
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PMID:Glycoprotein composition in cyclophosphamide-induced lung fibrosis. 968 8

Methods have been developed for producing functional, transporting monolayers of avian proximal tubule (PT) cells. A highly homogenous fraction of PT fragments was prepared by enzymatic digestion (collagenase + Dispase) of chick (3- to 5-day-old) kidneys, followed by Percoll gradient centrifugation. The PT fraction was enriched in glucose-6-phosphatase, a proximal enzyme marker, and reduced in specific activity of hexokinase, a distal marker. PT fragments were grown to confluence in serum-free media on collagen-coated permeable filter supports. Electron microscopy of confluent monolayers revealed numerous microvilli and mitochondria, central cilia, and tight junctions, all characteristic of PT cells. gamma-Glutamyltranspeptidase, a proximal brush-border enzyme, showed threefold higher activity on apical than on basolateral sides of the monolayer. The electrophysiological characteristics of monolayers were investigated by voltage-clamp techniques. Monolayers displayed low transepithelial resistances (40-60 Omega . cm2), lumen-negative potentials, and baseline currents of 6-12 microA/cm2 (with or without 5 mM glucose). Both alpha-methyl-D-glucose (2 mM), a nonmetabolizable hexose, and phenylalanine (2 mM) significantly stimulated short-circuit current when added to the mucosal side of glucose-free monolayers. Phloridzin, a specific inhibitor of Na+-coupled glucose transport, significantly inhibited short-circuit current, as did 10(-5) M amiloride. Monolayers also expressed net secretory transport of urate. This cell culture preparation may provide a useful working model for the study of avian PT transport.
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PMID:Characterization of a primary cell culture model of the avian renal proximal tubule. 968 82

The present investigation was designed to characterize the biochemical and connective tissue components and to correlate the significance of morphological and biochemical perturbations in cyclophosphamide (CP)-induced lung fibrosis in rats. Lung fibrosis was induced in male Wistar rats by intraperitoneal injection of 20 mg/100 g body weight of CP, and their pneumotoxic derangements were characterized during an early destructive phase followed by a proliferative and synthetic phase. Serum angiotensin-converting enzyme (ACE) activity was higher in CP-treated rats at days 2, 3, 5, 7, and 11, but there was a significant decrease in lung ACE activity during the same time period. Elevated levels of beta-glucuronidase activity were observed in the lung lavage fluid of CP-administered rats days 2, 3, 5, and 7. Lung myeloperoxidase activity was higher in CP rats. Of significance was the presence of collagenase and collagenolytic cathepsin in the lavage fluid of CP rats, when compared with the barely detectable levels in controls. A similar increase in these enzyme activities was also noticed in the lung tissue of CP rats during the same experimental period. Lavage fluid hydroxyproline content was higher in CP rats when compared with controls. Similarly, lung protein and DNA levels were elevated significantly after treatment with CP. The pulmonary histamine and serotonin contents were significantly higher in CP rats. The incorporation of [3H]thymidine into lung total DNA, [3H]proline into lung hydroxyproline, and [35S]sulphate into lung glycosaminoglycan, measured as indicators of lung DNA, collagen, and glycosaminoglycan synthesis, respectively, was also higher in CP groups. Increased levels of hydroxyproline, elastin, hexosamine, total hexose, fucose, sialic acid, and uronic acid in the lungs of rats 14, 28, and 42 days after CP insult were characterized as biomarkers of CP-induced interstitial changes. These findings indicate that CP-induced lung fibrosis results in alterations not only in collagen synthesis and accumulation, but also in glycosaminoglycan and glycoprotein content.
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PMID:Biochemical and connective tissue changes in cyclophosphamide-induced lung fibrosis in rats. 977 51

The effects of three-month dietary xylitol supplementation on the amounts and hexose contents of acid-soluble collagen as well as on the amounts and fluorescence of collagenase-soluble collagen were studied in healthy and streptozotocin-diabetic male rats. Collagen was extracted from skin samples. In the healthy rats, supplementation with xylitol (10%) increased the hydroxyproline content of the acid-soluble fraction and skin thickness. In diabetic rats receiving and not receiving xylitol, the acid-soluble collagen fraction was markedly lower than in healthy rats. However, its amount was significantly elevated when xylitol had been added to the diet. Supplementation with xylitol caused no changes in the amounts of collagenase-soluble fraction in either healthy or diabetic rats. Supplementation with xylitol (10%) significantly decreased the hexose content of acid-soluble collagen and the fluorescence of the collagenase-soluble fraction in both healthy and diabetic rats. The results indicate that dietary xylitol affects collagen synthesis and collagen glycosylation.
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PMID:Effects of dietary xylitol on collagen content and glycosylation in healthy and diabetic rats. 1098 72

Human mannan binding lectin (MBL) is a member of the collectins, a group of proteins that contain a dual structure with a lectin and a collagenous moieties. The collectins are considered as major actors of innate immunity. We report the presence of low molecular weight intracellular MBL forms in human hepatocytic cell lysates, with binding capacities associated to its lectin and/or its collagen moiety. Competition with D-mannose and with antibodies directed against the lectin binding site of MBL indicate that the 60 kDa form represents an intracellular association of MBL through its lectin moiety. The effects of collagenase or MBL associated serine proteases (MASPs) from a MBL deficient plasma, gave evidence that the 60 KDa form contains also collagen and suggested the binding of a ligand to this collagen part. These results show that this intracellular form of MBL shares binding properties with circulating MBL. The binding potential of the lectin and the collagenous parts of precursor forms of intracellular MBL may suggest that they behave as molecular chaperone. The complexity of MBL structure and functions deserves further investigation on other intracellular forms of MBL.
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PMID:Analysis of low molecular weight intracellular associations of a human mannan binding lectin (MBL). 1468 36


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