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:3.1.6.4 (chondroitinase)
2,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cocultures of rabbit fibroblasts and mouse B-16 melanoma cells produce increased levels of collagenase against type I collagen. This stimulatory effect was also found when fibroblasts were cultured in conditioned media from tumor cells. However, the level of the stimulatory factor in conditioned media was influenced by matrix deposited by fibroblasts. Thus, conditioned media collected from monolayers of B-16 plated on fibroblast matrix consistently showed high levels of the factor activity. The influence of the matrix on the level of the factor was not removed by treating the fibroblast matrix with collagenase or chondroitinase ABC and was not reproduced by collagen-coated dishes.
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PMID:Matrix influence on the tumor cell stimulation of fibroblast collagenase production. 299 20

The mineral deposits in rabbit articular cartilage induced by intra-articular injections of glucocorticoid were studied by light and electron microscopy, using histochemical techniques and x-ray-probe microanalysis. This study demonstrated that the mineral deposits consisted of hydroxyapatite crystals. The initial deposition of hydroxyapatite crystals was seen around degenerating chondrocytes, where a halo-like pericellular space contained a large amount of electron-dense amorphous material. The initial precipitation of the crystals with a low ratio of calcium to phosphorus and the subsequent growth of crystals were seen only on or within the electron-dense amorphous material until the crystals formed mature, calcified nodules. The electron-dense amorphous material frequently coexisted with proteoglycans and degenerated collagen fibers. Digestion studies using chondroitinase ABC, papain, or chloroform and methanol suggested that the electron-dense amorphous material consisted of some protein and a small amount of lipid. Matrix vesicles were rarely seen in the calcifying areas. In addition, there was a correlation between sulphur, calcium, and phosphorus in the calcifying areas, where the relative element concentrations were: S (estimation counts of sulphur) = -0.862 X (calcium counts) + 1.472 X (phosphorus counts) + 102.146. This study demonstrated that electron-dense amorphous material, proteoglycans, and degenerated collagen fibers are present in loci where the hydroxyapatite crystals are formed in articular cartilage.
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PMID:Hydroxyapatite deposition in articular cartilage by intra-articular injections of methylprednisolone. A histological, ultrastructural, and x-ray-microprobe analysis in rabbits. 300 26

We generated a monoclonal antibody (Mab) against a large chondroitin sulfate proteoglycan (CSPG) isolated from bovine aorta. This Mab (941) immunoprecipitates a CSPG synthesized by cultured monkey arterial smooth muscle cells. The immunoprecipitated CSPG is totally susceptible to chondroitinase ABC digestion and possesses a core glycoprotein of Mr approximately 400-500 KD. By use of immunofluorescence light microscopy and immunogold electron microscopy, the PG recognized by this Mab was shown to be deposited in the extracellular matrix of monkey arterial smooth muscle cell cultures in clusters which were not part of other fibrous matrix components and not associated with the cell's plasma membrane. With similar immunolocalization techniques, the CSPG antigen was found enriched in the intima and present in the medial portions of normal blood vessels, as well as in the interstitial matrix of thickened intimal lesions of atherosclerotic vessels. Immunoelectron microscopy revealed that this CSPG was confined principally to the space within the extracellular matrix not occupied by other matrix components, such as collagen and elastic fibers. These results indicate that this particular proteoglycan has a specific but restricted distribution in the extracellular matrix of arterial tissue.
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PMID:Arterial chondroitin sulfate proteoglycan: localization with a monoclonal antibody. 304 28

The immunohistological localization of chondroitin sulfate (CS) has been studied in normal and pathological human muscle. The bovine nasal cartilage proteoglycan digested with chondroitinase ABC (BNC-PG-Ch ABC) has been utilized for the production of a rabbit polyclonal antiserum. In vitro studies showed that the antiserum binds to the unsaturated disaccharide that remains attached to the core protein after digestion of the CS chains with chondroitinase ABC (Ch ABC). As the disaccharide is created specifically by Ch ABC digestion of the CS chains, the antiserum allows the immunolocalization of CS on tissue sections digested with Ch ABC. The immunohistochemical study on normal and pathological muscle demonstrated a localization of CS in all the extracellular structures: endomysium, perimysium, muscle spindle capsule and intrafusal space. In pathological conditions, the CS was raised in all the cases with increased connective tissue, showing a pattern comparable to that obtained with fibronectin and collagen III. None of the pathological conditions displayed any peculiar character of CS distribution. This finding does not support a primary role for CS in the pathogenesis of muscular dystrophy.
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PMID:Immunohistochemical localization of chondroitin sulfate in normal and pathological human muscle. 308 12

Recent results show that type IX collagen isolated from chicken cartilage is associated with one or perhaps two chondroitin sulfate chains. To locate the chondroitin sulfate chain(s) along the type IX collagen molecule, rotary shadowing was performed in the presence of monoclonal antibodies which recognize stubs of chondroitin sulfate generated after chondroitinase ABC digestion. Monoclonal antibodies 9-A-2 and 2-B-6 which recognize stubs of chondroitin 4-sulfate were found to bind specifically to the NC3 domain of type IX collagen, and this binding was dependent on prior digestion of the preparation with chondroitinase ABC. Monoclonal antibody 1-B-5, which recognizes unsulfated stubs of chondroitin sulfate, did not show any specific binding to type IX collagen either with or without chondroitinase ABC digestion. As a control, monoclonal antibody 2C2 was used, which in previous work was shown to bind specifically to an epitope located close to or at the NC2 domain. Binding of this antibody to NC2 was unaffected by chondroitinase ABC digestion, and no specific binding of the antibody to the NC3 domain was detected either before or after chondroitinase ABC digestion.
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PMID:Use of monoclonal antibodies to locate the chondroitin sulfate chain(s) in type IX collagen. 309 5

Changes in the structure and organization of collagen fibrils were recently described in the skin of aspartylglycosaminuria patients. The skin of the patients contained a normal amount and distribution of glycosaminoglycans, but the dermatan sulfate of aspartylglycosaminuria skin was more sensitive to chondroitinase AC digestion, resulting in unsaturated 4-sulfated disaccharides which were not detected in controls. Isolated dermatan sulfate chains as well as the chains present in the intact core protein synthesized by skin fibroblasts from an aspartylglycosaminuria patient were also digestible with chondroitinase AC, while those of a control fibroblast culture could be digested with chondroitinase ABC only. This is indirect evidence for abnormal epimerization of dermatan sulfate in the skin of aspartylglycosaminuria patients, which may be associated with the changes in collagen fibril formation.
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PMID:Abnormal dermal proteoglycan in aspartylglycosaminuria: a possible mechanism for ultrastructural changes of collagen fibrils in a glycoprotein storage disorder. 313 50

Human collagen type IX was isolated from the media of organ cultures of fetal or infant hyaline cartilage. It consisted of three distinct, disulfide-bonded polypeptides of 115, 84, and 72 kDa, respectively. Digestion with chondroitinase ABC reduced the apparent molecular mass of the 115-kDa chain to about 65 kDa demonstrating that also human collagen type IX is a proteoglycan. In the electron microscope, the molecule had a rigid rod-like structure with characteristic kinks and with a globular domain at one end. Digestion of human collagen type IX with pepsin leads to somewhat heterogeneous fragments. Affinity-purified antibodies to the mixture of fragments specifically reacted with the fragment HMW without cross-reaction with chicken HMW. LMW of both species were recognized to the same low extent. Mechanically generated fibril fragments from human fetal cartilage were heterogeneous in diameter. Significantly, they could be immunostained for collagen type IX in a D-periodic pattern and regardless of the fibril diameter. Some fibrils were poorly labeled, again independently of the diameter. Therefore, the role of collagen type IX in cartilage probably is not to control directly the lateral growth during fibrillogenesis but rather to stabilize the fibril network.
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PMID:The structure of human collagen type IX and its organization in fetal and infant cartilage fibrils. 314 13

Proteodermatan sulfate was isolated from the skin of human, female breast in 6-M urea and proteolytic inhibitors at 70 degrees C and purified on Sephacryl S-200. It was composed of 55% protein and 45% dermatan sulfate, displayed one protein and carbohydrate-stainable band on agarose-polyacrylamide gels, yielded dermatan sulfate after digestion by papain, and its calculated E0.1% 1 cm, 280 nm was 16.2. Its mucopolysaccharide portion was digested by chondroitinase ABC but not by chondroitinase AC. This proteoglycan was used to immunize rabbits. Double diffusion of antiserum against the antigen or its core protein resulted in one precipitation band. Antiserum did not cross-react with bovine collagen type I, human fibronectin, dermatan sulfate, hyaluronic acid, heparin, heparan sulfate or the chondroitin sulfates by double diffusion. The antiserum titer determined by radioimmunoassay was 1:16,000. This assay was not affected by a 40-fold excess of dermatan sulfate. Purified IgG molecules were apparently associated with collagen in human breast mid-dermis as demonstrated by indirect immunoelectron microscopy with ferritin-labeled goat antirabbit IgG. The results indicate that rabbit anti-human, anti-proteodermatan sulfate IgG is highly specific for the core protein of dermatan sulfate and confirm the hypothesis that in vivo proteodermatan sulfate is closely associated with collagen.
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PMID:Immunoelectron microscopy of proteodermatan sulfate in human mid-dermis. 315 40

Heparan sulfate and heparin, two sulfated glycosaminoglycans (GAGs), extracted collagen-tailed acetylcholinesterase (AChE) from the extracellular matrix (ECM) of the electric organ of Discopyge tschudii. The effect of heparan sulfate and heparin was abolished by protamine; other GAGs could not extract the esterase. The solubilization of the asymmetric AChE apparently occurs through the formation of a soluble AChE-GAG complex of 30S. Heparitinase treatment but not chondroitinase ABC treatment of the ECM released asymmetric AChE forms. This provides direct evidence for the vivo interaction between asymmetric AChE and heparan sulfate residues of the ECM. Biochemical analysis of the electric organ ECM showed that sulfated GAGs bound to proteoglycans account for 5% of the total basal lamina. Approximately 20% of the total GAGs were susceptible to heparitinase or nitrous acid oxidation which degrades specifically heparan sulfates, and approximately 80% were susceptible to digestion with chondroitinase ABC, which degrades chondroitin-4 and -6 sulfates and dermatan sulfate. Our experiments provide evidence that asymmetric AChE and carbohydrate components of proteoglycans are associated in the ECM; they also indicate that a heparan sulfate proteoglycan is involved in the anchorage of the collagen-tailed AChE to the synaptic basal lamina.
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PMID:Anchorage of collagen-tailed acetylcholinesterase to the extracellular matrix is mediated by heparan sulfate proteoglycans. 316

Low molecular mass proteoglycans (PG) were isolated from human articular cartilage and from pig laryngeal cartilage, which contained protein cores of similar size (Mr 40-44 kDa). However, the PG from human articular cartilage contained dermatan sulphate (DS) chains (50% chondroitinase AC resistant), whereas chains from pig laryngeal PG were longer and contained only chondroitin sulphate (CS). Disaccharide analysis after chondroitinase ABC digestion showed that the human DS-PG contained more 6-sulphated residues (34%) than the pig CS-PG (6%) and both contained fewer 6-sulphated residues than the corresponding high Mr aggregating CS-PGs from these tissues (86% and 20% from human and pig respectively). Cross-reaction of both proteoglycans with antibodies to bovine bone and skin DS-PG-II and human fibroblasts DS-PG suggested that the isolated proteoglycans were the humans DS-PG-II and pigs CS-PG-II homologues of the cloned and sequenced bovine proteoglycan. Polyclonal antibodies raised against the pig CS-PG-II were shown to cross-react with human DS-PG-II. SDS/polyacrylamide-gel analysis and immunoblotting of pig and human cartilage extracts showed that some free core protein was present in the tissues in addition to the intact proteoglycan. The antibodies were used in a competitive radioimmunoassay to determine the content of this low Mr proteoglycan in human cartilage extracts. Analysis of samples from 5-80 year-old humans showed highest content (approximately 4 mg/g wet wt.) in those from 15-25 year-olds and lower content (approximately 1 mg/g wet wt.) in older tissue (greater than 55 years). These changes in content may be related to the deposition and maintenance of the collagen fibre network with which this class of small proteoglycan has been shown to interact.
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PMID:Dermatan sulphate proteoglycan from human articular cartilage. Variation in its content with age and its structural comparison with a small chondroitin sulphate proteoglycan from pig laryngeal cartilage. 319 90


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