Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.6.12 (chondroitinase)
 2,183 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. The hydraulic resistance of synovial interstitium helps to retain a lubricating fluid within the joint cavity. The contributions of sulphated glycosaminoglycans to resistance were assessed by selective depletion by chondroitinase ABC, keratanase and heparinases I, II and III in vivo. Also, since glycosaminoglycans do not account fully for the resistance, the contribution of non-collagenous, structural proteins in interstitium was assessed by treatment with chymopapain, a collagen-sparing protease. 2. Ringer solution containing enzyme was injected into the synovial cavity of the knee in anaesthetized rabbits. After >= 30 min the intra-articular pressure was raised and the relation between pressure (Pj) and trans-synovial outflow (Qs) determined. The slope dQs/dPj at low pressures, i.e. below yield pressure, represents the hydraulic conductance of the lining, i.e. 1/resistance. The contralateral joint received Ringer solution without enzyme as a control. Action of enzymes on the tissue was confirmed by histochemical and immunohistochemical studies. 3. Treatment with chondroitinase ABC (5 joints) increased the hydraulic conductance of the lining by 2.3 times (control, 1.34 +/- 0.22 microliter l min-1 cmH2O-1; post-enzyme, 3.11 +/- 0.45 microliter l min-1 cmH2O-1). This was significantly less than the effects of leech, Streptomyces and testicular hyaluronidases, which caused an average 4.7 times increase (P < 0.001, ANOVA). Analogous findings were made above yield pressure. 4. Treatment with keratanase (3 joints) or heparinases I, II and III (3 joints) caused no significant increase in trans-synovial flows or conductance, even though the concentration of heparan sulphate in synovium is higher than that of chondroitin sulphates or hyaluronan. 5. Treatment with chymopapain (7 joints) caused the greatest increases in trans-synovial flow, which exceeded control flow by an order of magnitude in one case. After 0.1 U chymopapain the average conductance was 6.6 times the control conductance below yield pressure. Immunohistochemical studies confirmed that chymopapain treatment removed the synovial proteoglycans. 6. It is concluded that, despite their similar resistivities in vitro, the different glycosaminoglycans do not contribute equally, weight for weight, to interstitial resistance in vivo. Hyaluronan is the dominant glycosaminoglycan governing synovial interstitial resistance. In addition, non-collagenous structural proteins contribute significantly to interstitial resistance.
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PMID:Effect of depletion of glycosaminoglycans and non-collagenous proteins on interstitial hydraulic permeability in rabbit synovium. 970 37

The presence of glycosaminoglycans (GAGs) and their contribution to mechanical properties of the cementum-dentin junction (CDJ) were investigated using nanometer scale characterization techniques. Five to two millimeter thick transverse sections from the apical ends of human molars were ultrasectioned at room temperature under wet conditions using a diamond knife and an ultramicrotome. The structure of the CDJ under dry and wet conditions before and after digestion of GAGs and collagen fibrils was studied using an atomic force microscope (AFM). The mechanical properties of the untreated and enzyme treated CDJ under wet conditions were studied using an AFM-based nanoindenter. GAG digestion was performed for 1, 3, and 5 h at 37 degrees C using chondroitinase-ABC. Collagen fibril digestion was performed for 24 and 48 h at 37 degrees C using collagenase. As reported previously, AFM scans of dry untreated CDJ (control) revealed a valley, which transformed into a peak under wet conditions. The height differences relative to cementum and dentin of untreated and treated CDJ were determined by measuring the CDJ profile under dry and wet conditions. The depth of the valley of GAG and collagen-digested CDJ was greater than that of undigested CDJ under dry conditions. The height of the peak of GAG-digested CDJ was significantly higher than that of the undigested CDJ under wet conditions. The collagen-digested CDJ under wet conditions is assumed to form a valley because of the removal of collagen fibrils from the CDJ. However, the depth of the valley was lower compared to the depth under dry conditions. Wet AFM-based nanoindentation showed that the elastic modulus and hardness of control (3.3+/-1.2 and 0.08+/-0.03 GPa) were significantly higher (ANOVA & SNK, P < 0.05) than chondroitinase-ABC treated CDJ (0.9+/-0.4 and 0.02+/-0.004 GPa) and collagenase treated CDJ (1.5+/-0.6 and 0.04+/-0.01 GPa). No significant difference in mechanical properties between chondroitinase-ABC and collagenase treated CDJ was observed. Based on the results it was concluded that the 10-50 microm wide CDJ is a composite that includes, chondroitin-4-sulfate, chondroitin-6-sulfate, and possibly dermatan sulfate, and collagen fibrils. The association of GAGs with the collagen fibrils provides the observed controlled hydration and partially contributes toward the stiffness of the CDJ under wet conditions.
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PMID:The cementum-dentin junction also contains glycosaminoglycans and collagen fibrils. 1596 5

The structural integrity of fibrillar type I collagen is critical for effective dentin bonding. Since most noncollagenous matrix components in dentin are closely associated with collagen, we hypothesized that they may also contribute to dentin bonding. To test this hypothesis, bovine dentin was acid-etched, treated with chondroitinase ABC (C-ABC), endo-beta-galactosidase (Endo-beta), or trypsin. Controls were prepared in the same manner but without the enzymes. All control and experimental specimens were then bonded with One-Step. Bond strength data were analyzed by one-way ANOVA and Fisher's PLSD test (p < 0.05). When dentin was treated with C-ABC or trypsin, bond strengths significantly decreased for the rewetted groups (p < 0.05). The treatment with Endo-beta showed no effects on bond strengths (p > 0.05). When the treated dentin surfaces were observed under SEM, the C-ABC and trypsin treated groups revealed significant loss of collagen fibril architecture. The results indicate that chondroitin sulfate glycosaminoglycans and trypsin-digestible noncollagenous proteins play roles in maintaining the open dimensions of the collagen fibril scaffold, which is essential for optimal dentin bonding.
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PMID:Removal of noncollagenous components affects dentin bonding. 1668 Jun 89