Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: DrugBank:APRD00216 (ABC)
 8,859 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The extracellular sulfated glycosaminoglycans synthesized by explants of rabbit cornea and sclera, and by confluent cultures of corneal fibroblasts after incubation in medium containing 35S-sulfate were compared. The glycosaminoglycans isolated from corneal explants differed considerably from those obtained from confluent corneal fibroblast cultures and scleral explants. Only the corneal explants secreted into the nutrient medium a population of enzyme-resistant 35S-sulfate-labeled glycosaminoglycan that eluted from Dowex 1-X2 (Cl-) at a 3 M sodium chloride concentration, and which was resistant to testicular hyaluronidase, chondroitinase ABC, and nitrous acid degradation. With time, corneal explants gradually synthesized less of this fraction with these attributes of keratosulfate. If the corneal epithelium and endothelium remained on the corneal explants the total incorporated 35S-sulfate was approximately double that obtained when the cornea was striped of these cells.
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PMID:A comparative study of extracellular sulfated glycosaminoglycans synthesized by rabbit corneal fibroblasts in organ and confluent cultures. 13 75

The glomerular basement membrane was subjected to digestion with specific enzymes to determine the chemical nature (sialoglycoproteins, collagenous peptides, or glycosaminoglycans) of the anionic sites previously demonstrated in the laminae rarae. Enzyme digestion was carried out both in situ and in vitro. Kidneys were perfused in situ with enzyme solutions followed by perfusion with fixative containing the cationic dye, ruthenium red, to detect the anionic sites. Glomerular basement membranes were isolated by detergent treatment of glomeruli and incubated with enzyme solutions, followed by incubation with cationized ferritin (pI 7.3-7.5) to label the anionic sites. Only highly purified enzymes free of proteolytic activity were used. The findings were the same both in situ and in vitro. The anionic sites were unaffected by treatment with neuraminidase, chondroitinase ABC, and testicular or leech hyaluronidase. However, they could no longer be demonstrated after digestion with crude heparinase, purified heparitinase, or Pronase or after nitrous acid oxidation. The results demonstrate that the sites contain heparan sulfate since they are removed by treatment with heparitinase and by nitrous acid oxidation-procedures specific for heparan sulfate; and that sialoglycoproteins or other glycosaminoglycans do not represent major components of these sites since the latter are not affected by digestion with neuraminidase and other glycosaminoglycan-specific enzymes. Identical findings were obtained on basement membranes in other locations (Bowman's capsule, tubule epithelium, and endothelium of peritubular capillaries). The presence of heparan sulfate in the glomerular basement membrane is discussed in relation to the charge-selective properties of the glomerular filter and in relation to its potential involvement in various types of glomerular injury.
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PMID:Presence of heparan sulfate in the glomerular basement membrane. 15 19

Glycosaminoglycans were isolated from purified fractions of glomerular basement membranes and partially characterized by chemical analysis and cellulose acetate electrophoresis. Basement membranes were prepared by detergent treatment of rat glomeruli and subjected to digestion with papain and Pronase. Glycosaminoglycans were isolated from the digests by precipitation with cetyl pyridinium chloride and ethanol. Results of cellulose acetate electrophoresis of the isolated glycosaminoglycan fraction revealed the presence of one major and one minor spot. The major spot was identified as heparan sulfate because it comigrated with the heparan sulfate standard and was sensitive to heparinase and to nitrous acid oxidation but insensitive to chondroitinase ABC and to testicular or leech hyaluronidase. The minor spot was tentatively identified as hyaluronic acid based on its migratory behavior and sensitivity to leech and testicular hyaluronidase. The chemical composition of the isolated glycosaminoglycan was typical of that of heparan sulfate (high carbazole/orcinol ratio, high sulfate content, absence of galactosamine). The data support and confirm the cytochemical data obtained previously [Kanwar, Y. S. & Farquhar, M. G. (1979) Proc. Natl. Acad. Sci. USA 76, 1303-1307] demonstrating that heparan sulfate is the only sulfated glycosaminoglycan detectable in the glomerular basement membrane. The present results suggest that in addition to sulfated glycosaminoglycan some nonsulfated glycosaminoglycan (hyaluronic acid) may also be present in the glomerular basement membrane.
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PMID:Isolation of glycosaminoglycans (heparan sulfate) from glomerular basement membranes. 15 57

Micro-scale isolation of sulfated glycopeptide from tissue was achieved by successive application of pronase digestion (Step 1), cetylpyridinium chloride-fractionation (Step 2), crude heparinase digestion or chondroitinase ABC digestion plus nitrous acid treatment (Step 3) and preparative cellulose acetate membrane-electrophoresis (Step 4). By this method, sulfated glycopeptide was obtained in a high yield from estrogen-treated rabbit uterus.
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PMID:A method for micro-scale isolation of sulfated glycopeptide from tissue. 52 51

The proteoglycans (PGs) in the guinea pig seminal vesicle were demonstrated ultrastructurally by both cuprolinic blue (CB) and ruthenium red (RR) staining. The PGs appeared as electron-dense granules with RR, but were filamentous following CB staining using the critical electrolyte concentration method. Three major types of PGs (T1, T2, T3) have been described according to their different locations and sizes. T1 filaments were short and were found mostly on both sides of the lamina densa of the basal lamina of the glandular epithelium (40-60 nm long) and also on the basal laminae of smooth muscle cells and capillary endothelial cells (20-30 nm long). In the epithelial basal lamina they were regularly spaced at an interval of 40-60 nm. T1 filaments in the lamina densa were smaller and more randomly distributed. Cytochemical characterisation of these PGs by various GAG degrading enzymes showed that T1 PGs are rich in heparan sulphate. T2 filaments were 30-40 nm long and closely associated with the collagen fibrils. They were arranged perpendicular to the long axis of collagen fibrils, also at intervals of about 60 nm. T2 filaments were removed by chondroitinase (Ch)-ABC, Ch-ABC plus Streptomyces (S)-hyaluronidase and pronase, but resistant to nitrous acid, heparitinase, heparinase, neuraminidase and S-hyaluronidase. These show that T2 filaments are rich in dermatan sulphate. T3 filaments (60-100 nm) were widely distributed in the stroma at sites such as the interstitial spaces of the lamina propria, the reticular layer below the basal lamina, around individual collagen fibrils or bundles of such fibres, and on the cell surfaces of fibroblasts. The T3 filaments were removed by Ch-ABC, Ch-AC and pronase but were resistant to heparitinase, heparinase, S-hyaluronidase, neuraminidase and nitrous acid. They are therefore rich in chondroitin sulphate.
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PMID:Cytochemical localisation and characterisation of proteoglycans (glycosaminoglycans) in the epithelial-stromal interface of the seminal vesicle of the guinea pig. 128 Jun 36

Adult human epidermis was cultured in whole skin organ culture under serum-free conditions in the presence of 35SO4. Proteoglycans (PG) comprised about 25% of the total (35SO4)-labeled material produced by epidermis. The rest of the incorporated activity displayed solubility characteristics typical of lipids. The molecular mass and the composition of the 35SO4-labeled epidermal PG and glycosaminoglycans (GAG) were studied using gel filtrations and agarose gel electrophoresis. The 35SO4-label of the epidermal PG was located in heparan sulfate (HS, approximately 75%) and chondroitin/dermatan sulfate (CS/DS, 25%), but not in keratan sulfate as determined by nitrous acid, chondroitinase AC II, chondroitinase ABC, and keratanase digestions, respectively. The molecular mass of the GAG chains was 10-40 kDa. The 35SO4-labeled PG were distributed between 60 and 600 kDa in agarose gel electrophoresis, with the highest activity at 350 kDa. Smaller activity peaks occurred at 150 and 60 kDa. Digestion of the PG with heparitinase removed most of the activity at 350 and 150 kDa, whereas chondroitinase ABC removed that at 60 kDa. A small amount of activity migrating between 600 and 1000 kDa was not affected by any of the GAG-degrading enzymes. Pulse chase experiments showed that the epidermal PG had an average half life of 24 h. The results thus demonstrate that human epidermis produces at least three different, rapidly metabolized PG. The PGs from 150 to 350 kDa contained heparan sulfate chains, whereas those at 60 kDa were chondroitin/dermatan sulfate PG.
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PMID:Proteoglycans synthesized by adult human epidermis in whole skin organ culture. 143 Dec 25

Binding of basic fibroblast growth factor (bFGF) to the extracellular matrix of cultured bovine aorta smooth muscle cells is likely to be mediated via heparan sulphate, since not only exogenous addition of heparan sulphate to the culture medium but also pretreatment of the cells with heparitinase (but not chondroitinase ABC) resulted in loss of binding. Comparison of the affinity of bFGF to various glycosaminoglycan-conjugated gels showed a direct and specific binding of bFGF to heparan sulphate. Heparan sulphate also bound to a bFGF affinity gel. However, the proportion of heparan sulphate bound varied depending on the source of the HS (more than 90% and 45% with pig aorta heparan sulphate and mouse EHS tumour heparan sulphate respectively). The bound heparan sulphate had the ability to protect bFGF from proteolytic digestion, but the unbound heparan sulphate did not. The results suggest the presence in the bound heparan sulphate of a specific structure involved in binding. Limited digestion with heparitinase I of porcine aorta heparan sulphate yielded 13% oligosaccharides bound to the gel, of which the smallest were octasaccharides. Analysis of a hexadecasaccharide fraction which was obtained at the highest yield among the bound oligosaccharides was performed by h.p.l.c. of the deamination products obtained with nitrous acid and the unsaturated disaccharide products formed by heparitinase digestion. Comparison of the disaccharide unit compositions exhibited a marked difference in IdoA(2SO4)GlcNSO3 and IdoA(2SO4)GlcNSO3(6SO4) units between the bound and unbound hexadecasaccharides. The amounts measured were 3 mol and 1 mol per mol of the former and 0.4 mol and 0.6 mol per mol of the latter. It is likely that the binding of bFGF to heparan sulphate may require the domain structure of the heparan sulphate to be composed of clustering IdoA(2SO4)-GlcNSO3 units.
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PMID:Structure of a heparan sulphate oligosaccharide that binds to basic fibroblast growth factor. 149 18

The purpose of this study was to investigate the pattern of sulphated glycosaminoglycan synthesis during morphogenesis and cytodifferentiation in mouse tooth rudiments and to compare the results with those obtained in another study for salivary gland, a branched organ. Sulphated glycosaminoglycan was labelled by incubating molar rudiments from day 15 of gestation to day 1 post partum in medium containing [35S]-sodium sulphate. The rudiments were washed, homogenized and digested in pronase and then were sequentially digested by chondroitinase ABC and chemically degraded by nitrous acid oxidation. The fractions from each of these procedures were analysed by chromatography on Sephadex G-50 columns. The analysis revealed that, during morphogenesis, levels of chondroitin sulphate increased to a peak of 91% at day 18 and levels of heparan sulphate diminished to 8% during this period. As cytodifferentiation occurred, the level of chondroitin sulphate dropped to 64% and that of heparan sulphate increased to 35%. These results are similar to those reported for rat submaxillary gland, a branching organ. It appears that this pattern of sulphated glycosaminoglycan synthesis is not a unique feature of branching morphogenesis but may be one which marks the transition between morphogenesis and cytodifferentiation in non-branching rudiments as well.
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PMID:The correlation of temporal regulation of glycosaminoglycan synthesis with morphogenetic events in mouse tooth development. 151 35

cDNA encoding the core protein of rat syndecan was cloned from a neonatal rat aortic cDNA library by polymerase chain reaction amplification. Expression of syndecan mRNA in rat aortic vascular smooth muscle (VSM) cells was demonstrated by reverse transcriptase-linked polymerase chain reaction amplification of syndecan sequences using total RNA from rat aortic VSM cells as templates. Polyclonal antibodies against rat syndecan core protein were produced by immunizing rabbits with a recombinant fusion protein containing a fragment of the extracellular domain. The anti-syndecan antibodies immunoprecipitated a large 35SO4-labeled molecule synthesized by cultured rat aortic VSM cells. The immunoprecipitated molecule was identified as a hybrid proteoglycan, based on results of alkaline, nitrous acid, and chondroitinase ABC digestions. On immunoblots the antibodies recognized a proteoglycan of greater than 200 kDa, with a core protein size after deglycosylation of approximately 50 kDa. The anti-syndecan antibodies stained cultured rat aortic VSM cells as well as tissue sections of neonatal and adult rat aortas in the medial, smooth muscle layer. On Northern blots of RNA isolated from cultured VSM cells, a syndecan cDNA probe hybridized to a major RNA species of 2.6 kilobases. Quantitative Northern blot analysis of total RNA isolated from VSM cells harvested at different cell densities revealed a decrease in syndecan mRNA levels with increased cell density. These results demonstrate the regulated synthesis of syndecan by rat VSM cells.
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PMID:Regulated expression of syndecan in vascular smooth muscle cells and cloning of rat syndecan core protein cDNA. 163 9

Mast cells are widely distributed in perivascular connective tissues, especially in areas of active tumor growth and vascular reactivity. Incubation of metabolically [35S]O4 = -labeled subendothelial extracellular matrix (ECM) with lysates of bone marrow-derived mouse mast cells (BMMC) resulted in extensive degradation of heparan sulfate (HS) into fragments 5 to 6 times smaller than intact HS side chains. A much lower activity (seven- to eightfold) was expressed by intact BMMC incubated in contact with the ECM. These fragments were not produced in the presence of heparin, were sensitive to deamination with nitrous acid, and resistant to further degradation with papain or chondroitinase ABC. These results indicate that an endoglycosidase (heparanase) is involved in BMMC-mediated degradation of HS in the subendothelial ECM. Heparanase activity was not detected in medium conditioned by cultured BMMC, or in lysates of Ableson transformed BMMC and rat basophilic leukemic (RBL) cells. Both heparanase and beta-hexosaminidase, a mast cell granule enzyme, were released on degranulation of BMMC induced by the calcium ionophore A23187, or by exposure to IgE-Ag, suggesting that heparanase is localized in the cell granules. Under these conditions, less than 5% of the cellular content of lactate dehydrogenase were released. Degradation of the ECM-HS by the mast cell heparanase and the associated release of HS-bound endothelial cell growth factors that are stored in ECM (Vlodavsky et al, Proc Natl Acad Sci USA 84:2292, 1987; Bashkin et al, Biochemistry 28:1737, 1989) may play a role in the proposed mast cell-mediated stimulation of neovascularization.
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PMID:Degranulating mast cells secrete an endoglycosidase that degrades heparan sulfate in subendothelial extracellular matrix. 169 99


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