Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.36 (hyaluronidase)
 4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

35S- as well as 3H-labeled glycosaminoglycans (GAG) produced by cultivated epithelium and fibroblasts of the rabbit cornea were treated with testicular hyaluronidase, leech hyaluronidase and chondroitinase-ABC or -AC. The fractionation-patterns of enzyme-treated GAG were compared with blanks not exposed to enzymes. The epithelial GAG revealed to be generally more resistant to the enzymatic degradation than the GAG synthesized by the fibroblasts, but--depending on the enzyme--in the GAG of both cell types the same fractions were attacked. The decline of the radioactivity in the fractions of enzyme-treated GAG allows the conclusions that both cell types produce relatively small amount of keratan sulfate but mainly chondroitin sulfates with a different degree of sulfation. In addition GAG, not present in the normal cornea, are synthesized: hyaluronic acid chiefly by fibroblasts and probably dermatan sulfate. The possible role of the fibroblastic and epithelial GAG in corneal wound repair is discussed.
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PMID:Biosynthesis of glycosaminoglycans by mammalian corneal epithelium and fibroblasts in vitro. II. Approach to specify the GAG from the two cell types. 12 25

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

Distribution of acid phosphatase, beta-glucuronidase, and lysosomal hyaluronidase in the anterior segment of the rabbit eye was studied biochemically. Acid phosphatase activity was higher in the anterior uvea and cornea but lower in the sclera. Beta-Glucuronidase activity was higher in the anterior uvea but lower in the corneoscleral tissues. Lysosomal hyaluronidase activity was higher in the anterior uvea. The inner layer of the corneoscleral junction showed the highest specific activity of beta-glucuronidase and lysosomal hyaluronidase among the corneoscleral tissues. Lysosomal hyaluronidase activity was detected in all corneoscleral tissues.
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PMID:Distribution of acid phosphatase, beta-glucuronidase, and lysosomal hyaluronidase in the anterior segment of the rabbit eye. 70 Sep 53

The lysosomal glycosidase activity of the eye tissues (the sclera and cornea), the bone tissues and cartilage were studied. The intraperitoneal injection of tyrocalcitonine (TCT), deoxycorticosterone (DOCS), hydrocortisone (HC), and somatotropic hormone (STH) influenced both the activity of beta-galactosidase, beta-glucosidase, and hyaluronidase, the the functional state of thy lysosomal membranes of the connective tissues under investigation. GC and STH caused stabilization, whereas DOCS and large doses of TCT--a labilizing effect on the lysosomal membranes and tissues understudy. The absolute activity of the enzymes in the homogenates decreased after the HC and STH injection. DOCS produced an opposite effect.
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PMID:[Responses of different types of connective tissue to hormone administration]. 89 Jan 33

Studies have been made on the activity of glycosidases from eye tissues of developing chick embryos and adult hens. The enzymes of carbohydrates metabolism (hyaluronidase, beta-glycosidase and beta-galactosidase) from the sclera, cornea and ciliary body were examined. It was demonstrated that the distribution of glycosidases in different tissues of the eye is not identical. The activity of beta-glycosidase and beta-galactosidase in all the tissues of 14-day embryos is higher than in adult hens; sharp reduction of the activity was observed at the stage of eye opening. The activity of hyaluronidase in the sclera and cornea of chick embryos is maintained at a low level up to the stage of eye opening, being subjected to minor changes.
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PMID:[Age related changes in the glycosidases of chick embryo eye tissues]. 94 74

A 5 1/2 year old boy with I-cell disease (mucolipidosis II) had bilateral corneal haziness, early cortical cataracts and bilateral prominence of his eyes associated with shallow bony orbits. He died of pneumonia at age 5 1/2 years. Light and electron microscopic examination of the ocular and orbital tissues revealed an accumulation of acid mucopolysaccharide positive, hyaluronidase resistant material in fibroblasts and histiocytes which had partially replaced Bowman's membrane and the anterior stromal cells of the cornea. Similar material, as well as glycolipid-like substance, was found in the conjunctiva and in the retrobulbar soft tissues.
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PMID:Ocular involvement in I-cell disease (mucolipidosis II). Light and electron microscopic findings. 108 52

The author presents a so far unknown pathological process interrupting permanently the regeneration of the superficially damaged cornea, and its consequences and therapy of the condition as well. The process occurs only in 5.6% of the injured individuals. The occurrence is in no correlation with the quality or extent of the damage. Also it is independent of the form and duration of therapy. The essence of the pathological changes is the slowing of corneal epithelisation within 2-4 days, followed by a complete cessation. After that a thin membrane-like layer develops simultaneously and evenly within 12 days on the area without epithelium, the surface of which is dull, transparent and whitish in colour. Within weeks or months an individually varying thickening of the membrane occurs, but the area does not grow. The surface becomes whitish-grey and is without any epithelium and with no adherence to tear. The deposits are closely and inseparably adherent to their base, their substance is rigid, being brittle only at the margins. The lesion is staining greenish-yellow with Na-fluorescein, and lively blue with toluidine blue. It is staining in small reddish-brown with rose bengal. In vivo the deposits are not measurably influenced by hyaluronidase, trypsin, alpha-chymotrypsin and papain. The microbes play no role in the process. Histological and electron-microscopical examinations suggest the corneal deposit are the product of the necrobiotic process occurring on the corneal surface during regeneration. The specific treatment consists of local application of corticoid-heparin. On the basis of the results of the examinations and literary data the author suggests that the corneal deposition and the similarly rare KCV (keratoconjunctivitis vernalis) plaque formation is the same specific process, i.e. the peculiar manifestation of the atopic state of the organism occurring independently of age.
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PMID:Ceasing of epithelisation and deposit formation of unknown origin on the cornea. 172 62

A 68-year-old man and a 66-year-old woman had diffuse corneal stromal deposits that stained with alcian blue and colloidal iron but did not react with periodic acid-Schiff stain and lipid stains. Similar deposits were found within postmortem sclera in one case, but not in other ocular or extraocular tissues. The abnormal material was sensitive to testicular hyaluronidase and chondroitinase. The material reacted with monoclonal antibody 9-A-2 after digestion by chondroitinase AC in one case and ABC in both cases, which is consistent with the identification of the glycosaminoglycans chondroitin 4-sulfate and dermatan sulfate. Electron microscopic examination of the cornea in both cases disclosed granular material in vacuoles dispersed extracellularly and, rarely, in keratocytes. Results of blood and skin fibroblast enzyme assays for clinically relevant mucopolysaccharidoses and mucolipidoses were normal in both patients, and there were no somatic abnormalities suggesting a storage disease.
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PMID:Unusual mucopolysaccharide disorder with corneal and scleral involvement. 211 Apr 15

This paper makes three points about how the chick corneal epithelium lays down the primary stroma, an orthogonally arranged array of well-spaced, 20-nm-diameter collagen fibrils. (1) Isolated corneal epithelia will, when cultured, lay down de novo stromas whose fibril-diameter distribution, fibril spacing, and proteoglycan profile are similar to those laid down in vivo. They differ from embryonic stromas in two ways: first, much of the chondroitin sulfate is released to the medium and, second, there is a relatively small amount of orthogonal organization. Epithelia seem only to lay down such stromas if they are separated from their original stromas with dispase, which leaves an intact basal lamina, and spread out, basal lamina downward, on a Nuclepore filter (poresize, 0.1 micron). (2) Chondroitin sulfate (CS), the predominant proteoglycan (greater than 85%), seems to play no significant role in collagen fibrillogenesis in vitro. Stromas laid down in its absence were indistinguishable from controls as assayed by fibril diameter, organization, and spacing and the amount of collagen synthesized. For these experiments, epithelia were cultured in the presence of hyaluronidase, which degrades CS, and p-nitrophenyl beta-D-xyloside, which inhibits the formation of links between the core protein and glycosaminoglycan side chains in the PG; the absence of intact CS was confirmed by gel filtration. We suggest that, in vivo, CS may facilitate the interfibrillar movement that takes place as the cornea grows. We have also found that keratinase, which degrades the very small amount of keratan sulfate present in the primary stroma, has no effect on stromal deposition. (3) There are substantial amounts of unidentified matrix components in primary stromas laid down both in vivo and in vitro. This conclusion was drawn from SEM observations on both types of stroma after they had been freeze-dried, a process which does not condense hydrated macromolecules. Even after being treated with hyaluronidase to remove the CS, substantial amounts of interfibrillar matrix were still present. Until these components are identified and their interactions with collagen are understood, the mechanisms responsible for stromal morphogenesis are unlikely to be understood.
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PMID:Does chondroitin sulfate have a role to play in the morphogenesis of the chick primary corneal stroma? 249 96

A 45-year-old man who had uneventful excision of bilateral pingueculae developed bilateral membranous lesions involving the bulbar conjunctivae and corneas. Histologically, the membranes were composed mainly of large fibrinous deposits intermixed with acute and chronic inflammatory cells with areas of fibroblastic and capillary proliferation resembling granulation tissue. By electronmicroscopy the amorphous acidophilic masses were composed of electron-dense, fibrillar material with a periodicity of 10-12 mm, which was consistent with fibrin. Despite mechanical removal of the membranes, they continued to recur rapidly over a period of several months. The lesions apparently responded slowly to topical enzymatic therapy that consisted of hyaluronidase (175 U/ml) and alpha-chymotrypsin (1:5000) drops. Follow-up examination, approximately 1 year after surgery, revealed that the patient was asymptomatic. Ocular examination disclosed slight persistence of gelatinous membranes on the bulbar conjunctivae, most prominent in the left eye.
Cornea 1989
PMID:Ligneous conjunctivitis after pingueculae removal in an adult. 292 87


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