Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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

Six mouse hybrid cell lines were isolated which secrete antibodies to rabbit corneal proteoglycan. All six antibodies interacted with the same fraction of the proteoglycan, precipitating approximately 50% of proteoglycan labelled in the protein moiety. A radioimmunoassay using these antibodies measured concentrations as low as 1 g/ml unlabelled rabbit corneal proteoglycan. Human corneal proteoglycan, corneal keratan sulfate, and an oligosaccharide fraction from corneal digests all interacted with the antibodies at concentrations similar to whole rabbit proteoglycan. Proteoglycans from cultured rabbit stromal fibroblasts and from sclera were 20 to 50-fold less effective in competition for antibody. Endo-beta-galactosidase treatment of proteoglycan reduced antibody binding, but protease or chondroitinase treatments did not. Labelled proteoglycan separated by antibody affinity chromatography contained only keratan sulfate, whereas proteoglycan not bound to affinity columns contained only chondroitin sulfate. The antibodies appear to recognise a carbohydrate structure found only on corneal keratan sulfate proteoglycan. This structure can serve as a basis for separation. This structure can serve as a basis for separation of corneal proteoglycan types using antibody affinity chromatography.
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PMID:Monoclonal antibodies to rabbit corneal keratan sulfate proteoglycan. 622 89

We have studied the distribution of the lysosomal sphingolipid hydrolases beta-glucosaminidase, beta-galactosaminidase, beta-galactosidase, alpha- and beta-glucosidases, and alpha-mannosidase in the bovine and human ocular tissues, choroid, cornea, lens, retina, and sclera using synthetic substrates in the form of the 4-methylumbelliferyl derivatives of the corresponding glycosides. As compared to the bovine ocular tissues, the human ocular tissues possessed higher levels of all the enzyme activities examined with the exception of beta-galactosidase, and alpha-glucosidase than the other bovine ocular tissues. In contrast to the retina, which is primarily a neural tissue, human and bovine lens have minimal or trace levels of all the lysosomal hydrolases examined. Human and bovine retina, cornea, sclera, and choroid possess enzyme activities which are higher than the lens. This would indicate a slow turnover of glycosphingolipids in lens tissue as compared to the other ocular tissues.
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PMID:Distribution of lysosomal hydrolases in human and bovine ocular tissues. 734 Oct 62

The mouse keratocan gene (Ktcn) expression tracks the corneal morphogenesis during eye development and becomes restricted to keratocytes of the adult, implicating a cornea-specific gene regulation of the mouse Ktcn [J. Biol. Chem., 273 (1998) 22584-22588]. To examine the functionality of the mouse Ktcn promoter, we have cloned and sequenced a 3.2kb genomic DNA fragment 5' of the mouse Ktcn gene, which was used to prepare a reporter gene construct that contained the 3.2kb 5' flanking sequence, exon 1 and 0.4kb of intron 1 of Ktcn, and beta-geo hybrid reporter gene. The beta-galactosidase (betaGal) activity was assayed in tissues of two of five transgenic mouse lines obtained via microinjection. In adult transgenic mice, betaGal activity was detected only in cornea, not in other tissues (e.g. lens, retina, sclera, lung, heart, liver, diaphragm, kidney, and brain). During ocular development, the spatial-temporal expression patterns of the betaGal recapitulated that of endogenous Ktcn in transgenic mice. Using XGal staining, strong betaGal activity was first detected in periocular tissues of E13.5 embryos, and restricted to corneal keratocytes at E14.5 and thereafter. Interestingly, in addition to cornea, betaGal activity was transiently found in some non-ocular tissues, i.e. ears, snout, and limbs of embryos of E13.5 and E14.5 but was no longer detected in those tissues of E16.5 embryos. The transient expression of endogenous keratocan in non-ocular tissues during embryonic development was confirmed by in situ hybridization. Taken together, our results suggest that the 3.2kb Ktcn promoter contains sufficient cis-regulatory elements to drive heterologous minigene expression in cells expressing keratocan. The identification of keratocyte-specific expression of betaGal reporter gene in the adult transgenic mice is an important first step in characterizing the Ktcn promoter in order to use it to drive a foreign gene expression in corneal stroma.
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PMID:Identification of a 3.2 kb 5'-flanking region of the murine keratocan gene that directs beta-galactosidase expression in the adult corneal stroma of transgenic mice. 1085 82

Gene transfer provides an exciting new approach for the treatment of retinal and choroidal diseases. Two areas of concern are the potential for vector-related toxicity and uncertainties associated with prolonged transgene expression. One way to address these concerns for transfer of genes encoding secreted proteins is to transduce cells on the outside of the eye, provided the gene product can gain access to the eye and have the desired effect. In this study, we investigated the feasibility of this approach. Periocular injection of an adenoviral vector encoding beta-galactosidase (AdLacZ.10) resulted in LacZ-stained cells throughout the orbit and around the eye. Compared to periocular injection of 5 x 10(9) particles of control vector, periocular injection of 5 x 10(9) or 1 x 10(9) particles of an adenoviral vector expressing pigment epithelium-derived factor (PEDF) regulated by a CMV promoter (AdPEDF.11) resulted in significantly elevated intraocular levels of PEDF and suppression of choroidal neovascularization. Periocularly injected recombinant PEDF was also found to diffuse through the sclera into the eye. Although similar experiments are needed in an animal with a human-sized eye, these data suggest that periocular gene transfer deserves consideration for the treatment of choroidal diseases.
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PMID:Periocular injection of an adenoviral vector encoding pigment epithelium-derived factor inhibits choroidal neovascularization. 1269 92