Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002986 (Fabry)
 5,646 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The possibility of lowering the level of ceramide-3 (galactosyl-alpha(1 leads to 4)-galactosyl-beta(1 leads to 4)-glucosyl-beta(1 leads to 1)-ceramide) in the plasma of patients with Fabry's disease was investigated. An immobilized alpha-galactosidase (alpha-D-galactoside galactohydrolase, EC 3.2.1.22) was prepared by coupling purified fig alpha-galactosidase to Sepharose 4B. The pH optimum for the hydrolysis of the artificial substrate p-nitro-phenyl-alpha-D-galactopyranoside was shifted by approx. 0.5--1.0 pH unit to higher pH values upon coupling of the enzyme to Sepharose 4B. The immobilized enzyme was more stable than the native enzyme to incubation at 60 degrees C. The immobilized enzyme was able to hydrolyse ceramide-3 either at pH 4.5 or at pH 7.4 in an artificial system in which sodium taurocholate was used to solubilize the substrate. In contrast, when the immobilized enzyme was incubated with normal plasma or plasma from a patient with Fabry's disease, in which elevated levels of ceramide-3 occur, no hydrolysis of the glycosphingo-lipid could be detected. The results suggest that lowering of level of ceramide-3 in plasma from patients with Fabry's disease by enzymic means is not feasible.
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PMID:Properties of immobilized fig alpha-galactosidase and effect on ceramide-3 content of plasma from patients with Fabry's disease. 3 16

Trihexosylceramide, isolated from human kidney and labelled in the terminal galactose position by oxidation with galactose oxidase and reduction with sodium boro[3H]hydride, was used to study some of the properties of human leucocyte alpha-galactosidase. The enzyme was inactive in the absence of detergent. Of all the detergents tested a crude sodium taurocholate preparation displayed the greatest activity. The optimal detergent concentration varied from 2 to 4 mg/ml depending on the protein concentration and indicating that the enzyme activity was dependent on the protein/detergent ratio. Because of its influence in regulating enzyme activity, it is essential that care must be taken to ensure that the protein/detergent ratio of all incubation mixtures is kept relatively constant whenever the diagnosis of Fabry's disease is attempted.
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PMID:Trihexosylceramide alpha-galactosidase of human leucocytes. 10 20

Four major sialo compounds, termed GP-M1, GP-D1, GP-D2, and GP-D3 have been isolated from the urine of a novel glycoprotein storage disorder patient with angiokeratoma corporis diffusum which was discovered by Kanzaki et al. (Kanzaki, T., Yokota, M., Mizuno, N., Matsumoto, Y., and Hirabayashi, Y. (1989) Lancet April 22, 875-877). Based on the results of fast atom bombardment mass spectrometry, methylation analysis, and proton nuclear magnetic resonance spectroscopy, their chemical structures were concluded to be: (formula; see text) The yields of GP-M1, GP-D1, GP-D2, and GP-D3 were approximately 15, 6, 50, and 5 mg/liter of urine, respectively. The most major compound GP-D2, was further purified into single molecular species, threonine and serine type, by reversed phase high performance liquid chromatography. NMR analysis of the two purified compounds with single molecular species showed that the chemical shifts of anomeric protons of GalNAc were significantly different between threonine- and serine-linked GalNAc. Neither mannose-containing glycopeptides nor glycosphingolipids were excreted in the patient urine. From these results, this disease is thought to be caused by the deficiency of a lysosomal enzyme(s) acting on O-linked glycan chains.
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PMID:Isolation and characterization of major urinary amino acid O-glycosides and a dipeptide O-glycoside from a new lysosomal storage disorder (Kanzaki disease). Excessive excretion of serine- and threonine-linked glycan in the patient urine. 210 50

The presence of an alpha-galactolipid was investigated with a peroxidase-labelled lectin from Griffonia simplicifolia (GSA-I) with specific binding for terminal alpha-D-galactose residues. Normal kidney tissue was obtained from patients undergoing nephrectomy for renal neoplasms. For light microscopy, tissue was snap-frozen; 4 microns-thick sections were briefly fixed in paraformaldehyde and incubated with GSA (0.025 mg ml-1). The peroxidase activity was developed with 3-amino-9-ethylcarbazole. Adjacent sections were stained at the same time after lipid extraction with 3:1 (v/v) chloroform/methanol. For electron microscopy, 0.2-0.5 mm-thick paraformaldehyde-fixed blocks, with or without lipid extraction, were stained with peroxidase-labelled GSA. The label was developed with diaminobenzidine and osmium tetroxide. Some structures, such as tubular epithelia, stained both in lipid-extracted and non-extracted tissues, suggesting that glycoproteins were most likely involved. In addition, tissue stained immediately after fixation showed GSA reactivity on endothelial cell surfaces of intertubular capillaries and larger vessels. In lipid-extracted tissues, however, tubular epithelium was still positive for GSA but endothelial cells failed to stain. These findings suggest that a glycolipid, bearing a terminal alpha-galactose residue, is present on the endothelial cells in human kidney and possibly on tubular epithelia. Our data may explain the preferential storage of alpha-galactolipid in endothelial cells of patients with Fabry's disease and other biological phenomena such as Escherichia coli adhesion.
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PMID:Presence of an alpha-galactolipid on the cell surfaces of endothelial cells of human kidney. 267 70

Human lymphoid cell lines established by Epstein-Barr viral transformation of peripheral B-lymphocytes from normal subjects and from Fabry patients, were investigated for their ability to biosynthesize neutral glycosphingolipids from [14C]galactose and [14C]glucose as precursors. Galactose was taken up in the presence of high concentrations of glucose and selectively utilised by the cells in the synthesis of galactosphingolipids. The pattern of neutral glycosphingolipids labelled from [14C]galactose was slightly modified with time of labelling in either lymphoid cell line: the first labelled glycosphingolipid was lactosylceramide (LacCer) in the normal line and globotetraosylceramide (GbOse4Cer) in the Fabry line. After labelling for 96 h, a steady state was reached and the percentage of every type of labelled glycosphingolipid was stable in each cell line; however, differences in the neutral sphingolipid composition appeared between the various cell lines. When using radiolabelled glucose as precursor, the major part of the radioactivity was incorporated into neutral lipids and phospholipids; neutral sphingolipids were much less labelled than when using galactose. Catabolism of endogeneous labelled glycosphingolipids (synthesized by the cells during the 'pulse') was studied after cultivating the cells without radiolabelled precursors ('chase'). In the cells from normal subjects, all the neutral glycosphingolipids were slowly degraded (half-life time around 15-25 days for LacCer and GbOse3Cer). In contrast, in a lymphoid line from a Fabry patient, no appreciable degradation of GbOse3Cer occurred during 30 days. This block in the catabolism of GbOse3Cer is in good agreement with the previously reported deficiency of alpha-galactosidase A activity in this Fabry lymphoid cell line [Salvayre, R. et al. (1981) Biochim. Biophys. Acta 659, 445-456] and demonstrates that alpha-galactosidase B does not hydrolyze GbOse3Cer in the living cell (in contrast to the situation in vitro).
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PMID:[Neutral glycosphingolipids of Fabry's disease lymphoblastoid lines established by Epstein-Barr virus transformation]. 298 12

A simple and sensitive fluorometric method has been described for the differential determination of the activity of lysosomal alpha-galactosidase A and alpha-galactosidase B. The procedure employs 4-methylumbelliferyl-alpha-D-galactopyranoside as substrate and N-acetylgalactosamine as an inhibitor of alpha-galactosidase B, but not of alpha-galactosidase A to differentiate the two activities. This method was shown to be applicable in the differentiation of the two enzyme activities in human tissues and in the diagnosis of the heterozygous and hemizygous genotypes for Fabry's disease in cultured skin fibroblasts.
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PMID:Differential assay for lysosomal alpha-galactosidases in human tissues and its application to Fabry's disease. 626 21

A method for staining of alpha-galactosidase with the synthetic substrate alpha-naphthyl-alpha-galactopyranoside after isoelectric focusing on gel slabs has been devised. Depending on the method used for cell extraction, at least seven isozymes could be detected in cell extracts of cultured fibroblasts from normal individuals. Thermal treatment revealed that both heat-stable and heat-labile isozymes occur in normal fibroblasts. The heat-labile isozymes were not detected in cells from Fabry hemizygotes and thus truly reflect products of the alpha-gal A locus. Three heat-stable isozymes observed in normal individuals were also found in Fabry heterozygotes and hemizygotes and are presumably determined by the alpha-gal B locus. The remaining isozymes were stained very weakly in the hemizygotes and were heat-stable. The relation of these isozymes to the A or B locus is uncertain. After treatment with neuraminidase the alpha-gal A isozymes could not be detected and one of the alpha-gal B isozymes appeared broader. The isozyme pattern observed in heterozygotes was almost identical to the normal one.
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PMID:alpha-Galactosidase isozymes in normal individuals, and in Fabry hemizygotes and heterozygotes. 677 88

A histochemical study was performed on light- and electron-microscopic level in a case of Fabry's disease. The patient underwent kidney transplantation for renal failure and died of heart failure 6 months later. Patient's tissues were studied at the light- and electron-microscopic levels with various embedding and staining techniques for lipids and carbohydrates. Two peroxidase-labeled lectins (from Ricinus communis and from Bandeiraea simplicifolia) known to have affinity for alpha- and beta-D-galactose, were strongly reactive with the storage material on frozen sections. The ultrahistochemical and extraction tests showed that the typical granules had a variable reactivity and morphologic characteristics in different cells, probably reflecting different composition. A small number of typical deposits were also observed in the transplanted kidney. This is the first reported case of recurrence of the storage disease in the allograft. Of interest was also the fact that the patient's blood inhibited normal alpha-galactosidase activity, suggesting a possible inhibitor-related mechanism in the pathogenesis of the recurrence.
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PMID:Light- and electron-microscopic histochemistry of Fabry's disease. 678 1

The effect of galactose on alpha-galactosidase missense mutants causing Fabry disease was investigated in the COS-1 cell expression system and lymphoblasts. Three mutant enzymes, A156V, L166V and Q279E, showed increases in activity and amount in COS-1 cells cultured with galactose. Another mutant without catalytic activity, C142Y, did not show any changes. In lymphoblasts cultured with galactose, the enzyme activity increased significantly in four classical Fabry patients with the respective mutations, A156V, L166V, G260A and G373S, and in three atypical Fabry patients with the respective mutations, Q279E, R301Q and M296I. Such an increase was not observed in the other four classical Fabry patients, with C142Y, E66Q/R112C, G328R and N320K, respectively. This suggests that many missense mutations in the alpha-galactosidase gene causing Fabry disease allow the expression of catalytically active mutant enzymes regardless of the clinical phenotype, which are rapidly degraded under physiological conditions and stabilized by galactose.
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PMID:Galactose stabilizes various missense mutants of alpha-galactosidase in Fabry disease. 757 33

The expression product of a mutant alpha-galactosidase gene, Q279E (279Gln-->Glu), found in an atypical variant (cardiac form) of Fabry disease, was purified and characterized. It had kinetic properties similar to those of normal alpha-galactosidase, but was markedly thermolabile at neutral pH. Galactose and melibiose at high concentrations stabilized the mutant enzyme in vitro. Its catalytic activity was 15% of that for the normal enzyme, when it was expressed in COS-1 cells at 37 degrees C. The activity increased at 30 degrees C or in the presence of galactose at 37 degrees C. An increase was also observed in lymphoblasts from a patient with this mutation in the presence of galactose or melibiose. We conclude that this mutant protein is posttranslationally inactivated under the neutral conditions in the cells. The possibility of a new therapeutic approach is suggested.
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PMID:Characterization of a mutant alpha-galactosidase gene product for the late-onset cardiac form of Fabry disease. 790 61


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