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

Lymphocytes, monocytes, neutrophilic granulocytes and platelets were each separated to greater than 95% purity from six normal subjects, three patients with Gaucher's disease, two heterozygotes for Gaucher's disease, and one patient with Fabry's disease. Activities of the following acid hydrolases were determined: "acid" (pH 4.0) beta-glucosidase, pH 5.0 beta-glucosidase, alpha-galactosidase, alpha-arabinosidase, alpha-mannosidase, alpha-glucosidase, beta-glucuronidase, beta-galactosidase, beta-hexosaminidase, and acid phosphatase. Enzymatic activity varied greatly with cell type and the enzyme being measured; the importance of assaying pure preparations especially for heterozygote detection is emphasized. Gaucher's disease patients' cells were found to be deficient in the pH 4.0 acid beta-glucosidase, variable in the pH 5.0 beta-glucosidase, and normal in all other acid hydrolases tested, including acid phosphatase, the activity of which is known to be elevated in plasma. Blood cells of a patient with Fabry's disease were deficient in alpha-galactosidase and normal in all other acid hydrolases tested.
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PMID:Acid hydrolases in leukocytes and platelets of normal subjects and in patients with Gaucher's and Fabry's disease. 0 20

The release of acid hydrolases from cultured skin fibroblasts into the cell culture medium was studied in several lysosomal storage disorders (GM1-gangliosidosis, Fabry's disease, Hurler's disease, mannosidosis, and mucolipidosis). The levels of different activities were proportional to time (up to 44 h after medium change) and cell density with the exception of beta-glucosidase, which was not released. Culture medium from the fibroblasts of mucolipidosis patients exhibited higher activity of acid hydrolases than medium from cells of patients with GM1-gangliosidosis, Fabry's disease, Hurler's disease, and mannosidosis. These cells, however, exhibited somewhat higher levels of enzyme activity in their culture medium than control fibroblasts. The total production of acid hydrolases was yet rather similar in fibroblasts from controls and patients. Differential centrifugation showed that the highest specific activity of acid hydrolases was seen, as expected, in the lysosomal fraction, except in fibroblasts from patients with mucolipidosis, where the supernatant exhibited most activity. beta-Glucosidase, however, showed a normal differential centrifugation pattern also in fibroblasts from these patients.
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PMID:Lysosomal enzymes in medium from cultured skin fibroblasts from normal individuals and patients with lysosomal diseases. 40 77

We report a new assay for the detection of individuals heterozygous and homozygous for Gaucher's disease which requires relatively small samples of whole blood (0.3 ml), and which determines 4-methylumbelliferyl-beta-D-glucopyranoside:beta-glucosidase activity under conditions optimal for the determination of leukocyte glucocerebroside:beta-glucocereborsidase activity. The procedure involves the preparation of a leukocyte pellet from 50 mul of whole blood by hypotonic lysis of erythrocytes, followed by assay of beta-glucosidase activity at pH 5.5 in the presence of sodium taurocholate (0.6 g/100 ml). The methods described may also prove to be useful for the diagnosis of other diseases of enzyme deficiency which use fluorogenic substrates and leukocytes as a source of enzyme, such as Fabry's disease, Tay-Sachs disease, and generalized gangliosidosis.
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PMID:A microassay for Gaucher's disease. 80 4

Quantitative high-performance liquid chromatographic analysis of perbenzoylated sphingolipids has been used to study the correlations of body chemistry to clinical phenomena. Plasma sphingolipids were isolated from 32 Gaucher (beta-glucosidase deficiency) and six Fabry (alpha-galactosidase deficiency) patients by solvent partition and chromatographic separation on silicic acid columns. Plasma sphingolipids from a patient undergoing plasma-exchange were separated from interfering lipids with reversed-phase columns. Liquid-chromatographic analysis of sphingolipids provides useful supportive information for diagnoses because affected individuals are shown to possess increased circulating concentrations of the pathognomonic sphingolipid. We also used this technique to monitor sphingolipid concentrations in plasma and urine sediment during plasma exchange of a p atient with Fabry's disease. Regular plasma exchanges produced and maintained decreased concentrations of sphingolipids in plasma, but near pre-exchange concentrations were observed within days after the therapy was terminated.
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PMID:Application of "high-performance" liquid chromatography to the study of sphingolipidoses. 677 1

Calystegines, polyhydroxy nortropane alkaloids, are a recently discovered group of plant secondary metabolites believed to influence rhizosphere ecology as nutritional sources for soil microorganisms and as glycosidase inhibitors. Evidence is presented that calystegines mediate nutritional relationships under natural conditions and that their biological activities are closely correlated with their chemical structures and stereochemistry. Assays using synthetic (+)- and (-)-enantiomers of calystegine B2 established that catabolism by Rhizobium meliloti, glycosidase inhibition, and allelopathic activities were uniquely associated with the natural, (+)-enantiomer. Furthermore, the N-methyl derivative of calystegine B2 was not catabolized by R. meliloti, and it inhibited alpha-galactosidase, but not beta-glucosidase, whereas the parent alkaloid inhibits both enzymes. This N-methyl analog therefore could serve to construct a cellular or animal model for Fabry's disease, which is caused by a lack of alpha-galactosidase activity.
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PMID:Biological activities of the nortropane alkaloid, calystegine B2, and analogs: structure-function relationships. 898 98

An examination of the roots of Lycium chinense (Solanaceae) has resulted in the discovery of 14 calystegines, a cycloheptane bearing an amino group and three hydroxyl groups, and two polyhydroxylated piperidine alkaloids. Calystegines A7 and B5, in addition to the previously known calystegines A3, A5, A6, B1, B2, B3, B4, C1, C2 and N1, were isolated and determined as 1alpha,2beta,4alpha-trihydroxy-nortropane and 1alpha,2alpha,4alpha,7alpha-tetrahydroxy-nort ropane, respectively. L. chinense also had two polyhydroxytropanes bearing a methyl group on the nitrogen atom, unlike the previously reported nortropane alkaloids. They were established as N-methylcalystegines B2 and C1, and their N-methyl groups were found to be axially oriented from NOE experiments. 1Beta-amino-3beta,4beta,5alpha-trihydroxycyclohepta ne was also present in L. chinense and may be a biosynthetic precursor of the calystegines that occur in this plant. Two polyhydroxypiperidine alkaloids, fagomine and 6-deoxyfagomine, were isolated. Calystegine B2 is a potent competitive inhibitor of almond beta-glucosidase (Ki = 1.9 microM) and coffee bean alpha-galactosidase (Ki = 0.86 microM), while N-methylcalystegine B2 was a more potent competitive inhibitor of the latter enzyme (Ki = 0.47 microM) than the parent compound but showed a marked lack of inhibitory activities towards most other glycosidases. Since this compound is a very specific inhibitor of alpha-galactosidase and inhibits rat liver lysosomal alpha-galactosidase with a Ki of 1.8 microM, it may provide a useful experimental model for the lysosomal storage disorder, Fabry's disease. The addition of a hydroxyl group at C6exo, as in calystegines B1 and C1, enhances the inhibitory potential towards beta-glucosidase and beta-galactosidase but markedly lowers or abolishes inhibition towards alpha-galactosidase. Hence, the N-methylation of calystegine C1 did not enhance its inhibition of alpha-galactosidase. The chemical N-methylation of calystegines A3 and B4 markedly enhanced inhibition of coffee bean alpha-galactosidase, with Ki values of 5.2 microM and 36 microM, respectively, but almost eliminated their inhibitory potential towards beta-glucosidase and trehalase, respectively. Thus, methylation of the nitrogen atom significantly altered the specificity of the inhibitors.
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PMID:Specific alpha-galactosidase inhibitors, N-methylcalystegines--structure/activity relationships of calystegines from Lycium chinense. 934 81

Human lysosomal enzymes acid-beta-glucosidase (GCase) and acid-alpha-galactosidase (alpha-Gal A) hydrolyze the sphingolipids glucosyl- and globotriaosylceramide, respectively, and mutations in these enzymes lead to the lipid metabolism disorders Gaucher and Fabry disease, respectively. We have investigated the structure and stability of GCase and alpha-Gal A in a neutral-pH environment reflective of the endoplasmic reticulum and an acidic-pH environment reflective of the lysosome. These details are important for the development of pharmacological chaperone therapy for Gaucher and Fabry disease, in which small molecules bind mutant enzymes in the ER to enable the mutant enzyme to meet quality control requirements for lysosomal trafficking. We report crystal structures of apo GCase at pH 4.5, at pH 5.5, and in complex with the pharmacological chaperone isofagomine (IFG) at pH 7.5. We also present thermostability analysis of GCase at pH 7.4 and 5.2 using differential scanning calorimetry. We compare our results with analogous experiments using alpha-Gal A and the chaperone 1-deoxygalactonijirimycin (DGJ), including the first structure of alpha-Gal A with DGJ. Both GCase and alpha-Gal A are more stable at lysosomal pH with and without their respective iminosugars bound, and notably, the stability of the GCase-IFG complex is pH sensitive. We show that the conformations of the active site loops in GCase are sensitive to ligand binding but not pH, whereas analogous galactose- or DGJ-dependent conformational changes in alpha-Gal A are not seen. Thermodynamic parameters obtained from alpha-Gal A unfolding indicate two-state, van't Hoff unfolding in the absence of the iminosugar at neutral and lysosomal pH, and non-two-state unfolding in the presence of DGJ. Taken together, these results provide insight into how GCase and alpha-Gal A are thermodynamically stabilized by iminosugars and suggest strategies for the development of new pharmacological chaperones for lysosomal storage disorders.
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PMID:Effects of pH and iminosugar pharmacological chaperones on lysosomal glycosidase structure and stability. 1937 50