Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.6.1 (sulfatase)
3,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Metachromatic leukodystrophy (MLD) is a lysosomal storage disease, caused by deficiency of arylsulfatase A (ASA), that manifests primarily in the white matter of the nervous system. Currently, no specific treatment exists that will reverse its fatal outcome. Replacement therapy has been hampered by the blood-brain barrier (BBB). To circumvent this problem we designed an ex vivo gene therapy strategy that includes the retrovirus-mediated ASA transduction of cells, such as activated lymphocytes, that are able to traverse the BBB or other membranes of the CNS. For this purpose, two recombinant retroviruses based on the pLXSN vector were produced, containing the wild-type ASA cDNA or a pseudodeficiency ASA cDNA, which encodes a smaller enzyme with normal activity. After transduction, ASA activity increased more than 100-fold in fibroblasts from an MLD patient. Furthermore, ASA-transduced MLD PBLs expressed 30 times higher ASA activity when compared with control PBLs. Moreover, cell culture experiments demonstrated that transduced fibroblasts could efficiently transfer ASA to deficient cells across a transwell barrier, whereas transduced MLD lymphocytes could transfer ASA to deficient fibroblasts only by direct cell-to-cell contact. Finally, ASA was taken up by normal oligodendrocytes and Schwann cells, the target myelinating glial cells for therapy in MLD. These data suggest possible short-term strategies for transfer of ASA into the CNS via transduced autologous cells while long-term strategies, related to autologous transduced bone marrow transplant, take effect in patients.
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PMID:Transduced fibroblasts and metachromatic leukodystrophy lymphocytes transfer arylsulfatase A to myelinating glia and deficient cells in vitro. 975 37

Metachromatic leukodystrophy (MLD) is a lysosomal storage disease resulting from the deficient activity of arylsulfatase A (ASA) and the accumulation of sulfatides. The disease is characterized by several subtypes, designated by age at onset: the late-infantile-, juvenile-, and adult-onset variants. Mutation analysis of genomic DNA from a proband with each variant was performed to identify and characterize their causative ASA mutations. Two sisters with the infantile-onset disease were homoallelic for the missense mutation D335V, a juvenile-onset proband was heteroallelic for two novel missense mutations, P148L and P191T, and an adult-onset patient was heteroallelic for the H397Y and P426L mutations. The novel mutations were not identified in 108 normal alleles indicating that these base substitutions were not common polymorphisms. To further characterize the mutant gene products, the mutant enzymes were partially purified from cultured fibroblasts and their molecular weights and charges were compared by immunoblotting following SDS-PAGE or isoelectric focusing (IEF). Normal fibroblast ASA had a single, broad band at 54 kDa. The enzyme from the late-infantile-onset patient had distinct bands of 36 and 78 kDa, but lacked the normal 54-kDa species. The juvenile- and adult-onset patients each had a faint band of 54 kDa and several other bands ranging from 29 to 64 kDa. IEF revealed several bands for the partially purified normal enzyme with a relatively narrow pH range around 4.0, whereas numerous bands with a wider range of isoelectric points were observed with the enzymes from the juvenile- and adult-onset fibroblasts. In contrast, the enzyme from the late-infantile-onset proband had four bands with more acidic isoelectric points, none corresponding to those of the normal enzyme. These results document changes in both size and charge of the mutant enzymes from patients with different mutations and MLD subtypes.
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PMID:Metachromatic leukodystrophy: subtype genotype/phenotype correlations and identification of novel missense mutations (P148L and P191T) causing the juvenile-onset disease. 1038 28

Mucopolysaccharidosis type III A (MPS III A, Sanfilippo syndrome) is a rare, autosomal recessive, lysosomal storage disease characterized by accumulation of heparan sulfate secondary to defective function of the lysosomal enzyme heparan N- sulfatase (sulfamidase). Here we describe a spontaneous mouse mutant that replicates many of the features found in MPS III A in children. Brain sections revealed neurons with distended lysosomes filled with membranous and floccular materials with some having a classical zebra body morphology. Storage materials were also present in lysosomes of cells of many other tissues, and these often stained positively with periodic-acid Schiff reagent. Affected mice usually died at 7-10 months of age exhibiting a distended bladder and hepatosplenomegaly. Heparan sulfate isolated from urine and brain had nonreducing end glucosamine- N -sulfate residues that were digested with recombinant human sulfamidase. Enzyme assays of liver and brain extracts revealed a dramatic reduction in sulfamidase activity. Other lysosomal hydrolases that degrade heparan sulfate or other glycans and glycosaminoglycans were either normal, or were somewhat increased in specific activity. The MPS III A mouse provides an excellent model for evaluating pathogenic mechanisms of disease and for testing treatment strategies, including enzyme or cell replacement and gene therapy.
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PMID:A mouse model for mucopolysaccharidosis type III A (Sanfilippo syndrome). 1056 64

Metachromatic leukodystrophy (MLD) is an autosomal recessive, inherited, lysosomal storage disease caused by a deficiency in arylsulfatase A (ASA). This disease is characterized by progressive demyelination leading to severe neurological symptoms. Allogenic bone marrow transplantation at an early stage of clinical course is only effective treatment currently available. Accordingly the corrective transfer of the ASA gene into hematopoietic stem cells is thought to be an important option for curative treatment for MLD. We have recently developed a selectable vector system based on ex vivo sorting of transduced cells (Migita et al. 1995). In this study, we applied this selectable system for development of MLD gene therapy. A bicistronic retroviral vector containing ASA cDNA and CD24 cDNA as a selectable marker gene was constructed. This vector was successfully transduced on fibroblasts from MLD patients, ASA activity was increased 7-fold compared to normal untransduced cells. PCR Southern analysis of hematopoietic colonies showed that transduction efficiency of CD34+ cells was 11-22%. However, after fluorescence-activated cell sorting using anti-CD24 antibody, 75-100% of colonies became vector positive. The sorting raised the ASA activity several fold compared to untransduced CD34+ progenitors. These results suggest that a bicistronic ASA vector containing a CD24 selectable marker could be a useful component of gene therapy for MLD.
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PMID:Transduction of fibroblasts and CD34+ progenitors using a selectable retroviral vector containing cDNAs encoding arylsulfatase A and CD24. 1069 58

Metachromatic leukodystrophy is a lysosomal storage disease caused by the deficiency of arylsulfatase A. Here we describe a hitherto unknown arylsulfatase A allele carrying a E312D missense mutation and characterize the effects of this and three previously described missense mutations, G86D, Y201C, and D255H, on arylsulfatase A. In transfection experiments no enzyme activity can be expressed from arylsulfatase A cDNAs coding for the D255H substituted enzyme, whereas Y201C and E312D mutations were associated with low amounts of residual enzyme activity. All amino acid substitutions lead to a decreased stability of the mutant enzyme, and metabolic labeling experiments indicated that except for the E312D substitution the mutations cause arrest of the mutant arylsulfatase A polypeptides in a prelysosomal compartment.
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PMID:Characterization of four arylsulfatase A missense mutations G86D, Y201C, D255H, and E312D causing metachromatic leukodystrophy. 1075 Oct 93

A deficiency of arylsulfatase A (ASA) causes the lysosomal storage disease metachromatic leukodystrophy (MLD) which is characterized primarily by demyelination of the central nervous system. ASA-deficient mice develop a disease which resembles MLD in many respects and thus serve as an appropriate animal model for this disease. To establish gene therapy protocols for ASA-deficient mice, we constructed two retroviral vectors based on the murine stem cell virus. Both vectors harbor the human ASA cDNA controlled by the retroviral promoter/enhancer element, but differ by the presence or absence of a neomycin resistance gene driven by an internal promoter. A comparative analysis of the one- versus the two-gene vector and an amphotropic versus an ecotropic producer cell line revealed that the amphotropic producer cell line for the one-gene vector transfers ASA overexpression to the target cells most efficiently. The human ASA encoded by this vector is correctly expressed in heterologous mouse cells and corrects the metabolic defect of transduced ASA-deficient murine cells. The constructed one-gene vector might thus be a potentially useful tool for the development of a gene-based therapy for ASA-deficient mice. Gene Therapy (2000) 7, 805-812.
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PMID:Retrovirally expressed human arylsulfatase A corrects the metabolic defect of arylsulfatase A-deficient mouse cells. 1082 8

Sanfilippo syndrome type III A (Mucopolysaccharidosis (MPS) III A) is a rare, autosomal recessive, lysosomal storage disease, characterized by the accumulation of heparan sulfate and the loss of function of lysosomal heparan N-sulfatase activity. The disease leads to devastating mental and physical consequences and a mouse model that can be used to explore gene therapy and enzyme or cell replacement therapies is needed. We have previously identified a mouse with low sulfamidase activity and symptoms and pathologies typical of MPS III A (Bhaumik, M., Muller, V. J., Rozaklis, T., Johnson, L., Dobrenis, K., Bhattacharyya, R., Wurzelmann, S., Finamore, P., Hopwood, J. J., Walkley, S. U., and Stanley, P. [1999] A mouse model for mucopolysaccharidosis type III A (Sanfilippo syndrome). Glycobiology 9, 1389--1396). We now show that the sulfamidase gene of the MPS III A mouse carries a novel mutation (G91A) that gives an amino acid change (D31N) likely to interfere with the coordination of a divalent metal ion in the active site of this sulfatase. This spontaneous mouse mutant is an excellent model for MPS III A in humans as this disease often arises due to a missense mutation in lysosomal sulfamidase.
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PMID:A novel missense mutation in lysosomal sulfamidase is the basis of MPS III A in a spontaneous mouse mutant. 1118 66

Mucopolysaccharidosis (MPS) Type VI (Maroteaux-Lamy Disease) is the lysosomal storage disease characterized by deficient arylsulfatase B activity and the resultant accumulation of dermatan sulfate-containing glycosaminoglycans (GAGs). A major feature of this and other MPS disorders is abnormal cartilage and bone development leading to short stature, dysostosis multiplex, and degenerative joint disease. To investigate the underlying cause(s) of degenerative joint disease in the MPS disorders, articular cartilage and cultured articular chondrocytes were examined from rats and cats with MPS VI. An age-progressive increase in the number of apoptotic chondrocytes was identified in the MPS animals by terminal transferase nick-end translation (TUNEL) staining and by immunohistochemical staining with anti-poly (ADP-ribose) polymerase (PARP) antibodies. Articular chondrocytes grown from these animals also released more nitric oxide (NO) and tumor necrosis factor alpha (TNF-alpha) into the culture media than did control chondrocytes. Notably, dermatan sulfate, the GAG that accumulates in MPS VI cells, induced NO release from normal chondrocytes, suggesting that GAG accumulation was responsible, in part, for the enhanced cell death in the MPS cells. Coculture of normal chondrocytes with MPS VI cells reduced the amount of NO release, presumably because of the release of arylsulfatase B by the normal cells and reuptake by the mutant cells. As a result of the enhanced chondrocyte death, marked proteoglycan and collagen depletion was observed in the MPS articular cartilage matrix. These results demonstrate that MPS VI articular chondrocytes undergo cell death at a higher rate than normal cells, because of either increased levels of dermatan sulfate and/or the presence of inflammatory cytokines in the MPS joints. In turn, this leads to abnormal cartilage matrix homeostasis in the MPS individuals, which further exacerbates the joint deformities characteristic of these disorders.
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PMID:Articular chondrocytes from animals with a dermatan sulfate storage disease undergo a high rate of apoptosis and release nitric oxide and inflammatory cytokines: a possible mechanism underlying degenerative joint disease in the mucopolysaccharidoses. 1155 79

Mucopolysaccharidosis type VI (MPS VI) is an autosomal recessive lysosomal storage disease caused by a deficiency of N-acetylgalactosamine-4-sulphatase (arylsulfatase B, ASB). We report the clinical investigation and mutation analysis of two Taiwanese patients with severe (Case 1) and intermediate (Case 2) phenotypes of MPS VI. Three missense mutations and one polymorphism were identified. Case 1 was found to have a novel heteroallelic C-to-G transversion at nucleotide 1197 causing a phenylalanine to leucine substitution at residue 399 (Phe399Leu), and a heteroallelic Gln239Arg mutation. In Case 2, a heterozygous Cys192Arg mutation and a Val358Met polymorphism were identified. Among these three mutations, the Gln239Arg and Phe399Leu substitutions have so far been observed only in the Taiwanese population. The correlation between genotype and phenotype contributes to molecular pre- and post-natal diagnosis for MPS VI patients.
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PMID:Mucopolysaccharidosis type VI: Report of two Taiwanese patients and identification of one novel mutation. 1180 22

Metachromatic leukodystrophy (OMIM 250100) is a lysosomal storage disease caused by the deficiency of arylsulfatase A (ARSA, EC 3.1.6.8). This disease affects mainly the nervous system, because patients cannot degrade 3-O-sulfo-galactosylceramide (sulfatide), a major myelin lipid. Here we describe the characterization of the biochemical effects of two arylsulfatase A missense mutations, P425T and C300F. Transfection experiments demonstrate the expression of residual ARSA enzyme activity for P425T, but not for C300F substituted ARSA. Relative specific activity determination showed that the P425T substituted enzyme has retained about 12% of specific enzyme activity, whereas the C300F substituted enzyme is reduced to less than 1%. Pulse-chase experiments reveal that both mutant proteins are unstable, with a half life of less than 6 hr. Increased secretion upon addition of NH(4)Cl indicates that the mutant proteins can pass the Golgi apparatus and thus are not degraded in the endoplasmic reticulum (ER), but in the lysosomes. This is supported by experiments, which demonstrate the presence of mannose-6-phosphate residues on the oligosaccharide side chains of the mutant proteins. Addition of the cysteine protease inhibitor leupeptin increases the amount of ARSA activity in cells expressing the P425T substituted enzyme, whereas no increase in activity was seen with C300F substituted ARSA.
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PMID:Biochemical characterization of two (C300F, P425T) arylsulfatase a missense mutations. 1250 99


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