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
Query: UNIPROT:P06889 (
Mol
)
630,302
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Gaucher disease is a disorder of sphingolipid metabolism resulting from an inherited deficiency of the lysosomal hydrolase
glucocerebrosidase
. Affected individuals present with a spectrum of clinical symptoms ranging from hepatosplenomegaly, haematological abnormalities, and bone pain in type 1 disease, to severe neurodegeneration and premature death in types 2 and 3 disease. Although the basic biochemical defect is well characterized, there remains a poor understanding of the underlying pathophysiology of disease. In vitro studies suggest that macrophage glucocerebroside storage leads to tissue dysfunction through complex mechanisms involving altered intracellular calcium homeostasis and apoptosis. In order to study the pathogenic roles of these complex interactions, a viable animal model for Gaucher disease is needed. The complexity of this single gene disorder has been emphasized by the varied results of previous murine Gaucher models, ranging from perinatal lethality to phenotypically and biochemically asymptomatic animals. Recognizing the need to modulate the biochemical phenotype in mice to produce a relevant model, we have created a murine strain with key exons of the
glucocerebrosidase
gene flanked by loxP sites. We show that expression of Cre-recombinase in cells of hematopoietic and endothelial origin results in deficiency of
glucocerebrosidase
in the liver, spleen, bone marrow, and peripheral white cells. Glucocerebroside storage in this model leads to progressive splenomegaly with Gaucher cell infiltration and modest storage in the liver by 26 weeks of age. These results indicate the utility of this loxP GBA targeted murine strain for understanding the complex pathophysiology of Gaucher disease.
Mol
Genet Metab 2007 Feb
PMID:Generation of a conditional knockout of murine glucocerebrosidase: utility for the study of Gaucher disease. 1707 75
Gaucher disease, the most prevalent lysosomal storage disease, results from an inherited deficiency in the enzyme
glucocerebrosidase
. Three clinical forms of Gaucher disease have been described: Type 1 non-neuronopathic, Type 2 acute neuronopathic, and Type 3 subacute neuronopathic. Although Gaucher disease is panethnic, its presentation reveals some ethnic-specific characteristics. The Type 1 form is most common among Caucasian patients. In contrast, the majority of Chinese Gaucher disease patients have early age of onset, severe hematological and skeletal complications, and often neurological involvement, resulting in early childhood death. In this report, we review 29 cases of Gaucher disease from 23 unrelated patients and 6 patients from 3 non-consanguineous families. Among these patients, 13 were diagnosed as Type 1, 10 as Type 2, and 6 as Type 3. A novel mutation, del 205-209ACCTT, was identified in the heterozygous form with mutation R353W (c.1174C>T) by DNA sequence analysis in 2 Type 1 patients who are sibs. Mutation R353W was also found in the heterozygous form in 3 other Type 1 patients, with mutation L444P in 2 sibs and a second unknown Gaucher allele in the third patient. The Gaucher genotypes of the remaining Type 1 patients were F37V/L444P, G46E/L444P, R48W/R120W, N188S/L444P, Y205C/L444P, N370S/L444P, and L444P/unknown. It was noted that mutation N370S in the patient was linked to the pv1.1(-)(1) haplotype present in Jewish patients. Among the Type 2 patients, L444P was present in the heterozygous form with mutation F213I, L385P, or the complex allele (RecNci) in 5 patients. The second most common mutation, F213I, was found in the heterozygous form in 6 patients with mutations N382K, L383R, or L444P. The other mutations found in the Type 2 patients were P122L, V375L, Y363C, M416V, and 383-400del. The genotypes of the 6 Type 3 patients identified were D409H/D409H, D409H/G202R, G46E/N188S, N188S/unknown, and L444P/L444P. While D409H has been reported as being associated with cardiovascular/ocular involvements in Gaucher disease, there have been no such complications in these patients. As noted, the majority of the Gaucher mutations we identified in the Chinese patients were either rare or absent in other populations. With the exception of N370S and R353W found only in the Type 1 form, the majority of these mutations are severe ones that result in poor prognosis and often Types 2 and 3 Gaucher disease.
Blood Cells
Mol
Dis
PMID:Gaucher disease among Chinese patients: review on genotype/phenotype correlation from 29 patients and identification of novel and rare alleles. 1719 53
We have recently shown that phosphatidylcholine (PC) metabolism is altered in a macrophage model of Gaucher disease. We now demonstrate that treatment of macrophages with conduritol-B-epoxide (CBE), a
glucocerebrosidase
inhibitor, results in elevated activity of CTP:phosphocholine cytidylyltransferase (CCT), the rate-limiting enzyme in the pathway of PC biosynthesis. Furthermore, we provide evidence for a role for CCT in Gaucher macrophage growth by using macrophages derived from a genetically modified mouse which lacks a specific CCT isoform, CCTalpha, in macrophages. Upon CBE-treatment, macrophage size, analyzed by microscopy and by FACS, was significantly increased in macrophages from control mice, but did not increase, or increased to a much lower extent, in CCTalpha-/- macrophages. Together, these results suggest that the increase in PC biosynthesis is mediated via CCTalpha, and suggests a possible role for macrophage CCTalpha in Gaucher disease pathology.
Blood Cells
Mol
Dis
PMID:Changes in macrophage morphology in a Gaucher disease model are dependent on CTP:phosphocholine cytidylyltransferase alpha. 1748 53
Tandem mass spectrometry has been used for determinations of enzyme activities in biological samples. Activities in rehydrated dried blood spots of lysosomal enzymes
glucocerebrosidase
, acid sphingomyelinase, galactocerebroside beta-galactosidase, acid-alpha-galactosidase, acid alpha-glucosidase, and alpha-D-iduronidase are measured simultaneously by multiple-reaction monitoring of ion dissociations from cations produced by electrospray ionization of enzymatic products. Simple and inexpensive assay protocols are described that are readily adopted for handling multiple samples in 96-well microtiter plates, employing simple separation steps, and using less than or equal to 3 micromol of synthetic or commercially available substrates, and less than 25 nmol of internal standards per analysis. The assays have the potential of being used for large-scale screening of newborns for the detection of inborn errors of metabolism.
Methods
Mol
Biol 2007
PMID:Tandem mass spectrometry in the detection of inborn errors of metabolism for newborn screening. 1748 16
Gaucher disease (GD) is the most frequently encountered lysosomal storage disease, caused by autosomal recessive inborn defects in the
glucocerebrosidase
gene (GBA) at 1q21. The disease is most common in the Ashkenazi Jewish population. GD can present with a vast phenotypic heterogeneity, which can be predicted to some extent from the underlying mutation. In this report, we describe a Lebanese Arab family with multigenerational incidence of GD caused by a heterozygous genotype of a rare mutation, R48W, and a common one, L444P. Our patients' clinical course is described. We also review the English literature for patients with this rare mutation.
Mol
Genet Metab 2007 Aug
PMID:Gaucher disease: different clinical manifestations associated with a rare mutation (R48W) in a Lebanese family. 1757 91
Gaucher disease is an autosomal recessive lysosomal storage disorder due to deficiency of the lysosomal enzyme
glucocerebrosidase
. Three clinical phenotypes, type 1, nonneuronopathic; and types 2 and 3, acute and subacute neuronopathic are recognized. The incidence of Gaucher disease in the Thai population is unknown, but likely under-diagnosed. We performed molecular analysis in four patients, from three sibships, with type 3 Gaucher disease. Four mutant
glucocerebrosidase
(
GBA
) alleles were identified including two novel splice site mutations, IVS6-1G>C and IVS9-3C>G; both are predicted to result in truncated protein products, p.F255fsX256, and p.K464fsX487 and p.S463fsX480, respectively. One patient, homozygous for the L444P point mutation, had a "Norbottnian-like" phenotype, with more severe visceral involvement, kyphosis, barreled chest, and no neurological involvement other than supranuclear gaze palsy. These molecular studies of neuronopathic Gaucher disease will provide additional genotype-phenotype correlation particularly in non-Caucasian population.
Blood Cells
Mol
Dis
PMID:Molecular characterization of type 3 (neuronopathic) Gaucher disease in Thai patients. 1768 91
Gaucher disease (GD) is a lysosomal storage disorder resulting from an inborn reduced activity or deficiency of
glucocerebrosidase
due mainly to mutations in the
glucocerebrosidase
gene. We have recently shown that mutant
glucocerebrosidase
variants present variable degrees of endoplasmic reticulum (ER) retention and undergo ER associated degradation (ERAD) in the proteasomes. The degree of ERAD is one of the factors that determine GD severity. In order to define what factors affect the ERAD process of
glucocerebrosidase
in GD, we focused on two brothers with GD, carrying the same mutations but presenting extremely different clinical manifestations. One is mildly affected while the other developed severe GD with nervous system complications. Our results strongly indicated that both brothers presented variable degrees of ERAD, which was more extensive in the severely affected brother. Measurement of cholesterol demonstrated high intracellular levels in cells that derived from the severely affected brother. Growing the cells in cholesterol depleted medium led to lessening in the degree of ERAD in cells that derived from the severely affected brother and thus to improvement in stabilization, maturation, lysosomal localization and activity of the mutant
glucocerebrosidase
variants. The same effect was achieved by treating the cells with the HMG CoA reductase inhibitor mevastatin. None of the treatments had a significant effect on
glucocerebrosidase
properties in normal cells or in cells that derived from the mildly affected brother, indicating that intracellular cholesterol is one of the factors that affect the ERAD process of
glucocerebrosidase
and may influence the severity of GD.
Mol
Genet Metab 2008 Apr
PMID:Intracellular cholesterol modifies the ERAD of glucocerebrosidase in Gaucher disease patients. 1816 Mar 22
Genetic and chemically induced neuronopathic mouse models of Gaucher disease were developed to facilitate understanding of the reversibility and/or progression of CNS involvement. The lethality of the skin permeability barrier defect of the complete gene knock out [gba, (
glucocerebrosidase
) GCase] was avoided by conditional reactivation of a low activity allele (D409H) in keratinocytes (kn-9H). In kn-9H mice, progressive CNS disease and massive glucosylceramide storage in tissues led to death from CNS involvement by the age of 14 days. Conduritol B epoxide (CBE, a covalent inhibitor of GCase) treatment (for 8-12 days) of wild type, D409H, D409V or V394L homozygotes recapitulated the CNS phenotype of the kn-9H mice with seizures, tail arching, shaking, tremor, quadriparesis, extensive neuronal degeneration loss and apoptosis, and death by the age of 14 days. Minor CNS abnormalities occurred after daily CBE injections of 100 mg/kg/day for 6 doses, but neuronal degeneration was progressive and glucosylceramide storage persisted in D409V homozygotes in the 2 to 5 months after CBE cessation; wild type and D409H mice had persistent neurological damage without progression. The persistent CNS deterioration, histologic abnormalities, and glucosylceramide storage in the CBE-treated D409V mice revealed a threshold level of GCase activity necessary for the prevention of progression of CNS involvement.
Mol
Genet Metab 2008 Jun
PMID:Dependence of reversibility and progression of mouse neuronopathic Gaucher disease on acid beta-glucosidase residual activity levels. 1834 21
Gaucher disease is an autosomal recessive disorder. It is characterized by the accumulation of glucosylceramide in lysosomes of mononuclear phagocyte system, attributable to acid beta-glucosidase deficiency. The main consequences of this disease are hepatosplenomegaly, skeletal lesions and, sometimes, neurological manifestations. At sub-inhibitory concentrations, several competitive inhibitors act as chemical chaperones by inducing protein stabilization and increasing enzymatic activity. Here we tested two iminosugars (NB-DNJ and NN-DNJ) and four aminocyclitols with distinct degrees of lipophilicity as pharmacological chaperones for
glucocerebrosidase
(
GBA
). We report an increase in the activity of
GBA
using NN-DNJ, NB-DNJ and aminocyclitol 1 in stably transfected cell lines, and an increment with NN-DNJ and aminocyclitol 4 in patient fibroblasts. These results on specific mutations validate the use of chemical chaperones as a therapeutic approach for Gaucher disease. However, the development and analysis of new compounds is required in order to find more effective therapeutic agents that are active on a broader range of mutations.
Blood Cells
Mol
Dis
PMID:Promising results of the chaperone effect caused by imino sugars and aminocyclitol derivatives on mutant glucocerebrosidases causing Gaucher disease. 1916 50
Recently, inhibition of L-type Ca(2+) channels, using either Diltiazem or Verapamil, has been reported to partially restore mutant
glucocerebrosidase
activity in cells from patients with Gaucher disease homozygous for the N370S or L444P alleles, as well as cells from patients with two other lysosomal storage diseases. It was hypothesized that these drugs act on the endoplasmic reticulum, increasing its folding efficiency, inhibited due to altered calcium homeostasis. Several other laboratories have reported that cells carrying either the N370S or the F213I alleles are amenable to enzyme enhancement therapy with pharmacological chaperones, whereas cells homozygous for L444P respond poorly. We found that Verapamil treatment does not enhance mutant enzyme activity in any of the cell lines tested, while Diltiazem moderately increases activity in normal cells, and in N370S/N370S and F213I/L444P, but not in L444P/L444P Gaucher cells, or in either of two adult Tay-Sachs disease cell lines. Since the mode of action of pharmacological chaperones and Diltiazem are believed to be different, we examined the possibility that they could act in concert. Diltiazem co-administered with known chaperones failed to increase enzyme activities above that reached by chaperone-treatment alone in any of the patient cell lines. Thus, we re-examined the possibility that Diltiazem acts as a pharmacological chaperone. We found that, at the acidic pH of lysosomes, Diltiazem was not an inhibitor, nor did its presence increase the heat stability of
glucocerebrosidase
. However, at neutral pH, found in the endoplasmic reticulum, Diltiazem exhibited both of these properties. Thus Diltiazem exhibits the biochemical characteristics of a
glucocerebrosidase
pharmacological chaperone.
Mol
Genet Metab 2009 Apr
PMID:Diltiazem, a L-type Ca(2+) channel blocker, also acts as a pharmacological chaperone in Gaucher patient cells. 1916 57
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>