Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002878 (hemolytic anemia)
 7,530 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The oxidized form of glutathione transport was studied in human erythrocytes in pyrimidine 5'-nucleotidase (P5N) deficiency, a disorder in which the amounts of CTP and UTP in the erythrocytes are elevated. The inhibition of ATP-requiring oxidized glutathione (GSSG) transport by CTP and UTP is believed to play a role in elevating the levels of the reduced form of glutathione (GSH) in the erythrocytes of patients with P5N deficiency. The current investigation was undertaken to determine if GSSG transport actually decreases in the erythrocytes of such patients. Erythrocytes from a 17-year-old patient and a 13-year-old patient with P5N deficiency hemolytic anemia and from ten normal subjects were used as materials for the experiment. Erythrocytes, which had been previously incubated with [3H]glycine, were incubated at 37 degrees C, and the rate of [3H]GSSG transported by the cells was estimated. The velocity of GSSG transport out of the erythrocytes was quite low in the patients, 3.17-3.65 nmol GSSG/ml erythrocytes/hr at 37 degrees C in one case, and 3.30 nmol GSSG/ml erythrocytes/hr in the other case, vs that in the normal controls (6.00 +/- 0.80 nmol GSSG/ml erythrocytes/hr; mean +/- SD). The activity of gamma-glutamylcysteine synthetase and glutathione synthetase did not decrease in the patients. Decreased transport activity of GSSG in addition to a normal synthesis rate for GSH may explain the increased concentration of erythrocyte GSH in P5N deficiency.
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PMID:Erythrocyte-oxidized glutathione transport in pyrimidine 5'-nucleotidase deficiency. 288 6

A previous study revealed that DQ-2511, a new gastroprokinetic drug, induced hemolytic anemia together with increased Heinz body formation, preceded by a marked decrease in erythrocyte reduced glutathione (GSH) content, after 2 weeks of dosing onward in dogs. In this study, the effect of DQ-2511 on erythrocytes in the early period of dosing, in comparison with that of beta-acetylphenylhydrazine (APHZ), was investigated to confirm the difference between this drug and APHZ in the mechanism of increased Heinz body formation. DQ-2511 and APHZ were administered orally to beagle dogs for 1 week at dose levels of 600 and 4 mg/ kg, respectively. Dogs receiving APHZ showed anemia after dosing for 7 days, together with an increase in methemoglobin and Heinz body formation after 3 days of dosing. In contrast, blood GSH, glutathione reductase, and gamma-glutamylcysteine synthetase were only slightly decreased after dosing for 7 days. In dogs treated with DQ-2511, erythrocyte GSH began to decrease after 1 day of treatment and was about 25% of the control value after 7 days; however, no changes were seen in blood glutathione reductase, GSH peroxidase, or gamma-glutamylcysteine synthetase level. Hepatic GSH was decreased slightly. In another experiment, SD rats were administered DQ-2511 and APHZ orally for 1 week at dose levels of 1600 and 15 mg/kg, respectively. Rats receiving DQ-2511 showed no anemia or any changes in erythrocyte GSH and Heinz body formation. In contrast, rats treated with APHZ showed a marked anemia and increases in Heinz body formation and erythrocyte GSH. These results demonstrate that DQ-2511 causes a marked decrease in GSH in dogs, resulting in Heinz body anemia, whereas APHZ induces Heinz body formation after a significant increase in methemoglobin, and suggest that impairment of the GSH redox cycle and synthetases of GSH are not involved in the decreased GSH after DQ-2511 treatment. This difference in effects on GSH content may indicate the existence of a species difference in the anemia induced by DQ-2511.
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PMID:A possible mechanism of heinz body hemolytic anemia induced by DQ-2511, a new gastroprokinetic drug, in dogs. 892 30

Gamma-glutamylcysteine synthetase catalyzes the first step in glutathione synthesis. The enzyme consists of 2 subunits, heavy and light, with the heavy subunit serving as the catalytic subunit. A patient with hemolytic anemia and low red blood cell glutathione levels was found to have a deficiency of gamma-glutamylcysteine synthetase activity. Examination of cDNA from the patient and her mother showed that she was homozygous and that her mother was heterozygous for a A-->T transversion at nt1109 producing a deduced amino acid change of His370Leu. The partial genomic structure of the catalytic subunit of gamma-glutamylcysteine synthetase (GLCLC) was determined, providing some intron/exon boundaries to make it possible to sequence an affected part of the coding region from genomic DNA. The 1109A-->T mutation was not present in the DNA of 38 normal subjects. In the course of these studies we found a diallelic polymorphism in nt +206 of an intron and another polymorphism that consisted of a duplication of a CAGC at cDNA nt1972-1975 in the 3' untranslated region. The 2 polymorphisms were found to be only in partial linkage disequilibrium.
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PMID:The molecular basis of a case of gamma-glutamylcysteine synthetase deficiency. 1051 93

Glutathione is a tripeptide composed of glutamate, cysteine and glycine. Glutathione is present in millimolar concentrations in most mammalian cells and it is involved in several fundamental biological functions, including free radical scavenging, detoxification of xenobiotics and carcinogens, redox reactions, biosynthesis of DNA, proteins and leukotrienes, as well as neurotransmission/neuromodulation. Glutathione is metabolised via the gamma-glutamyl cycle, which is catalyzed by six enzymes. In man, hereditary deficiencies have been found in five of the six enzymes. Glutathione synthetase deficiency is the most frequently recognized disorder and, in its severe form, it is associated with hemolytic anemia, metabolic acidosis, 5-oxoprolinuria, central nervous system (CNS) damage and recurrent bacterial infections. Gamma-glutamylcysteine synthetase deficiency is also associated with hemolytic anemia, and some patients with this disorder show defects of neuromuscular function and generalized aminoaciduria. Gamma-glutamyl transpeptidase deficiency has been found in patients with CNS involvement and glutathionuria. 5-Oxoprolinase deficiency is associated with 5-oxoprolinuria but without a clear association with other symptoms. Dipeptidase deficiency has been described in one patient. All disorders are very rare and inherited in an autosomal recessive manner. Most of the mutations are leaky so that many patients have residual enzyme activity. Diagnosis is made by measuring the concentration of different metabolites in the gamma-glutamyl cycle, enzyme activity and in glutathione synthetase and gamma-glutamylcysteine synthetase deficiency, also by mutation analysis. Prenatal diagnosis has been preformed in glutathione synthetase deficiency. The prognosis is difficult to predict, as few patients are known, but seems to vary significantly between different patients. The aims of the treatment of glutathione synthesis defects are to avoid hemolytic crises and to increase the defense against reactive oxygen species. No treatment has been recommended for gamma-glutamyl transpeptidase, 5-oxoprolinase and dipeptidase deficiency.
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PMID:Inborn errors in the metabolism of glutathione. 1739 29

A previously undescribed mutation of hereditary gamma-glutamylcysteine synthetase (GCS) deficiency was found in a 5 year old boy of Moroccan origin. He presented with chronic haemolytic anaemia, delayed psychomotor development and progressive motor sensitive neuropathy of lower extremities. The parents were third degree relatives. The activity of glycolytic enzymes were found to be normal in the propositus, his parents and a sister, but and a complete lack of GSH was found in the propositus. Accordingly, the measurement of de novo GSH synthetic enzymes was undertaken, and severe GCS deficiency was found in the propositus. Both parents and his sister presented GCS activity ranging from 69% to 90% of normal. GCS gene sequencing showed that the propositus was homozygous for a 1241C>T mutation in exon 11 and both parents and his sister were heterozygous. This mutation predicts a Pro414Leu amino acid substitution. Even though the homology between GCS and crystallographically solved, functionally related proteins is not very high, a three-dimensional model of GCS was derived using Modeller Software. GCS deficiency is a very rare autosomal recessive disorder reported so far in only 8 unrelated probands with severe haemolytic anaemia. In only 3 of these was the anaemia associated with severe neurological dysfunction. We report here the fourth case of GCS deficiency presenting neuropathy, giving further support to the eventual relationship between this enzymopathy and neurological damage.
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PMID:Chronic non-spherocytic hemolytic anemia associated with severe neurological disease due to gamma-glutamylcysteine synthetase deficiency in a patient of Moroccan origin. 1802 85

Glutathione (gamma-glutamylcysteinylglycine) has diverse functions including free radicals scavenging and modulating many critical cellular processes. Glutathione is synthesized by the consecutive action of the enzymes glutamate-cysteine ligase (GCL) and glutathione synthetase. GCL is composed of a catalytic subunit encoded by the GCLC gene and a regulatory subunit encoded by the GCLM gene. GCL deficiency due to homozygous mutations in GCLC has been reported in 6 individuals from 4 independent families. All presented with hemolytic anemia and 4 had additional neurological manifestations including cognitive impairment, neuropathy, ataxia, and myopathy. In this report, we present additional 6 children from 2 independent consanguineous families with GCL deficiency. All the children presented with neonatal hemolytic anemia. Beyond the neonatal period, they did not have jaundice or hemolysis, but continued to have mild anemia. They all had normal development and neurological examination. The affected children from the first family had the homozygous mutation c.1772G>A (p.S591N) and the second family had the homozygous mutation c.514T>A (p.S172T) in GCLC. GCL deficiency can have a mild non-neurological phenotype or a more severe phenotype with neurological manifestations. GCL deficiency can be an underdiagnosed cause of hemolytic anemia, thus awareness may aid in early diagnosis, appropriate genetic counseling, and management.
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PMID:Clinical and molecular characterization of 6 children with glutamate-cysteine ligase deficiency causing hemolytic anemia. 2857 79