Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This review delineates the subcellular distribution, biochemical characteristics, and metabolic functions of 5'-nucleotidase (5'NT), summarizes the analytical biochemistry of 5'NT, and assesses the clinical significance of 5'NT determinations in body fluids, cells, and tissues. Salient aspects of the clinical biochemistry of 5'NT, discussed herein, are as follows: (A) Serum 5'NT activity is generally elevated in hepatobiliary diseases, especially with intrahepatic obstruction, but, unlike serum alkaline phosphatase, serum 5'NT activity is not increased in infancy, childhood, pregnancy, or osteoblastic disorders. (B) In cancer patients, elevated serum 5'NT activity does not always indicate hepatobiliary involvement; in some cases, 5'NT may be released into serum from the primary tumor or local metastases. (C) Genetic deficiency of erythrocyte pyrimidine 5'NT activity is a common cause of hereditary non-spherocytic hemolytic anemia. (D) Acquired deficiency of erythrocyte pyrimidine 5'NT activity occurs in patients with beta-thalassemia and lead poisoning. (E) 5'NT activity is low in circulating monocytes, increases markedly upon their differentiation to tissue macrophages, and subsequently diminishes during macrophage activation. (F) Lymphocyte ecto-5'NT activity, a plasma membrane marker of cell maturation, is generally low in immunodeficiency states, and undergoes characteristic changes in patients with certain lymphomas and leukemias.
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PMID:The clinical biochemistry of 5'-nucleotidase. 218 4

During the delivery of oxygen by erythrocytes, highly reactive oxygen species such as superoxide anion arise. The presence of reactive species damages the cell constituents. Glutathione (GSH) functions to repair cells when they are attacked by oxidative stress. GSH is synthesized in erythrocytes and glutathione disulfide (GSSG) is transported outside the cells to maintain a high GSH/GSSG ratio. The redox cycle of GSH by glutathione reductase and glutathione peroxidase is closely related to G6PD. Hereditary enzyme deficiency related to GSH metabolism, with hemolytic anemia has been reported. G6PD deficiency causes hemolytic anemia due to insufficiency of the redox cycle of GSH. Deficiency of GSH synthesizing enzymes or glutathione reductase also causes hemolysis. Pyrimidine 5'-nucleotidase deficiency causes hemolytic anemia even when there is a high concentration of GSH. Accumulation of nucleotides in red cells causes inhibition of G6PD activity.
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PMID:[Impaired glutathione metabolism in hemolytic anemia]. 219 89

The relationship between undernutrition-induced alterations in some myelin membrane-bound enzyme activities and phospholipid fatty acid composition of this membrane was ascertained in developing rat brains. Undernutrition was imposed in pregnant dams through gestation and lactation, (last 10 days of gestation, and through lactation) by feed restriction. Experimental groups of animals received 50% of the amount of diet consumed by controls. Pups born to these mother rats were killed at day 7, 14 or 21 of postnatal age. Myelin membrane was isolated from the major regions of the brain, and analysed for phospholipid fatty acid profiles, phosphoinositides and ganglioside species. While there were no diet-related differences in the activities of 5'-nucleotidase (EC 3.1.3.5), myelin phospholipids from cerebella and brain stems of experimental rats exhibited lowered proportions of the long-chain polyunsaturated fatty acids, C20:4 (n - 6) and C22:6 (n - 3) concomitant with elevated activities of ouabain-sensitive Na+/K+-ATPase (EC 3.6.1.4). Levels of diphosphoinositide, triphosphoinositide and trisialogangliosides also decreased in myelin from brains of experimental animals. These results suggest a relationship between myelin phospholipid fatty acid profiles as indicators of membrane unsaturation, and the possibility of allosteric modification of Na+/K+-ATPase activity.
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PMID:Activity of myelin membrane Na+/K+-ATPase and 5'-nucleotidase in relation to phospholipid acyl profiles, ganglioside composition and phosphoinositides in developing brains of undernourished rats. 254 71

An 11-year-old girl had marked haemolytic anaemia since the first year of life. Physical examination revealed scleral and cutaneous icterus and slight splenomegaly. Haemoglobin concentration was reduced to 9.5 g/dl, while platelet count and bilirubin concentration were increased (350,000/microliter and 2.2 mg/dl, respectively). The erythrocytes showed marked basophilic stippling, its extent typical of pyrimidine-5'-nucleotidase deficiency. The enzyme activity in the erythrocytes was 15% of normal. Deficiency of this enzyme, inherited as an autosomal recessive, is probably one of the most common erythrocyte enzyme deficiencies causing haemolytic anaemia. It brings about the intracellular accumulation of pyrimidine nucleotides which via secondary metabolic changes causes an accelerated destruction of erythrocytes. There is no known causative treatment: splenectomy is ineffective against the anaemia.
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PMID:[Pyrimidine 5'-nucleotidase deficiency as the congenital cause of nonspherocytic hemolytic anemia]. 837 97