Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04040 (Catalase)
 3,577 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Myocardial peroxisomes were investigated in normal and diabetic rats. Catalase and acyl-CoA oxidase activities were increased in the diabetic rat heart and immunoblot analysis showed that both enzyme proteins were markedly enhanced in diabetic heart homogenates. After immunoenzyme staining, catalase and acyl-CoA oxidase were localized in fine granules in the myocardium, which were increased in number in diabetic rats. The numerical density of the granules stained for catalase was increased 1.7 times and that for acyl-CoA oxidase 1.8 times, compared with controls. Protein A-gold labeling for catalase and acyl-CoA oxidase was present in myocardial peroxisomes. The labeling density for both enzymes was increased in diabetic rats by 1.6 times for catalase and 1.5 times for acyl-CoA oxidase, compared with controls. The results indicate that myocardial peroxisomes are increased in the diabetic rat and that this proliferation is accompanied by an increase in catalase and acyl-CoA oxidase activities.
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PMID:Proliferation of myocardial peroxisomes in experimental rat diabetes: a biochemical and immunocytochemical study. 136 21

The nature of the compartmentalization of catalase in human myeloid cells is an unresolved issue. Using a rabbit polyclonal antibody specific for catalase, indirect immunocytofluorescence of immature leukemic promyelocytes (HL-60 cells) showed a pattern of small, sharp, punctate staining in the cytoplasm of all cells, while mature neutrophils showed a larger diffuse, flocculent pattern of cytoplasmic staining. Differential centrifugation of nitrogen cavitates of HL-60 cells indicated that the putative catalase-containing compartment was relatively fragile compared with the compartment(s) that contained myeloperoxidase (MPO), beta-hexosaminidase, beta-glucuronidase, and lysosomal alpha-mannosidase activities. Parallel studies using dimethylsulfoxide (DMSO)-induced HL-60 cells and mature neutrophils showed that, in the course of differentiation, there was an apparent shift in the localization of catalase from the granule fraction to the cytosolic fraction. Percoll-sucrose density gradient centrifugation of HL-60 cell cavitates showed a catalase-containing compartment with a mean peak density (1.05 g/mL) significantly lower than that of the major myeloperoxidase-containing compartment (1.08 g/mL); in mature neutrophils, catalase activity comigrated with lactate dehydrogenase (LDH) activity. Catalase in isolated fractions was protected from proteolysis in the absence, but not in the presence, of 0.1% Triton X-100. Digitonin titration experiments confirmed the compartmentalized nature of catalase in immature HL-60 cells and were consistent with a cytosolic localization in mature neutrophils. Ultrastructural localization of catalase by Protein A-gold immunocytochemistry demonstrated four to six catalase-containing compartments in all HL-60 cell profiles. In mature neutrophils, catalase was localized primarily in the cytoplasmic matrix, although in fewer than 2% of the cell profiles, one to two catalase-containing compartments were observed. The changes in catalase localization that occur during myeloid differentiation appear to be similar to the changes that occur during erythroid and megakaryocytic differentiation, and may have potential clinical significance in the classification of acute leukemia and in the development of drug resistance.
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PMID:Changes in the localization of catalase during differentiation of neutrophilic granulocytes. 816 45