title: Calyculin A modulates activation of the NADPH-oxidase in Me2SO-differentiated HL-60 cells.
abstract: Human promyelocytic leukemia cells (HL-60) have been used as a model system in which to study the effects of protein phosphatase inhibitors on NADPH-oxidase activation. Since O2- is generated by NADPH-oxidase, we examined the effect of calyculin A pretreatment on oxidase activation in response to various agonists. When Me2SO-differentiated HL-60 cells were treated with calyculin A prior to the addition of phorbol 12-myristate 13-acetate (PMA), O2- production was inhibited; however, calyculin A enhanced O2- production by N-formyl-methionyl-leucyl-phenylalanine (FMLP). The decreased O2- production seen with calyculin A pretreatment followed by PMA may be due to diminished translocation of the p47-phox and p67-phox, cytosolic components of the oxidase, and inhibition of arachidonic acid release. Interestingly calyculin A pretreatment followed by either agonist significantly enhanced mitogen-activated-protein kinase (MAPK) activity. The differential effects of pretreatment with calyculin A on subsequent oxidase stimulation elicited by FMLP or PMA provide further evidence for substantial heterogeneity in the activation of the respiratory burst.
authors.affiliation: Department of Biochemistry, Dong-A University College of Medicine, Pusan, Korea. jipark@seunghak.donga.ac.kr
authors.forename: J I
authors.initials: JI
authors.lastname: Park
authors.forename: D J
authors.initials: DJ
authors.lastname: Uhlinger
authors.forename: B S
authors.initials: BS
authors.lastname: Chung
authors.forename: I H
authors.initials: IH
authors.lastname: Kim
authors.forename: J Y
authors.initials: JY
authors.lastname: Kwak
mesh_terms: D016718:Arachidonic Acid / Q000378:metabolism; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism; D002454:Cell Differentiation; D004121:Dimethyl Sulfoxide / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D018922:HL-60 Cells; D006801:Humans; D008387:Marine Toxins; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D019255:NADPH Oxidases / Q000378:metabolism*; D009504:Neutrophils / Q000187:drug effects / Q000378:metabolism*; D010080:Oxazoles / Q000494:pharmacology*; D010100:Oxygen / Q000378:metabolism; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors; D010750:Phosphoproteins / Q000276:immunology; D015398:Signal Transduction; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors
chemical_list: D004791:Enzyme Inhibitors; D008387:Marine Toxins; D010080:Oxazoles; D010750:Phosphoproteins; C079789:neutrophil cytosol factor 67K; D016718:Arachidonic Acid; D009240:N-Formylmethionine Leucyl-Phenylalanine; C059041:calyculin A; D019255:NADPH Oxidases; C060505:neutrophil cytosolic factor 1; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D010749:Phosphoprotein Phosphatases; D013755:Tetradecanoylphorbol Acetate; D010100:Oxygen; D004121:Dimethyl Sulfoxide