title: Antimycin A-induced cell death depends on AIF translocation through NO production and PARP activation and is not involved in ROS generation, cytochrome c release and caspase-3 activation in HL-60 cells.
abstract: A respiratory inhibitor, antimycin A (AA), induced an apoptotic-like cell death characterized by nuclear and DNA fragmentation in human leukemia HL-60 cells. This cell death was significantly restricted by a nitric oxide synthase (NOS) inhibitor, N(G)-monomethyl-L-arginine (L-NMMA), and a poly(ADP-ribose) polymerase (PARP) inhibitor, 5-aminoisoquinoline (AIQ). Indeed, NO production and PARP overactivation were detected in the cells treated with AA. On the one hand, L-NMMA partly eliminated NO production and on the other, AIQ and L-NMMA also restricted PARP activation. Excessive signals related to PARP overactivation induce the translocation of an apoptosis-inducing factor (AIF) from the mitochondria to the nuclei, resulting in DNA fragmentation. In AA-treated cells, the nuclear translocation of AIF occurred. This translocation was restricted by pretreatment with AIQ and L-NMMA. Although pretreatment with ascorbic acid eliminated the reactive oxygen species (ROS) generation induced by the blockade of complex III by AA, the pretreatment did not protect the cells from AA-induced cell death. Furthermore, cytochrome c release or caspase-3 activation was not observed in the cells treated with AA. These results suggest that AA-induced cell death does not depend on respiratory inhibition and the succeeding cascades, but on NO production, PARP overactivation and AIF translocation.
authors.affiliation: Department of Biology and Geosciences, Graduate School of Science, Osaka City University, Sumiyoshi-ku, Osaka, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Ogita
authors.forename: Akira
authors.initials: A
authors.lastname: Ogita
authors.forename: Yoshinosuke
authors.initials: Y
authors.lastname: Usuki
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Fujita
authors.forename: Toshio
authors.initials: T
authors.lastname: Tanaka
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000494:pharmacology*; D000968:Antimycin A / Q000494:pharmacology*; D051033:Apoptosis Inducing Factor / Q000378:metabolism*; D002154:Calpain / Q000378:metabolism; D053148:Caspase 3 / Q000378:metabolism*; D016923:Cell Death / Q000187:drug effects; D002467:Cell Nucleus / Q000187:drug effects / Q000648:ultrastructure; D045304:Cytochromes c / Q000378:metabolism*; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D053938:DNA Fragmentation / Q000187:drug effects; D004789:Enzyme Activation / Q000187:drug effects; D005456:Fluorescent Dyes; D018922:HL-60 Cells; D006801:Humans; D008564:Membrane Potentials / Q000187:drug effects; D009243:NAD / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism*; D021381:Protein Transport; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D000903:Antibiotics, Antineoplastic; D051033:Apoptosis Inducing Factor; D005456:Fluorescent Dyes; D017382:Reactive Oxygen Species; D009243:NAD; D009569:Nitric Oxide; D000968:Antimycin A; D045304:Cytochromes c; D011065:Poly(ADP-ribose) Polymerases; D002154:Calpain; D053148:Caspase 3