Effects of (15S)-hydroperoxyeicosatetraenoic acid and (15S)-hydroxyeicosatetraenoic acid on the acute- lymphoblastic-leukaemia cell line Jurkat: activation of the Fas-mediated death pathway.
The antiproliferative effects of 15-LOX (15-lipoxygenase) metabolites of arachidonic acid {(15S)-HPETE [(15S)-hydroperoxyeicosatetraenoic acid] and (15S)-HETE [(15S)-hydroxyeicosatetraenoic acid]} and the mechanism(s) involved were studied in the human T-cell leukaemia cell line Jurkat. (15S)-HPETE, the hydroperoxy metabolite of 15-LOX, inhibited the growth of Jurkat cells 3 h after exposure and with an IC(50) value of 10 microM. The hydroxy metabolite of 15-LOX, (15S)-HETE, on the other hand, inhibited the growth of Jurkat cells after 6 h of exposure and with an IC(50) value of 40 microM. The cells exposed to 10 microM (15S)-HPETE for 3 h or to 40 microM (15S)-HETE for 6 h showed increased expression of Fas ligand and FADD (Fas-associated death domain), caspase 8 activation, Bid (BH3-interacting domain death agonist) cleavage, decrease in mitochondrial membrane potential, cytochrome c release, caspase 3 activation, PARP-1 [poly(ADP-ribose) polymerase-1] cleavage and DNA fragmentation, suggesting the involvement of both extrinsic and intrinsic death pathways. Further studies on ROS (reactive oxygen species) generation revealed the involvement of NADPH oxidase. In conclusion, the present study indicates that NADPH oxidase-induced ROS generation activates the Fas-mediated death pathway.
Kumar
Kotha Anil
KA
Department of Animal Sciences, School of Life Sciences, University of Hyderabad, Hyderabad 500046, India.
Arunasree
Kalle M
KM
Roy
Karnati R
KR
Reddy
Nishanth P
NP
Aparna
Ankireddy
A
Reddy
Gorla Venkateswara
GV
Reddanna
Pallu
P
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism; D001093:Arachidonate 15-Lipoxygenase / Q000378:metabolism; D020169:Caspases / Q000378:metabolism; D002453:Cell Cycle / Q000187:drug effects; D016923:Cell Death / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D045304:Cytochromes c / Q000378:metabolism; D053938:DNA Fragmentation / Q000187:drug effects; D004789:Enzyme Activation / Q000187:drug effects; D053222:Fas Ligand Protein / Q000378:metabolism*; D005434:Flow Cytometry; D006801:Humans; D019169:Jurkat Cells; D015289:Leukotrienes / Q000737:chemistry* / Q000494:pharmacology*; D008054:Lipid Peroxides / Q000737:chemistry* / Q000494:pharmacology*; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D019255:NADPH Oxidases / Q000378:metabolism; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000473:pathology*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*; D013237:Stereoisomerism; D019014:fas Receptor / Q000378:metabolism
D051017:Apoptosis Regulatory Proteins; D053222:Fas Ligand Protein; D015289:Leukotrienes; D008054:Lipid Peroxides; D017382:Reactive Oxygen Species; D019014:fas Receptor; C025086:15-hydroperoxy-5,8,11,13-eicosatetraenoic acid; D045304:Cytochromes c; D001093:Arachidonate 15-Lipoxygenase; D019255:NADPH Oxidases; D011065:Poly(ADP-ribose) Polymerases; D051057:Proto-Oncogene Proteins c-akt; D020169:Caspases