Peroxynitrite mediates cytokine-induced IL-8 gene expression and production by human leukocytes.
Recent studies indicate that nitric oxide (NO) or related compounds may regulate the production of interleukin (IL)-8, a potent proinflammatory chemokine. Here we report that peroxynitrite (ONOO(-)) formed by a reaction of NO with superoxide mediates IL-8 gene expression and IL-8 production in IL-1beta- and TNF-alpha-stimulated human leukocytes in whole blood. The NO synthase inhibitors aminoguanidine and N(G)-nitro-L-arginine methyl ester blocked nuclear accumulation of activator protein-1 (AP-1) and nuclear factor (NF)-kappaB in both polymorphonuclear (PMN) and mononuclear leukocytes and inhibited IL-8 mRNA expression and IL-8 release by approximately 90% in response to IL-1beta and TNF-alpha. Enhanced ONOO(-) formation was detected in granulocytes, monocytes, and lymphocytes after challenge with IL-1beta or TNF-alpha. The addition of ONOO(-) (0.2-80 microM) to whole blood increased nuclear accumulation of AP-1 and NF-kappaB in PMN and mononuclear leukocytes and augmented IL-8 mRNA expression and IL-8 production in a concentration-dependent fashion. Pyrrolidine dithiocarbamate, an inhibitor of NF-kappaB activation, attenuated approximately 70% of IL-8 release evoked by IL-1beta, TNF-alpha, or ONOO(-). These results indicate that ONOO(-) formation may underlie the action of cytokines towards IL-8 gene expression in human leukocytes.
Zouki
C
C
Research Center, Maisonneuve-Rosemont Hospital, Québec, H1T 2M4, Canada.
József
L
L
Ouellet
S
S
Paquette
Y
Y
Filep
J G
JG
D000975:Antioxidants / Q000494:pharmacology; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D015870:Gene Expression / Q000187:drug effects; D006146:Guanidines / Q000494:pharmacology; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000235:genetics; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009566:Nitrates / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D011759:Pyrrolidines; D012333:RNA, Messenger; D013859:Thiocarbamates / Q000494:pharmacology; D018808:Transcription Factor AP-1 / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D000975:Antioxidants; D006146:Guanidines; D007375:Interleukin-1; D016209:Interleukin-8; D016328:NF-kappa B; D009566:Nitrates; D011759:Pyrrolidines; D012333:RNA, Messenger; D013859:Thiocarbamates; D018808:Transcription Factor AP-1; D014409:Tumor Necrosis Factor-alpha; C020972:pyrrolidine dithiocarbamic acid; C039642:peroxynitric acid; D019001:Nitric Oxide Synthase; C004479:pimagedine; D019331:NG-Nitroarginine Methyl Ester