Antieosinophilic activity of orazipone.
Orazipone is a novel sulfhydryl-reactive compound that has been previously shown to reduce lung eosinophilia in guinea pigs and rats and to inhibit degranulation in mast cells and cytokine production in monocytes and T-cells. However, the effects of orazipone on granulocyte longevity are unknown. Orazipone and its derivative 3-(4-chloro-3-nitro-benzylidene)-pentane-2,4-dione (OR-2370) reversed interleukin-5-afforded survival of human eosinophils by inducing apoptosis. In contrast, orazipone did not affect granulocyte macrophage-colony-stimulating factor-induced survival of human neutrophils. The effect of orazipone on eosinophil apoptosis is different from that of glucocorticoids in that even high con-centrations of interleukin-5 were not able to overcome the effect of orazipone. Orazipone further enhanced spontaneous apoptosis as well as that induced by CD95 ligation without inducing primary necrosis. OR-2370-induced DNA fragmentation was shown to be dependent on caspases 3 and 6 and c-jun-N-terminal kinase, whereas extracellular regulated kinase, p38 mitogen-activated protein kinase, and phosphatidylinositol 3-kinase as well as caspases 4, 8, and 9 seem not to mediate its actions. Our results suggest that orazipone and its derivative OR-2370 possess strong antieosinophilic activity and thus may have anti-inflammatory efficacy in the treatment of asthma and/or allergic conditions.
Kankaanranta
Hannu
H
The Immunopharmacology Research Group, Medical School/B, FIN-33014 University of Tampere, Finland. blhaka@uta.fi
Ilmarinen
Pinja
P
Zhang
Xianzhi
X
Nissinen
Erkki
E
Moilanen
Eeva
E
D017209:Apoptosis / Q000187:drug effects*; D001597:Benzylidene Compounds / Q000494:pharmacology*; D020169:Caspases / Q000378:metabolism; D053938:DNA Fragmentation; D004804:Eosinophils / Q000187:drug effects* / Q000201:enzymology; D006801:Humans; D015848:Interleukin-5 / Q000494:pharmacology; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D007659:Ketones / Q000494:pharmacology*; D009504:Neutrophils / Q000187:drug effects; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D013438:Sulfhydryl Compounds / Q000494:pharmacology*
C511620:3-(4-chloro-3-nitrobenzylidene)pentane-2,4-dione; D001597:Benzylidene Compounds; D015848:Interleukin-5; D007659:Ketones; D013438:Sulfhydryl Compounds; C502617:orazipone; D019869:Phosphatidylinositol 3-Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D020169:Caspases