Possible participation of a JAK2 signaling pathway in recombinant rat interleukin-5-induced prolongation of rat eosinophil survival.
Recombinant rat interleukin (IL)-5-induced prolongation of rat eosinophil survival in culture was inhibited in a concentration-dependent manner by the protein synthesis inhibitor cycloheximide, the DNA-dependent RNA synthesis inhibitor actinomycin D, and the tyrosine kinase inhibitor herbimycin A when examined 96 h after incubation. The MEK-1 inhibitor PD98059 inhibited IL-5-induced phosphorylation of both p44 and p42 MAP kinases, but the IL-5-induced prolongation of eosinophil survival was not inhibited. In contrast, the JAK2 inhibitor AG490 inhibited the IL-5-induced prolongation of eosinophil survival. Treatment of eosinophils with IL-5 resulted in phosphorylation of STAT5 but not STAT1, and the IL-5-induced phosphorylation of STAT5 was inhibited by AG490. These findings suggest that the activation of JAK2 tyrosine kinase and protein synthesis are required for the prolongation of rat eosinophil survival induced by recombinant rat IL-5. STAT5 phosphorylation might also participate in the IL-5-induced survival of rat eosinophils.
Ishihara
K
K
Laboratory of Pathophysiological Bichemistry, Graduate School of Pharmaceutical Sciences, Tohoku University, Japan.
Satoh
I
I
Mue
S
S
Ohuchi
K
K
D000818:Animals; D017209:Apoptosis; D016227:Benzoquinones; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003513:Cycloheximide / Q000494:pharmacology; D004268:DNA-Binding Proteins / Q000378:metabolism; D003609:Dactinomycin / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004804:Eosinophils / Q000187:drug effects* / Q000502:physiology; D005419:Flavonoids / Q000494:pharmacology; D015848:Interleukin-5 / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000494:pharmacology*; D053614:Janus Kinase 2; D047029:Lactams, Macrocyclic; D008297:Male; D008894:Milk Proteins; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011518:Proto-Oncogene Proteins; D011809:Quinones / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000494:pharmacology; D017828:Rifabutin / Q000031:analogs & derivatives; D050799:STAT5 Transcription Factor; D015398:Signal Transduction; D015534:Trans-Activators / Q000378:metabolism
D016227:Benzoquinones; D004268:DNA-Binding Proteins; D004791:Enzyme Inhibitors; D005419:Flavonoids; D015848:Interleukin-5; D047029:Lactams, Macrocyclic; D008894:Milk Proteins; D011518:Proto-Oncogene Proteins; D011809:Quinones; D011994:Recombinant Proteins; D050799:STAT5 Transcription Factor; D015534:Trans-Activators; D003609:Dactinomycin; D017828:Rifabutin; C020754:herbimycin; D003513:Cycloheximide; D011505:Protein-Tyrosine Kinases; C507927:Jak2 protein, rat; D053614:Janus Kinase 2; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one