scholarly journals Interleukin-3, -5, and Granulocyte Macrophage Colony-Stimulating Factor–Induced Adhesion Molecule Expression on Eosinophils by p38 Mitogen-Activated Protein Kinase and Nuclear Factor-κB

2003 ◽  
Vol 29 (1) ◽  
pp. 133-147 ◽  
Author(s):  
Chun K. Wong ◽  
Wai K. Ip ◽  
Christopher W. K. Lam
2001 ◽  
Vol 356 (2) ◽  
pp. 525-530 ◽  
Author(s):  
Pisate J. KAMTHONG ◽  
Ming-chi WU

We have recently reported that interleukin-1α (IL-1α) can induce human macrophage colony-stimulating factor (M-CSF) expression through nuclear factor κB (NF-κB) activation, and treatment of human pancreatic MIA PaCa-2 cancer cells with forskolin or cAMP attenuated the NF-κB activation as well as M-CSF expression. In this study, we have further investigated the mechanism of cAMP attenuation. MIA PaCa-2 cells were incubated with forskolin or dibutyryl-cAMP and then stimulated with IL-1 for 1h. Cell lysates were immunoprecipitated by anti-inhibitory κB (IκB) kinase-β (IKKβ) antibody and the immune complex assayed for kinase activity using recombinant inhibitor of NF-κB (IκBα) as substrate. The levels of IKKβ in the respective cellular proteins were measured by subsequent Western blot. The results show that the level of IKK protein remains constant in the presence of cAMP, forskolin and/or IL-1, whereas IKK activity was robustly stimulated by IL-1. Nonetheless, dibutyryl-cAMP or forskolin did not affect the IKK activation induced by IL-1. This experiment suggests that elevated cAMP has no effect on IKK activity. IκBα protein level decreased markedly in IL-1-treated cells compared with the untreated. By contrast, cells treated with cAMP or forskolin possessed discernibly higher IκBα levels. In addition, we observed that forskolin potentiated and prolonged the IL-1-induced IκBα mRNA levels, whereas it did not stabilize the IκBα mRNA message. Wholly, these studies indicate that elevated cAMP antagonizes IL-1-induced M-CSF transcription by up-regulating IκBα gene induction and its consequent attenuation of NF-κB activation.


Blood ◽  
1999 ◽  
Vol 93 (1) ◽  
pp. 341-349 ◽  
Author(s):  
Kenichi Suzuki ◽  
Masayuki Hino ◽  
Fumihiko Hato ◽  
Noriyuki Tatsumi ◽  
Seiichi Kitagawa

Abstract To clarify the differences of the signaling pathways used by granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor- (TNF), we investigated activation of mitogen-activated protein kinase (MAPK) subtype cascades in human neutrophils stimulated by these cytokines. G-CSF exclusively tyrosine-phosphorylated extracellular signal-regulated kinase (ERK). GM-CSF tyrosine-phosphorylated ERK strongly and p38 MAPK weakly, whereas TNF tyrosine-phosphorylated p38 MAPK strongly and ERK weakly. Consistent with these findings, MEK, an upstream kinase of ERK, was phosphorylated by G-CSF, GM-CSF, and TNF, whereas MKK3/MKK6, an upstream kinase of p38 MAPK, was phosphorylated by GM-CSF and TNF, but not by G-CSF. The potency of these cytokines to phosphorylate ERK and MEK was GM-CSF > G-CSF > TNF, whereas that to phosphorylate p38 MAPK and MKK3/MKK6 was TNF > GM-CSF. C-Jun amino-terminal kinase (JNK) was not tyrosine-phosphorylated by any cytokine despite the existence of JNK proteins in human neutrophils, whereas it was tyrosine-phosphorylated by TNF in undifferentiated and all-trans retinoic acid-differentiated HL-60 cells. Increased phosphorylation of ERK or p38 MAPK was detected within 1 to 5 minutes after stimulation with each cytokine and was dependent on the concentrations of cytokines used. MEK inhibitor (PD98059) reduced tyrosine phosphorylation of ERK, but not p38 MAPK, induced by G-CSF, GM-CSF, or TNF. GM-CSF– or TNF-induced superoxide (O2−) release was inhibited by p38 MAPK inhibitor (SB203580) in a dose-dependent manner, suggesting the possible involvement of p38 MAPK in GM-CSF– or TNF-induced O2− release. The results indicate that G-CSF, GM-CSF, and TNF activate the overlapping but distinct MAPK subtype cascades in human neutrophils and suggest that the differential activation of ERK and p38 MAPK cascades may explain the differences of the effects of these cytokines on human neutrophil functions.


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