Role of c-jun N-terminal kinase in the induced release of GM-CSF, RANTES and IL-8 from human airway smooth muscle cells.
1. Human airway smooth muscle cells (HASMC) contribute to airway inflammation in asthma by virtue of their capacity to produce several inflammatory mediators including IL-8, GM-CSF and RANTES. The intracellular signal pathway underlying the production of these cytokines in HASMC is not entirely elucidated. 2. We examined the role of the mitogen-activated protein kinase (MAPK) c-jun N-terminal kinase (JNK) in TNFalpha- and IL-1beta-induced GM-CSF, RANTES and IL-8 production in HASMC by using a novel specific inhibitor for JNK (SP600125). 3. Confluent HASMC were treated with TNFalpha or IL-1beta (10 ng ml(-1)) for 24 h in the presence or absence of SP600125 (1-100 micro M). JNK activity was determined by a kinase assay. Phosphorylation of JNK, p38 MAPK and ERK was examined by Western blotting. Culture supernatants were assayed for GM-CSF, RANTES and IL-8 content by ELISA. 4. Maximum TNFalpha- or IL-1beta-induced phosphorylation of JNK in HASMC occurred after 15 min and returned to baseline levels after 4 h. SP600125 inhibited TNFalpha- and IL-1beta-induced JNK activity in HASMC as shown by the reduced phosphorylation of its substrate c-jun. Furthermore, GM-CSF, RANTES and to a lesser extent IL-8 release from HASMC treated with TNFalpha and IL-1beta was inhibited dosedependently by SP600125. 5. JNK activation is involved in TNFalpha- and IL-1beta-induced GM-CSF, RANTES and IL-8 production from HASMC. JNK may therefore represent a critical pathway for cytokine production in HASMC.
Oltmanns
Ute
U
Thoracic Medicine, National Heart & Lung Institute, Imperial College, Dovehouse St, London SW3 6LY, UK.
Issa
Razao
R
Sukkar
Maria B
MB
John
Matthias
M
Chung
K Fan
KF
D002478:Cells, Cultured; D018946:Chemokine CCL5 / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism*; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D016209:Interleukin-8 / Q000378:metabolism*; D048031:JNK Mitogen-Activated Protein Kinases; D008168:Lung / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism*; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000502:physiology*; D032389:Myocytes, Smooth Muscle / Q000187:drug effects / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D018946:Chemokine CCL5; D004791:Enzyme Inhibitors; D007375:Interleukin-1; D016209:Interleukin-8; D014409:Tumor Necrosis Factor-alpha; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases