Role for TAK1 in cigarette smoke-induced proinflammatory signaling and IL-8 release by human airway smooth muscle cells

2012 ◽  
Vol 303 (3) ◽  
pp. L272-L278 ◽  
Author(s):  
Tonio Pera ◽  
Claudia Atmaj ◽  
Marieke van der Vegt ◽  
Andrew J. Halayko ◽  
Johan Zaagsma ◽  
...  

Chronic obstructive pulmonary disease (COPD) is an inflammatory disease, characterized by a progressive decline in lung function. Airway smooth muscle (ASM) mass may be increased in COPD, contributing to airflow limitation and proinflammatory cytokine production. Cigarette smoke (CS), the major risk factor of COPD, causes ASM cell proliferation, as well as interleukin-8 (IL-8)-induced neutrophilia. In various cell types, transforming growth factor-β-activated kinase 1 (TAK1) plays a crucial role in MAP kinase and NF-κB activation, as well as IL-8 release induced by IL-1β, TNF-α, and lipopolysaccharide. The role of TAK1 in CS-induced IL-8 release is not known. The aim of this study was to investigate the role of TAK1 in CS-induced NF-κB and MAP kinase signaling and IL-8 release by human ASM cells. Stimulation of these cells with CS extract (CSE) increased IL-8 release and ERK-1/2 phosphorylation, as well as Iκ-Bα degradation and p65 NF-κB subunit phosphorylation. CSE-induced ERK-1/2 phosphorylation and Iκ-Bα degradation were both inhibited by pretreatment with the specific TAK1 inhibitor LL-Z-1640-2 (5Z-7-oxozeaenol; 100 nM). Similarly, expression of dominant-negative TAK1 inhibited CSE-induced ERK-1/2 phosphorylation. In addition, inhibitors of TAK1 and the NF-κB (SC-514; 50 μM) and ERK-1/2 (U-0126; 3 μM) signaling inhibited the CSE-induced IL-8 release by ASM cells. These data indicate that TAK1 plays a major role in CSE-induced ERK-1/2 and NF-κB signaling and in IL-8 release by human ASM cells. Furthermore, they identify TAK1 as a novel target for the inhibition of CS-induced inflammatory responses involved in the development and progression of COPD.

2011 ◽  
Vol 300 (2) ◽  
pp. L295-L304 ◽  
Author(s):  
Charalambos Michaeloudes ◽  
Maria B. Sukkar ◽  
Nadia M. Khorasani ◽  
Pankaj K. Bhavsar ◽  
Kian Fan Chung

Reactive oxygen species (ROS) are generated as a result of normal cellular metabolism, mainly through the mitochondria and peroxisomes, but their release is enhanced by the activation of oxidant enzymes such as NADPH oxidases or downregulation of endogenous antioxidant enzymes such as manganese-superoxide dismutase (MnSOD) and catalase. Transforming growth factor-β (TGF-β), found to be overexpressed in airway smooth muscle (ASM) from asthmatic and chronic obstructive pulmonary disease patients, may be a pivotal regulator of abnormal ASM cell (ASMC) function in these diseases. An important effect of TGF-β on ASMC inflammatory responses is the induction of IL-6 release. TGF-β also triggers intracellular ROS release in ASMCs by upregulation of NADPH oxidase 4 (Nox4). However, the effect of TGF-β on the expression of key antioxidant enzymes and subsequently on oxidant/antioxidant balance is unknown. Moreover, the role of redox-dependent pathways in the mediation of the proinflammatory effects of TGF-β in ASMCs is unclear. In this study, we show that TGF-β induced the expression of Nox4 while at the same time inhibiting the expression of MnSOD and catalase. This change in oxidant/antioxidant enzymes was accompanied by elevated ROS levels and IL-6 release. Further studies revealed a role for Smad3 and phosphatidyl-inositol kinase-mediated pathways in the induction of oxidant/antioxidant imbalance and IL-6 release. The changes in oxidant/antioxidant enzymes and IL-6 release were reversed by the antioxidants N-acetyl-cysteine (NAC) and ebselen through inhibition of Smad3 phosphorylation, indicating redox-dependent activation of Smad3 by TGF-β. Moreover, these findings suggest a potential role for NAC in preventing TGF-β-mediated pro-oxidant and proinflammatory responses in ASMCs. Knockdown of Nox4 using small interfering RNA partially prevented the inhibition of MnSOD but had no effect on catalase and IL-6 expression. These findings provide novel insights into redox regulation of ASM function by TGF-β.


2015 ◽  
Vol 308 (8) ◽  
pp. L766-L775 ◽  
Author(s):  
Wilfred J. Poppinga ◽  
Irene H. Heijink ◽  
Laura J. Holtzer ◽  
Philipp Skroblin ◽  
Enno Klussmann ◽  
...  

β2-Agonist inhibitors can relieve chronic obstructive pulmonary disease (COPD) symptoms by stimulating cyclic AMP (cAMP) signaling. A-kinase-anchoring proteins (AKAPs) compartmentalize cAMP signaling by establishing protein complexes. We previously reported that the β2-agonist fenoterol, direct activation of protein kinase A (PKA), and exchange factor directly activated by cAMP decrease cigarette smoke extract (CSE)-induced release of neutrophil attractant interleukin-8 (IL-8) from human airway smooth muscle (ASM) cells. In the present study, we tested the role of AKAPs in CSE-induced IL-8 release from ASM cells and assessed the effect of CSE on the expression levels of different AKAPs. We also studied mRNA and protein expression of AKAPs in lung tissue from patients with COPD. Our data show that CSE exposure of ASM cells decreases AKAP5 and AKAP12, both capable of interacting with β2-adrenoceptors. In lung tissue of patients with COPD, mRNA levels of AKAP5 and AKAP12 were decreased compared with lung tissue from controls. Using immunohistochemistry, we detected less AKAP5 protein in ASM of patients with COPD Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage II compared with control subjects. St-Ht31, which disrupts AKAP-PKA interactions, augmented CSE-induced IL-8 release from ASM cells and diminished its suppression by fenoterol, an effect mediated by disturbed ERK signaling. The modulatory role of AKAP-PKA interactions in the anti-inflammatory effects of fenoterol in ASM cells and the decrease in expression of AKAP5 and AKAP12 in response to cigarette smoke and in lungs of patients with COPD suggest that cigarette smoke-induced changes in AKAP5 and AKAP12 in patients with COPD may affect efficacy of pharmacotherapy.


2006 ◽  
Vol 291 (1) ◽  
pp. L66-L74 ◽  
Author(s):  
Razao Issa ◽  
Shaoping Xie ◽  
Kang-Yun Lee ◽  
Rex D. Stanbridge ◽  
Pankaj Bhavsar ◽  
...  

Airway smooth muscle cells (ASMC) are a source of inflammatory chemokines that may propagate airway inflammatory responses. We investigated the production of the CXC chemokine growth-related oncogene protein-α (GRO-α) from ASMC induced by cytokines and the role of MAPK and NF-κB pathways. ASMC were cultured from human airways, grown to confluence, and exposed to cytokines IL-1β and TNF-α after growth arrest. GRO-α release, measured by ELISA, was increased by >50-fold after IL-1β (0.1 ng/ml) or 5-fold after TNF-α (1 ng/ml) in a dose- and time-dependent manner. GRO-α release was not affected by the T helper type 2 cytokines IL-4, IL-10, and IL-13. IL-1β and TNF-α also induced GRO-α mRNA expression. Supernatants from IL-1β-stimulated ASMC were chemotactic for neutrophils; this effect was inhibited by anti-GRO-α blocking antibody. AS-602868, an inhibitor of IKK-2, and PD-98059, an inhibitor of ERK, inhibited GRO-α release and mRNA expression, whereas SP-600125, an inhibitor of JNK, reduced GRO-α release without effect on mRNA expression. SB-203580, an inhibitor of p38 MAPK, had no effect. AS-602868 but not PD-98059 or SP-600125 inhibited p65 DNA-binding induced by IL-1β and TNF-α. By chromatin immunoprecipitation assay, IL-1β and TNF-α enhanced p65 binding to the GRO-α promoter, which was inhibited by AS-602868. IL-1β- and TNF-α-stimulated expression of GRO-α from ASMC is regulated by independent pathways involving NF-κB activation and ERK and JNK pathways. GRO-α released from ASMC participates in neutrophil chemotaxis.


2011 ◽  
Vol 301 (5) ◽  
pp. L822-L828 ◽  
Author(s):  
Tonio Pera ◽  
Riham Sami ◽  
Johan Zaagsma ◽  
Herman Meurs

Increased airway smooth muscle (ASM) mass is a major feature of airway remodeling in asthma and chronic obstructive pulmonary disease. Growth factors induce a proliferative ASM phenotype, characterized by an increased proliferative state and a decreased contractile protein expression, reducing contractility of the muscle. Transforming growth factor-β-activated kinase 1 (TAK1), a mitogen-activated protein kinase kinase kinase, is a key enzyme in proinflammatory signaling in various cell types; however, its function in ASM is unknown. The aim of this study was to investigate the role of TAK1 in growth factor-induced phenotypic modulation of ASM. Using bovine tracheal smooth muscle (BTSM) strips and cells, as well as human tracheal smooth muscle cells, we investigated the role of TAK1 in growth factor-induced proliferation and hypocontractility. Platelet-derived growth factor- (PDGF; 10 ng/ml) and fetal bovine serum (5%)-induced increases in DNA synthesis and cell number in bovine and human cells were significantly inhibited by pretreatment with the specific TAK1 inhibitor LL-Z-1640-2 (5 Z-7-oxozeaenol; 100 nM). PDGF-induced DNA synthesis and extracellular signal-regulated kinase-1/2 phosphorylation in BTSM cells were strongly inhibited by both LL-Z-1640-2 pretreatment and transfection of dominant-negative TAK1. In addition, LL-Z-1640-2 inhibited PDGF-induced reduction of BTSM contractility and smooth muscle α-actin expression. The data indicate that TAK1 plays a major role in growth factor-induced phenotypic modulation of ASM.


2007 ◽  
Vol 292 (6) ◽  
pp. L1385-L1395 ◽  
Author(s):  
K. G. Tirumurugaan ◽  
J. A. Jude ◽  
B. N. Kang ◽  
R. A. Panettieri ◽  
T. F. Walseth ◽  
...  

In human airway smooth muscle (HASM) cells, the expression of CD38, which synthesizes the calcium-mobilizing molecule cyclic ADP-ribose, is augmented by TNF-α, a cytokine implicated in asthma. We determined the role of mitogen-activated protein kinase (MAPK) in the activation of NF-κB and AP-1 in the regulation of CD38 expression in HASM cells. In HASM cells exposed to TNF-α (40 ng/ml), the inhibitors of extracellular signal-regulated kinase (ERK), p38, or c-Jun NH2-terminal kinase (JNK) decreased CD38 expression and ADP-ribosyl cyclase activity. Transfection of HASM cells with a dominant negative MEK decreased while a wild-type ERK increased TNF-α-induced CD38 expression. Electrophoretic mobility shift assays (EMSAs) were performed using nuclear proteins and consensus sequences to detect the effect of the MAPKs on NF-κB and AP-1 activation. EMSAs confirmed the role of p38 and JNK in mediating NF-κB and AP-1 activation. Transfection of a dominant negative c-Jun decreased TNF-α-induced CD38 expression indicating involvement of AP-1. Stability of TNF-α-induced CD38 transcripts were determined in the presence of MAPK inhibitors after arresting the transcription with actinomycin D. Transcript stability decreased in the presence of ERK and p38 MAPK, but not the JNK, inhibitors. These results indicate that regulation of CD38 expression through p38 and JNK MAPKs involves NF-κB and AP-1 activation, and ERK and p38 MAPKs also regulate expression posttranscriptionally through message stability.


2013 ◽  
Vol 65 ◽  
pp. S104
Author(s):  
Manuel Alejandro Ramirez-Lee ◽  
Hector Rosas-Hernandez ◽  
Samuel Salazar-Garcia ◽  
Jose Manuel Gutiérrez-Hernández ◽  
Ricardo Espinosa- Tanguma ◽  
...  

1997 ◽  
Vol 272 (5) ◽  
pp. L865-L871 ◽  
Author(s):  
B. Tolloczko ◽  
Y. L. Jia ◽  
J. G. Martin

Agents increasing intracellular adenosine 3',5'-cyclic monophosphate (cAMP) cause relaxation of airway smooth muscle. However, the mechanisms of their action are not fully understood. We investigated the role of cAMP in the modulation of intracellular Ca2+ concentration ([Ca2+]i) transients evoked by serotonin (5-HT) in cultured rat tracheal smooth muscle (TSM) cells. Forskolin (10(-7) M) caused a significant elevation of intracellular cAMP and a 60% relaxation of tracheal rings contracted with 5-HT but did not affect [Ca2+]i in TSM cells. Forskolin (10(-5) M) completely relaxed tracheal rings and significantly decreased [Ca2+]i during the sustained phase of the 5-HT response. Forskolin-induced relaxation was attenuated by the cAMP-dependent protein kinase A (PKA) inhibitor Rp diastereomer of cAMP (Rp-cAMPS; 10(-4) M) and by the guanosine 3',5'-cyclic monophosphate (cGMP)-dependent protein kinase (PKG) inhibitor [Rp isomer of 8-(4-chlorophenylthio)-guanosine 3',5'-cyclic monophosphorothioate, 10(-4) M]. The effects of forskolin on [Ca2+]i were not altered by the PKA inhibitor but were abolished by the PKG inhibitor and thapsigargin. These results indicate that, in rat TSM, the relaxant effects of high concentrations of cAMP may be mediated, at least in part, by facilitating the sequestration of Ca2+ into intracellular stores by a mechanism involving PKG.


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