Disease-specific expression and regulation of CCAAT/enhancer-binding proteins in asthma and chronic obstructive pulmonary disease

Pulmonary Cell Research, Department of Research and Pneumology, Department of Internal Medicine, University Hospital Basel, Basel, Switzerland.
Journal of Allergy and Clinical Immunology (Impact Factor: 11.25). 02/2007; 119(1):98-105. DOI: 10.1016/j.jaci.2006.07.056
Source: PubMed

ABSTRACT CCAAT/enhancer-binding proteins (C/EBPs) control cell proliferation; lack of C/EBPalpha correlates with increased proliferation of bronchial smooth muscle cells (BSMCs) of asthmatic patients.
We sought to assess disease-specific expression of C/EBPalpha, beta, delta, and epsilon and the effects of budesonide (10(-8) mol/L) and formoterol (10(-8) mol/L).
Expression and function of C/EBPalpha, beta, delta, and epsilon BSMCs of control subjects (n = 9), asthmatic patients (n = 12), and patients with chronic obstructive pulmonary disease (COPD; n = 10) were determined.
The control group expressed C/EBPalpha, beta, delta, and epsilon, which were upregulated by serum (5%). Budesonide completely inhibited C/EBPalpha and beta expression; formoterol increased C/EBPalpha expression (2-fold). C/EBPdelta and epsilon expression were not affected by the drugs. The asthmatic group did not appropriately express C/EBPalpha. Basal levels of C/EBPbeta, delta, and epsilon were upregulated by serum (5%). Budesonide and formoterol increased C/EBPbeta levels (3.4-fold and 2.5-fold, respectively), leaving C/EBPalpha, delta, and epsilon levels unaffected. The COPD group normally expressed C/EBPalpha, beta, and epsilon, which were upregulated by serum treatment (5%). Basal levels of C/EBPdelta were downregulated by serum in 7 of 10 BSMC lines. Budesonide inhibited C/EBPalpha and beta expression, upregulated C/EBPdelta (3.2-fold), and had no effect on C/EBPepsilon. Formoterol upregulated C/EBPalpha expression (3-fold) but not the other C/EBPs. Protein analysis and electrophoretic mobility shift assay confirmed the disease-specific expression pattern of C/EBPalpha in asthmatic patients and C/EBPdelta in patients with COPD.
The expression and regulation of C/EBPs in BSMCs of asthmatic patients and patients with COPD seems disease specific. Budesonide and formoterol modulate C/EBP expression in a drug- and disease-specific pattern.
The data could provide a method to discriminate between asthma and COPD at an early disease stage.

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    • "Cellular proteins were isolated from confluent cells by dissociation in lysis buffer, (62.5 mM TriseHCL, pH 6.8; 2% sodium dodecylsulfate, 2% b-mercapto-ethanol, 10% glycerol) and analyzed by immuno-blotting for the expression of cAMP response element binding protein (CREB), phosphorylated CREB (P-CREB) and atubulin (all: Cell Signaling Technology) as described earlier for other proteins [20] "
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    ABSTRACT: Mesenchymal cells (fibroblasts) of the airway wall respond to cholinergic stimulation by releasing pro-inflammatory and chemotactic cytokines and may thus contribute to chronic inflammation of the lung. Here, we studied the anti-inflammatory potential of olodaterol, a long acting β2-adrenergic receptor agonist, and tiotropium, a long-acting muscarinic receptor antagonist, and whether they interact at the level of the cyclic AMP dependent signaling pathway. Pulmonary fibroblasts of asthmatic (n=9) and non-asthmatic (n=8) subjects were stimulated with the muscarinic receptor agonist carbachol and interleukin-1β (IL-1 beta) in presence or absence of tiotropium or olodaterol alone, or their combination.. We also measured cAMP levels and phosphorylation of the cAMP response element binding protein (CREB). As single components, carbachol, olodaterol and tiotropium did not affect IL-6 and IL-8 release. Carbachol concentration-dependently enhanced the production of IL-1β-induced IL-6 and IL-8, which was blocked by the simultaneous addition of tiotropium. The combination of olodaterol plus tiotropium further reduced IL-6 and IL-8 release. Olodaterol induced cAMP and the phosphorylation of CREB, an effect counteracted by carbachol, but rescued by tiotropium. We conclude that olodaterol plus tiotropium cooperate to decrease the inflamamtory response in pulmonary fibroblasts in vitro.
    Pulmonary Pharmacology &amp Therapeutics 11/2013; 27(1). DOI:10.1016/j.pupt.2013.11.001 · 2.57 Impact Factor
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    • "explanation for the observed increase of BSM bundles surrounding the bronchi of asthma patients [21]. We have extensively explored the role of the CEBP transcription factor-family in BSM cell proliferation and concluded that the expression and regulation of C/EBPα isoforms may be crucial to understand the proliferation control of BSM cells [4] [5] [12] [13]. In our present study, we demonstrated that normal BSM cells express C/EBPα (p42) and C/EBPα (p30) isoforms, as well as their specific translation regulator calreticulin. "
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    ABSTRACT: Background. Calreticulin controls the C/EBPαp42/p30 at the translational level trough a cis-regulatory CNG rich loop in the CEBPA mRNA. We determined the effects of steroids and long-acting beta-agonists on the p42/p30 ratio and on calreticulin expression in primary human bronchial smooth muscle (BSM) cells. Methods. The effects of budesonide (10(-8) M) and formoterol (10(-8) M) were studied in BSM cells pre-treated with siRNA targeting calreticulin. The expression of C/EBPα and calreticulin was determined by immuno-blotting. Automated cell counts were performed to measure proliferation. Results. All tested BSM cell lines (n = 5) expressed C/EBPα and calreticulin. In the presence of 5% FBS, the p42/p30 ratio significantly decreased (n = 3, P < 0.05) and coincided with BSM cell proliferation. High levels of calreticulin were associated with a decreased p42/p30 isoform ratio. FBS induced the expression of calreticulin (n = 3, P < 0.05), which was further increased by formoterol. siRNA targeting calreticulin increased the p42/p30 ratio in non-stimulated BSM cells and significantly inhibited the proliferation of PDGF-BB-stimulated BSM cells (n = 5, P < 0.05). Neither budesonide nor formoterol restored the p42 isoform expression. Conclusions. Our data show calreticulin is a negative regulator of C/EBPα protein expression in BSM cells. Modulation of calreticulin levels may provide a novel target to reduce BSM remodeling.
    Journal of Allergy 02/2012; 2012:783290. DOI:10.1155/2012/783290
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    • "Furthermore, this may link the C/EBP-a deficiency to nutrition, lipid, vitamin and calcium metabolism, all of which have been linked to asthma (Raught et al., 2004; Lian et al., 2008). Modulation of the translation of C/EBP-a in asthma patients may provide a novel therapeutic strategy which may cure the disease; however, none of the existing asthma drugs exhibit this property (Roth et al., 2004; Borger et al., 2007). "
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