Publications by authors named "Petra Seidel"

Therapeutic targets in asthma are reduction of airway inflammation and remodelling, the latter is not affected by available drugs. Here we present data that inhibition of MAPK-activated protein kinase (MNK)-1 reduces inflammation and remodelling. MNK-1 regulates protein expression by controlling mRNA stability, nuclear export and translation through the eukaryotic initiation factor 4E (eIF4E).

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Background: Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with poor prognosis. The kinase inhibitor nintedanib specific for vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR) and fibroblast growth factor receptor (FGFR) significantly reduced the rate of decline of forced vital capacity versus placebo.

Aim: To determine the in vitro effect of nintedanib on primary human lung fibroblasts.

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Sphingosine 1-phosphate (S1P) is a bioactive sphingolipid that plays an important proinflammatory role in asthmatic airways. Corticosteroids are first-line antiinflammatories in asthma; however, their repressive effects on S1P-induced cytokine secretion have not been investigated. To address this, our in vitro study reveals the molecular mechanisms by which corticosteroids inhibit S1P-induced IL-6 expression in the pivotal immunomodulatory cell type, airway smooth muscle (ASM).

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Asthma is a chronic inflammatory disease of the airways, which results from the deregulated interaction of inflammatory cells and tissue forming cells. Beside the derangement of the epithelial cell layer, the most prominent tissue pathology of the asthmatic lung is the hypertrophy and hyperplasia of the airway smooth muscle cell (ASMC) bundles, which actively contributes to airway inflammation and remodeling. ASMCs of asthma patients secrete proinflammatory chemokines CXCL10, CCL11, and RANTES which attract immune cells into the airways and may thereby initiate inflammation.

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Background: Activated mast cells are present within airway smooth muscle (ASM) bundles in eosinophilic asthma. ASM production of the chemokine CXCL10 plays a role in their recruitment. Thus the effects of glucocorticoids (fluticasone, budesonide), long-acting β2-agonists (salmeterol, formoterol) and thiazolidinediones (ciglitazone, rosiglitazone) on CXCL10 production by ASM cells (ASMC) from people with and without asthma were investigated in vitro.

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CXCL10 stimulates mast cell infiltration into airway smooth muscle bundles and, thus, activate cytokine secretion and airway smooth muscle cell (ASMC) proliferation. Dimethylfumarate (DMF) reduces cytokine secretion by lymphocytes and ASMC proliferation through haem oxygenase (HO)-1. Therefore, we investigated the potency of DMF to inhibit tumour necrosis factor (TNF)-α- and interferon (IFN)-γ-induced CXCL10 secretion by human ASMCs.

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Hyperplasia of airway smooth muscle (ASM) is a feature of the remodelled airway in asthmatics. We examined the antiproliferative effectiveness of the corticosteroid dexamethasone on expression of the key regulator of G(1) cell cycle progression-cyclin D1-in ASM cells from nonasthmatics and asthmatics stimulated with the mitogen platelet-derived growth factor BB. While cyclin D1 mRNA and protein expression were repressed in cells from nonasthmatics in contrast, cyclin D1 expression in asthmatics was resistant to inhibition by dexamethasone.

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Airway inflammation and respiratory infections are important factors contributing to disease exacerbation in chronic airway diseases such as asthma and chronic obstructive pulmonary disease. Airway smooth muscle (ASM) cells express Toll-like receptors (TLRs) and may be involved in the amplification of airway inflammatory responses during infectious exacerbations. We determined whether infectious stimuli (mimicked using Pam3CSK4, a synthetic bacterial lipopeptide that binds to TLR2/TLR1) further enhance ASM cell inflammatory responses to TNFα in vitro and the signaling pathways involved.

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Airway smooth muscle (ASM) plays an important immunomodulatory role in airway inflammation in asthma. In our previous in vitro studies in ASM cells delineating the pro-inflammatory mitogen-activated protein kinase (MAPK) signaling pathways activated by tumor necrosis factor α (TNFα), we observed that TNFα concomitantly induces the rapid, but transient, upregulation of the anti-inflammatory protein-mitogen-activated protein kinase phosphatase 1 (MKP-1). As this was suggestive of a negative feedback loop, the aim of this study was to investigate the molecular mechanisms of MKP-1 upregulation by TNFα and to determine whether MKP-1 is a negative feedback effector that represses MAPK-mediated pro-inflammatory signaling pathways and cytokine secretion in ASM cells.

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Unlabelled: QUESTION UNDER STUDY/PRINCIPLES: Dimethylfumarate (DMF) had been reported to reduce asthma symptoms and to improve the quality of life of asthma patients. Therefore, we assessed the anti-inflammatory and anti-remodeling effect of DMF on isolated lung fibroblasts, which are relevant to inflammatory lung diseases. We determined the effect of DMF on platelet derived growth factor (PDGF)-BB induced proliferation, as well as on PDGF-BB and tumor necrosis factor (TNF)-α induced interleukin (IL)-6 secretion and on activation of activated protein (AP)-1 and nuclear factor kappaB (NF-ĸB).

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Background: Airway wall remodelling is an important pathology of asthma. Growth factor induced airway smooth muscle cell (ASMC) proliferation is thought to be the major cause of airway wall thickening in asthma. Earlier we reported that Dimethylfumarate (DMF) inhibits platelet-derived growth factor (PDGF)-BB induced mitogen and stress activated kinase (MSK)-1 and CREB activity as well as IL-6 secretion by ASMC.

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