Background And Purpose: Toluene diisocyanate (TDI)-induced asthma is characterized by mixed inflammation dominated by neutrophils, and is refractory to steroid treatment. Neutrophil extracellular traps (NETs) play an important role in severe asthma, but their role in TDI-induced asthma models is unclear. This study focused on the role and mechanism of NETs in steroid-resistant TDI-induced asthma.
Methods: Induced sputum was collected from 85 asthmatic patients and 25 healthy controls to detect eDNA. A murine TDI-induced asthma model was prepared, and asthmatic mice were given dexamethasone or DNase I. In vitro, the human bronchial epithelial cell line HBE was stimulated with NETs or TDI-human serum albumin (TDI-HSA).
Results: Asthma patients had higher sputum eDNA compared to healthy subjects. In asthma patients, eDNA was positively correlated with sputum neutrophils, and negatively correlated with FEV1%predicted. Airway inflammation, airway reactivity, Th2 cytokine levels in lymph supernatant, and levels of NETs were significantly increased in the TDI-induced asthmatic mice. These increases were suppressed by DNase I, but not by dexamethasone. Inhibition of NETs improved interleukin (IL)-8 and MKP1 mRNA expression, and reduced phosphorylation of GR-S226 induced by TDI. Inhibition of NETs improved airway epithelial barrier disruption, as well as p38 and ERK signaling pathways in TDI-induced asthmatic mice. In vitro, NETs promoted the expression of IL-8 mRNA in HBE cells, and reduced the expression of MKP1. IL-8 elevation induced by NETs was suppressed by a p38 inhibitor or ERK inhibitor, but not by dexamethasone. Pretreatment with RAGE inhibitor reduced NETs induced p38/ERK phosphorylation and IL-8 levels in HBE cells.
Conclusion: Our data suggest that targeting NETs might effectively improved TDI-induced airway inflammation and airway epithelial barrier function. This may potentially be a treatment for patients with steroid-resistance asthma.
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http://dx.doi.org/10.1016/j.intimp.2023.109719 | DOI Listing |
Free Radic Biol Med
January 2025
Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, 510515, China. Electronic address:
Environ Pollut
December 2024
Clinical Medical School, Guizhou Medical University, Guiyang, Guizhou, 561113, China.
Toluene diisocyanate (TDI) is a major industrial compound that induces occupational asthma with steroid-resistant properties. Recent studies suggest that the gastrointestinal tract may be an effective target for the treatment of respiratory diseases. However, the alterations of the gut-lung axis in TDI-induced asthma remain unexplored.
View Article and Find Full Text PDFBiomed Pharmacother
August 2024
Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China. Electronic address:
Mitochondrial dysfunction is critical in the pathogenesis of asthma. Mitochondrial permeability transition pore (mPTP) regulates the release of mitochondrial damage-associated molecular patterns (mtDAMPs) to maintain mitochondrial homeostasis. Bongkrekic acid (BKA) is a highly selective inhibitor of mPTP opening, participates the progression of various diseases.
View Article and Find Full Text PDFJ Asthma
November 2024
Department of Pulmonary and Critical Care Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China.
Objective: Down-regulation of bronchial epithelial E-cadherin is an important of feature of severe asthma, including steroid-insensitive asthma. Yet, the mechanisms involved in E-cadherin disruption are not fully understood. This study was aimed to investigate the role of glucose transporter 1 (GLUT1) in dysregulation of E-cadherin in toluene diisocyanate (TDI)-induced steroid-insensitive asthma.
View Article and Find Full Text PDFRedox Biol
April 2024
Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, China. Electronic address:
Background: Extracellular high mobility group box 1 (HMGB1) is a key mediator in driving allergic airway inflammation and contributes to asthma. Yet, mechanism of HMGB1 secretion in asthma is poorly defined. Pulmonary metabolic dysfunction is recently recognized as a driver of respiratory pathology.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!