Oxidative stress-induced mitochondrial dysfunction drives inflammation and airway smooth muscle remodeling in patients with chronic obstructive pulmonary disease.

TitleOxidative stress-induced mitochondrial dysfunction drives inflammation and airway smooth muscle remodeling in patients with chronic obstructive pulmonary disease.
Publication TypeJournal Article
Year of Publication2015
AuthorsWiegman, CH, Michaeloudes, C, Haji, G, Narang, P, Clarke, CJ, Russell, KE, Bao, W, Pavlidis, S, Barnes, PJ, Kanerva, J, Bittner, A, Rao, N, Murphy, MP, Kirkham, PA, Chung, KFan, Adcock, IM
Corporate Authors
JournalJ Allergy Clin Immunol
Date Published2015 Sep
KeywordsAdult, Aged, Airway Remodeling, Animals, Antioxidants, Bronchial Hyperreactivity, Electron Transport Chain Complex Proteins, Female, Gene Expression Regulation, Humans, Hydrogen Peroxide, Male, Membrane Potential, Mitochondrial, Mice, Middle Aged, Mitochondria, Muscle, Smooth, Myocytes, Smooth Muscle, Organophosphorus Compounds, Oxidative Stress, Ozone, Pneumonia, Pulmonary Disease, Chronic Obstructive, Reactive Oxygen Species, Respiratory System, Signal Transduction, Smoking, Ubiquinone

BACKGROUND: Inflammation and oxidative stress play critical roles in patients with chronic obstructive pulmonary disease (COPD). Mitochondrial oxidative stress might be involved in driving the oxidative stress-induced pathology.OBJECTIVE: We sought to determine the effects of oxidative stress on mitochondrial function in the pathophysiology of airway inflammation in ozone-exposed mice and human airway smooth muscle (ASM) cells.METHODS: Mice were exposed to ozone, and lung inflammation, airway hyperresponsiveness (AHR), and mitochondrial function were determined. Human ASM cells were isolated from bronchial biopsy specimens from healthy subjects, smokers, and patients with COPD. Inflammation and mitochondrial function in mice and human ASM cells were measured with and without the presence of the mitochondria-targeted antioxidant MitoQ.RESULTS: Mice exposed to ozone, a source of oxidative stress, had lung inflammation and AHR associated with mitochondrial dysfunction and reflected by decreased mitochondrial membrane potential (ΔΨm), increased mitochondrial oxidative stress, and reduced mitochondrial complex I, III, and V expression. Reversal of mitochondrial dysfunction by the mitochondria-targeted antioxidant MitoQ reduced inflammation and AHR. ASM cells from patients with COPD have reduced ΔΨm, adenosine triphosphate content, complex expression, basal and maximum respiration levels, and respiratory reserve capacity compared with those from healthy control subjects, whereas mitochondrial reactive oxygen species (ROS) levels were increased. Healthy smokers were intermediate between healthy nonsmokers and patients with COPD. Hydrogen peroxide induced mitochondrial dysfunction in ASM cells from healthy subjects. MitoQ and Tiron inhibited TGF-β-induced ASM cell proliferation and CXCL8 release.CONCLUSIONS: Mitochondrial dysfunction in patients with COPD is associated with excessive mitochondrial ROS levels, which contribute to enhanced inflammation and cell hyperproliferation. Targeting mitochondrial ROS represents a promising therapeutic approach in patients with COPD.

Alternate JournalJ. Allergy Clin. Immunol.
Citation Key10.1016/j.jaci.2015.01.046
PubMed ID25828268
PubMed Central IDPMC4559140
Grant ListG1001367 / / Medical Research Council / United Kingdom
MC_U105663142 / / Medical Research Council / United Kingdom
093080/Z/10/Z / / Wellcome Trust / United Kingdom