Oxidative stress in asthma: a distinct clinical and pathologic feature?

Asthma is a type of chronic airway inflammation. Corticosteroids are inadequate for asthma therapy. However, it remains unclear whether oxidative stress is a distinct clinical and pathologic feature in asthma. We reviewed the articles on asthma-associated oxidative stress. The exposures to airborne allergens, such as house dust mite (HDM) and birch pollen, may not only trigger innate and adaptive immune responses but also cause oxidative stress damage in the airways. Allergen-induced reactive oxygen species (ROS) is involved in p38 MAPK, phosphoinositide-3-kinase (PI3K)/Akt and nuclear factor erythroid 2-related factor (Nrf2) kinase pathway signaling. Airborne particulate matter (PM) is an important environmental contaminant and is related to asthma development through increasing oxidative stress in the airways. Whether oxidative stress status is associated with the degree of asthma is needed to be further studied. Oxidative stress-induced corticosteroid insensitivity was associated with p38 MAPK, PI3K/Akt and Nrf2 signaling, and inhibited histone deacetylase 2 (HDAC2) activity and corticosteroid receptor (GR) function. Antioxidant treatments may be useful for oxidative stress in asthma.