Aerobic Exercise Attenuates Airway Inflammatory Responses in a Mouse Model of Atopic Asthma

Abstract

Recent reports indicate that aerobic exercise improves the overall physical fitness and health of asthmatic patients. The specific exercise-induced improvements in the pathology of asthma and the mechanisms by which these improvements occur, however, are ill-defined; thus, the therapeutic potential of exercise in the treatment of asthma remains unappreciated. Using an OVA-driven mouse model, we examined the role of aerobic exercise in modulating inflammatory responses associated with atopic asthma. Data demonstrate that moderate intensity aerobic exercise training decreased leukocyte infiltration, cytokine production, adhesion molecule expression, and structural remodeling within the lungs of OVA-sensitized mice (n = 6–10; p < 0.05). Because the transcription factor NF-κB regulates the expression of a variety of genes that encode inflammatory mediators, we monitored changes in NF-κB activation in the lungs of exercised/sensitized mice. Results show that exercise decreased NF-κB nuclear translocation and IκBα phosphorylation, indicating that exercise decreased NF-κB activation in the lungs of sensitized mice (n = 6). Taken together, these results suggest that aerobic exercise attenuates airway inflammation in a mouse model of atopic asthma via modulation of NF-κB activation. Potential exists, therefore, for the amelioration of asthma-associated chronic airway inflammation through the use of aerobic exercise training as a non-drug therapeutic modality.

Aerobic conditioning and allergic pulmonary inflammation in mice. II. Effects on lung vascular and parenchymal inflammation and remodeling

“…In previous studies, our and other groups have observed that low-and moderate-intensity aerobic exercise specifically decreases airway eosinophilic inflammation and remodeling (40,41,61). Recently, we demonstrated that low-and moderateintensity aerobic training decreases airway inflammation and remodeling in an experimental model of chronic allergic lung inflammation in mice and that these effects are not mediated by increased Th 1 response but could be partially mediated by increased interleukin (IL)-10 expression (61).…”

Effects of exercise training on atrophy gene expression in skeletal muscle of mice with chronic allergic lung inflammation

“…In spite of the well-described effects of aerobic training of moderate intensity in eliciting anti-inflammatory effects in asthma (21,24), no information is available regarding the effects of training on peripheral skeletal muscle in this disease. Previous studies have demonstrated that this type of exercise may be used to prevent muscle atrophy under disuse conditions (32,33).…”

“…A corollary was that aerobic physical training applied before the induction of chronic allergic lung inflammation could reduce these effects. Since different intensities of aerobic training may induce different adaptations in the asthmatic inflammatory response (21,24,25), we analyzed the effect of two aerobic treadmill training intensities in the present study.…”

Has Aerobic Exercise Anti-inflammatory Effect for Asthma?

“…In this direction, since 2004 a growing number of experimental studies using mouse models of chronic allergic airway inflammation have demonstrated that low and moderate intensity aerobic exercise performed either before, during or after the allergen sensitization results in decreased eosinophilic inflammation, Th2 cytokines production, airway remodeling and hyperresponsiveness [16][17][18][19][20][21][22][23][24]. Shortly, these studies have demonstrated that these beneficial effects can be attributed to decreased activation of leukocytes and bronchial epithelial cells as a result of increased activation of glucocorticoids receptors, T-regulatory cells resulting in increased synthesis of anti-inflammatory cytokine IL-10, and decreased activation of transcriptional factor NF-kB [16][17][18][19][20][21][22][23][24].…”

“…Shortly, these studies have demonstrated that these beneficial effects can be attributed to decreased activation of leukocytes and bronchial epithelial cells as a result of increased activation of glucocorticoids receptors, T-regulatory cells resulting in increased synthesis of anti-inflammatory cytokine IL-10, and decreased activation of transcriptional factor NF-kB [16][17][18][19][20][21][22][23][24]. In addition, these studies also demonstrated that aerobic exercise present a direct inhibitory effect on the pulmonary oxidants production as well as on the synthesis of mediators involved in the airway remodeling process [19,24].…”