Effects of exercise on lung inflammation in ovalbumin-sensitized and single challenged mice

Background : Studies suggest that physical exercise reduces lung function decline and risk of exacerbations in asthmatic patients. However, the inflammatory lung response involved in exercise during sensitization remains unclear. Aims : To evaluate the effects of aerobic exercise in an experimental model of sensitization and single ovalbumin (OVA) challenge. Methods : Male Swiss mice were divided into 4 groups: mice non-sensitized, non-exposed to OVA or exercise (Control, n=7); animals submitted to moderate treadmill exercise (Exercise, n=6); animals sensitized (OVA 10 µg) and single exposed to aerosolized OVA 1% (30 min) (OVA, n= 6) and animals sensitized, submitted to exercise and single exposed to OVA (OVA+Ex, n=6). 24 hours after a single OVA/saline exposure, anesthetized mice were euthanized and we performed measures of inflammatory cells from bronchoalveolar fluid (BALF), IL-4, IL-5, IL-10, IL-1ra from lung tissue by enzyme-linked immunosorbent assay and qualitative measures of IgG1 and IgE OVA-specific by Passive Cutaneous Anaphylaxis. Results : Exercise decreased total number of cells, as well as eosinophils, neutrophils, lymphocytes and macrophages from BALF in OVA+Ex group (p Conclusion : Our results showed that aerobic physical exercise attenuated the acute lung inflammatory response induced by a single OVA-challenge in sensitized mice, suggesting immunomodulatory properties of exercise on sensitization process in asthma.