Exercise normalizes alveolar exosomes in smoke-exposed mice

Pulmonary and circulating extracellular vesicles (EV), including exosomes, are increased by cigarette smoking and implicated in COPD pathogenesis. Exercise, a component of pulmonary rehabilitation, increases circulating EVs and anti-inflammatory signaling. The effect of exercise on smoke-induced EV release and immunomodulation is not known. 40 C57BL mice were exposed to air or daily cigarette smoke (10 cigarettes/day) for 4 months. At 4 months, 10 from each group ran for 1 hour while others rested; within 20 min serum and bronchoalveolar lavage fluid (BALF) were collected. CD63+/TSG101+ EVs were isolated by immunoprecipitation and quantified by nanoparticle tracking analysis. Inflammatory markers were measured in serum EVs by multiplex. Smoke increased EVs in serum (38%) and BALF (72%). In smoke-exposed mice, exercise further increased EVs in serum (25%), but reduced EVs in BALF (58%) (Figure). Smoke reduced (p Smoking increased circulating and alveolar EVs and altered exercise-induced inflammatory signaling within circulating EVs. One exercise bout normalized alveolar EV concentration, and increased circulating EVs. This suggests a potential benefit of exercise on EV-associated alveolar pathogenesis. Support: TRDRP 28FT-001