Late Breaking Abstract - Activation of regenerative pathways by physical exercise in patients with chronic obstructive pulmonary disease

Guidelines recommend exercise for patients with COPD, but molecular effects in the lung are not well understood. Our project aims to evaluate biomarkers in blood samples to assess regenerative processes, inflammation, and stem cell activity after exercise intervention and to understand lung regeneration mechanisms in in vitro studies. We hypothesize that structural changes in the lung affect regenerative capacity, dependent on COPD phenotype. <bold>Method:</bold> Ex-smoking COPD patients (n=54) with FEV1 30-80% predicted underwent a 12-week aerobic- and muscle strengthening intervention. For all subjects, data were collected through clinical examinations, HRCT, lung function, physical capacity, symptom questionnaires, and blood samples. The cohort was phenotyped and subdivided by a theoretical baseline threshold of 320µm airspace radius (rAiDA) measured by Airway Dimension Assessment (AiDA) to indicate a more emphysematous lung. <bold>Preliminary results:</bold> Recruitment is ongoing. After intervention, 30 subjects (55%) with baseline rAiDA<320µm had stable or at least 5% decrease of airspace radius and 91% had increased FEV1 (>5%). Of those with an rAiDA>320µm, 85% had stable or decreased airspace and 85% had increased FEV1. In addition, a pilot proteomic analysis on serum (n=5) revealed increased concentrations of proteins related to regeneration, inflammation, and ECM remodeling, e.g. hepatocyte growth factor (36%), IL-10 (46%) and decorin (25%), but a decrease in fibroblast growth factor 2 (21%) after the intervention. Our preliminary findings indicate that exercise had measurable effects in both subgroups of AiDA and seem to activate both remodeling and inflammatory signaling pathways.