Aged human airway tissue modeling and analysis using coupled mechanics *JongWon-Kim,

Aging affects the human airway by changing its morphology and tissue material properties post generation 14 (G14). The airway tissue strains responsible for stressing and rupturing the lung’s fiber network have been previously measured experimentally by several researchers. However, the strains on airway tissue due to aging have not been extensively studied. In this study, a computational tissue model that incorporates the heterogeneity of the airways was developed to study the effects of tissue material properties on strain distribution within each layer of the airway tissue. The boundary conditions for tissue analysis were obtained from the whole lung model under mechanical ventilation. The results obtained from the tissue analysis demonstrated a higher strain in the epithelium rather than smooth muscle layer, and the stresses in each tissue layer of a 70 year-old are approximately 7% higher than those of a 50 yearold. Additionally, a lower strain level (approximately 1.5%) was found in the tissue layer of the 70 year-old as compared to a 50 year-old (approximately 2.0%). The pattern of increasing strain levels with aging obtained from the tissue analysis is significant because it suggests that strains at the cellular-level can create inflammatory responses, thus damaging airway tissues.