Περίληψη:
Introduction: Resistive breathing (RB), the pathophysiologic hallmark of chronic obstructive pulmonary disease (COPD), especially during exacerbations, is associated with significant inflammation and mechanical stress on the lung. Mechanical forces are implicated in the progression of emphysema that is a major pathologic feature of COPD. We hypothesized that resistive breathing exacerbates emphysema. Methods: C57BL/6 mice were exposed to 0.75 units of pancreatic porcine elastase intra-tracheally to develop emphysema. Resistive breathing was applied by suturing a nylon band around the trachea to reduce surface area to half for the last 24 or 72 hours of a 21-day time period after elastase treatment in total. Following RB (24 or 72 hours), lung mechanics were measured and bronchoalveolar lavage (BAL) was performed. Emphysema was quantified by the mean linear intercept (Lm) and the destructive index (DI) in lung tissue sections. Results: Following 21 days of intratracheal elastase exposure, Lm and DI increased in lung tissue sections [Lm (μm), control 39.09±0.76, elastase 62.05±2.19, p=0.003 and DI, ctr 30.95 ±2.75, elastase 73.12±1.75, p<0.001]. RB for 72 hours further increased Lm by 64% and DI by 19%, compared to elastase alone (p<0.001 and p=0.02, respectively). RB induced BAL neutrophilia in elastase-treated mice. Static compliance (Cst) increased in elastase-treated mice [Cst (mL/cmH2O), control 0.067±0.001, elastase 0.109±0.006, p<0.001], but super-imposed RB decreased Cst, compared to elastase alone [Cst (mL/cmH2O), elastase+RB24h 0.090±0.004, p=0.006 to elastase, elastase+RB72h 0.090±0.005, p=0.006 to elastase]. Conclusion: Resistive breathing augments pulmonary inflammation and emphysema in an elastase-induced emphysema mouse model. © 2020 Toumpanakis et al.
Συγγραφείς:
Toumpanakis, D.
Mizi, E.
Vassilakopoulou, V.
Dettoraki, M.
Chatzianastasiou, A.
Perlikos, F.
Giatra, G.
Moscholaki, M.
Theocharis, S.
Vassilakopoulos, T.
Λέξεις-κλειδιά:
nylon; pancreatic elastase, adult; airway resistance; animal cell; animal experiment; animal model; animal tissue; Article; breathing rate; comparative study; controlled study; disease course; elastase-induced emphysema; lung lavage; lung mechanics; lung parenchyma; male; mouse; nonhuman; pneumonia; surface area; airway resistance; animal; C57BL mouse; chronic obstructive lung disease; disease model; emphysema; lung; lung emphysema; pig, Airway Resistance; Animals; Disease Models, Animal; Emphysema; Lung; Mice; Mice, Inbred C57BL; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Swine
