Bronchoconstriction: a potential missing link in airway remodelling

Abstract

In asthma, progressive structural changes of the airway wall are collectively termed airway remodelling. Despite its deleterious effect on lung function, airway remodelling is incompletely understood. As one of the important causes leading to airway remodelling, here we discuss the significance of mechanical forces that are produced in the narrowed airway during asthma exacerbation, as a driving force of airway remodelling. We cover in vitro, ex vivo and in vivo work in this field, and discuss up-to-date literature supporting the idea that bronchoconstriction may be the missing link in a comprehensive understanding of airway remodelling in asthma.

Keywords: airway remodelling; asthma; bronchoconstriction; mechanical stress.

Figure 1.

Increased cellular velocity and cell shape elongation are characteristics of the unjammed layer. (a) Representative speed maps show the differences in cellular velocities between jammed and unjammed layers. The cellular velocity is increased in the unjammed layer, which is induced by mechanical compression. (b) The theory developed by the vertex model predicted cell shape changes during the phase transition between the jammed and unjammed layers. Predicted cell shape is cobblestone-like in the jammed layer, while it is elongated in the unjammed layer. Figure from [40] with the permission from the publisher.

Figure 2.

Unjamming transition is induced by ionizing radiation. (a) Representative speed maps show the differences in cellular velocities between jammed and unjammed layers. The cellular velocity is increased in the unjammed layer, which is induced by ionizing radiation. Scale bar, 100 μm. (b) Phalloidin staining from the corresponding cells above show the differences in cell shape between jammed and unjammed layers. HBE cells maintain a cobblestone-like shape in the jammed layer, whereas become elongated shape in the unjammed layer. Figure from [59] with the permission from the publisher.