Stretch-activated calcium mobilization in airway smooth muscle and pathophysiology of asthma

Excessive mechanical stresses and altered mechanically activated signal pathways in the airway are involved in the mechanisms of asthma pathogenesis. Activation of airway smooth muscle (ASM) cells is a major source of mechanical stimuli of asthmatic airways. Ca 2+ is one of the diverse second messengers for ASM cell functions such as contraction and migration. Ca 2+ influx pathway activated by mechanical stretch regulates mechanotransduction of ASM cells. However, molecules for mechanically activated ion channels (e.g. Piezo1, Piezo2) responsible for Ca 2+ mobilization have yet to be identified in ASM cells. This review primarily focuses on Ca 2+ signaling activated by mechanical stretch in ASM cells and roles of mechanical stresses in pathophysiology of asthma.