New Insights in the Actin Cytoskeleton Dynamics of the Sonoporated Human Umbilical Vein Endothelial Cells

The aim of this study is to investigate how the actin cytoskeleton responds to the sonoporation, and how the disturbed actin cytoskeleton restores to initial physiological status. Using a customized platform for 1.5-MHz ultrasound exposure (13.33-μs duration and 0.70-MPa peak negative pressure)and observing the dynamics of disruption and restoration of actin cytoskeleton and plasma membrane. Our results revealed: 1)The disruption and recovery of actin cytoskeleton at the sonoporation site, was temporally synchronized with the localized perforation and resealing of plasma membrane. 2)We observed the area of disruption site became larger in the first tens of seconds, then globular actin polymers directionally migrated to the disruption site along fibrous actin, accumulated and aggregated to patch the disruption site on the time scale of tens of seconds to minutes (30 s-10 min). 3)The resealing time of the disrupted actin cytoskeleton was related to the disruption degree of the sonoporaion, and actin cytoskeleton would fail to restore for irreversible sonoporation or in the absence of extracellular calcium ion. These findings provide new insight into the biological response to sonoporation.