A synergistic effect of wall shear stress and impinging jet velocity on vascular endothelial cell morphology and actin cytoskeleton

抄録

Abnormal blood jet flow impinging on the aortic wall has been implicated in the pathogenesis of aortic diseases. We have previously reported damage to the integrity of cultured vascular endothelial cells (ECs) exposed to a vertical impinging flow condition where both wall shear stress (WSS) and normal flow velocity immediately above the wall were high. However, it remains unclear whether the changes in ECs were caused by one factor or a combination of both. In this study, we newly designed an “inclined” impinging flow chamber to generate high WSS and high normal flow velocity conditions in different regions and examined the changes in EC morphology and actin cytoskeletal structure to the flow condition. Our findings revealed that high WSS or high normal velocity alone did not cause noticeable morphological and actin cytoskeletal changes in human aortic ECs. On the other hand, ECs exposed to the combination of both factors under a vertical impinging flow condition exhibited orientated morphology and developed actin filaments perpendicular to the direction of flow. The results suggest that high WSS or high normal velocity alone did not, but the combination of both factors led to distinct cell morphological responses in ECs.