Investigation on the Distribution and Expression of Caveolin-1 in Endothelial Cells under Disturbed Shear Stress by Vertical-Step Flow Chamber

Abstract

Previous researches suggested that caveolae and Caveolin-1 (Cav-1) may regulate the vascular response to lamina shear stress alter. However, atherosclerosis (AS) preferentially affected at the outer edges of vessel bifurcations, where the flow patterns are disturbed. In this study, we fabricated a novel PDMS-based vertical-step flow chamber, which mimics the disturbed shear flow in AS preferential area of the artery to study the changes of Cav-1 in endothelial cell. Cells were seeded into the flow channel, and then exposed to disturbed shear stress (about 40 dynes/cm²) for 6 hours, 12 hours, 24 hours and 48 hours. It was found that in disturbed flow area, Cav-1 distribution shifted to the membrane from cytoplasm. In early stage of the stimulation, the expression of the Cav-1 decreased both on mRNA and protein level. The expression of Cav-1 in EC showed a significant decrease about 40% after exposure to shear stress for 48 hours. It suggests that disturbed shear stress can affect the distribution and expression of caveolin-1 in endothelial cell, which might play an important role in transducing mechanical stimuli into intracellular signals to causes ECs pathological changes and finally it might deduce into atheromatosis process.