Effects of Fluid Shear Stress on PCP Signaling Pathway and Ciliogenesis in Vascular Endothelial Cells / 医用生物力学

ABSTRACT

Objective To investigate the effect of different fluid shear stress (FSS) on the regulation of planar cell polarity (PCP) signaling, and further to explore the relationship among FSS, PCP signaling pathway and ciliogenesis. Methods The hydrodynamic cell model of adjustable FSS was established. qPCR and immunofluorescence were used to detect the mRNA expression of PCP signaling pathway core protein Dvl2 and cilia assembly protein IFT88, cell targeting and co-localization under different FSS. Western blot (WB) was used to detect the protein expression of Dvl2 at 18 h under different FSS. Results The qPCR result showed that compared with 1.5 Pa FSS, under 0.1 Pa FSS, the mRNA expression of Dvl2 was higher at 6 h and 18 h (P＜0.05), significantly higher at 12 h (P＜0.01); the mRNA expression of IFT88 was significantly higher at 18 h (P＜0.01). The WB result showed that compared with 0 h, under 0.1 Pa FSS, the protein expression of Dvl2 was higher at 18 h (P＜0.05), significantly lower under 1.5 Pa FSS (P＜0.01); compared with 1.5 Pa FSS, the protein expression of Dvl2 was higher at 18 h under 0.1 Pa FSS (P＜0.05). The immunofluorescence result showed that the positive expression of Dvl2 increased with the loading time on FSS increasing, and gradually aggregated at a point around the nucleus; the positive expression of IFT88 was gradually transferred from the nucleus to the cytoplasm and aggregated at a point under 0.1 Pa FSS, and gradually decreased and depolymerized under 1.5 Pa FSS. Protein Dvl2 and IFT88 were located in the same position in cells under 0.1 Pa FSS and before 18 h under 1.5 Pa FSS, and colocalization of proteins Dvl2 and IFT88 was not observed after 18 h under 1.5 Pa FSS due to IFT88 depolymerization. Conclusions Laminar FSS played an inhibition on the transduction of PCP signaling pathway and a hindrance on the process of ciliogenesis, while low FSS played a promotion on the transduction. PCP signaling pathway might regulate FSS-induced ciliogenesis by Dvl2.