Low shear stress induces inflammatory response via CX3CR1/NF-κB signal pathway in human umbilical vein endothelial cells

Abstract

Purpose Low shear stress has been reported to induce atherosclerosis. In the present study,the objective of our study is the comprehensive identification of CX3CR1 / NF-κB signaling pathway involved in low shear stress( LSS) -induced inflammation in HUVECs through protein profiling and cell function experiment.Methods Human umbilical vein endothelial cell was cultured onglass slides and placed in a parallel plate flow chamber. M199 culture medium was used for low laminar shear stress at 4. 14 dyn/cm2, 2 h for the testing group, CX3CR1 sh-RNA and NF-κB inhibitor PDTC are used to block the effects of CX3CR1 and P65. The expression levels of the protein were determined by western blot analysis. Mononuclear cell adhesion assays and scratch assays are used to detect cell adhesion and migration.Results Western blotting analyses revealed that compared with the controls，there is a significant increase in the expression of CX3CR1, nucleusP65,intercellular adhesion molecule-1( ICAM-1), vascular cell adhesion molecule-1 ( VCAM-1) and Interleukin-6( IL-6), while the expression of cytosolic P65 and IκB was significantly reduced in human umbilical vein endothelial cells ( HUVECs) treated with LSS. CX3CR1 Sh－RNA was use to reveal its effect on LSS-in-duced inflammation. Further, specific NF-κB P65 inhibitors( PDTC) were used to reveal the downstream NF-κB P65 exclusively involved in LSS-induced inflammation in HUVECs, this effect can be abrogated by CX3CR1 sh-RNA and NF-κB inhibitors. Monocyte adhesion assay and scratch test revealed LSS promotes adhesion of monocytes and migration of cells, this effect can be abrogated by CX3CR1 sh-RNA and NF-κB inhibitors. LSS is involved in the expression of adhesion molecules and chemokines, which are important for the initiation of endothelial inflammation-related atherosclerosis.Conclusions The activation of CX3CR1 /NF-κB signaling pathway induced by low shear stress in endothelial cells may lead to the future therapeutic targets of atherosclerotic inflammation.