Abstract: Objective To explore the effect of quercetin(Que)on TNF-α-induced inflammation of vascular smooth muscle cells (VSMCs) and potential mechanism. Methods Mouse aortic vascular smooth cell line MOVAS was exposed to different concentrations of quercetin and the cytotoxicity of quercetin was detected by CCK8 method; TNF-α was used to induce inflammation of MOVAS cells from patients with Kawasaki disease(KO). Cells were exposed to quercetin and NF-κB p65 inhibitors, mRNA and protein expression of inflammatory factors VCAM-1, ICAM-1, MCP-1, IL-1β, IL-6, channel protein NF-κB p65 and phosphorylated NF-κB p65 were detected by RT-qPCR and Western blot; BCECF-AM fluorescent probe was used to detect the adhesion ability of monocytes (THP-1) to MOVAS cells; Immunofluorescence was used to detect NF-κB p65 nuclear translocation. TNF-α significantly induced inflammation of MOVAS cells with expression of inflammatory factors VCAM-1, ICAM-1, MCP-1, IL-1β and IL-6 (P＜0.05). THP-1 cells adhesion was significantly increased (P＜0.001). However, quercetin significantly reduced the expression of the above inflammatory factors and THP-1 cells adhesion (P＜0.05).Quercetin significantly down-regulated phosphorylation (P＜0.01) and nuclear translocation levels of NF-κB p65 subunit induced by TNF-α in MOVAS cells as compared to the control group. Conclusions Quercetin potentially plays a beneficial role in Kawasaki disease by inhibiting the activation of the NF-κB signaling pathway to ameliorate TNF-α-induced inflammation of vascular smooth muscle cells.

Key words: vascular smooth muscle cell, quercetin, TNF-α, inflammation, Kawasaki disease