Inhibition of Oxidative Low-density Lipoprotein Induced-tissue Factor Expression in Endothelial cells by Demethylbellidifolin and Its Mechanism

[Objective] To investigate the effect of demethylbellidifolin(DMB),a xanthone compound,on oxidative low-density lipoprotein(ox-LDL)-induced tissue factor(TF)expression in endothelial cells and its underlying mechanism.[Methods] Human umbilical vein endothelial cells(HUVECs)were cultured and treated with ox-LDL(0.2 mg/mL)for 24h to induce TF expression.The activity and mRNA expression of TF were determined by one-stage clotting assay and reverse transcription PCR,respectively.The level of intracellular reactive oxygen species(ROS)was determined by H2DCF,an oxidative sensitive fluorescent indicator.The DNA-binding activity of nuclear factor(NF)-κB in nuclear extracts was analyzed by electrophoretic mobility shift assay(EMSA).[Results] Treatment with ox-LDL could induced TF mRNA expression and increase its activity.The increase in intracellular ROS production and the activation of NF-κB were observed in HUVECs treated with ox-LDL.However,the addition of different concentrations of DMB(1,3 and 10 μmol/L)1h before ox-LDL stimulation could markedly inhibit ox-LDL-induced increases in TF activity and mRNA level in a concentration-dependent manner.Also,the elevation of intracellular ROS production and the activation of NF-κB elicited by ox-LDL were significantly suppressed by pretreatment with DMB.[Conclusion] DMB inhibits ox-LDL-induced TF expression in endothelial cells,and such effects of DMB may be related to inhibiting intracellular ROS production and NF-κB activation.