[Role of oxidized low-density lipoprotein in NF-κB signal pathway].

OBJECTIVE: To explore the effects of oxidized low-density lipoprotein (ox-LDL) on P65, P50, tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6) of human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were randomly divided into several groups as follows: the control group, the ox-LDL stimulated groups (different concentrations: 15, 30, 60, 120 μg/mL ox-LDL stimulation for 24 hours, and 30 μg/mL ox-LDL stimulation for different time periods: 12, 24, 48 hours), and the NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) intervention group (100 μmol/L PDTC pretreatment for 1 h before 30 μg/mL ox-LDL stimulation for 24 hours). Nucleoprotein was extracted to detect P65 and P50 protein expression of NF-κB signaling pathway by Western blotting, and the concentrations of TNF-α and IL-6 in cell supernatants were measured by ELISA. RESULTS: Western blotting showed that the expressions of P65 and P50 increased under the induction of ox-LDL in a time- and concentration-dependent manner, and the differences were statistically significant among groups (P < 0.05), while they were reduced significantly by PDTC intervention (P < 0.05). ELISA showed that the concentrations of TNF-α and IL-6 in the supernatants of HUVECs stimulated by ox-LDL for 24 hours were significantly higher than those in the control group, while they were reduced significantly by PDTC intervention. There were significant statistical differences among the different treated groups (P < 0.05). CONCLUSION: Ox-LDL can enhance the activity of NF-κB signaling pathway in a time- and concentration-dependent manner through increasing the expressions of TNF-α and IL-6.