Fig. 6.

TLR4 siRNA attenuates ox-HDL-induced oxidative stress and CHOP-mediated macrophage apoptosis. RAW264.7 cells were transfected with siRNA directed against TLR4 and then stimulated with ox-HDL (100 mg/l) for 24 h. A: Cell apoptosis was measured by flow cytometry. B: The protein levels of TLR4 and CHOP were determined by Western blot. C: NADPH oxidase activity was determined by cytochrome C chromometry. D: Intracellular ROS levels were measured by DCF analysis using a flow cytometer. E, F: MDA content and SOD activity were determined using commercial kits. Data are expressed as the mean ± SD of at least three independent experiments. Con, control. *P < 0.05; **P < 0.01 versus control group; ^#P < 0.05; ^##P < 0.01 versus ox-HDL treatment.