Fig. 5.

DPI attenuates CHOP-mediated macrophage apoptosis induced by ox-HDL. RAW264.7 cells were pretreated with or without 5 µmol/l DPI (NADPH oxidase inhibitor) for 1 h, and then stimulated with ox-HDL (100 mg/l) for 24 h. Cell viability (A) and LDH activity in media (B) were determined by MTT assay and a kit, respectively. C: Cell apoptosis was measured by TUNEL assay. Scale bar = 20 µm. Cells were pretreated with or without DPI (5 µmol/l) for 1 h, followed by stimulation with ox-HDL (100 mg/l) or ox-LDL (100 mg/l) for 24 h. D: NADPH oxidase activity was determined by cytochrome C chromometry. E: Intracellular ROS levels were measured by DCF analysis using a flow cytometer. F, G: MDA content and SOD activity were determined using commercial kits. H, I: Cells were treated as described in A, and then the protein and mRNA levels of GRP78 and CHOP were determined by Western blot and quantitative real-time PCR, respectively. Data are expressed as the mean ± SD of at least three independent experiments. *P < 0.05; **P < 0.01 versus control group; ^#P < 0.05; ^##P < 0.01 versus ox-HDL treatment.