(A) The chemical structure of 4'-HW. (B) Cytotoxicity in RAW 264.7 macrophages treated with 4'-HW (0.5, 1.5 and 15 μM) for 24 h. (C, D, E, F) Cells were treated with 0.5, 5 and 15 μM 4'-HW for 1h prior to the addition of LPS (100 ng/mL) for an 24 h incubation. NO and PGE2 levels were determined with Griess regent and a commercial kit, respectively. The protein level of iNOS and COX-2 was determined by Western blot analysis using specific antibodies. The immune-reactive bands were quantified using the NIH Image J software. (G and H) Cells were pretreated with 4'-HW for 1 h prior to the addition of LPS (100 ng/mL), and then cells were further incubated for 4 h. The mRNA levels of iNOS and COX-2 were determined by quantitative real-time PCR. The data shown represent the mean ± SD of three independent experiments. #p<0.05 vs the control group; *p<0.05 vs the LPS-treated group.