Figure 4.

Triptolide potently inhibits the production of pro-inflammatory cytokine proteins in macrophages treated with LPS. RAW264.7 cells (A) and primary peritoneal macrophages (B) were pretreated with indicated doses of triptolide for 30 min followed by stimulation with 100 ng/ml LPS for 6 h. The negative control was only treated with equal volume of vehicle (DMSO). Positive controls were those first treated with vehicle (DMSO) then stimulated with LPS. Upper panels represent the effect of triptolide on TNF-α and IL-6 secretion, which were assayed by ELISA. Results in the graph represent % relative to the mean value of the positive controls. Data were expressed as means ± S.E. from 3 independent experiments. *, p<0.05, compared to the group stimulated with LPS after pretreatment with vehicle. Lower panels demonstrate the effect of triptolide on IL-1βproduction detected by Western blot analysis. Presented are the representative results of at least three experiments.