Fig 3.

EP prevents TNF transcription and synthesis. (a) To analyze the mechanism of EP on LPS-induced TNF release, RAW264.7 macrophage cultures were stimulated with 50 or 100 ng/ml LPS for 20 h, with or without the addition of EP in the concentrations indicated. Note that the concentration of EP that inhibited 50% of the TNF response (EP EC₅₀) from macrophage cultures was 3.4 mM, a clinically achievable concentration. The inhibitory effect of EP on TNF release was significant at all concentrations tested (P < 0.05), as determined by Student's t test. (b) EP prevents TNF transcription, as analyzed by ribonuclease protection assay (RPA III; Ambion, Austin, TX). EP prevented LPS-induced transcription of TNF in a concentration-dependent fashion.