FIGURE 6.

TNFα stimulation generates oxidatively truncated phospholipid. A, Az-PC is present in Jurkat cells after TNFα stimulation. Lipids extracted from Jurkat cells after treatment with TNFα (40 ng/ml) for 24 h or a synthetic Az-PC were analyzed by LC/MS/MS using the [M + H]⁺ m/z 661 → m/z 184 transition. B, palmitoyl Az-PC is present after TNFα stimulation. Product ion scans in the negative mode were performed for both synthetic Az-PC standard and the co-eluting peak from TNFα-treated cells. The fragmentation spectrum pattern establishes the presence of the azelaoyl residue from the intramolecularly methylated azelaoyl fragment (m/z 201) in both the standard and co-eluting cellular peak. C, Az-PC increases over time of TNFα stimulation. Jurkat cells were treated with TNFα for the stated times before the cells were lysed, and Az-PC content was determined by mass spectrometry in relation to the synthetic standard. n = 3; *, p < 0.05 from time 0. Error bars, S.E.