FIGURE 4.

KLA alters the amount of sphingoid bases and sphingoid base phosphates. RAW264.7 cells were incubated with vehicle control (PBS) or KLA (100 ng/ml). Following treatment, cells were harvested at the indicated time points for lipid extraction and analysis by LC ESI-MS/MS. A, amounts of sphingoid bases, sphinganine and sphingosine. Data represent the means (n = 9). B, amounts of sphingoid base phosphates, sphinganine 1-phosphate and sphingosine 1-phosphate. Data represent the means ± S.E. (n = 9); *, p ≤ 0.05; **, p ≤ 0.01; ***, p ≤ 0.005; ****, p ≤ 0.001.