New Hydroxycinnamic Acid Esters as Novel 5-Lipoxygenase Inhibitors That Affect Leukotriene Biosynthesis

Figure 4

The impact of test compounds on the liberation of arachidonic acid in stimulated PMNL. Human PMNL were incubated with test compounds (1 μM) or their diluent (control, DMSO 0.5%) for 5 min. Stimulation was then initiated with the addition of 1 μM thapsigargin, followed by an incubation at 37°C for 5 min. The reactions were stopped with the addition of two volumes of cold MeOH and 300 ng of arachidonic acid-d₈, then samples were stored overnight at −20°C. Free arachidonic acid was first extracted on octadecyl columns, then pentafluorobenzylesters of arachidonic acid were prepared and samples were measured on GC-MS. Spontaneous release of AA was also measured in absence of thapsigargin (nonactivated, NA). Different from control as determined by one-way ANOVA with Dunnett’s multiple comparison test (). Data are expressed as means ± SEM of at least 3 independent experiments.