Figure 1.

Eugenol strongly inhibits superoxide production by fMLF-stimulated human PMN. Human PMN (10⁶/ml) were incubated in the presence or absence of increasing concentrations of EUG for 30 min at 37 °C, then stimulated with fMLF (10⁻⁶ M) or with PMA (100 ng/mL). Superoxide anion production was measured by cytochrome c reduction assay at 550 nm. (A,C) Kinetics of cytochrome c reduction in the presence of increasing concentrations of EUG by fMLF- and PMA-stimulated PMN, respectively. (B,D) The initial velocity of the reaction from several experiments was expressed as percentage of control (PMN stimulated by fMLF or PMA). Data are expressed as mean ± SEM of 3 experiments: p < 0.005 as compared to control (EUG untreated cells; 100%). R: Resting cells.