Inhibitory effects of ginsenosides from the root of Panax ginseng on stimulus-induced superoxide generation, tyrosyl or Serine/Threonine phosphorylation, and translocation of cytosolic compounds to plasma membrane in human Neutrophils

The effects of five ginsenosides (G-Rh2(,) -Rd, -Rb-1, -Rb-2, -Rh-1) isolated from the root of Panaxgingseng on stimulus-induced superoxide generation in human neutrophils were evaluated by measuring the reduction of ferricytochrome c. The tyrosyl or serine/threonine phosphorylation of neutrophil proteins and translocation of P47(phox), p67(Phox), and Rac to the plasma membrane were detected using specific monoclonal antibodies. G-Rh2 significantly suppressed superoxide generation induced by Nformylmethionyl-leucylphenylaianine (fMLP), phorbol 12-myristate 13-acetate (PMA), and arachiclonic acid (AA) in a concentration-dependent manner. G-Rh-1 showed a comparably lower suppression on fMLP-induced superoxide generation. G-Rd, -Rb-1, and -Rb-2 also suppressed AA-incluced superoxide generation in high concentrations. G-Rd and G-Rb-1, showed no effect on fMLP- and PMA-induced superoxide generation. FMLP-, PMA-, and AA-induced tyrosyl or serine/threonine phosphorylation and translocation of P47(phox), p67(phox), and Rac to the plasma membrane were in parallel with the suppression of the stimulus-induced superoxide generation.