Inhibitory effect of ginsenoside on the mediator release in the guinea pig lung mast cells activated by specific antigen-antibody reactions

We reported that some components of ginsenosides decreased mediator release which was evoked by the activation of mast cells caused by specific antigen-antibody reactions. This study aimed to assess the effects of ginsenoside, Rb-1, which belongs to the protopanaxadiol, on the mechanism of mediator release during mast cell activation. Pretreatment of Rb-1 (100 mu g) significantly decreased histamine and leukotriene in a dose-dependent manner during mast cell activation. The PLD activity during mast cell activation decreased in the pretreatment of Rb-1 (300 mu g). The amount of DAG produced by PLC activity decreased because of Rb-1 pretreatment. The amount of mass DAG decreased due to Rb-1 pretreatment during mast cell activation. Rb-1 (300 mu g) pretreatment strongly inhibited the incorporation of the [H-3]methyl moiety into phospholipids. The data suggest that Rb-1, purified from Korean Red Ginseng Radix, inhibits an increase of DAG production during mast cell activation caused by antigen-antibody reactions, which is mediated via phosphatidylcholine-PLD and phosphatidylinositol-PLC systems. This is then followed by the inhibition of histamine releases. Furthermore, Rb-1 reduces the phosphatidylcholine production by inhibiting the methyltransferase I and II, and the reduction of phosphatidylcholine production inhibits leukotriene release. (C) 1998 International Society for Immunopharmacology. Published by Elsevier Science Ltd.