Ginsenosides from the leaves and flower buds of Panax ginseng and their pharmacological effects

摘要

Ginseng, an ancient and famous herbal drug in oriental traditional medicine, has been used as a valuable tonic and for the treatment of various diseases. In medicinal purpose, ginseng root is used more common than aerial parts such as leaves and flower buds although extracts from ginseng aerial parts also contain similar active ingredients having pharmacological functions. This article reviews the purification of thirty four ginsenosides (1-34) from ginseng leaves and flower buds and their pharmacological effects. Ginsenosides are structurally classified into protopanaxadiol (PPD) and protopanaxatriol (PPT) types depending on their aglycones. The anti-oxidant activity of PPD-type ginsenosides like Rb _1, Rd, Rc, and Rh _2 was more active than that of PPT-type ginsenosides. Moreover, the presence of hydroperoxy in ginsenoside molecule was important for the intracellular reactive oxygen species (ROS) scavenging activity of ginsenosides. It became evident that ginsenoside F _1 (8), ginsenoside F _5 (9) and floralginsenoside Ta (21) remarkably inhibited the growth of HL-60 cells via the apoptosis pathway. Ginsenoside I (33) displayed potent inhibitory effect on IL-12 p40 production in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) with IC _(50) of 6.7 μM although floralginsenoside Kc (20) and floralginsenoside J (29) showed moderate effects. Ginsenoside F _1 (8), a major ginsenoside of ginseng leaves, and notoginsenosie R _1 (5) significantly decreased contraction by 35 ± 3.4% and by 53 ± 1.1% at 10 μM, respectively. Floralginsenoside Kc (20), a new ginsenoside from flower-buds, showed positive inotropic effect.