Potentiation of nerve growth factor-mediated nerve fiber production in organ cultures of chicken embryonic ganglia by ginseng saponins: Structure-activity relationship.

Abstract

Potentiation of the nerve growth factor (NGF)-mediated nerve fiber production in organ cultures of chicken embryonic dorsal root ganglia (DRG) and lumbar sympathetic ganglia (SymG) by saponins isolated from Panax ginseng and Panax japonicum and related compounds was studied in order to elucidate the structure-activity relationship. Panax saponins and related compounds so far tested did not promote nerve fiber production, but some 20(S)-protopanaxadiol glycosides having glucose units in their 2 sugar moieties potentiated the effect of NGF. Removal of glucose or introduction of a hydroxy group into the side chain of ginsenoside Rd reduced the activity. Little difference was observed in the potentiation of the NGF effect by the saponins in organ cultures of DRG and SymG.