Panaxatriol (PT)

Panaxatriol is an organic coumpound characterizing a group of ginsenosides. It is a dammarane-type tetracyclic triterpene sapogenin found in ginseng (Panax ginseng) and in notoginseng (Panax pseudoginseng). It is formed by the dehydration of protopanaxatriol. Because of the similarity of chemical structure between PD, PT and dexamethasone (Dexa), a synthetic glucocorticoid, we investigated whether the down-regulation of MMP-9 by PD and PT were mediated by the nuclear translocation of glucocorticoid receptor (GR). Increased GR in the nucleus of HT1080 human fibrosarcoma cells treated by PD and PT was detected by immunocytochemistry. Western blot and gel retardation assays confirmed the increase of GR in the nucleus after treatment with PD and PT. These results suggest that GR-induced down-regulation of MMP-9 by PD and PT contributes to reduce the invasive capacity of HT1080 cells.