Anti-platelet effects of chalcones from Angelica keiskei Koidzumi (Ashitaba) in vivo.

Angelica keiskei Koidzumi (Ashitaba) is a traditional folk medicine that is also regarded in Japan as a health food with potential antithrombotic properties. The ability of the major chalcones, xanthoangelol (XA) and 4-hydroxyderricin (4-HD) extracted from Ashitaba roots to inhibit platelet aggregation activity in vitro was recently determined. However, the anti-platelet activities of Ashitaba chalcones in vivo have remained unclear. The present study examines the anti-platelet effects of Ashitaba exudate and its constituent chalcones using mouse tail-bleeding models that reflect platelet aggregation in vivo. Ashitaba exudate and the major chalcone subtype XA, suppressed the lipopolysaccharide (LPS)-induced shortening of mouse tail bleeding. However, trace amounts of other Ashitaba chalcone subtypes including xanthoangelols B (XB), D (XD), E (XE) and F (XF) did not affect tail bleeding. These results suggest that the major chalcone subtype in Ashitaba, XA, has anti-platelet-activities in vivo.