Saikosaponin D isolated from Bupleurum falcatum inhibits selectin-mediated cell adhesion.

Three saikosaponins were isolated from the MeOH extract of the roots of Bupleurum falcatum L.: saikosaponins B3 (1); B4 (2); and D (3). Of the three, compound 3 inhibited the interaction of selectins (E, L, and P) and THP-1 cells with IC50 values of 1.8, 3.0 and 4.3 µM, respectively. Also, the aglycone structure 4 of compound 3 showed moderate inhibitory activity on L-selectin-mediated cell adhesion. From these results, we suspect that compound 3 isolated from Bupleurum falcatum roots would be a good candidate for therapeutic strategies to treat inflammation.