Antifibrotic activity of triterpenoids from the aerial parts of Euscaphis japonica on hepatic stellate cells.

In the course of screening antifibrotic activity of natural products employing HSC-T6, a rat hepatic stellate cell line, as an in vitro assay system, the methanolic extract of aerial parts of Euscaphis japonica (Tunb.) Kantiz (Staphyleaceae) showed significant inhibitory activity on HSC proliferation. Activity-guided fractionation led to the isolation of four triterpenoids, friedeline (1), glut-5-en-ol (2), pomolic acid (3), and methylrotundate (4). Among the triterpenoids isolated, pomolic acid (3) significantly inhibited the proliferation of HSCs at concentrations 10 and 100 microM.