Inhibition of vascular endothelial growth factor expression and production by triptolide

Triptolide, the major component of the diterpenoids of the Chinese herb Tripterygium wilfordii Hook f. (Celastraceae), inhibited vascular endothelial growth factor expression and secretion in endothelial cells treated by 12-O-tetradecanoylphorbol 13-acetate dose-dependently. This effect may be one of the mechanisms underlying the therapeutic effects of triptolide on rheumatoid arthritis.