Rosmarinic acid inhibits angiogenesis and its mechanism of action in vitro.

Rosmarinic acid (RA), a water-soluble polyphenolic compound with anti-oxidative and anti-inflammatory activities, inhibited several important steps of angiogenesis including proliferation, migration, adhesion and tube formation of human umbilical vein endothelial cells (HUVEC) in a concentration-dependent manner. RA also reduced intracellular reactive oxygen species (ROS) level, H2O2-dependent VEGF expression and IL-8 release of endothelial cells. These findings suggested that the anti-angiogenic potential of RA might be related to its anti-oxidative activity, which further resulted in the inhibition of ROS-associated VEGF expression and IL-8 release.