BUFALIN INHIBITS ENDOTHELIAL-CELL PROLIFERATION AND ANGIOGENESIS IN-VITRO

We have investigated the effects of bufalin, one of the prominent comp onents in Chinese toad venom, on proliferation of bovine aortic endoth elial (BAE) cells and tube formation in three-dimensional type I colla gen matrix. In the present study, bufalin potently inhibited the forma tion of capillary-like tubular networks in a dose-dependent manner. Bu falin also inhibited the proliferation of BAE cells at the same concen tration (5 nM) that the tube formation was inhibited. As a potent inhi bitor of endothelial cell proliferation, bufalin specifically prevente d the entry of BAE cells into the G0/G1 phase of a cell cycle. These f indings suggest that in vitro angioinhibitory action of bufalin may be induced by the proliferation inhibition of endothelial cells through the arrest at the G2/M phase of a cell cycle.