RESUMO
<p><b>OBJECTIVE</b>To study the mechanisms of pseudolaric acid B-induced apoptosis on A375-S2 cells.</p><p><b>METHOD</b>MTT, fluorescence microscope observation, DNA agarose gel electrophoresis and Western blot analysis wereused.</p><p><b>RESULT</b>Pseudolaric acid Binduces A375-S2 cell apoptosis in a time and dose-dependent manner. Apoptotic bodies and DNA ladder were observed in 5 micromol x L(-1) pseudolaric acid B-treated A375-S2 cells for 36 h. The expression of Bcl-2, Bcl-xL and ICAD was reduced time dependently, whereas the expression of Bax was increased.</p><p><b>CONCLUSION</b>The major cause of pseudolaric acid B induced cytotoxicity on A375-S2 cells was apoptosis. Mitochondria proteins and ICAD might be involved in the apoptotic pathways of pseudolaric acid B-treated A375-S2 cells.</p>