Portulacerebroside A induces apoptosis via activation of the mitochondrial death pathway in human liver cancer HCCLM3 cells

Portulacerebroside A (PCA) is a novel cerebroside compound isolated from Portulaca oleracea L. The present results showed that PCA significantly inhibited cell viability time-and dose-dependently, elicited chromatin aggregation and fragmented nuclei, and enhanced the percentage of apoptotic cells. Furthermore PCA remarkably increased the protein phosphorylation of p38 MAPK and JNK, disrupted mitochondrial membrane penetrability, and triggered the release of mitochondrial cytochrome c and AIF to cytosol. Treatment with PCA also evidently activated caspase-9 and caspase-3 but not caspase-8. These results suggest that PCA-induced apoptosis is associated with activation of the p38 MAPK-and JNK-triggered mitochondrial death pathway. PCA possibly has the high potential for clinical applications in treating liver cancer and improving cancer chemotherapy. (C) 2013 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.