Growth inhibition and induction of apoptosis in human cancerous HeLa cells by Maytenus procumbens

The possible biochemical activities of the acetonic/ethanolic extract of the leaves of Maytenus procumbens (L.M.P), and its isolated compounds were investigated in the present study. In cytotoxicity assay, L.M.P showed IC50 of 68.79, 51.22, 78.49, 76.59, and 76.64 mu g/ml on Caco-2, HeLa, HT29, NIH3T3, and T47D cells, respectively. Bioassay guided fractionation led to the isolation and identification of a new triterpene: '30-hydroxy-11 alpha-methoxy-18 beta-olean-12-en-3-one' (HMO) in addition to a known terpenoid: 'asiatic acid' (AA). HMO exhibited the most cytotoxicity against HeLa cells and was further investigated for its ability to induce apoptosis in HeLa cells. HMO induced apoptosis up to 20.41% in HeLa cells versus control group (0.40%). Antioxidant/oxidative properties of L.M.P and HMO were investigated using extracellular (DPPH), and intracellular (ROS) assays. Experimental samples represented a time and concentrationdependent formation of ROS in Hela cells. Generation of ROS seems one of the mechanisms by which HMO induces apoptosis in Hela cells. Conclusion is that the active components in L.M.P might serve as a mediator of the ROS scavenging system and have the potential to act as prooxidant or antioxidant depending on the biological environment of the cells. (C) 2012 Elsevier Ltd. All rights reserved.