Premium
Mitochondrial ROS burst as an early sign in sarsasapogenin‐induced apoptosis in HepG2 cells
Author(s) -
Ni Yuan,
Gong Xingguo,
Lu Min,
Chen Hanmin,
Wang Yong
Publication year - 2008
Publication title -
cell biology international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.932
H-Index - 77
eISSN - 1095-8355
pISSN - 1065-6995
DOI - 10.1016/j.cellbi.2007.12.004
Subject(s) - reactive oxygen species , apoptosis , mitochondrion , flow cytometry , glutathione , microbiology and biotechnology , cytochrome c , intracellular , cytosol , biology , depolarization , membrane potential , chemistry , biochemistry , biophysics , enzyme
Sarsasapogenin is a steroidal sapogenin with antitumor properties. To explain the mechanism of its apoptotic effect, mitochondrial activity was assessed via a 3,(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay. Flow cytometry (FCM) was used to estimate the changes in mitochondrial membrane potential (MMP), reactive oxygen species (ROS) generation, and cellular‐reduced glutathione (GSH) level. Laser scanning confocal microscope (LSCM) recorded instantaneous ROS burst after application of sarsasapogenin. Western blotting was used to determine the expression level and intracellular distribution of cytochrome c (cyt c ). It is demonstrated that during apoptosis, ROS burst acted as an early event followed by depolarization of MMP, prolonged ROS generation, and significantly declined GSH level. Cyt c was upregulated and released from mitochondria to cytosol during the process. These findings show that a mitochondrial ROS burst is an early upstream apoptotic signal which may trigger the mitochondrial apoptotic pathway and play a vital role in sarsasapogenin‐induced HepG2 cell apoptosis.