Ginsenoside-Rh2-induced mitochondrial depolarization and apoptosis are associated with reactive oxygen species- and Ca2+-mediated c-Jun NH2-terminal kinase 1 activation in HeLa cells.
We show here that Ca(2+) and reactive oxygen species (ROS) are involved in the up-regulation of c-Jun NH(2)-terminal kinase 1 (JNK1) activity during apoptosis induced by ginsenoside Rh2 (G-Rh2) in HeLa, MCF10A-ras, and MCF7 cells. Addition of antioxidants such as N-acetyl-l-cysteine or catalase attenuates G-Rh2-induced ROS generation, JNK1 activation, and apoptosis. The overexpression of catalase down-regulates caspase-3 and JNK1 activities. G-Rh2 treatment of cells results in mitochondrial depolarization, second mitochondrial activator of caspase release, and translocation of Bax into the mitochondria, and these events are inhibited by antioxidants. Ca(2+) is also involved in mitochondrial depolarization during G-Rh2-induced apoptosis. These results suggest that ROS and Ca(2+) are important signaling intermediates leading to stress-activated protein kinase/extracellular signal-regulated kinase kinase 1/JNK1 activation and depolarization of the mitochondrial membrane potential in G-Rh2-induced apoptosis.
Ham
Young-Mi
YM
Cell Signal Transduction Laboratory, School of Life Sciences and Biotechnology, Korea University, Seoul, Korea.
Lim
Jin-Hee
JH
Na
Hye-Kyung
HK
Choi
Joon-Seok
JS
Park
Byoung-Duck
BD
Yim
Hyungshin
H
Lee
Seung-Ki
SK
D000975:Antioxidants / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D051017:Apoptosis Regulatory Proteins; D015153:Blotting, Western; D002118:Calcium / Q000502:physiology; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D053938:DNA Fragmentation / Q000187:drug effects; D005434:Flow Cytometry; D036145:Ginsenosides / Q000494:pharmacology*; D006367:HeLa Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism*; D008564:Membrane Potentials / Q000187:drug effects; D018613:Microscopy, Confocal; D008928:Mitochondria / Q000187:drug effects*; D024101:Mitochondrial Proteins / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D013347:Subcellular Fractions / Q000187:drug effects / Q000201:enzymology; D014178:Translocation, Genetic / Q000187:drug effects; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism
D000975:Antioxidants; D051017:Apoptosis Regulatory Proteins; C412403:DIABLO protein, human; D036145:Ginsenosides; D047908:Intracellular Signaling Peptides and Proteins; D024101:Mitochondrial Proteins; D017382:Reactive Oxygen Species; D051028:bcl-2-Associated X Protein; C055305:ginsenoside Rh2; D048031:JNK Mitogen-Activated Protein Kinases; D053148:Caspase 3; D002118:Calcium