Growth inhibitory effect of green tea extract in Ehrlich ascites tumor cells involves cytochrome c release and caspase activation.
We reported previously that the mechanism by which Green tea extract (GTE) elicited growth-inhibitory effects in Ehrlich ascites tumor cells involved a decrease in ornithine decarboxylase (ODC) activity and in cell viability. Decrease in ODC activity has been associated with apoptotic cell death and we therefore studied changes in cytochrome c release and caspase activation, which characterize apoptosis. GTE caused a dose- and time-dependent increase in caspase-3-like protease activation, preceded by a release of cytochrome c from the mitochondria. Inhibiting the activation of caspase-3 with acetyl-Asp-Glu-Val-Asp-alpha-aldehyde (caspase inhibitor) caused a reversal in the effect on cell viability.
Kennedy
D O
DO
Department of Food and Nutrition, Faculty of Human Life Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, 558-8585, Osaka, Japan.
Kojima
A
A
Yano
Y
Y
Hasuma
T
T
Otani
S
S
Matsui-Yuasa
I
I
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002286:Carcinoma, Ehrlich Tumor / Q000378:metabolism* / Q000473:pathology*; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism*; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D003574:Cytochrome c Group / Q000378:metabolism*; D004789:Enzyme Activation; D007700:Kinetics; D051379:Mice; D009842:Oligopeptides / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology; D013662:Tea / Q000737:chemistry*
D015853:Cysteine Proteinase Inhibitors; D003574:Cytochrome c Group; D009842:Oligopeptides; D010936:Plant Extracts; D013662:Tea; C108637:aspartyl-glutamyl-valyl-aspartal; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases