| Abstract | We show that epigallocatechin-3 gallate (EGCG), a major component of green tea, stimulates phospholipase D (PLD) activity in U87 human astroglioma cells. EGCG-induced PLD activation was abolished by the phospholipase C (PLC) inhibitor and a lipase inactive PLC-gamma1 mutant, which is dependent on intracellular or extracellular Ca(2+), with the possible involvement of Ca(2+)/calmodulin-dependent protein kinase II (CaM kinase II). EGCG induced translocation of PLC-gamma1 from the cytosol to the membrane and PLC-gamma1 interaction with PLD1. EGCG regulates the activity of PLD by modulating the redox state of the cells, and antioxidants reverse this effect. Moreover, EGCG-induced PLD activation was reduced by PKC inhibitors or down-regulation of PKC. Taken together, these results show that, in human astroglioma cells, EGCG regulates PLD activity via a signaling pathway involving changes in the redox state that stimulates a PLC-gamma1 [Ins(1,4,5)P(3)-Ca(2+)]-CaM kinase II-PLD pathway and a PLC-gamma1 (diacylglycerol)-PKC-PLD pathway. |
| Authors | Shi Yeon Kim, Bong-Hyun Ahn, Joonmo Kim, Yoe-Sik Bae, Jong-Young Kwak, Gyesik Min, Taeg Kyu Kwon, Jong-Soo Chang, Young Han Lee, Shin-Hee Yoon, Do Sik Min
(Affiliation: Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul, Korea.)
|
| Journal | European journal of biochemistry / FEBS
(Eur J Biochem)
Vol. 271
Issue 17
Pg. 3470-80
(Sep 2004)
ISSN: 0014-2956 Germany |
| PMID | 15317582
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
|
| Chemical References |
- Antineoplastic Agents
- Antioxidants
- Enzyme Inhibitors
- Reactive Oxygen Species
- Tea
- Catechin
- Calcium
- epigallocatechin gallate
- Protein Kinase C
- Calcium-Calmodulin-Dependent Protein Kinase Type 2
- Calcium-Calmodulin-Dependent Protein Kinases
- Type C Phospholipases
- Phospholipase C gamma
- Phospholipase D
- phospholipase D1
|
| Topics |
- Antineoplastic Agents
(metabolism)
- Antioxidants
(metabolism)
- Astrocytoma
(metabolism)
- Brain Neoplasms
(metabolism)
- Calcium
(metabolism)
- Calcium-Calmodulin-Dependent Protein Kinase Type 2
- Calcium-Calmodulin-Dependent Protein Kinases
(metabolism)
- Catechin
(analogs & derivatives, metabolism)
- Cell Line, Tumor
- Enzyme Activation
- Enzyme Inhibitors
(metabolism)
- Humans
- Oxidation-Reduction
- Phospholipase C gamma
- Phospholipase D
(metabolism)
- Protein Kinase C
(metabolism)
- Reactive Oxygen Species
(metabolism)
- Tea
(chemistry)
- Type C Phospholipases
(metabolism)
|
