The green tea polyphenol (-)-epigallocatechin gallate attenuates beta-amyloid-induced neurotoxicity in cultured hippocampal neurons.
Previous evidence has indicated that the neuronal toxicity of amyloid beta (betaA) protein is mediated through oxygen free radicals and can be attenuated by antioxidants and free radical scavengers. Recent studies have shown that green tea polyphenols reduced free radical-induced lipid peroxidation. The purpose of this study was to investigate whether (-)-epigallocatechin gallate (EGCG) would prevent or reduce the death of cultured hippocampal neuronal cells exposed to betaA because EGCG has a potent antioxidant property as a green tea polyphenol. Following exposure of the hippocampal neuronal cells to betaA for 48 hours, a marked hippocampal neuronal injuries and increases in malondialdehyde (MDA) level and caspase activity were observed. Co-treatment of cells with EGCG to betaA exposure elevated the cell survival and decreased the levels of MDA and caspase activity. Proapoptotic (p53 and Bax), Bcl-XL and cyclooxygenase (COX) proteins have been implicated in betaA-induced neuronal death. However, in this study the protective effects of EGCG seem to be independent of the regulation of p53, Bax, Bcl-XL and COX proteins. Taken together, the results suggest that EGCG has protective effects against betaA-induced neuronal apoptosis through scavenging reactive oxygen species, which may be beneficial for the prevention of Alzheimer's disease.
Choi
Y T
YT
Department of Psychiatry, Keimyung University School of Medicine, Taegu, Korea.
Jung
C H
CH
Lee
S R
SR
Bae
J H
JH
Baek
W K
WK
Suh
M H
MH
Park
J
J
Park
C W
CW
Suh
S I
SI
D016229:Amyloid beta-Peptides / Q000633:toxicity*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002392:Catechin / Q000031:analogs & derivatives / Q000494:pharmacology*; D002478:Cells, Cultured; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D004305:Dose-Response Relationship, Drug; D004336:Drug Antagonism; D005333:Fetus; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects*; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics; D008315:Malondialdehyde / Q000378:metabolism; D008565:Membrane Proteins; D009474:Neurons / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D018696:Neuroprotective Agents / Q000494:pharmacology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis / Q000235:genetics; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis; D051028:bcl-2-Associated X Protein; D051020:bcl-X Protein
D016229:Amyloid beta-Peptides; D000975:Antioxidants; C494828:Bax protein, rat; C494813:Bcl2l1 protein, rat; D007527:Isoenzymes; D008565:Membrane Proteins; D018696:Neuroprotective Agents; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D016159:Tumor Suppressor Protein p53; D051028:bcl-2-Associated X Protein; D051020:bcl-X Protein; D008315:Malondialdehyde; D002392:Catechin; C045651:epigallocatechin gallate; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases; C496513:Ptgs1 protein, rat; C505410:Casp3 protein, rat; D053148:Caspase 3; D020169:Caspases