Flavones from Scutellaria baicalensis Georgi attenuate apoptosis and protein oxidation in neuronal cell lines.
The oxidative modification of proteins plays a major role in a number of human diseases including Alzheimer's disease (AD). Flavones in extracts of Scutellaria baicalensis (SbE) have been reported to have exceptional antioxidant properties. We examined the effects of SbE on neuronal cells exposed to oxidative stress. Neuronal HT-22 cells were exposed to low levels of H(2)O(2) generated from glucose oxidase (GO) under conditions that caused cell death in 24 h. The mechanism of cell death was shown to occur via apoptosis. Flavone extracts (50 microg/ml) protected cells and increased viability to 85+/-5% (P<0.001). The flavones also increased the content of Bcl-2 in the cell, resulted in its phosphorylation, and in contrast decreased the Bax levels. Furthermore, the oxidative-stress-induced protein carbonyl formation was reduced nearly two-fold when cells were pretreated with the flavone extract. Two-dimensional electrophoresis (2-DE) showed that less than 15% of the total visible proteins were oxidized and that the oxidation was specific for certain oxidation-sensitive proteins. These data support the idea that flavones in SbE can attenuate oxidant stress and protect cells from lethal oxidant damage.
Choi
Joungil
J
Molecular Aging Unit, Department of Molecular Biology and Immunology, University of North Texas Health Science Center, 3500 Camp Bowie Blvd., Fort Worth, TX 76107, USA.
Conrad
Craig C
CC
Malakowsky
Christina A
CA
Talent
John M
JM
Yuan
Chun-Su
CS
Gracy
Robert W
RW
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D019610:Cytoprotection / Q000187:drug effects; D004365:Drugs, Chinese Herbal / Q000494:pharmacology; D015180:Electrophoresis, Gel, Two-Dimensional; D005419:Flavonoids / Q000494:pharmacology*; D005949:Glucose Oxidase / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000633:toxicity; D007526:Isoelectric Point; D019686:Lamiaceae / Q000737:chemistry; D051379:Mice; D008970:Molecular Weight; D009474:Neurons / Q000166:cytology / Q000187:drug effects*; D016877:Oxidants / Q000633:toxicity; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D010766:Phosphorylation / Q000187:drug effects; D011506:Proteins / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D051028:bcl-2-Associated X Protein
C494827:Bax protein, mouse; D004365:Drugs, Chinese Herbal; D005419:Flavonoids; D016877:Oxidants; D011506:Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D017382:Reactive Oxygen Species; D051028:bcl-2-Associated X Protein; D006861:Hydrogen Peroxide; D005949:Glucose Oxidase