Involvement of ERK1/2 and p38 MAPK in up-regulation of 14-3-3 protein induced by hydrogen peroxide preconditioning in PC12 cells.
OBJECTIVE
To investigate the protective effects of hydrogen peroxide preconditioning (HPP) on the pheochromocytoma (PC12) cells treated with 1-methyl-4-phenylpyridinium (MPP(+)) and to explore the potential mechanisms.


METHODS
The viability and apoptosis of PC12 cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and 4',6'-diamidino-2-phenylindole (DAPI) staining, respectively. The expressions of 14-3-3 protein and phosphorylated p38 mitogen-activated protein kinase (MAPK) were determined by Western blot. Enzyme-linked immunosorbent assay (ELISA) was used to measure the activity of extracellular signal-regulated protein kinase 1/2 (ERK1/2).


RESULTS
The cell viability decreased and the number of apoptotic cells increased dramatically in MPP(+) group compared with that in Control group. HPP induced a significant increase in cell viability and a marked decrease in population of apoptotic cells of the MPP(+)-treated PC12 cells, accompanied with up-regulation of 14-3-3 protein and increase of ERK1/2 and p38 MAPK activities. The 14-3-3 protein expression was positively correlated with the phosphorylation of ERK1/2. Furthermore, inhibition of the ERK1/2 with PD98059 abolished the 14-3-3 protein up-regulation in PC12 cells induced by HPP.


CONCLUSIONS
HPP protects PC12 cells against MPP(+) toxicity by up-regulating 14-3-3 protein expression through the ERK1/2 and p38 MAPK signaling pathways.
Su
Qing-Jie
QJ
Department of Neurology, the Affiliated Union Hospital of Huazhong University of Science and Techology, Wuhan, China.
Chen
Xiao-Wu
XW
Chen
Zhi-Bin
ZB
Sun
Sheng-Gang
SG
D015655:1-Methyl-4-phenylpyridinium / Q000633:toxicity; D048948:14-3-3 Proteins / Q000096:biosynthesis*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D015153:Blotting, Western; D002470:Cell Survival / Q000187:drug effects; D004797:Enzyme-Linked Immunosorbent Assay; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D016716:PC12 Cells; D010766:Phosphorylation; D051381:Rats; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D015854:Up-Regulation; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
D048948:14-3-3 Proteins; D006861:Hydrogen Peroxide; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D048051:p38 Mitogen-Activated Protein Kinases; D015655:1-Methyl-4-phenylpyridinium