Oxidative stress differentially modulates phosphorylation of ERK, p38 and CREB induced by NGF or EGF in PC12 cells.
This study assessed if oxidative stress induced by treatment of PC12 cells with H2O2 modulated signaling cascades induced by nerve growth factor (NGF) or epidermal growth factor (EGF) because oxidative stress and impaired growth factor function are associated with aging and aging-associated diseases such as Alzheimer's disease. Phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK 1/2) and of p38 kinase was rapidly increased after treatment with NGF, EGF, or H2O2, with NGF causing more prolonged increases than the other agents. Pretreatment with H2O2 did not alter phosphorylation of ERK1/2 induced by either growth factor, but increased the phosphorylation of p38 kinase induced by treatment with NGF or EGF alone. CREB phosphorylation at SER 133 was rapidly increased by treatment with either NGF or EGF. Pretreatment with H2O2 reduced CREB phosphorylation induced by either growth factor. This seemed to be a direct effect because H2O2 also inhibited CREB phosphorylation induced by the adenylyl cyclase stimulator forskolin. These results demonstrate that oxidative stress can differentially modulate growth factor-initiated signaling cascades. Furthermore, because CREB is an evolutionarily preserved protein involved in the formation of long term memory, these results indicate a new target of oxidative stress that may be important in disorders involving impaired memory, such as Alzheimer's disease.
Zhang
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Department of Psychiatry & Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham 35294-0017, USA.
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D000544:Alzheimer Disease / Q000378:metabolism; D000818:Animals; D005576:Colforsin / Q000494:pharmacology; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism*; D004789:Enzyme Activation / Q000187:drug effects; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D020935:MAP Kinase Signaling System / Q000187:drug effects; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D020932:Nerve Growth Factor / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects / Q000201:enzymology*; D016877:Oxidants / Q000494:pharmacology; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology*; D016716:PC12 Cells; D010766:Phosphorylation; D051381:Rats; D048051:p38 Mitogen-Activated Protein Kinases; D018631:ras Proteins / Q000378:metabolism
D017362:Cyclic AMP Response Element-Binding Protein; D016877:Oxidants; D005576:Colforsin; D004815:Epidermal Growth Factor; D020932:Nerve Growth Factor; D006861:Hydrogen Peroxide; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D018631:ras Proteins