title: H(2)O(2) mediates oxidative stress-induced epidermal growth factor receptor phosphorylation.
abstract: We used a well-established thiol-alkylating agent, N-ethylmaleimide (NEM), to oxidatively stress human keratinocytes. Time course studies revealed that NEM rapidly depleted keratinocytes of reduced glutathione (GSH), which was followed by rapidly increasing levels of intracellular reactive oxygen species (ROS) and subsequently by phosphorylation of epidermal growth factor receptor (EGFR). Pretreatment with antioxidants or enhanced catalase activity in keratinocytes inhibited ROS/H(2)O(2) accumulation and EGFR phosphorylation, demonstrating that H(2)O(2) production is a mediator required for EGFR phosphorylation. Collectively, these results suggest a sequence of events leading to EGFR phosphorylation which is likely shared by oxidative stress-inducing agents, namely: (1) GSH depletion; (2) H(2)O(2) accumulation; and (3) EGFR phosphorylation. We propose that depletion of GSH and accumulation of H(2)O(2) are upstream events and critical mediators required for ligand-independent phosphorylation of growth factor receptors in response to oxidative stress.
authors.affiliation: Department of Dermatology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: A
authors.initials: A
authors.lastname: Meves
authors.forename: S N
authors.initials: SN
authors.lastname: Stock
authors.forename: A
authors.initials: A
authors.lastname: Beyerle
authors.forename: M R
authors.initials: MR
authors.lastname: Pittelkow
authors.forename: D
authors.initials: D
authors.lastname: Peus
mesh_terms: D001205:Ascorbic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D002374:Catalase / Q000378:metabolism; D002478:Cells, Cultured; D018274:Electroporation; D066246:ErbB Receptors / Q000378:metabolism*; D005033:Ethylmaleimide / Q000633:toxicity*; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism*; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D018384:Oxidative Stress; D010766:Phosphorylation; D011435:Propyl Gallate / Q000494:pharmacology; D017382:Reactive Oxygen Species; D014443:Tyrosine / Q000378:metabolism; D014466:Ultraviolet Rays
chemical_list: D017382:Reactive Oxygen Species; D014443:Tyrosine; D011435:Propyl Gallate; D006861:Hydrogen Peroxide; D002374:Catalase; D066246:ErbB Receptors; D005978:Glutathione; D005033:Ethylmaleimide; D001205:Ascorbic Acid; C031226:6-O-palmitoylascorbic acid