title: Chemoprotective effect of insulin-like growth factor I against acetaminophen-induced cell death in Chang liver cells via ERK1/2 activation.
abstract: The insulin-like growth factor (IGF) system and type-I IGF receptor (IGF-IR) signaling are involved in protecting against chemotherapeutic drug-induced cell death in human hepatoma cells. Acetaminophen (AAP) hepatotoxicity is the leading cause of liver failure, and the prevention of AAP-induced cell death has been the focus of many studies. We determined whether IGF-I could protect against AAP-induced cell death in Chang liver cells and investigated the protective mechanism. Based on the results of MTS assays, LDH release assays, Hoechst 33342 cell staining, and DNA fragmentation experiments, AAP induced cell death in a dose-dependent manner. According to Western blot analysis, treatment with AAP increased the level of poly(ADP-ribose) polymerase (PARP) fragments in cells compared with that in control cells; however, caspase-3, a critical signaling molecule in apoptosis, was not activated after AAP overdose. Moreover, combined treatment with AAP and IGF-I inhibited PARP cleavage, which was consistent with the ability of IGF-I to restore the level of glutathione (GSH) and cell viability in GSH and MTS assays, respectively. We investigated whether the protective effect of IGF-I against AAP cytotoxicity is related to the extracellular signal-related kinase ERK1/2, which is generally activated by mitogenic and proliferative stimuli such as growth factors. Compared with AAP treatment alone, IGF-I and AAP co-treatment increased ERK1/2 phosphorylation but inhibited PARP cleavage. Thus ERK1/2 activation is instrumental in the protective effect of IGF-I against AAP-induced cell death in Chang liver cells.
authors.affiliation: Faculty of Food Science and Biotechnology, Pukyong National University, 599-1, Daeyeon 3-Dong, Nam-Gu, Busan, Republic of Korea.
authors.forename: Hye-Jung
authors.initials: HJ
authors.lastname: Hwang
authors.forename: Mi-Jin
authors.initials: MJ
authors.lastname: Kwon
authors.forename: Taek-Jeong
authors.initials: TJ
authors.lastname: Nam
mesh_terms: D000082:Acetaminophen / Q000037:antagonists & inhibitors* / Q000633:toxicity*; D018712:Analgesics, Non-Narcotic / Q000037:antagonists & inhibitors* / Q000633:toxicity*; D001562:Benzimidazoles; D015153:Blotting, Western; D016923:Cell Death / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004396:Coloring Agents; D004587:Electrophoresis, Agar Gel; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D005456:Fluorescent Dyes; D005978:Glutathione / Q000378:metabolism; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D008099:Liver / Q000473:pathology*; D020930:MAP Kinase Kinase Kinases / Q000037:antagonists & inhibitors; D019950:Mitogen-Activated Protein Kinase 1 / Q000187:drug effects / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000187:drug effects / Q000378:metabolism*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism; D011419:Propidium
chemical_list: D018712:Analgesics, Non-Narcotic; D001562:Benzimidazoles; D004396:Coloring Agents; D004791:Enzyme Inhibitors; D005419:Flavonoids; D005456:Fluorescent Dyes; D011419:Propidium; D000082:Acetaminophen; D007334:Insulin-Like Growth Factor I; D011065:Poly(ADP-ribose) Polymerases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020930:MAP Kinase Kinase Kinases; D005978:Glutathione; C017807:bisbenzimide ethoxide trihydrochloride; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one