title: Monitoring the Glutathione Redox Reaction in Living Human Cells by Combining Metabolic Labeling with Heteronuclear NMR.
abstract: The glutathione (GSH) redox reaction is critical for defense against cellular reactive oxygen species (ROS). However, direct and real-time monitoring of this reaction in living mammalian cells has been hindered by the lack of a facile method. Herein, we describe a new approach that exploits the GSH biosynthetic pathway and heteronuclear NMR. [U-(13) C]-labeled cysteine was incorporated into GSH in U87 glioblastoma cells, and the oxidation of GSH to GSSG by a ROS-producing agent could be monitored in living cells. Further application of the approach to cells resistant to temozolomide (TMZ), an anti-glioblastoma drug, suggested a possible new resistance mechanism involving neutralization of ROS. This result was corroborated by the observation of up-regulation of glutathione peroxidase 3 (GPx3). This new approach could be easily applied to redox-dependent signaling pathways and drug resistance involving ROS.
authors.affiliation: College of Pharmacy, Natural Product Research Institute, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea.
authors.forename: Xing
authors.initials: X
authors.lastname: Jin
authors.affiliation: College of Pharmacy, Natural Product Research Institute, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea.
authors.forename: Soeun
authors.initials: S
authors.lastname: Kang
authors.affiliation: Department of Pathology, Laboratory of Cancer Research, Hokkaido University Graduate School of Medicine, N15, W7, Kita-ku, Sapporo, 060-8638, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Tanaka
authors.affiliation: College of Pharmacy, Natural Product Research Institute, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Korea. psh@snu.ac.kr.
authors.forename: Sunghyouk
authors.initials: S
authors.lastname: Park
mesh_terms: D053898:Biosynthetic Pathways; D045744:Cell Line, Tumor; D002470:Cell Survival; D003545:Cysteine / Q000032:analysis / Q000378:metabolism; D019008:Drug Resistance, Neoplasm; D005909:Glioblastoma / Q000188:drug therapy / Q000378:metabolism; D005978:Glutathione / Q000032:analysis / Q000378:metabolism*; D006801:Humans; D007553:Isotope Labeling / Q000379:methods; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D005978:Glutathione; D003545:Cysteine
keywords: cancer; drug resistance; glutathione; in-cell NMR; redox chemistry