title: A novel prolyl hydroxylase inhibitor protects against cell death after hypoxia.
abstract: Hypoxia-inducible factor 1 (HIF-1) is regulated by the oxygen-dependent hydroxylation of proline residues by prolyl hydroxylases (PHDs). We recently developed a novel PHD inhibitor, TM6008, that suppresses the activity of PHDs, inducing continuous HIF-1α activation. In this study, we investigated how TM6008 affects cell survival after hypoxic conditions capable of inducing HIF-1α expression and how TM6008 regulates PHDs and genes downstream of HIF-1α. After SHSY-5Y cells had been subjected to hypoxia, TM6008 was added to the cell culture medium under normoxic conditions. Apoptotic cell death was significantly augmented just after the hypoxic conditions, compared with cell death under normoxic conditions. Notably, when TM6008 was added to the media after the cells had been subjected to hypoxia, the expression level of HIF-1α increased and the number of cell deaths decreased, compared with the results for cells cultured in media without TM6008 after hypoxia, during the 7-day incubation period under normoxic conditions. Moreover, the protein expression levels of heme oxygenase 1, erythropoietin, and glucose transporter-3, which were genes downstream of HIF-1α, were elevated in media to which TM6008 had been added, compared with media without TM6008, during the 7-day incubation period under normoxic conditions. However, the protein expression levels of PHD2 and p53 which suppressed cell proliferation were suppressed in the media to which TM6008 had been added. Thus, TM6008, which suppresses the protein expressions of PHD2 and p53, might play an important role in cell survival after hypoxic conditions, with possible applications as a new compound for treatment after ischemic stroke.
authors.affiliation: Department of Neurology, Tokai University School of Medicine, 143 Shimo-Kasuya, Isehara, Kanagawa, 259-1193, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Kontani
authors.forename: Eiichiro
authors.initials: E
authors.lastname: Nagata
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Uesugi
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Moriya
authors.forename: Natsuko
authors.initials: N
authors.lastname: Fujii
authors.forename: Toshio
authors.initials: T
authors.lastname: Miyata
authors.forename: Shunya
authors.initials: S
authors.lastname: Takizawa
mesh_terms: D015153:Blotting, Western; D016923:Cell Death / Q000187:drug effects*; D015687:Cell Hypoxia; D002460:Cell Line; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism; D064800:Prolyl-Hydroxylase Inhibitors / Q000494:pharmacology*; D060888:Real-Time Polymerase Chain Reaction
chemical_list: C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D064800:Prolyl-Hydroxylase Inhibitors