title: Nitric oxide inactivates glyoxalase I in cooperation with glutathione.
abstract: We previously found that glyoxalase I (Glo I) is inactivated upon exposure of human endothelial cells to extracellular nitric oxide (NO), and this event correlates with an increase in its pI on two-dimensional gels. In this study, we demonstrate that NO can modulate Glo I activity in cooperation with cellular glutathione (GSH). Severe depletion of intracellular GSH prevents the inactivation of Glo I in response to NO, although such depletion enhances the inactivation of glyceraldehyde-3-phosphate dehydrogenase (G3PDH), a well-known enzyme susceptible to NO-induced oxidation. S-Nitrosoglutathione (GSNO), an adduct of GSH and NO, lowers the activity of purified human Glo I, while S-nitrosocysteine (CysNO) inactivates the enzyme only in the presence of GSH. This indicates that a dysfunction in Glo I would require the formation of GSNO in situ. Competitive inhibitors of Glo I, S-(4-bromobenzyl)glutathione and its membrane-permeating form, completely abolish the NO action in vitro and inside cells, respectively. Taken together, these results reveal that Glo I can interact directly with GSNO, and that the interaction converts Glo I into an inactive form. Moreover, the data suggest that the substrate recognition site of Glo I might be involved in the interaction with GSNO.
authors.affiliation: School of Pharmaceutical Sciences, Kitasato University, Tokyo, 108-8641, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Mitsumoto
authors.forename: K R
authors.initials: KR
authors.lastname: Kim
authors.forename: G
authors.initials: G
authors.lastname: Oshima
authors.forename: M
authors.initials: M
authors.lastname: Kunimoto
authors.forename: K
authors.initials: K
authors.lastname: Okawa
authors.forename: A
authors.initials: A
authors.lastname: Iwamatsu
authors.forename: Y
authors.initials: Y
authors.lastname: Nakagawa
mesh_terms: D002460:Cell Line; D002463:Cell Membrane Permeability; D003545:Cysteine / Q000031:analogs & derivatives / Q000494:pharmacology; D015180:Electrophoresis, Gel, Two-Dimensional; D004727:Endothelium / Q000166:cytology / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D004912:Erythrocytes / Q000201:enzymology; D005978:Glutathione / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology*; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000037:antagonists & inhibitors / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D007791:Lactoylglutathione Lyase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism / Q000494:pharmacology*; D009603:Nitroso Compounds / Q000494:pharmacology; D026422:S-Nitrosoglutathione; D026403:S-Nitrosothiols
chemical_list: D009603:Nitroso Compounds; D026403:S-Nitrosothiols; C020233:S-(4-bromobenzyl)glutathione; D009569:Nitric Oxide; D026422:S-Nitrosoglutathione; C021315:S-nitrosocysteine; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D007791:Lactoylglutathione Lyase; D005978:Glutathione; D003545:Cysteine