title: Pterin-6-aldehyde, an inhibitor of xanthine oxidase, has superoxide anion radical scavenging activity.
abstract: Superoxide anion radical (O2.-) scavenging activity of neopterin (NP) and its photodegraded products was studied. NP did not affect O2.- release in hypoxanthine/xanthine oxidase (HPX/XOD) reaction system, but pterin-6-aldehyde (P6A), one of photodegraded products of NP, suppressed it. The identification of P6A was successful by confirming inhibiting property of xanthine oxidase. In neutrophil/phorbol myristate acetate reaction system, NP did not affect the O2.- release but P6A suppressed it. The suppression by P6A was not associated with oxygen uptake, which indicated that P6A did not inhibit the generation of O2.- but directly scavenged it. These findings suggest that P6A has ameliorating effects on ischemic-reperfusion injury in which O2.-, which is generated both in HPX/XOD reaction and in activated neutrophil, is one of the major substances to damage the tissues.
authors.affiliation: Department of Anesthesia, Kyoto University Hospital, Sakyo-ku, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Watanabe
authors.forename: T
authors.initials: T
authors.lastname: Arai
authors.forename: H
authors.initials: H
authors.lastname: Mori
authors.forename: S
authors.initials: S
authors.lastname: Nakao
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: K
authors.initials: K
authors.lastname: Tajima
authors.forename: K
authors.initials: K
authors.lastname: Makino
authors.forename: K
authors.initials: K
authors.lastname: Mori
mesh_terms: D001708:Biopterins / Q000031:analogs & derivatives / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D016166:Free Radical Scavengers / Q000494:pharmacology*; D005609:Free Radicals; D006801:Humans; D066298:In Vitro Techniques; D009682:Magnetic Resonance Spectroscopy; D019798:Neopterin; D011621:Pteridines / Q000494:pharmacology*; D011622:Pterins; D013481:Superoxides / Q000378:metabolism*; D014969:Xanthine Oxidase / Q000037:antagonists & inhibitors*
chemical_list: D016166:Free Radical Scavengers; D005609:Free Radicals; D011621:Pteridines; D011622:Pterins; D013481:Superoxides; D001708:Biopterins; D019798:Neopterin; C005926:2-amino-4-hydroxy-6-formylpteridine; D014969:Xanthine Oxidase