Enhanced oxidation of bis(3,5-dibromosalicyl) fumarate alpha-alpha cross linked hemoglobin by free radicals generated by xanthine/xanthine oxidase.
The xanthine/xanthine oxidase reaction produces reproducible amounts of oxygen-derived free radicals that oxidize human oxyhemoglobin (Hb). We monitored the kinetics of the oxidation of stripped Hb (sHb), purified HbA0 and alpha-alpha cross-linked Hb (HbXL99 alpha) at [Hb] in the 5 to 150 microM (heme) range. For increasing [Hb], the oxidation halftime (t1/2) increased for all Hbs, but t1/2 was always less for HbXL99 alpha than for HbA0 and sHb. Such feature was attributed to the lower affinity for O2 of HbXL99 alpha and may represent a serious problem for use of this Hb as blood substitute.
Samaja
M
M
Department of Biomedical Science and Technology, University of Milano, Italy.
Motterlini
R
R
Rovida
E
E
D001241:Aspirin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D003432:Cross-Linking Reagents; D005609:Free Radicals; D006207:Half-Life; D006441:Hemoglobin A / Q000737:chemistry / Q000378:metabolism; D006454:Hemoglobins / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D010084:Oxidation-Reduction; D010108:Oxyhemoglobins / Q000737:chemistry / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism; D019820:Xanthine; D014969:Xanthine Oxidase / Q000378:metabolism; D014970:Xanthines / Q000378:metabolism
D003432:Cross-Linking Reagents; D005609:Free Radicals; D006454:Hemoglobins; D010108:Oxyhemoglobins; D017382:Reactive Oxygen Species; D014970:Xanthines; C053936:hemoglobin XL99alpha; C021630:bis(3,5-dibromosalicyl)fumarate; D019820:Xanthine; C028881:hemoglobin A(0); D006441:Hemoglobin A; D014969:Xanthine Oxidase; D001241:Aspirin