title: Dinitrosyl iron complexes bind with hemoglobin as markers of oxidative stress.
abstract: Prooxidant and antioxidant properties of nitric oxide (NO) during oxidative stress are mostly dependent on its interaction with reactive oxygen species, Fe ions, and hemoproteins. One form of NO storage and transportation in cells and tissues is dinitrosyl iron complexes (DNIC), which can bind with both low-molecular-weight thiols and proteins, including hemoglobin. It was shown that dinitrosyl iron complexes bound with hemoglobin (Hb-DNIC) were formed in rabbit erythrocytes after bringing low-molecular-weight DNIC with thiosulfate into blood. It was ascertained that Hb-DNIC intercepted free radicals reacting with hemoglobin SH-groups and prevented oxidative modification of this protein caused by hydrogen peroxide. Destruction of Hb-DNIC can take place in the presence of both hydrogen peroxide and tert-butyl hydroperoxide. Hb-DNIC can also be destroyed at the enzymatic generation of superoxide-anion radical in the xanthine-xanthine oxidase system. If aeration in this system was absent, formation of the nitrosyl R-form of hemoglobin could be seen during the process of Hb-DNIC destruction. Study of Hb-DNIC interaction with reactive oxygen metabolites is important for understanding NO and Hb roles in pathological processes that could result from oxidative stress.
authors.affiliation: A. N. Bach Institute of Biochemistry, Russian Academy of Sciences, Moscow, Russia.
authors.forename: Konstantin B
authors.initials: KB
authors.lastname: Shumaev
authors.forename: Olga V
authors.initials: OV
authors.lastname: Kosmachevskaya
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Timoshin
authors.forename: Anatoly F
authors.initials: AF
authors.lastname: Vanin
authors.forename: Alexey F
authors.initials: AF
authors.lastname: Topunov
mesh_terms: D000818:Animals; D004578:Electron Spin Resonance Spectroscopy; D005260:Female; D005609:Free Radicals / Q000378:metabolism; D006454:Hemoglobins / Q000737:chemistry* / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism / Q000494:pharmacology; D007501:Iron / Q000737:chemistry* / Q000378:metabolism*; D009589:Nitrogen Oxides / Q000737:chemistry* / Q000378:metabolism*; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D011485:Protein Binding; D011817:Rabbits; D013113:Spin Labels; D013481:Superoxides / Q000378:metabolism; D020122:tert-Butylhydroperoxide / Q000378:metabolism / Q000494:pharmacology
chemical_list: D005609:Free Radicals; D006454:Hemoglobins; D009589:Nitrogen Oxides; D013113:Spin Labels; D013481:Superoxides; C073661:dinitrosyl iron complex; D020122:tert-Butylhydroperoxide; D006861:Hydrogen Peroxide; D007501:Iron