[Interaction of riboflavin and hemoproteins with organic free radicals and superoxide anions generated in the ultrasound field].
The reduction of ferricytochrome c to the ferro form in aqueous alcohol solutions in air by the action of ultrasound and the complete inhibition of this process in the presence of superoxide dismutase indicate the generation of superoxide anions. Further exposure to the ultrasonic field leads to a reverse process of oxidation of the cytochrome c ferro form to the ferri form by hydrogen peroxides and organic peroxides. The addition of catalase protects the cytochrome c ferro form from oxidation to the ferri form. The oxidized form of riboflavin effectively interacts with organic free radicals and superoxide anions to produce a leuko form, which is easily oxidized by air oxygen or the ferri forms of hemoglobin and cyt c to form riboflavin and hydrogen peroxide or the ferro forms of heme-containing proteins, respectively. The recurrence of redox reactions in the presence of riboflavin, organic free radicals, and O2 and the ferri forms of heme-containing proteins suggests that riboflavin can play a role of an antioxidant in the organism. It is supposed that, due to interaction with superoxide anions, riboflavin stabilizes the NO level in the organism under conditions of increased superoxide anion generation and (or) decreased superoxide dismutase activity. A possible role of riboflavin in the modulation of toxic and signal pathways of nitrogen oxide is discussed.
Stepuro
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II
Institute of Biochemistry, Academy of Sciences of Belarus, bulv. Tarashkevicha 50, Grodno, 230017 Belarus.
Adamchuk
R I
RI
Stepuro
A I
AI
D000388:Air; D000438:Alcohols / Q000737:chemistry*; D003574:Cytochrome c Group / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry; D005296:Ferrous Compounds / Q000737:chemistry; D005609:Free Radicals / Q000737:chemistry; D006454:Hemoglobins / Q000737:chemistry*; D006801:Humans; D007700:Kinetics; D009584:Nitrogen; D010084:Oxidation-Reduction; D012256:Riboflavin / Q000737:chemistry*; D013481:Superoxides / Q000737:chemistry*; D014465:Ultrasonics
D000438:Alcohols; D003574:Cytochrome c Group; D005290:Ferric Compounds; D005296:Ferrous Compounds; D005609:Free Radicals; D006454:Hemoglobins; D013481:Superoxides; D009584:Nitrogen; D012256:Riboflavin