Antioxidant activity of albumin-bound bilirubin.
نویسندگان
چکیده
Bilirubin, when bound to human albumin and at concentrations present in normal human plasma, protects albumin-bound linoleic acid from peroxyl radical-induced oxidation in vitro. Initially, albumin-bound bilirubin (Alb-BR) is oxidized at the same rate as peroxyl radicals are formed and biliverdin is produced stoichiometrically as the oxidation product. On an equimolar basis, Alb-BR successfully competes with uric acid for peroxyl radicals but is less efficient in scavenging these radicals than vitamin C. These results show that 1 mol of Alb-BR can scavenge 2 mol of peroxyl radicals and that small amounts of plasma bilirubin are sufficient to prevent oxidation of albumin-bound fatty acids as well as of the protein itself. The data indicate a role for Alb-BR as a physiological antioxidant in plasma and the extravascular space.
منابع مشابه
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ورودعنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 84 16 شماره
صفحات -
تاریخ انتشار 1987