ANTIOXIDANT ACTIVITY OF IRON-AMINO ACID-CHELATOR COMPLEXES

与衰老和年龄相关疾病相关的生物分子的氧化损伤是抗氧化剂和促氧化剂活性的复杂功能。通过氨基酸、螯合剂和过渡金属离子的相互作用形成的三元复合物已显示出抗氧化剂（过氧化氢酶样）活性，并在暴露于氧化应激时保护培养的细胞免受损伤。在努力了解参与这种复合物的抗氧化活性的化学机制，我们已经利用了独特的光谱特性的亚铁，氨基酸和铁螯合剂，ferrozine之间形成的复合物。当亚铁加入到含有亚铁嗪和氨基酸的反应混合物中时，形成的主要产物是由两当量的亚铁嗪、两当量的氨基酸和一当量的铁组成的蓝色络合物。根据三种反应物的相对浓度，蓝色络合物可能经历（i）氧气的缓慢氧化或过氧化氢的快速（几乎瞬时）氧化，形成三价铁和其他无色的尚未鉴定的产物，或（ii）可能与另一分子的亚铁嗪反应，再生氨基酸，形成三当量亚铁嗪和一当量亚铁的紫色络合物。- 抗氧化剂，铁-氨基酸复合物，亚铁嗪

Oxidative damage of biomolecules associated with aging and age-related diseases is a complex function of antioxidant and prooxidant activities. Ternary complexes formed by the interaction of amino acids, chelating agents, and transition metal ions have been shown to exhibit antioxidant (catalase-like) activity and to protect cultured cells from damage upon exposure to oxidative stress. In an effort to understand the chemical mechanisms involved in the antioxidant activity of such complexes, we have taken advantage of the unique spectral characteristics of the complexes formed between ferrous iron, amino acids, and the iron chelator, ferrozine. When ferrous iron is added to reaction mixtures containing ferrozine and an amino acid, the primary product formed is a blue complex comprised of two equivalents of ferrozine, two equivalents of amino acid, and one equivalent of iron. Depending upon the relative concentrations of the three reactants, the blue complex may either undergo (i) slow oxidation by oxygen or rapid (almost instantaneous) oxidation by hydrogen peroxide to form ferric iron and other colorless as yet unidentified products, or (ii) may react with another molecule of ferrozine to regenerate the amino acid and form a purple complex of three equivalents of ferrozine and one equivalent of ferrous iron. - antioxidants, iron-amino acid complex, ferrozine