Studies on Reaction Mechanism of Carotenoids and Peroxynitrite In Vivo

过氧亚硝酸盐是体内超氧化物与一氧化氮反应的产物，是一种强氧化剂。已知过氧亚硝酸盐可诱导DNA链断裂，通过硝化和羟基化修饰蛋白质以及LDL中的脂质过氧化。研究了叶黄素、辣椒红素和岩藻黄素对过氧亚硝酸盐的体外反应活性，并对过氧亚硝酸盐清除反应产物进行了分析。从类胡萝卜素与过氧亚硝酸盐反应中分离得到了类硝基胡萝卜素。这些类胡萝卜素抑制过氧亚硝酸盐对酪氨酸的硝化作用。

Peroxynitrite, the reaction product of superoxide and nitric oxide, is a powerful oxidant in vivo. Peroxynitrite is known to induce DNA strand scission, protein modification by nitration and hydroxylation and lipid peroxydation in LDL. The in vitro reactivity of lutein, capsanthin and fucoxanthin toward peroxynitrite was investigated, and the reaction products produced by scavenging with peroxynitrite were analyzed. Nitro-carotenoids were isolated from the reaction of these carotenoids with peroxynitrite. These carotenoids inhibited the nitoration of tyrosin by peroxynitrite.