Correlation of membrane lipid peroxidation with oxidation of hemoglobin variants: Possibly related to the rates of hemin release
Correlation of membrane lipid peroxidation with oxidation of hemoglobin variants: Possibly related to the rates of hemin release
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DOI：
10.1016/0891-5849(96)00035-4
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发表时间：
1996-01-01
影响因子：
7.4
通讯作者：
Liu, TZ
中科院分区：
文献类型：
--
作者：
Chiu, DTY;VanDenBerg, J;Liu, TZ
本实验旨在阐明血红蛋白（Hb）催化人红细胞（RBC）脂质过氧化反应的生化机制。使用改良的朗缪尔槽脂质单层技术，我们发现氧化的Hb诱导脂质单层表面压力增加，表明氧化的Hb容易将其血红素部分释放到脂质单层中。为了证实我们的解释，即氧化的Hb容易释放其血红素部分，我们监测Hb氧化后Hb色氨酸的荧光。我们发现，在加入H2O2后，在我们的单层系统的水相中的Hb荧光增加。荧光的增加应反映血红素离开球蛋白，由于血红素部分的荧光猝灭效应降低。血红蛋白氧化引起的脂质单层表面压力增加速率因血红蛋白而异，其顺序为血红蛋白E > F > S > A。各种血红蛋白的能力，影响红细胞膜脂质过氧化反应，由parinaric酸氧化技术监测，遵循相同的顺序。此外，氯化血红素是一个更有效的催化剂，在红细胞膜脂质过氧化反应比非血红素离子。
Experiments were performed to delineate the biochemical mechanism of hemoglobin (Hb)-catalyzed lipid peroxidation in human red blood cells (RBCs). Using a modified Langmuir trough lipid monolayer technique, we found that oxidized Hb induced an increase in lipid monolayer surface pressure, suggesting that oxidized Hb readily releases its heme moiety into the lipid monolayer, To confirm our interpretation that oxidized Hb readily releases its heme moiety, we monitored the fluorescence of Hb tryptophan upon oxidation of Hb. We found an increase in Hb fluorescence in the aqueous phase of our our monolayer system after the addition of H2O2. The increase in fluorescence should reflect the departure of heme from globin due to a decrease in fluorescent quenching effect by the heme moiety. The rate of increase in Lipid monolayer surface pressure upon Hb oxidation differed from Hb to Hb with an order of Hb E > F > S > A. The ability of various Hbs to affect lipid peroxidation in the RBC membrane, as monitored by the parinaric acid oxidation technique,followed this same order. In addition, hemin was shown to be a more potent catalyst of lipid peroxidation in RBC membrane than nonheme irons.