大豆异黄酮对低密度脂蛋白氧化修饰的抑制作用  

Inhibition effect of soybean isoflavones on the oxidative modification of low-density lipoprotein

作　　者：闫祥华 顾景范[2] 孙存普[2] 刘大星 何传民 

机构地区：[1]济南军区军事医学研究所,济南250014 [2]军事医学科学院

出　　处：《卫生研究》2001年第6期346-349,共4页Journal of Hygiene Research

摘　　要：为探讨大豆异黄酮 (SI)在体外及体内对低密度脂蛋白 (LDL)氧化修饰的作用特点及其与α 生育酚的异同 ,采用密度梯度超速离心法分离制备血清LDL后 ,建立了Cu2 + 诱导LDL氧化修饰反应模型 ,体外向模型中直接加入SI和α 生育酚后 ,通过监测反应体系中硫代巴比妥酸反应物质 (TBARS)和共轭双烯生成量的变化观察它们的作用。体内实验通过先补加SI于高脂饲料喂饲大鼠 ,再测定血中LDL对Cu2 + 诱导氧化的敏感性以反映SI的效果。结果表明 ,体外无论在启动LDL氧化反应前还是反应后加入SI,均显著降低体系中TBARS和共轭双烯的生成 ,并呈现剂量相关关系 ;仅在启动LDL氧化反应前加入α 生育酚显示良好的抑制效果 ,当启动LDL氧化反应后加入α 生育酚则未表现任何防护作用。在大鼠喂饲实验中 ,高脂饲料导致动物LDL对氧化修饰的敏感性增加 ,补加SI对此有明显的拮抗作用。可见 ,在体外SI是与α 生育酚作用有所区别的一类天然抗氧化剂 。In order to investigate the effect of soybean isoflavones(SI) on the oxidative modification to low density lipoprotein(LDL) and to differentiate the effect of SI and α tocopherol, in vitro and in vivo test were conducted. An in vitro model of LDL oxidative modification induced by copper ion was established by monitoring the production of thiobarbituric acid reactive substances (TBARS) and conjugated dienes after SI or α tocopherol was added. The in vivo test was conducted by feeding rats with a high fat diet supplemented with SI and measured the sensitivity of LDL oxidative modification mediated by Cu 2+ in vitro. The results revealed that when SI was added into the in vitro LDL oxidation system, the content of TBARS or conjugated dienes in the system was much reduced with a dose effect relationship, whether lipid oxidation being initiated or not by copper ion at 37℃. In comparison with SI, only a significant inhibiting effect on lipid oxidation while α tocopherol was added before the initiation of oxidation. High fat diet induced a rising of LDL sensitivity of oxidative stress, and adding SI to the high fat diet could counteract the sensitivity of LDL oxidative modification significantly. It is concluded that SI is a valuable natural antioxidant different from α tocopherol in inhibiting LDL oxidative modification both in vitro and inv vivo.

关 键 词：大豆异黄酮 低密度脂蛋白 氧化修饰 抑制作用 

分 类 号：R151.2[医药卫生—营养与食品卫生学] R543.5[医药卫生—公共卫生与预防医学]