【作者】 罗娜；

【导师】 邹伟；

【作者基本信息】 辽宁师范大学 ， 细胞生物学， 2006， 硕士

【摘要】 磷脂酰胆碱（Phosphatidylcholine，PC）也称卵磷脂。它是细胞膜的重要组成成分，起保护层的作用，能重新修复由于自由基攻击生物大分子而产生的膜损伤；它具有胆碱成分，胆碱对脂肪具有亲和力，可使脂肪以磷脂形式由肝脏通过血液输送出去，从而防止脂肪肝的形成；它是提供神经物质乙酰胆碱的前体物质，具有健脑功能；还用于脂质体的研究，以及作为抗癌药物的研究，在食品、医药、化妆品等领域有广阔的应用前景。 肝脏是人体代谢的中心站，含有极其丰富的PC。在哺乳动物肝脏中，除了CDP-胆碱通路（又称Kennedy通路）外，还存在一条特有的PC合成通路，即磷脂酰乙醇胺N-甲基转移酶（phosphatidylethanolamine N-methyltransferase，PEMT）催化磷脂酰乙醇胺（phosphorylethanolamine，PE）甲基化生成PC的通路。研究发现，肝病时合成PC的PEMT活性降低。我们实验室利用基因转染技术过表达PEMT2后，发现大鼠肝癌细胞的生长被显著抑制，并诱发其细胞凋亡。提示，肝脏中的PC可能具有独特的作用。有研究表明，肝细胞损伤时，细胞膜的PC代谢和含量会发生明显的变化。那么，补充外源肝性的PC是否有利于受损伤的肝细胞恢复或减轻肝损伤的程度? CCl₄是目前建立肝细胞实验性损伤模型的常用药物，能成功的复制肝损伤模型。CCl₄可通过P-450酶系统脱卤素后形成CCl₃自由基，后者能从不饱和脂肪酸分子中夺取氢离子，引起脂质过氧化。本研究以CCl₄诱导正常人肝细胞HL7702损伤，复制肝细胞损伤模型，观察了补充肝源PC对肝更多还原

【Abstract】 Phosphatidylcholine, also called Lecithin, is an important constitution of cell membrane, and functions as a protection layer. It can restore cell membrane damaged by free radical. Phosphatidylcholine contains choline, which has affinities to fat. So it can transport fat out of liver by blood in phospholipids, to prevent the formation of fatty liver. Phosphatidylcholine has sanitarian effects on mind, for it provides substances that can form acetylcholine, which is a nerve product. It also be used as liposome and anti-cancer drugs. Furthermore, it has broad application prospects in food, medicine, toiletry and so forth.Liver is the center of metabolism and extremely rich in PC. Except for the CDP-Choline pathway, it also has a special PC synthesis pathway in mammals, in which phosphatidylethanolamine N-methyltransferase catalyzes phosphatidylethanolamine to form PC. It has been reported that the activity of PEMT decreases when pathological changes occur in livers. Our lab transfected hepatoma with PEMT2 overexpression gene, and found that the growth of the cell is remarkably inhibited. Moreover, PEMT2 overexpression could induce apoptosis. It suggests that PC in livers may have unique functions.CC14 is commonly used to study hepatotoxicity, for it can copy liver damage perfectly. In this well-characterized model of free更多还原