Malmendier C L, Delcroix C, Fontaine M
Atherosclerosis. 1980 Oct;37(2):277-84. doi: 10.1016/0021-9150(80)90013-1.
This study was undertaken to determine whether sialic acid removal alters the catabolism of low density lipoprotein in humans. Human low density lipoproteins labeled in vitro with 125I were incubated in the presence (termed desialylated) or absence (sialylated) of neuraminidase. The treatment with neuraminidase from Clostridium perfringens removed 90% of the sialic acid residues which did not change the chemical composition of the lipoproteins. Sialylated or desialylated LDL were injected intravenously into normal human subjects. The mathematical analysis of the plasma radioactivity decay curves (followed for 220 h) of desialylated low density lipoproteins, when compared with sialylated LDL, showed a shorter mean transit time (51 h vs 60 h), a 52% faster metabolic catabolic rate and an increased volume of distribution. The data are consistent with a proposed metabolism of low density lipoproteins: in humans, desialylation appears to accelerate the first step of the low density lipoprotein conversion but not to alter its final catabolism.
本研究旨在确定唾液酸去除是否会改变人类低密度脂蛋白的分解代谢。用125I体外标记的人低密度脂蛋白在存在（称为去唾液酸化）或不存在（唾液酸化）神经氨酸酶的情况下进行孵育。用产气荚膜梭菌的神经氨酸酶处理可去除90%的唾液酸残基，而这并未改变脂蛋白的化学组成。将唾液酸化或去唾液酸化的低密度脂蛋白静脉注射到正常人类受试者体内。与唾液酸化的低密度脂蛋白相比，对去唾液酸化的低密度脂蛋白血浆放射性衰变曲线（跟踪220小时）进行数学分析，结果显示平均转运时间更短（51小时对60小时），代谢分解率快52%，分布容积增加。这些数据与所提出的低密度脂蛋白代谢一致：在人类中，去唾液酸化似乎会加速低密度脂蛋白转化的第一步，但不会改变其最终分解代谢。
