Kamiyama S, Kim H J, Furukawa Y
Department of Applied Biological Chemistry, Faculty of Agriculture, Tohoku University, Sendai, Japan.
Biosci Biotechnol Biochem. 1996 Apr;60(4):580-3. doi: 10.1271/bbb.60.580.
Lecithin: cholesterol acyltransferase (LCAT) is an enzyme that is important in the cholesterol reverse-transport system by converting the surface cholesterol of high-density lipoprotein (HDL) to cholesterol ester inside HDL. We have investigated changes in plasma LCAT activity induced by oxidized low-density lipoprotein (ox-LDL). (i) LCAT activity was inhibited by the addition of even a small amount of ox-LDL, (ii) This inhibitory effect was dose-dependent and was related to the degree of oxidation of LDL, (iii) As this inhibitory effect was not prevented by antioxidants, it is suggested that it does not occur via oxidation of substrate HDL. These results suggest that cholesterol reverse-transport via HDL may be affected by ox-LDL and they are noteworthy in suggesting a new physiological function for ox-LDL.
卵磷脂胆固醇酰基转移酶（LCAT）是一种在胆固醇逆向转运系统中起重要作用的酶，它能将高密度脂蛋白（HDL）表面的胆固醇转化为HDL内部的胆固醇酯。我们研究了氧化低密度脂蛋白（ox-LDL）诱导的血浆LCAT活性变化。（i）即使添加少量ox-LDL也会抑制LCAT活性；（ii）这种抑制作用呈剂量依赖性，且与LDL的氧化程度有关；（iii）由于抗氧化剂不能阻止这种抑制作用，提示其并非通过底物HDL的氧化发生。这些结果表明，通过HDL的胆固醇逆向转运可能受ox-LDL影响，并且这些结果在提示ox-LDL的新生理功能方面值得关注。
