Enhanced degradation of low density lipoprotein in human monocyte-derived macrophages associated with an increase in its free fatty acid content

Abstract

Low density lipoprotein (LDL) rich in oleic acid (designated FFA-rich LDL) was produced by the reconstitution technique. FFA-rich LDL, like acetyl LDL, moved faster than native LDL in agarose gel electrophoresis. While FFA-rich LDL was observed to degrade far less than natural LDL in lymphocytes, its degradation in monocyte-derived macrophages was three times higher than that of natural LDL or LDL reconstituted without the addition of oleic acid. A competitive study showed that the catabolism of FFA-rich LDL in macrophages may be influenced by systems other than the acetyl LDL receptor.