The contribution of the macrophage receptor for oxidized LDL to its cellular uptake.
Oxidized LDL (Ox-LDL) was shown to be taken up by macrophages via several receptors including the acetyl-LDL(Ac-LDL), the LDL, and the Ox-LDL receptors. Cellular uptake and degradation of Ox-LDL could be dissociated from that of LDL and Ac-LDL as demonstrated by using macrophages that lack the LDL or the Ac-LDL receptors. In J-774 A.1 macrophage-like cell line unlabeled Ox-LDL reduced the 125I-Ox-LDL by up to degradation of 91% whereas unlabeled Ac-LDL and native LDL reduced 125I-Ox-LDL degradation by only 51% and 23%, respectively. Analysis of macrophage degradation of 125I-Ox-LDL in the presence of 30-fold excess concentration of LDL + Ac-LDL (to block uptake of 125I-Ox-LDL via the LDL and the Ac-LDL receptors) revealed that cellular degradation via the Ox-LDL receptor could account for 45% of the macrophage uptake of Ox-LDL.
Aviram
M
M
Lipid Research Laboratory, Rambam Medical Center, Rappaport Family Institute for Research in the Medical Sciences, Technion Faculty of Medicine, Haifa, Israel.
D000818:Animals; D000925:Anticoagulants / Q000494:pharmacology*; D001667:Binding, Competitive; D001692:Biological Transport; D002460:Cell Line; D007700:Kinetics; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism*; D051379:Mice; D010084:Oxidation-Reduction; D011134:Polysaccharides / Q000494:pharmacology; D011973:Receptors, LDL / Q000378:metabolism*
D000925:Anticoagulants; D008077:Lipoproteins, LDL; D011134:Polysaccharides; D011973:Receptors, LDL; C007789:fucoidan