E-LDL and Ox-LDL differentially regulate ceramide and cholesterol raft microdomains in human Macrophages.
Atherosclerosis is characterized by the generation of lipid-loaded macrophage-derived foam cells. To study the effect of different types of atherogenic lipoproteins, human macrophages were loaded with enzymatically degraded low density lipoprotein (E-LDL) or oxidized LDL (Ox-LDL). Cellular cholesterol content was increased by E-LDL, whereas Ox-LDL increased the ceramide content. Cell surface expression analysis by flow cytometry and confocal microscopy revealed that Ox-LDL increased ceramide and lactosylceramide expression compared to E-LDL loading and induced ceramide rafts, whereas loading with E-LDL induced cholesterol-rich microdomains. Formation of different rafts may have consequences for raft associated signaling in cholesterol homeostasis and apoptosis in human macrophages.
Grandl
Margot
M
Institute for Clinical Chemistry and Laboratory Medicine, University of Regensburg, 93042 Regensburg, Germany.
Bared
Salim Maa
SM
Liebisch
Gerhard
G
Werner
Tobias
T
Barlage
Stefan
S
Schmitz
Gerd
G
D015703:Antigens, CD / Q000032:analysis / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D002518:Ceramides / Q000032:analysis / Q000378:metabolism*; D002784:Cholesterol / Q000032:analysis / Q000378:metabolism*; D005434:Flow Cytometry; D006801:Humans; D007790:Lactosylceramides / Q000032:analysis / Q000378:metabolism; D008077:Lipoproteins, LDL / Q000737:chemistry / Q000494:pharmacology*; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008563:Membrane Lipids / Q000032:analysis / Q000378:metabolism; D021962:Membrane Microdomains / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D009000:Monocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism
D015703:Antigens, CD; D002518:Ceramides; D007790:Lactosylceramides; D008077:Lipoproteins, LDL; D008563:Membrane Lipids; C099252:oxidized low density lipoprotein; C009744:CDw17 antigen; D016173:Macrophage Colony-Stimulating Factor; D002784:Cholesterol