Foam cells from aorta and spleen overexpress apolipoprotein E in the absence of hypercholesterolemia.
We have studied Apo E expression in atherosclerotic lesions and spleens in rabbits after a cholesterol-rich diet is discontinued and plasma cholesterol levels return to normal values. After 16 weeks, foam cells are still present in the atherosclerotic lesions and Apo E expression persists restricted solely to the lesion as ascertained by in situ RNA hybridization and northern blot. Apo E expression is induced in spleens of hypercholesterolemic rabbits. However Apo E mRNA levels decrease in this organ parallel to the disappearance of lipid loaded macrophages. These results of in vivo studies indicate that Apo E overexpression in foam cells does not depend on high serum cholesterol levels, but is a characteristic of macrophages that have acquired the foam cell phenotype.
Crespo
P
P
Departamento de Biología Molecular, Facultad de Medicina, Universidad de Cantabria, Santander, Spain.
Ros
M A
MA
Ordovás
J M
JM
Rodriguez
J C
JC
Ortiz
J M
JM
León
J
J
D000818:Animals; D001011:Aorta / Q000473:pathology; D001057:Apolipoproteins E / Q000235:genetics* / Q000302:isolation & purification; D001161:Arteriosclerosis / Q000378:metabolism*; D002784:Cholesterol / Q000097:blood; D002791:Cholesterol, Dietary / Q000494:pharmacology; D005260:Female; D005487:Foam Cells / Q000187:drug effects / Q000378:metabolism*; D005786:Gene Expression Regulation; D006937:Hypercholesterolemia / Q000378:metabolism*; D008074:Lipoproteins / Q000097:blood; D009693:Nucleic Acid Hybridization; D012333:RNA, Messenger / Q000032:analysis*; D011817:Rabbits; D013154:Spleen / Q000473:pathology
D001057:Apolipoproteins E; D002791:Cholesterol, Dietary; D008074:Lipoproteins; D012333:RNA, Messenger; D002784:Cholesterol