Lipid accumulation and foam cell formation in Chinese hamster ovary cells overexpressing very low density lipoprotein receptor.
The rabbit very low density lipoprotein receptor gene was introduced into LDL receptor-negative Chinese hamster ovary cells (ldl-A7). Incubation of the transfected cells with rabbit beta-VLDL (5 to 8 micrograms protein/ml), for 6 days, induced foam cell formation. The cells accumulated lipid droplets visualized by oil red-O staining; the cellular cholesteryl ester and triglyceride content increased two- to threefold. [3H]Oleate incorporation into cholesteryl [3H]oleate was stimulated threefold by incubation of cells with beta-VLDL (20 micrograms protein/ml). Northern blot analysis revealed the presence of VLDL receptor mRNA in rabbit resident alveolar macrophages. Incubation of the macrophages with beta-VLDL (20 micrograms protein/ml) for 24 hours induced foam cell formation but had virtually no effect on VLDL receptor mRNA abundance. These results suggest that the VLDL receptor on macrophages may play an important role in foam cell formation.
Third Department of Internal Medicine, Fukui Medical School, Japan.
J
J
Suzuki
S
S
Takahashi
K
K
Oida
A
A
Shimada
M
M
Kohno
T
T
Tamai
S
S
Miyabo
T
T
Yamamoto
T
T
Nakai
D000818:Animals; D015152:Blotting, Northern; D016466:CHO Cells / Q000378:metabolism*; D002788:Cholesterol Esters / Q000378:metabolism; D006224:Cricetinae; D005487:Foam Cells / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D050356:Lipid Metabolism; D008079:Lipoproteins, VLDL / Q000494:pharmacology; D016676:Macrophages, Alveolar / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D019301:Oleic Acid; D009829:Oleic Acids / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D011817:Rabbits; D011973:Receptors, LDL / Q000235:genetics*; D014162:Transfection; D014316:Tritium
D002788:Cholesterol Esters; D008079:Lipoproteins, VLDL; D009829:Oleic Acids; D012333:RNA, Messenger; D011973:Receptors, LDL; C036053:VLDL receptor; D014316:Tritium; D019301:Oleic Acid; C014409:cholesteryl oleate