Triglyceride-rich lipoproteins from apolipoprotein E3/2 subjects with hypertriglyceridemia enhance cholesteryl ester synthesis in human macrophages.
The ability of triglyceride (TG)-rich lipoproteins from apolipoprotein (apo) E2 heterozygote, apo E3/2 which is relatively common, to stimulate cholesteryl ester synthesis in human monocyte-derived macrophages was studied to clarify the atherogenicity of apo E3/2. Twenty-three subjects were randomly sampled from our hospitals, and divided into the following 4 groups: 7 apo E3/3 subjects with normolipidemia, 6 apo E3/3 subjects with hypertriglyceridemia (HTG), 5 apo E3/2 subjects with normolipidemia and 5 apo E3/2 subjects with HTG. Plasma levels of TG and total cholesterol (chol) were significantly (P < 0.001) higher in apo E3/3 and apo E3/2 subjects with HTG than in apo E3/3 and apo E3/2 subjects with normolipidemia, but plasma levels of TG and total chol were not significantly different between apo E3/3 and apo E3/2 subjects with HTG. [14C]oleate incorporation into cholesteryl esters in macrophages was significantly (P < 0.001) higher in apo E3/2 subjects with HTG (0.661 nmol/mg cell protein) than in apo E3/3 subjects with normolipidemia (0.228) and with HTG (0.325) and in apo E3/2 subjects with normolipidemia (0.257). It is concluded that TG-rich lipoproteins from apolipoprotein E3/2 subjects with HTG enhance cholesteryl ester synthesis in human macrophages.
Saito
M
M
Second Department of Internal Medicine, Asahikawa Medical College, Japan.
Eto
M
M
Makino
I
I
D053329:Apolipoprotein E2; D053318:Apolipoprotein E3; D001057:Apolipoproteins E / Q000097:blood* / Q000235:genetics; D002788:Cholesterol Esters / Q000096:biosynthesis*; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005838:Genotype; D006801:Humans; D015228:Hypertriglyceridemia / Q000097:blood* / Q000235:genetics; D008074:Lipoproteins / Q000097:blood; D053419:Lipoproteins, IDL; D008079:Lipoproteins, VLDL / Q000097:blood; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D011897:Random Allocation; D014280:Triglycerides / Q000097:blood
D053329:Apolipoprotein E2; D053318:Apolipoprotein E3; D001057:Apolipoproteins E; D002788:Cholesterol Esters; D008074:Lipoproteins; D053419:Lipoproteins, IDL; D008079:Lipoproteins, VLDL; D014280:Triglycerides