Cholesterol metabolism in monocyte-derived macrophages from macrophage colony-stimulating factor administered rabbits.
The metabolism of beta-very-low-density lipoproteins (beta-VLDL) in macrophages from the blood monocytes of rabbits, which had been administered macrophage colony-stimulating factor (M-CSF) in vivo, was investigated in order to clarify the mechanism of the suppressive effect of M-CSF on cholesterol accumulation in macrophages. Cholesterol ester content after incubation with beta-VLDL, and [3H]cholesterol oleate-beta-VLDL incorporation remarkably increased in cultured macrophages from blood monocytes in the high cholesterol diet control group compared to those in the normal diet control group. Those in macrophages from M-CSF-treated groups, both normal diet and high cholesterol diet, were the same as in the normal diet control group. The ratio of released [3H]cholesterol to incorporated [3H]cholesterol oleate-beta-VLDL in macrophages from control was smaller than that from the M-CSF group. The acyl-coenzyme A:cholesterol acyltransferase (ACAT) activity was enhanced in the high cholesterol diet groups, and the activity in M-CSF-treated groups decreased. The neutral cholesterol esterase activity was enhanced in the M-CSF-treated groups compared with that in the non-treated control groups. These results suggest that high cholesterol diet induced further cholesterol esterification and that M-CSF treatment enhanced cholesterol clearance in macrophages.
Ishii
I
I
Department of Biochemistry, Faculty of Pharmaceutical Science, Chiba University, Japan.
Kimuro
T
T
Saito
Y
Y
Hirose
S
S
D000818:Animals; D000924:Anticholesteremic Agents; D002454:Cell Differentiation; D002478:Cells, Cultured; D002784:Cholesterol / Q000378:metabolism*; D002791:Cholesterol, Dietary; D008079:Lipoproteins, VLDL / Q000378:metabolism*; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D009000:Monocytes / Q000166:cytology / Q000378:metabolism*; D011817:Rabbits
D000924:Anticholesteremic Agents; D002791:Cholesterol, Dietary; D008079:Lipoproteins, VLDL; D016173:Macrophage Colony-Stimulating Factor; D002784:Cholesterol