Role of estrogen in the regulation of cholesteryl ester synthesis in macrophages: the interaction between native and modified low density lipoprotein and human monocyte-derived macrophages.
OBJECTIVE
To study the effects of estrogen on the changes in cholesterol esterification induced by native and modified low density lipoprotein (LDL) in macrophages.


METHODS
Human monocyte-derived macrophages (HMDM) were used, and the influence of the presence of 17beta estradiol in the short term, and during the maturation of the cells, on the esterification of cholesterol from native (nLDL), acetylated (acLDL) and oxidized (oxLDL) LDL was determined.


RESULTS
In the short-term (6 h), 17beta estradiol (1.5 x 10(-6)M) did not affect the esterification of cholesterol from acLDL or oxLDL, but with native LDL (nLDL) a 1.5-fold increase was observed. In contrast, long-term exposure of HMDM during maturation to 17beta-estradiol (1.5 x 10(-9)M - 1.5 x 10(-5)M) decreased cholesterol esterification in the presence of oxLDL and acLDL, but not nLDL.


CONCLUSIONS
These results suggest that both the time of exposure and the concentration of estrogen used influence its effects on the interaction between HMDM and LDL, and thus on macrophage foam cell formation.
Napolitano
Mariarosaria
M
Laboratory of Metabolism and Pathological Biochemistry, Instituto Superiore di Sanità, Rome, Italy.
Calcabrini
Annarica
A
Botham
Kathleen M
KM
Bravo
Elena
E
D002454:Cell Differentiation / Q000502:physiology; D002788:Cholesterol Esters / Q000096:biosynthesis*; D008076:Cholesterol, HDL / Q000378:metabolism; D008078:Cholesterol, LDL / Q000378:metabolism*; D004967:Estrogens / Q000378:metabolism*; D006801:Humans; D008264:Macrophages / Q000378:metabolism*; D009000:Monocytes / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000378:metabolism
D002788:Cholesterol Esters; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D004967:Estrogens; D011956:Receptors, Cell Surface