Estrogens inhibit copper and cell-mediated modification of low density lipoprotein

doi:10.1016/0021-9150(91)90058-B

Atherosclerosis

Volume 89, Issues 2–3, August 1991, Pages 175-182

https://doi.org/10.1016/0021-9150(91)90058-B Get rights and content

Abstract

The effects of estrogens on LDL modification by copper ions, U 937 monocyte-like cells or endothelial cells was studied by determination of the lipid peroxidation product content and measurement of the relative electrophoretic mobility. The presence of estradiol, estriol and estrone inhibited LDL oxidation in a dose-dependent manner in the range of concentrations from 5 to 50 μM. In the case of oxidation by Cu²⁺, the decreasing order of efficiency was: estradiol, estriol, estrone. In monocyte-induced oxidation, the protective effect of estrogens was more marked, and the order of efficiency was the same, except that estrone was as active as estriol. Pretreatment of monocyte cells with estrogens also inhibited the subsequent modification of LDL by these cells, tested in the absence of the hormones. Testosterone had no effect in all the studied systems. Furthermore, the degradation by J774 macrophage like cells of LDL modified either by Cu²⁺ or monocytes was markedly reduced when modification has been performed in the presence of estrogens. Since oxidative modification of LDL is believed to be involved in the appearance of atherosclerotic plaques, this effect of estrogens might be related to their protective action against atherosclerosis.

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Research articleEstrogens inhibit copper and cell-mediated modification of low density lipoprotein

Abstract

J. Biol. Chem.

Free Radicals Biol. Med.

J. Lip. Res.

Am. J. Cardiol.

Metabolism

Biochim. Biophys. Acta

Chem. Phys. Lipids

J. Biol. Chem.

FEBS Lett.

FEBS Lett.

J. Biol. Chem.

Biochem. Biophys. Res. Commun.

The role of the monocyte in atherosclerosis; I. transition of blood-born monocytes into foam cells in fatty lesions

Am. J. Pathol.

Characterization of lipid-laden aortic cells from cholesterol fed rabbits. IV Investigation of macrophage-like properties of aortic cell populations

Lab. Invest.

Enhanced macrophage degradation of low density lipoprotein previously incubated with cultured endothelial cells: recognition by the receptor for acetylated low density lipoproteins

Endothelial and smooth muscle cells alter low density lipoprotein in vitro by free radical oxidation

Arteriosclerosis

Monocytes and neutrophils oxidize low density lipoproteins making it cytotoxic

J. Leukocyte Biol.

Macrophage oxidation of low density lipoprotein generates a modified form recognized by the scavenger receptor

Arteriosclerosis

Decrease in reactive amino groups during oxidation or endothelial modification of LDL. Correlation with changes in receptor-mediated catabolism

Arteriosclerosis

Research article
Estrogens inhibit copper and cell-mediated modification of low density lipoprotein