Clinically used selective estrogen receptor modulators affect different steps of macrophage-specific reverse cholesterol transport

• Published in: Scientific reports Vol. 6; no. 1; p. 32105
• Main Authors: Fernández-Suárez, María E., Escolà-Gil, Joan C., Pastor, Oscar, Dávalos, Alberto, Blanco-Vaca, Francisco, Lasunción, Miguel A., Martínez-Botas, Javier, Gómez-Coronado, Diego
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 07.09.2016; Nature Publishing Group
• Subjects: 13; 14; 14/19; 14/34; 14/63; 17β-Estradiol; 38; 38/77; 631/45/287/1191; 64; 64/60; 692/163; 82; 82/1; 82/16; 82/29; 82/80; ABCA1 protein; Acetyl-CoA C-Acetyltransferase - antagonists & inhibitors; Animals; Antiestrogens; Apolipoprotein A; Apolipoprotein A-I; Apolipoprotein A-I - metabolism; ATP Binding Cassette Transporter 1 - biosynthesis; ATP Binding Cassette Transporter 1 - genetics; ATP Binding Cassette Transporter, Sub-Family G - biosynthesis; ATP Binding Cassette Transporter, Sub-Family G - genetics; ATP-binding protein; Biological Transport - drug effects; Cholesterol; Cholesterol - analysis; Cholesterol - blood; Cholesterol - metabolism; Cholesterol Esters - metabolism; Diet, Western; Esterification - drug effects; Estradiol - analogs & derivatives; Estradiol - pharmacology; Estrogen receptors; Estrogens; Feces - chemistry; High density lipoprotein; Homeostasis; Humanities and Social Sciences; Humans; Lipoproteins, HDL - metabolism; Lipoproteins, LDL - metabolism; Liver; Liver - chemistry; Liver - drug effects; Low density lipoprotein; Macrophages; Macrophages - drug effects; Macrophages - metabolism; Male; Mice; Mice, Inbred C57BL; multidisciplinary; Protein transport; Raloxifene; Raloxifene Hydrochloride - pharmacology; Science; Science (multidisciplinary); Selective estrogen receptor modulators; Selective Estrogen Receptor Modulators - pharmacology; Tamoxifen; Tamoxifen - pharmacology; THP-1 Cells; Toremifene; Toremifene - pharmacology
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep32105

Selective estrogen receptor modulators (SERMs) are widely prescribed drugs that alter cellular and whole-body cholesterol homeostasis. Here we evaluate the effect of SERMs on the macrophage-specific reverse cholesterol transport (M-RCT) pathway, which is mediated by HDL. Treatment of human and mouse macrophages with tamoxifen, raloxifene or toremifene induced the accumulation of cytoplasmic vesicles of acetyl-LDL-derived free cholesterol. The SERMs impaired cholesterol efflux to apolipoprotein A-I and HDL, and lowered ABCA1 and ABCG1 expression. These effects were not altered by the antiestrogen ICI 182,780 nor were they reproduced by 17β-estradiol. The treatment of mice with tamoxifen or raloxifene accelerated HDL-cholesteryl ester catabolism, thereby reducing HDL-cholesterol concentrations in serum. When [ 3 H]cholesterol-loaded macrophages were injected into mice intraperitoneally, tamoxifen, but not raloxifene, decreased the [ 3 H]cholesterol levels in serum, liver and feces. Both SERMs downregulated liver ABCG5 and ABCG8 protein expression, but tamoxifen reduced the capacity of HDL and plasma to promote macrophage cholesterol efflux to a greater extent than raloxifene. We conclude that SERMs interfere with intracellular cholesterol trafficking and efflux from macrophages. Tamoxifen, but not raloxifene, impair M-RCT in vivo . This effect is primarily attributable to the tamoxifen-mediated reduction of the capacity of HDL to promote cholesterol mobilization from macrophages.