Clinically used selective estrogen receptor modulators affect different steps of macrophage-specific reverse cholesterol transport.
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.
Servicio de Bioquímica-Investigación, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain.|CIBER de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Madrid, Spain.
María E
ME
Fernández-Suárez
Institut d'Investigacions Biomèdiques (IIB) Sant Pau, Barcelona, Spain.|Departament de Bioquímica i Biología Molecular, Universitat Autònoma de Barcelona, Bellaterra, Spain.|CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Spain.
Joan C
JC
Escolà-Gil
CIBER de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Madrid, Spain.|Servicio de Bioquímica Clínica, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain.
Oscar
O
Pastor
Instituto Madrileño de Estudios Avanzados (IMDEA)-Alimentación, Madrid, Spain.
Alberto
A
Dávalos
Institut d'Investigacions Biomèdiques (IIB) Sant Pau, Barcelona, Spain.|Departament de Bioquímica i Biología Molecular, Universitat Autònoma de Barcelona, Bellaterra, Spain.|CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Spain.
Francisco
F
Blanco-Vaca
Servicio de Bioquímica-Investigación, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain.|CIBER de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Madrid, Spain.
Miguel A
MA
Lasunción
Servicio de Bioquímica-Investigación, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain.|CIBER de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Madrid, Spain.
Javier
J
Martínez-Botas
Servicio de Bioquímica-Investigación, Hospital Universitario Ramón y Cajal, IRYCIS, Madrid, Spain.|CIBER de Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Madrid, Spain.
Diego
D
Gómez-Coronado
D064286:ATP Binding Cassette Transporter 1 / Q000096:biosynthesis / Q000235:genetics; D000070996:ATP Binding Cassette Transporter, Subfamily G / Q000096:biosynthesis / Q000235:genetics; D000101:Acetyl-CoA C-Acetyltransferase / Q000037:antagonists & inhibitors; D000818:Animals; D016632:Apolipoprotein A-I / Q000378:metabolism; D001692:Biological Transport / Q000187:drug effects; D002784:Cholesterol / Q000032:analysis / Q000097:blood / Q000378:metabolism*; D002788:Cholesterol Esters / Q000378:metabolism; D066273:Diet, Western; D004951:Esterification / Q000187:drug effects; D004958:Estradiol / Q000031:analogs & derivatives / Q000494:pharmacology; D005243:Feces / Q000737:chemistry; D000077267:Fulvestrant; D006801:Humans; D008075:Lipoproteins, HDL / Q000378:metabolism*; D008077:Lipoproteins, LDL / Q000378:metabolism; D008099:Liver / Q000737:chemistry / Q000187:drug effects; D008264:Macrophages / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D020849:Raloxifene Hydrochloride / Q000494:pharmacology; D020845:Selective Estrogen Receptor Modulators / Q000494:pharmacology*; D000074084:THP-1 Cells; D013629:Tamoxifen / Q000494:pharmacology; D017312:Toremifene / Q000494:pharmacology
D064286:ATP Binding Cassette Transporter 1; D000070996:ATP Binding Cassette Transporter, Subfamily G; D000101:Acetyl-CoA C-Acetyltransferase; D016632:Apolipoprotein A-I; D002784:Cholesterol; D002788:Cholesterol Esters; D004958:Estradiol; D000077267:Fulvestrant; D008075:Lipoproteins, HDL; D008077:Lipoproteins, LDL; D020849:Raloxifene Hydrochloride; D020845:Selective Estrogen Receptor Modulators; D013629:Tamoxifen; D017312:Toremifene; C577833:Abca1 protein, mouse; C032629:acetyl-LDL; C506639:ACAT1 protein, human