title: Cholesterol esters (CE) derived from hepatic sterol O-acyltransferase 2 (SOAT2) are associated with more atherosclerosis than CE from intestinal SOAT2.
abstract: BACKGROUND
  Cholesterol esters (CE), especially cholesterol oleate, generated by hepatic and intestinal sterol O-acyltransferase 2 (SOAT2) play a critical role in cholesterol homeostasis. However, it is unknown whether the contribution of intestine-derived CE from SOAT2 would have similar effects in promoting atherosclerosis progression as for liver-derived CE.
  
  
  OBJECTIVE
  To test whether, in low-density lipoprotein receptor null (LDLr(-/-)) mice, the conditional knockout of intestinal SOAT2 (SOAT2(SI-/SI-)) or hepatic SOAT2 (SOAT2(L-/L-)) would equally limit atherosclerosis development compared with the global deletion of SOAT2 (SOAT2(-/-)).
  
  
  RESULTS
  SOAT2 conditional knockout mice were bred with LDLr(-/-) mice creating LDLr(-/-) mice with each of the specific SOAT2 gene deletions. All mice then were fed an atherogenic diet for 16 weeks. SOAT2(SI-/SI-)LDLr(-/-) and SOAT2(-/-)LDLr(-/-) mice had significantly lower levels of intestinal cholesterol absorption, more fecal sterol excretion, and lower biliary cholesterol levels. Analysis of plasma LDL showed that all mice with SOAT2 gene deletions had LDL CE with reduced percentages of cholesterol palmitate and cholesterol oleate. Each of the LDLr(-/-) mice with SOAT2 gene deletions had lower accumulations of total cholesterol and CE in the liver compared with control mice. Finally, aortic atherosclerosis development was significantly lower in all mice with global or tissue-restricted SOAT2 gene deletions. Nevertheless, SOAT2(-/-)LDLr(-/-) and SOAT2(L-/L-)LDLr(-/-) mice had less aortic CE accumulation and smaller aortic lesions than SOAT2(SI-/SI-)LDLr(-/-) mice.
  
  
  CONCLUSIONS
  SOAT2-derived CE from both the intestine and liver significantly contribute to the development of atherosclerosis, although the CE from the hepatic enzyme appeared to promote more atherosclerosis development.
authors.affiliation: From the Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (J.Z., J.K.S., S.M.M., K.L.K., M.A.D., M.D.W., L.L.R.); and Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, OH (S.M.M., J.M.B.).
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: From the Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (J.Z., J.K.S., S.M.M., K.L.K., M.A.D., M.D.W., L.L.R.); and Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, OH (S.M.M., J.M.B.).
authors.forename: Janet K
authors.initials: JK
authors.lastname: Sawyer
authors.affiliation: From the Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (J.Z., J.K.S., S.M.M., K.L.K., M.A.D., M.D.W., L.L.R.); and Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, OH (S.M.M., J.M.B.).
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Marshall
authors.affiliation: From the Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (J.Z., J.K.S., S.M.M., K.L.K., M.A.D., M.D.W., L.L.R.); and Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, OH (S.M.M., J.M.B.).
authors.forename: Kathryn L
authors.initials: KL
authors.lastname: Kelley
authors.affiliation: From the Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (J.Z., J.K.S., S.M.M., K.L.K., M.A.D., M.D.W., L.L.R.); and Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, OH (S.M.M., J.M.B.).
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Davis
authors.affiliation: From the Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (J.Z., J.K.S., S.M.M., K.L.K., M.A.D., M.D.W., L.L.R.); and Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, OH (S.M.M., J.M.B.).
authors.forename: Martha D
authors.initials: MD
authors.lastname: Wilson
authors.affiliation: From the Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (J.Z., J.K.S., S.M.M., K.L.K., M.A.D., M.D.W., L.L.R.); and Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, OH (S.M.M., J.M.B.).
authors.forename: J Mark
authors.initials: JM
authors.lastname: Brown
authors.affiliation: From the Section on Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (J.Z., J.K.S., S.M.M., K.L.K., M.A.D., M.D.W., L.L.R.); and Department of Cellular and Molecular Medicine, Cleveland Clinic Lerner Research Institute, OH (S.M.M., J.M.B.). lrudel@wakehealth.edu.
authors.forename: Lawrence L
authors.initials: LL
authors.lastname: Rudel
mesh_terms: D000818:Animals; D001011:Aorta / Q000378:metabolism* / Q000473:pathology; D050197:Atherosclerosis / Q000097:blood / Q000378:metabolism* / Q000473:pathology; D002788:Cholesterol Esters / Q000097:blood / Q000378:metabolism*; D005260:Female; D007408:Intestinal Absorption / Q000502:physiology*; D008099:Liver / Q000378:metabolism*; D008297:Male; D051379:Mice; D057507:Mice, 129 Strain; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D002785:Sterol O-Acyltransferase / Q000172:deficiency*; D000097587:Sterol O-Acyltransferase 2
chemical_list: D002788:Cholesterol Esters; D002785:Sterol O-Acyltransferase; D000097587:Sterol O-Acyltransferase 2
keywords: atherosclerosis; cholesterol esters; molecular biology; sterol O-acyltransferase 2