The cholesterol metabolite 27-hydroxycholesterol promotes atherosclerosis via proinflammatory processes mediated by estrogen receptor alpha.

ABSTRACT: Oxysterols are cholesterol metabolites that serve multiple functions in lipid metabolism, including as liver X receptor (LXR) ligands. 27-hydroxycholesterol (27HC) is an abundant oxysterol metabolized by CYP7B1. How 27HC impacts vascular health is unknown. We show that elevations in 27HC via cyp7b1 deletion promote atherosclerosis in apoe(-/-) mice without altering lipid status; furthermore, estrogen-related atheroprotection is attenuated. In wild-type mice, leukocyte-endothelial cell adhesion is increased by 27HC via estrogen receptor (ER)-dependent processes. In monocytes/macrophages, 27HC upregulates proinflammatory genes and increases adhesion via ER?. In endothelial cells, 27HC is also proadhesive via ER?, and in contrast to estrogen, which blunts NF-?B activation, 27HC stimulates NF-?B activation via Erk1,2 and JNK-dependent I?B? degradation. Whereas 27HC administration to apoe(-/-) mice increases atherosclerosis, apoe(-/-);er?(-/-) are unaffected. Thus, 27HC promotes atherosclerosis via proinflammatory processes mediated by ER?, and it attenuates estrogen-related atheroprotection. Strategies to lower 27HC may complement approaches targeting cholesterol to prevent vascular disease.

SUBMITTER: Umetani M 

PROVIDER: S-EPMC4098728 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature