The liver x receptors (LXRα and LXRβ) are nuclear hormone receptors whose native ligands, oxysterols, induce the expression of genes involved in cholesterol and fatty acid metabolism. 27-hydroxy Cholesterol, a sterol 27-hydroxylase-mediated cholesterol hydroxylation product, activates LXRα and LXRβ in vitro with EC50 values of 85 and 71 nM, respectively, and is a potent suppressor of cholesterol biosynthesis. 25(R)-27-hydroxy Cholesterol is the more predominant-occurring (~80%) stereoisomer of the endogenous oxysterol 27-hydroxy cholesterol.
