LuXuRies of Lipid Homeostasis: The Unity of Nuclear Hormone Receptors, Transcription Regulation, and Cholesterol Sensing

Model describing the LXR regulatory pathways governing lipid metabolism.

In liver, intestine, and macrophages, LXRs regulate the expression of genes involved in bile acid synthesis (green box), fatty acid synthesis (red boxes), and cholesterol efflux and transport (blue boxes). LXRs sense intracellular cholesterol levels to help maintain cholesterol homeostasis by increasing bile acid excretion, reducing cholesterol absorption, and increasing cholesterol transport back to the liver for catabolism and storage. (C, cholesterol; CE, cholesterol ester; BA, bile acid; FA, fatty acid; TG, triglyceride; HDL, high density lipoprotein; VLDL, very low density lipoprotein; LDL, low density lipoprotein. See text for details.)