Liver X receptor in the cardiovascular system

PhD ceremony: Ms. I. Kuipers, 13.15 uur, Academiegebouw, Broerstraat 5, Groningen

Title: Liver X receptor in the cardiovascular system

Promotor(s): prof. W.H. van Gilst, prof. D.J. van Veldhuisen

Faculty: Medical Scienes

Liver X receptors (LXRs) are nuclear hormone receptors that act as ligand-activated transcription factors. They are critically involved in cholesterol metabolism and their natural ligands are oxysterols; oxidized cholesterol derivatives. There are two known isoforms of LXRs; LXR-α (mainly expressed in liver, spleen, intestine, macrophages, heart and kidney) and LXR-β (expressed ubiquitously). Over the last decade, research on LXRs was mainly focused on their role in cholesterol metabolism. It was discovered that LXRs play a crucial role in the process of ‘reverse cholesterol metabolism’; the efflux of cholesterol from peripheral tissues towards the liver for excretion. More recent studies show that LXRs also exert pleiotropic properties. They have been shown to attenuate proliferative pathways, blunt inflammatory responses, and influence the renin-angiotensin-aldosterone system (RAAS).