22(R)-HYDROXYCHOLESTEROL

Description

The liver X receptors (LXRα and LXRβ) are nuclear hormone receptors whose native ligands are oxysterols. LXRs regulate the oxysterol-induced expression of cholesterol 7α-hydroxylase, the rate limiting enzyme of classic bile acid synthesis. 22(R)-hydroxy Cholesterol is an endogenous agonist for LXRs that activates LXRα with an EC₅₀ value of 325 nM. 22(R)-hydroxy Cholesterol, acting through LXR heterodimerized with the retinoid X receptor, induces the expression of the ABCA1 reverse cholesterol transporter. This activity increases the efflux of cholesterol from enterocytes and thus inhibits the overall absorption of cholesterol. 22(R)-hydroxy Cholesterol can be used as a substrate to monitor cholesterol transport or as an endogenous positive control for testing LXR agonists which have potential as therapeutic agents for the treatment of atherosclerosis.

Uses

The 22R-metabolite of Cholesterol (C432501). 22-Hydroxycholesterol inhibits chemokine receptor activity.

Uses

Bovine aortic endothelial cells were treated with 22(R)-Hydroxycholesterol to study the effects on production of free radicals and in studies related to fatty acid metabolism.

Definition

ChEBI: An oxysterol that is the 22R-hydroxy derivative of cholesterol.

General Description

22(R)-hydroxycholesterol is a diastereomer of 22(S)-hydroxycholesterol. It is present in neonate brain.

Biochem/physiol Actions

22(R)-hydroxycholesterol (22(R)-HC) is a liver X receptor (LXR) ligand.. 22(R)-HC in combination with other oxysterols promote mesenchymal stem cell osteogenesis. It regulates cholesterol homeostasis. Low levels of 22(R)-HC is observed in Alzheimer′s disease and it may be implicated in neuroinflammation and neurodegenerative diseases. 22(R)-hydroxycholesterol also suppresses prostate tumor progression.