24(R)-hydroxy Cholesterol (Synonyms: 24-Epicerebrosterol)

EC50: 7 and 4 μM for LXRα and LXRβ, respectively

24(R)-hydroxy Cholesterol is a LXRα and LXRβ nuclear receptors activator.

The liver X receptors (LXRs) are identified as orphan members of the nuclear receptor superfamily. Like other receptors in the family, LXRs heterodimerize with RXR and bind to specific response elements. LXRα and β are nuclear receptors regulating the metabolism of several important lipids, such as cholesterol and bile acids.

In vitro: In previous study, the authors proposed that LXRs could regulate the lipid metabolism via their interaction with specific oxysterols, such as 24(R)-hydroxycholesterol, 22(R)-hydroxycholesterol, 24(S)-hydroxycholesterol, and 24(S),25-epoxycholesterol. Results showed that by using a ligand binding assay, it was demonstrated that these oxysterols could directly bind to LXRs. In addition, this study further revealed that the position-specific monooxidation of the sterol side chain was required for LXR binding and activation. Enhanced binding and activation could be achieved via the use of 24-oxo ligands. Moreover, the introduction of an oxygen on the sterol B-ring led to a LXRa-subtype selectivity [1].

In vivo: Up to now, there is no animal in vivo data reported.

Clinical trial: So far, no clinical study has been conducted.

Reference:
[1] Janowski, B. A.,Grogan, M.J.,Jones, S.A., et al. Structural requirements of ligands for the oxysterol liver X receptors LXRα and LXRβ. Proceedings of the National Academy of Sciences of the United States of America 96(1), 266-271 (1999).