79066-03-8Relevant articles and documents
Pharmacophore analysis of the nuclear oxysterol receptor LXRα
Spencer,Li,Russel,Collins,Bledsoe,Consler,Moore,Galardi,McKee,Moore,Watson,Parks,Lambert,Willson
, p. 886 - 897 (2001)
A cell-free assay was developed for the orphan nuclear receptor LXRα that measures the ligand-dependent recruitment of a peptide from the steroid receptor coactivator 1 (SRC1) to the nuclear receptor. Using this ligand-sensing assay (LiSA), the structural requirements for activation of the receptor by oxysterols and related compounds were studied. The minimal pharmacophore for receptor activation was shown to be a sterol with a hydrogen bond acceptor at C24.24(S),25-Epoxycholesterol (1), which meets this criterion, is among the most efficacious of the oxysterols and is an attractive candidate as the LXRα natural hormone. Cholenic acid dimethylamide (14) showed increased efficacy compared to 1, whereas the unnatural oxysterol 22(S)-hydroxycholesterol (4) was shown to be an antagonist of 1 in the LiSA. The structural requirements for SRC1 recruitment in the LiSA correlated with the transcriptional activity of compounds in a cell-based reporter assay employing LXRα-GAL4 chimeric receptors. Site-directed mutagenesis identified Trp443 as an amino acid critical for activation of LXRα by oxysterol ligands. This information was combined with the structure-activity relationship developed from the LiSA to develop a 3D homology model of LXRα. This model may aid the design of synthetic drugs targeted at this transcriptional regulator of cholesterol homeostasis.
Synthesis and activity evaluation of a series of cholanamides as modulators of the liver X receptors
Martínez, Mario D.,Ghini, Alberto A.,Dansey, M. Virginia,Veleiro, Adriana S.,Pecci, Adali,Alvarez, Lautaro D.,Burton, Gerardo
, p. 1092 - 1101 (2018/02/19)
The Liver X receptors (LXRs) are members of the nuclear receptor family, that play fundamental roles in cholesterol transport, lipid metabolism and modulation of inflammatory responses. In recent years, the synthetic steroid N,N-dimethyl-3β-hydroxycholenamide (DMHCA) arised as a promising LXR ligand. This compound was able to dissociate certain beneficial LXRs effects from those undesirable ones involved in triglyceride metabolism. Here, we synthetized a series of DMHCA analogues with different modifications in the steroidal nucleus involving the A/B ring fusion, that generate changes in the overall conformation of the steroid. The LXRα and LXRβ activity of these analogues was evaluated by using a luciferase reporter assay in BHK21 cells. Compounds were tested in both the agonist and antagonist modes. Results indicated that the agonist/antagonist profile is dependent on the steroid configuration at the A/B ring junction. Notably, in contrast to DMHCA, the amide derived from lithocholic acid (2) with an A/B cis configuration and its 6,19-epoxy analogue 4 behaved as LXRα selective agonists, while the 2,19-epoxy analogues with an A/B trans configuration were antagonists of both isoforms. The binding mode of the analogues to both LXR isoforms was assessed by using 50 ns molecular dynamics (MD) simulations. Results revealed conformational differences between LXRα- and LXRβ-ligand complexes, mainly in the hydrogen bonding network that involves the C-3 hydroxyl. Overall, these results indicate that the synthetized DMHCA analogues could be interesting candidates for a therapeutic modulation of the LXRs.
