Department of Dermatology, University of Alabama at Birmingham, 1670 University Blvd, Rm 476, Birmingham, AL, 35249, USA.
Comprehensive Cancer Center, Cancer Chemoprevention Program, University of Alabama at Birmingham, Birmingham, AL, 35249, USA.
Sci Rep. 2021 Apr 13;11(1):8002. doi: 10.1038/s41598-021-87061-w.
The interactions of derivatives of lumisterol (L3) and vitamin D3 (D3) with liver X receptors (LXRs) were investigated. Molecular docking using crystal structures of the ligand binding domains (LBDs) of LXRα and β revealed high docking scores for L3 and D3 hydroxymetabolites, similar to those of the natural ligands, predicting good binding to the receptor. RNA sequencing of murine dermal fibroblasts stimulated with D3-hydroxyderivatives revealed LXR as the second nuclear receptor pathway for several D3-hydroxyderivatives, including 1,25(OH)D3. This was validated by their induction of genes downstream of LXR. L3 and D3-derivatives activated an LXR-response element (LXRE)-driven reporter in CHO cells and human keratinocytes, and by enhanced expression of LXR target genes. L3 and D3 derivatives showed high affinity binding to the LBD of the LXRα and β in LanthaScreen TR-FRET LXRα and β coactivator assays. The majority of metabolites functioned as LXRα/β agonists; however, 1,20,25(OH)D3, 1,25(OH)D3, 1,20(OH)D3 and 25(OH)D3 acted as inverse agonists of LXRα, but as agonists of LXRβ. Molecular dynamics simulations for the selected compounds, including 1,25(OH)D3, 1,20(OH)D3, 25(OH)D3, 20(OH)D3, 20(OH)L3 and 20,22(OH)L3, showed different but overlapping interactions with LXRs. Identification of D3 and L3 derivatives as ligands for LXRs suggests a new mechanism of action for these compounds.
研究了维生素 D3（D3）及其衍生物 Lumisterol（L3）与肝 X 受体（LXR）的相互作用。利用 LXRα和β配体结合域（LBD）的晶体结构进行分子对接，结果表明 L3 和 D3 的羟代谢产物与天然配体具有相似的高对接评分，预测与受体具有良好的结合能力。用 D3 羟衍生物刺激的鼠真皮成纤维细胞进行 RNA 测序，结果表明 LXR 是几种 D3 羟衍生物的第二个核受体途径，包括 1,25（OH）D3。这一点通过它们对 LXR 下游基因的诱导得到了验证。L3 和 D3 衍生物在 CHO 细胞和人角质形成细胞中激活了 LXR 反应元件（LXRE）驱动的报告基因，并增强了 LXR 靶基因的表达。L3 和 D3 衍生物在 LanthaScreen TR-FRET LXRα 和β辅激活剂测定中与 LXRα 和β 的 LBD 具有高亲和力结合。大多数代谢物作为 LXRα/β激动剂发挥作用；然而，1,20,25（OH）D3、1,25（OH）D3、1,20（OH）D3 和 25（OH）D3 作为 LXRα 的反向激动剂，但作为 LXRβ 的激动剂。对选定化合物（包括 1,25（OH）D3、1,20（OH）D3、25（OH）D3、20（OH）D3、20（OH）L3 和 20,22（OH）L3）进行分子动力学模拟，结果表明它们与 LXR 具有不同但重叠的相互作用。D3 和 L3 衍生物被鉴定为 LXR 的配体，这表明这些化合物具有新的作用机制。
