Luciferase-based HMG-CoA reductase degradation assay for activity and selectivity profiling of oxy(lano)sterols

Bioorg Med Chem. 2020 Feb 1;28(3):115298. doi: 10.1016/j.bmc.2019.115298. Epub 2019 Dec 30.

Abstract

HMG-CoA reductase (HMGCR) is the rate-limiting enzyme in the cholesterol biosynthetic pathway, and is the target of cholesterol-lowering drugs, statins. Previous studies have demonstrated that the enzyme activity is regulated by sterol-induced degradation in addition to transcriptional regulation through sterol-regulatory-element-binding proteins (SREBPs). While 25-hydroxycholesterol induces both HMGCR degradation and SREBP inhibition in a nonselective manner, lanosterol selectively induces HMGCR degradation. Here, to clarify the structural determinants of selectivity for the two activities, we established a luciferase-based assay monitoring HMGCR degradation and used it to profile the structure-activity/selectivity relationships of oxysterols and (oxy)lanosterols. We identified several sterols that selectively induce HMGCR degradation and one sterol, 25-hydroxycholest-4-en-3-one, that selectively inhibits the SREBP pathway. These results should be helpful in designing more potent and selective HMGCR degraders.

Keywords: Degradation; HMG-CoA reductase; Lanosterols; Luciferase; Oxysterols; SREBP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • HEK293 Cells
  • Humans
  • Hydroxymethylglutaryl CoA Reductases / metabolism*
  • Lanosterol / metabolism*
  • Lanosterol / pharmacology
  • Molecular Structure
  • Oxysterols / metabolism*
  • Oxysterols / pharmacology
  • Sterol Regulatory Element Binding Proteins / antagonists & inhibitors
  • Sterol Regulatory Element Binding Proteins / metabolism
  • Structure-Activity Relationship

Substances

  • Oxysterols
  • Sterol Regulatory Element Binding Proteins
  • Lanosterol
  • HMGCR protein, human
  • Hydroxymethylglutaryl CoA Reductases