Both d- and l-Glucose Polyphosphates Mimic d- myo-Inositol 1,4,5-Trisphosphate: New Synthetic Agonists and Partial Agonists at the Ins(1,4,5)P3 Receptor

J Med Chem. 2020 May 28;63(10):5442-5457. doi: 10.1021/acs.jmedchem.0c00215. Epub 2020 May 6.

Abstract

Chiral sugar derivatives are potential cyclitol surrogates of the Ca2+-mobilizing intracellular messenger d-myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P3]. Six novel polyphosphorylated analogues derived from both d- and l-glucose were synthesized. Binding to Ins(1,4,5)P3 receptors [Ins(1,4,5)P3R] and the ability to release Ca2+ from intracellular stores via type 1 Ins(1,4,5)P3Rs were investigated. β-d-Glucopyranosyl 1,3,4-tris-phosphate, with similar phosphate regiochemistry and stereochemistry to Ins(1,4,5)P3, and α-d-glucopyranosyl 1,3,4-tris-phosphate are full agonists, being equipotent and 23-fold less potent than Ins(1,4,5)P3, respectively, in Ca2+-release assays and similar to Ins(1,4,5)P3 and 15-fold weaker in binding assays. They can be viewed as truncated analogues of adenophostin A and refine understanding of structure-activity relationships for this Ins(1,4,5)P3R agonist. l-Glucose-derived ligands, methyl α-l-glucopyranoside 2,3,6-trisphosphate and methyl α-l-glucopyranoside 2,4,6-trisphosphate, are also active, while their corresponding d-enantiomers, methyl α-d-glucopyranoside 2,3,6-trisphosphate and methyl α-d-glucopyranoside 2,4,6-trisphosphate, are inactive. Interestingly, both l-glucose-derived ligands are partial agonists: they are among the least efficacious agonists of Ins(1,4,5)P3R yet identified, providing new leads for antagonist development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dose-Response Relationship, Drug
  • Drug Partial Agonism*
  • Glucose / chemistry*
  • Glucose / pharmacology
  • HEK293 Cells
  • Humans
  • Inositol 1,4,5-Trisphosphate / chemistry*
  • Inositol 1,4,5-Trisphosphate / pharmacology
  • Inositol 1,4,5-Trisphosphate Receptors / agonists*
  • Inositol 1,4,5-Trisphosphate Receptors / chemistry*
  • Molecular Docking Simulation / methods
  • Molecular Mimicry / drug effects*
  • Molecular Mimicry / physiology
  • Polyphosphates / chemistry*
  • Polyphosphates / pharmacology
  • Protein Structure, Secondary
  • Rats
  • Rats, Wistar

Substances

  • Inositol 1,4,5-Trisphosphate Receptors
  • Itpr3 protein, rat
  • Polyphosphates
  • Inositol 1,4,5-Trisphosphate
  • Glucose