Characterization of radioiodinated ligand binding to amyloid beta plaques

J Mol Neurosci. 2003;20(3):249-54. doi: 10.1385/JMN:20:3:249.

Abstract

Several novel series of iodinated compounds based on the thioflavin backbone structure have been developed and characterized. These iodinated compounds showed high specific binding to amyloid beta (Abeta) aggregates with subnanomolar to nanomolar affinities. Probes like IMPY and MIPA display high brain uptakes and fast washout in normal mice, resulting in low background signals (presumably no amyloid plaques present in normal mouse brain), whereas TZDM shows long brain retention in normal mice suggesting high nonspecific in vivo binding. It is likely that tracers, that is, IMPY or MIPA, with desirable in vivo properties, will provide the highest target to non-target ratio; therefore, they are most likely to be successful as imaging agents targeting Abeta plaques in the brain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alzheimer Disease / diagnostic imaging*
  • Alzheimer Disease / metabolism
  • Alzheimer Disease / pathology
  • Amyloid beta-Peptides / drug effects
  • Amyloid beta-Peptides / metabolism
  • Animals
  • Benzothiazoles
  • Binding Sites / drug effects
  • Binding Sites / physiology
  • Binding, Competitive / physiology
  • Brain / diagnostic imaging*
  • Brain / metabolism
  • Brain / pathology
  • Humans
  • Iodine Radioisotopes* / metabolism
  • Ligands
  • Male
  • Mice
  • Mice, Inbred ICR
  • Peptide Fragments / drug effects
  • Peptide Fragments / metabolism
  • Plaque, Amyloid / diagnostic imaging*
  • Plaque, Amyloid / pathology
  • Pyrazoles* / metabolism
  • Pyridines / metabolism
  • Thiazoles* / metabolism
  • Tomography, Emission-Computed, Single-Photon

Substances

  • 2-(4'-dimethylaminophenyl)-6-iodobenzothiazole
  • 6-iodo-2-(4'-dimethylamino-)phenyl-imidazo(1,2-a)pyridine
  • Amyloid beta-Peptides
  • Benzothiazoles
  • Iodine Radioisotopes
  • Ligands
  • MIPA compound
  • Peptide Fragments
  • Pyrazoles
  • Pyridines
  • Thiazoles
  • amyloid beta-protein (1-40)
  • thioflavin T