Nanoparticle iron chelators: a new therapeutic approach in Alzheimer disease and other neurologic disorders associated with trace metal imbalance

Neurosci Lett. 2006 Oct 9;406(3):189-93. doi: 10.1016/j.neulet.2006.07.020. Epub 2006 Aug 21.

Abstract

Accumulating evidence suggests that oxidative stress may be a major etiologic factor in initiating and promoting neurodegeneration in Alzheimer disease. Contributing to this, there is a dyshomeostasis of metal ions in Alzheimer disease with abnormally high levels of redox-active metals, particularly iron, in affected areas of the brain. Although it is unclear whether metal excesses are the sole cause of oxidative stress and neurodegeneration or a by-product of neuronal loss, the finding that metal chelators can partially solubilize amyloid-beta deposits in Alzheimer disease suggests a promising therapeutic role for chelating agents. However, the blood-brain barrier and toxicity of known chelators limit their utility. In this study, we suggest that covalent conjugation of iron chelators with nanoparticles may help overcome the limitations in blood-brain barrier permeability of existing chelation therapy. Using in vitro studies, we have shown that a chelator-nanoparticle system and the chelator-nanoparticle system complexed with iron, when incubated with human plasma, preferentially adsorb apolipoprotein E and apolipoprotein A-I, that would facilitate transport into and out of the brain via mechanisms used for transporting low-density lipoprotein. Our studies suggest a unique approach, utilizing nanoparticles, to transport chelators and chelator-metal complexes in both directions across the blood-brain barrier, thus providing safer and more effective chelation treatment in Alzheimer disease and other neurodegenerative diseases.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged, 80 and over
  • Alzheimer Disease / pathology*
  • Apolipoprotein A-I / metabolism
  • Apolipoproteins E / metabolism
  • Brain / drug effects*
  • Electrophoresis, Gel, Two-Dimensional / methods
  • Humans
  • In Vitro Techniques
  • Iron / metabolism*
  • Iron Chelating Agents / chemistry
  • Iron Chelating Agents / pharmacology*
  • Nanostructures*
  • Pyridones / chemistry
  • Pyridones / pharmacology*

Substances

  • Apolipoprotein A-I
  • Apolipoproteins E
  • Iron Chelating Agents
  • Pyridones
  • 3-hydroxy-4-pyridone
  • Iron