There is evidence that abnormal concentrations of positively-charged metal ions (eg, copper, iron, and zinc) interact with beta-amyloid in the brain during the development of Alzheimer’s disease. Therefore, correcting these abnormal levels might help people with this disease. (The photo shows yellow amyloid plaque surrounded by black neurofibrillary tangles.)

One option for treatment is chelation.

Chelation therapy is the process by which positively-charged metal ions are captured and then removed from the body by a large chelating molecule.

In practice chelation has not been very effective. There are side effects, and older chelation agents have difficulty getting to brain cells (ie, crossing the blood-brain barrier). But now, preliminary evidence suggests that nanotechnology might overcome these problems.

In the lab, nanoparticles have been used to transport chelators and chelator-metal complexes in both directions across the blood-brain barrier. Further research will be needed to prove it is a safer and more effective treatment in Alzheimer’s disease — and in other neurological diseases.

Illustration: Neurofibrillary tangles and fiberlike processes of neurons (black) surround an amyloid plaque. Source: Chemical and Engineering News

8/28/06 18:44 JR