Alzheimer's disease: an intracellular movement disorder?

Axonal transport is essential for maintaining the structure and function of nerve cells. Deficient axonal transport has been implicated in several neurodegenerative diseases, including Alzheimer's disease (AD). In addition to a disturbed cytoskeleton and other abnormalities observed in AD that are suggestive of axonal transport deficits, several AD-related proteins are implicated in the regulation of axonal transport. A recent study has demonstrated that the axonal transport deficit occurs early in the course of AD, preceding amyloid pathology substantially in mouse models of AD; more importantly, the study showed that reduced axonal transport leads to increased amyloid beta production and deposition. These data place axonal transport deficits at a central point in the pathogenesis of AD.