Is lithium a new treatment for Alzheimer’s disease?
Experiments reported in 2002 and 2003 showed that lithium inhibits an enzyme, glycogen synthase kinase. Researchers hypothesized that this action of lithium might reduce accumulation of beta amyloid and also block formation of neurofibrillary tangles by tau protein. Consistent with this hypothesis, experiments in cultured brain cells and in special transgenic mice have demonstrated that lithium reduces amyloid beta prodcution in these experimental models of Alzheimer’s Disease. Whether this property of lithium could translate into functional improvement in human victims of Alzheimer’s Disease remains uncertain, but a 2007 transgenic mouse study (Caccamo et al. Am J Pathol 2007;170:1669-75) found lithium to reduce tau phosphorylation but not A beta or working memory deficits, and a single blind human study reported byHampel and colleagues in the Journal of Clinical Psychiatry (2009;70:922-31) found no treatment effect of lithium (at target blood levels from 0.5 – 0.8 meq/l during the 10
