With the exception of beta and gamma secretases and amyloid beta peptides, targets for Alzheimer's disease are few and far between. Last week, researchers at Harvard Medical School added to the list an enzyme called Acyl-coenzyme A cholesterol acyltransferase (ACAT), which is involved in regulating cholesteryl ester levels in the cell.

Writing in Nature Cell Biology, the researchers showed in CHO cells that the balance between free cholesterol and cholesteryl esters affects the production of amyloid-beta, a peptide that has been implicated in increasing the risk of developing AD. In particular, they found that elevated intracellular levels of cholesteryl esters led to increased amyloid beta generation.