Scientists have uncovered two new approaches to blocking the progression of Alzheimer's disease. The two separate studies, one from a Belgian group of researchers from the Catholic University of Leuven and published in the journal Science and the other from an NIH team in Bethesda, US and published in PNAS, focus on the mechanism by which a protein called beta amyloid, which builds up in the brains of Alzheimer's patients, is formed and how it harms cells.
In the Science paper Amantha Thathiah and colleagues used a genetic technique to look for chemical messengers that, when added to cells, increased beta amyloid production. Using this approach they were able to home in on a signalling molecule called G protein-coupled receptor 3 (GPR-3), which turns on an enzyme called gamma-secretase, which in turn produces beta amyloid. As the team expected, turning off the molecule reduced beta-amyloid production whilst boosting its levels increased beta-amyloid. Encouragingly, GPR-3 is only expressed in the brain, which means it might be possible to engineer a drug designed to target selectively this receptor, thus minimising the side effects, which have plagued earlier anti-Alzheimer's drug strategies.