Tracking Alzheimer's brain alterations in living mice

A team based in the UK and Italy has developed a method to monitor a key brain alteration found in Alzheimer’s disease in the brain of living, freely moving mice using optic fibres. 

Alzheimer's disease is marked by the buildup of amyloid plaques in the brain. Until now, most ways of studying these deposits required directly observing the brain tissue. Researchers at the University of Strathclyde, UK, and the Italian Institute of Technology implanted a device with tapered optical fibres into living mice to capture light from the brain. By injecting mice with a dye that goes into the brain and turns amyloid plaques fluorescent, the researchers observed fluorescence only in mice genetically altered to show Alzheimer’s symptoms and not in healthy animals. The intensity of the fluorescent light increased with age, which is consistent with disease progression.  

While this approach, published in Neurophotonics, cannot distinguish individual plaques, it reveals fluorescent levels in different depths of the brain, allowing scientists to track changes long-term in deep brain regions and opening the door to study how treatments affect disease progression.