A new type of imaging technology could be instrumental in the understanding and treatment of Alzheimer’s disease. Positron emission tomography (PET) can be used to see the widespread loss of synapses in the brain, even when the condition is in its early stages.
Scientists at Yale University in the US were able to look at the density of synapses in those with early stage Alzheimer’s and compare them with healthy individuals. Brain synapses are the structures that transmit signals between cells and are therefore important in cognition.
Following the hypothesis, it was found that synapse loss was particularly high in areas close to the hippocampus. There were also detectable losses of synapses in other parts of the brain, but the PET technique helped to form a clearer picture.
Adam Mecca, assistant professor of psychiatry and first author of the paper, said: "This gives us confidence that we may use these results as a biomarker outcome for therapeutic trials, which could help speed development of new drugs to combat the disease."
What the PET tool does is provide imaging of a protein that is found in nearly all brain synapses. Whereas there had been technologies previously that could show brain tissue loss or reduced brain metabolism, the results could only be seen in broad strokes and not the specific distribution.
Christopher van Dyck, professor of psychiatry, neurology, and neuroscience, and senior author of the study, said: "These methods will allow us to examine synaptic loss at still earlier stages of disease - when people have evidence of Alzheimer's pathogenesis but have not yet manifested symptoms."
This research can be taken further, as the team at Yale have been given a grant to carry out more synaptic imaging. They will then be able to relate synaptic loss to other Alzheimer’s disease markers in order to form a wider picture. These include accumulations of amyloid and tau proteins, which have previously been identified as important factors in the progression of the condition.
It’s vital that more is understood about the early stages of Alzheimer’s, as scientists have found it’s difficult to treat the disease once it’s taken hold. Most treatments focus on slowing its progression, as there is not yet a cure.
Each new piece of research provides another piece of the puzzle, allowing experts to build upon the knowledge bank surrounding Alzheimer’s. Hundreds of scientists throughout the world are working in the field, as it’s a problem that is affecting people in every corner of the planet. There are varying approaches to developing treatments and a cure, with each group of researchers choosing which line of enquiry to follow.
At present, around 850,000 people in the UK are suffering with dementia and Alzheimer’s is the most common form of the disease. It’s expected that this figure will rise to 1.6 million by the year 2040, unless more effective treatments can be developed and successfully brought to market.