New research from the Institute of Psychiatry, Psychology and Neuroscience at King’s College London showed that a blood-based test developed by its scientists could detect Alzheimer’s disease three and a half years before a clinical diagnosis, predicting the risk of the condition.
The research, whose results published in the journal Brain could help scientists understand changes the brain goes through at the earliest stages of Alzheimer’s, supports the idea that the formation of new brain cells can be influenced by components in human blood through a process called neurogenesis, which occurs in the hippocampus- part of the brain is involved in learning and memory.
Previous studies have only been able to study neurogenesis through post-mortem examinations – in its later stages – while Alzheimer’s affects the new brain cells’ formation in the hippocampus during the early stages of the disease.
Focused on understanding the early changes in the brain during neurogenesis, the researchers used blood samples collected over a number of years from 56 people that have begun to experience a weakening of their memory or cognitive ability, a condition known as mild cognitive impairment (MCI).
People suffering from this condition progress to Alzheimer’s disease diagnosis at a much higher rate than the wider population although not everyone with MCI will develop the disease.
By using only blood samples collected furthest away from when someone had Alzheimer’s disease diagnosed, researchers found that the changes in neurogenesis occurred 3.5 years before a clinical diagnosis of the disease.
Per Dr. Edina Silajdzic, the study’s joint first author, the study results are potentially allowing them to predict the onset of Alzheimer’s early in a non-invasive fashion, complementing other blood-based biomarkers that reflect the classical signs of the disease, such as the accumulation of amyloid and tau – the ‘flagship’ proteins of Alzheimer’s disease.
In the study, 36 of the 56 people were later diagnosed with Alzheimer’s. The research further showed that their blood samples promoted a decrease in cell growth and division as well as an increase in the process by which cells are programmed to die- apoptotic cell death.
The researchers believe that it may be an early compensating mechanism for the brain cells loss experienced by people developing Alzheimer’s disease although the reasons for the increased neurogenesis remain unclear.
Prof Sandrine Thuret, the study’s lead author from the institute, said that they aimed to use this model to understand neurogenesis and to use changes in this process to predict Alzheimer’s disease, noting that they’ve found the first evidence that the body’s circulatory system in humans can have an effect on the brain’s ability to form new cells.
Be the first to comment