A major hurdle in drug development for Alzheimer’s disease (AD) is that treatment must be started early in the disease.
That is, before irreversible neurodegeneration occurs. Therefore, biomarkers with good predictive value are important to select relevant populations for early interventions against AD.
That is why the discovery by the group at the Karolinska Institutet in Sweden of a type of blood sugar molecule associated with the level of tau, a protein that plays a critical role in the development of severe dementia, could be key.
The study, published in Alzheimer’s & Dementia, may pave the way for a simple screening procedure, capable of predicting onset ten years in advance.
Robin Zhou, a medical student and research affiliate at Karolinska Institutet’s Department of Neurobiology, Care Sciences and Society (NVS), explained, “The role of glycans, structures made up of sugar molecules, is a relatively unexplored field of research. of dementia.
We demonstrate in our study that glycan blood levels are altered early during the development of the disease.
This could mean that we will be able to predict the risk of its occurrence with just a blood test and a memory test.”
In Alzheimer’s disease, neurons in the brain die, which is thought to be the result of the abnormal buildup of amyloid beta and tau proteins.
Clinical trials of Alzheimer’s drugs show that treatment must begin early in the disease process, before too many neurons die, in order to reverse the process before it is too late.
There is a need for non-invasive detection methods for Alzheimer’s disease.
Blood markers are preferable as cerebrospinal fluid sampling is more difficult and brain imaging is expensive.
The Karolinska Institutet team is on that path, which previously demonstrated a link between tau protein and glucan levels in people with the disease, but these analyzes were performed on cerebrospinal fluid.
By measuring glycan levels in the blood, we found that people with matching glycan and tau levels were more than twice as likely to develop Alzheimer’s dementia. We also show that a simple statistical model, taking into account blood glucan and tau levels, the APOE4 risk gene, and a memory test, can be used to predict disease with 80% confidence nearly a decade before symptoms such as memory loss appear.
The results are based on 233 participants from the Swedish National Study on Aging and Care on Kungsholmen (SNAC-K).
The samples were collected between 2001 and 2004, and the participants were regularly monitored for factors such as memory loss and the presence of dementia.
The follow-ups were carried out every three or six years and lasted for 17 seasons.
Now, in addition, blood samples from the remaining participants in the SNAC-K study, as well as other studies on aging inside and outside Sweden, will be analyzed.
We are collaborating with primary care researchers in Sweden to assess different dementia biomarkers in primary health care settings.
We hope that blood glycans will prove to be a valuable adjunct to current methods of detecting disease early.