The diagnosis of dementia is often made far too late – the chances of effective treatment are then slim. Researchers now want to develop a simple blood test for practical use.
Researchers have found molecules in the blood that could indicate impending dementia. The procedure is not yet practicable. The aim is to develop a simple blood test in order to be able to assess the risk of dementia in routine medical practice. According to the study data, microRNAs could potentially also be targets for dementia therapy.
Scientists from the German Center for Neurodegenerative Diseases eV (DZNE) and the University Medical Center Göttingen (UMG) were involved in the study. Your results, which you will find in the specialist journal EMBO Molecular Medicine imagine relying on human and laboratory studies. The biomarker described by a team led by Prof. André Fischer is based on measuring the concentration of so-called microRNAs.
“Diagnosis much too late”
“When symptoms of dementia become noticeable, the brain is already massively damaged. The diagnosis is currently far too late to even have a chance of effective treatment. If dementia is detected early, the chances of positively influencing the course of the disease increase, ”says André Fischer, research group leader and spokesman at the DZNE site in Göttingen and professor at the UMG’s Clinic for Psychiatry and Psychotherapy.
“We need tests that ideally respond when dementia has not yet broken out and reliably assess the risk of a later disease. So they warn early on. We are confident that our current study results will pave the way for such tests. “
Read mental fitness on microRNAs
The biomarker that Fischer and his colleagues found is based on the measurement of microRNAs in the blood. MicroRNAs are molecules with a regulatory effect: They influence the production of proteins and thus a central process in the metabolism of every living being. “We wanted to find out whether there are special microRNAs whose occurrence in the blood correlates with mental fitness,” says Fischer.
Through extensive studies on humans, mice and cell cultures, the researchers were ultimately able to identify three microRNAs whose concentration is related to mental performance. To do this, they analyzed data from both young, cognitively inconspicuous people and data from older people with MCI (mild cognitive disorders). For the data from healthy people, the Göttingen scientists cooperated with the LMU Munich Clinic. The data from MCI sufferers came from a study by the DZNE that has been going on for years and in which university clinics nationwide are involved.
Harbingers of dementia
Ultimately, the various findings came together like pieces of a puzzle: in healthy people, the concentration of microRNAs correlated with mental fitness. The lower the blood count, the better the test subjects performed in the cognition tests. In mice, on the other hand, this value rose even before the animals deteriorated mentally – whether due to age or because they developed symptoms similar to those of Alzheimer’s disease.
Further evidence came from patients with MCI: Of those in whom the blood marker was greatly increased, around 90 percent developed Alzheimer’s disease within two years. “We therefore see an increased blood level of these three microRNAs as a harbinger of dementia,” says Fischer. “We estimate that this biomarker indicates a development in humans that is around two to five years in the future.”
Any goals for therapy
In their studies on mice and cell cultures, the researchers also found that the three identified microRNAs influence inflammatory processes in the brain and “neuroplasticity” – this includes the ability of nerve cells to connect to one another. This suggests that the three microRNAs are more than warning signals.
“In our opinion, they are not just markers, but also have an active effect on pathological processes. That makes them possible starting points for therapy, ”says Fischer. “In fact, we see that the learning ability of mice improves when these microRNAs are blocked by pharmaceuticals. We have observed this both in mice with age-related mental deficits and in mice with brain damage, as occurs in a similar way in Alzheimer’s disease. “
Use in practice
The newly found indicator still has to be checked further, and the current measurement method is too complex for practical use: “In future studies, we want to clinically validate this biomarker. We would also like to develop a simple test procedure, ”says Fischer. “Our goal is a cost-effective test, similar to the rapid test for SARS-CoV-2 with the difference that you would need a drop of blood for our purposes.
Such a test could be used in routine medical examinations in order to detect an increased risk of dementia at an early stage. People for whom the results are conspicuous could then undergo more complex diagnostics. “
This post is based on one Press release of the German Center for Neurodegenerative Diseases eV (DZNE). We have the corresponding original publication here and linked in the text for you.
Image source: Solen Feyissa, unsplash