Dementia: microRNAs indicate a risk of mental degradation
More and more people are suffering from dementia. There is currently no cure for the disease, but the right treatment can delay its course. Those affected can remain independent the earlier the disease is diagnosed. In the future, new findings from researchers in Germany may also help with early detection. They found warning signs of dementia in the blood.
According to experts, around 1.6 million people in Germany live with dementia. Most of them are affected by Alzheimer’s disease. The course of the disease can be positively influenced by various drugs and non-drug treatments – but it cannot be stopped or cured. A diagnosis as early as possible is important in order to sound out the therapeutic options. A blood test could also help in the future.
Measurement of the concentration of microRNAs
Researchers from the German Center for Neurodegenerative Diseases eV (DZNE) and the University Medical Center Göttingen (UMG) have tracked down molecules in the blood that could indicate impending dementia.
Their findings, which were published in the specialist journal “EMBO Molecular Medicine”, are based on studies on humans and on laboratory studies. Several university hospitals nationwide were also involved in the investigations.
As stated in a press release, the biomarker described by a team led by Prof. André Fischer is based on measuring the concentration of so-called microRNAs.
The procedure is not yet practicable; The aim of the researchers is therefore 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.
If the symptoms are noticeable, the brain is already damaged
“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 spokesperson 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. “
The biomarker that the scientists found is based on the measurement of so-called microRNAs in the blood. As explained in the communication, 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.
“There are many different microRNAs and each of them can regulate entire networks of interdependent proteins and thus influence complex processes in the organism. MicroRNAs therefore have a broad effect. We wanted to find out whether there are special microRNAs whose occurrence in the blood correlates with mental fitness, ”explains 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” – the abbreviation stands for mild cognitive disorders. For the data from healthy people, the Göttingen researchers cooperated with the LMU Munich Clinic.
The data of MCI sufferers came from a study by the DZNE that has been going on for years and in which university hospitals nationwide are involved.
Harbinger of dementia
According to the experts, the concentration of microRNAs correlated with mental fitness in healthy people. The lower the blood count, the better the test subjects did 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 those affected by 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.”
More than warning signs
In addition, the researchers found in their studies on mice and cell cultures 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. “
Recognize increased risk of dementia at an early stage
The newly found indicator 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, ”explains 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,” said the expert.
“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. “(Ad)
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This text complies with the requirements of specialist medical literature, medical guidelines and current studies and has been checked by medical professionals.
This article is for general guidance only and is not intended to be used for self-diagnosis or self-treatment. He can not substitute a visit at the doctor.