TOMSK, Feb 18 – RIA Tomsk.
Scientists of Tomsk State University (TSU) conducted a study, the
results of which may become the basis for a new method for diagnosing
the consequences of ischemic stroke and further treatment, the
university's website reported on Thursday.
Earlier it was
reported that TSU scientists, together with colleagues from Belgium and
the United States, have created a non-invasive tool for tracking young
neurons in the brain. The development cannot be used on humans, but it
allows one to evaluate in laboratory animals how the brain recovers
after a stroke, which will help create new methods of treating people.
It
was also reported that TSU neuroscientists received a grant from the
Russian Science Foundation (RSF) and were the first in the world to
trace the death and restoration of nerve cells and axons after a
cerebral stroke. The study was carried out on laboratory animals using a
new diagnostic technology developed by them.
"Scientists
in the course of experiments conducted using a model of ischemic stroke
in rats have obtained new data on the processes that occur in the focus
of brain damage. This information could form the basis of a noninvasive
diagnostic method for assessing the degree of inflammation, predicting
the course of the disease and choosing treatment strategies", – is said
in the report.
It is added that the research results were published in the highly rated International Journal of Molecular Sciences.
How did the new study take place
© с сайта Томского госуниверситета
The
aim of the research was to study the process of the formation of new
neurons in ischemic stroke. For this, a special method of labeling young
neurons was created. TSU scientists together with colleagues from the
University of Leuven (Belgium) designed a "courier" for transporting
genetic material into brain cells – special vectors based on
lentiviruses and adeno-associated viruses
"Genetic
engineers inserted into the deactivated virus a ferritin protein gene
and a special genetic sequence that allows increasing the production of
ferritin only in young neurons. Young neurons that have accumulated
ferritin containing iron atoms can be "seen" using a special MRI
protocol", – the press service reported.
According to the
head of the Laboratory for Neurobiology of the TSU Biological Institute
Marina Khodanovich, when scanning the brains of animals in which
ischemic stroke was simulated, scientists saw two areas with a specific
change in the MRI signal, indicating the presence of a large number of
cells containing ferritin.
"The signal was recorded in a
nonischemic zone, where, after a stroke, the active production of young
neurons usually begins. This was not a surprise, but the presence of the
same signal in the focus of the stroke was unexpected", – Khodanovich
is quoted in the message.
© сайт Томского госуниверситета
Subsequent examination of brain
slices showed that such a signal was given by macrophages - cells of the
immune system, also called "big eaters". Macrophages are capable of
actively trapping and digesting bacteria, particles foreign or toxic to
the body, and fragments of dead cells.
"After a cerebral
stroke, macrophages migrate to the ischemic focus, where they absorb not
only the destroyed nerve tissue, but also iron-rich erythrocytes,
thereby becoming "visible" on MRI", – explains the message.
How the study can help patients
According
to TSU neurobiologists, surveillance over macrophage clusters using MRI
can be used to create a new diagnostic approach that will be useful to
clinicians. The technology will make it possible to assess the intensity
of inflammation in the stroke focus, obtain more information about the
patient's condition, more accurately predict the course of the disease,
and select drug therapy.
"The task that neuroscientists
need to solve is to find a way to distinguish between signals from
macrophages and new neurons with genetic marks. To do this, it is
necessary to continue the research that has begun. If the RSF grant is
extended, the TSU scientists' research will focus on these very tasks", –
summarizes the press service.