Brain of rats who suffered a stroke, managed to "fix"

Anna Stavina, XX2 century, based on the materials of Lund University: Transplanted neurons incorporated into a stroke-injured rat brain

Nowadays, a stroke, as a rule, leads to a permanent loss of any body functions. But in the future, the brain damaged by a stroke can be "repaired" by replacing the dead cells with new healthy neurons with the help of transplantation. Researchers have already taken a step in this direction. During the experiment, they implanted neurons into the brains of rats who had suffered a stroke. Some of the transplanted cells successfully took root, as evidenced by the restoration of an adequate response to touching the tip of the nose or paw.

For the work, scientists used human skin cells. They were "reprogrammed", after which they returned to the stem cell stage and matured again – but already as neurons, normally found in the cerebral cortex.

A few years ago, a group of researchers from the Stem Cell Center of Lund University Medical University has already demonstrated that transplantation of this type of cells into the cerebral cortex of rats who had a stroke led to an improvement in the motor functions of animals. However, until now it was not reliably known whether the recipient's brain actually used the transplanted cells to form working connections. A new study has shown that yes.

In the course of the work, the scientists used various modern techniques: electron microscopy, virus-based tracking techniques, registration of the activity of transplanted cells and optogenetics. The latter is a technique for studying the work of nerve cells based on the introduction of special channels into their membrane – opsins that react to light excitation. The results of the experiments demonstrated that different parts of the brain form normally functioning connections using transplanted neurons. Later, a change in activity was recorded in these neurons in response to touching the tip of the nose or paw of the animal.

"Some of the transplanted neurons received signals from the recipient's brain in the usual way. This means that they have integrated into the brain damaged by a stroke and were able to replace some of the dead cells," says Zaal Kokaia, professor at the Stem Cell Center.

Of course, a laboratory animal with a stroke model is not the same as a patient who has suffered a stroke. But Olle Lindvall, a member of the research group, professor and consultant physician, considers the work done an important first step. She demonstrated the fundamental possibility of replacing neurons that died as a result of a stroke with new healthy cells.

"This is a fundamental study, and it is not yet possible to say when we will be ready to work with patients. But the goal is clear: to develop a treatment method that can "repair" the brain damaged by a stroke. Currently, there are no effective approaches that would allow you to restore lost functions if the stroke occurred more than a few hours ago," explains Kokaya.

Article by Tornero et al. Synaptic inputs from stroke-injured brain to grafted human stem cell-derived neurons activated by sensory stimuli is published in the journal Brain.

Portal "Eternal youth" http://vechnayamolodost.ru  25.01.2017