The Brain Possesses More Self-Healing Power Than Previously Thought

After injuries or certain autoimmune diseases, the brain appears to be able to regenerate better than previously thought. Researchers at the University of Zurich have shown in a mouse model that special support and supply cells repopulate damaged brain regions by initially migrating only the newly formed cell nuclei there.

Glial cells are the support and supply cells in the brain. The star-shaped representatives of these cells – called astrocytes – are essential for the functioning of neurons. They supply nerve cells with nutrients, help regulate blood flow, and keep brain tissue healthy. For a long time, it was assumed that the adult brain could not completely replace lost astrocytes, for example, in cases of brain injuries or autoimmune diseases such as the rare neuromyelitis optica spectrum disorder, in which the body's own antibodies destroy these cells.

Now, a new study by co-first authors Marina Herwerth and Matthias Wyss from the Institute of Pharmacology and Toxicology at the University of Zurich (UZH) refutes this assumption: The team, led by Bruno Weber, discovered a specialized group of "regenerative" astrocytes in the brains of living mice. These astrocytes are responsible for cell regeneration at the periphery of damaged brain regions. "Our results reveal a previously unknown self-healing capacity of the adult brain. They point to new ways to support recovery in diseases involving astrocyte loss," says Weber.

To achieve this, the researchers observed and mapped living mouse brains in real time over several weeks using two-photon microscopy, identifying which genes were active in which regions. In this way, they identified the specific astrocytes responsible for rebuilding the injured tissue. But these cells don't just divide; they perform a remarkable feat: "The newly formed nuclei of the daughter cells glide over long distances to repopulate the damaged brain region and reconnect the astrocyte network," says Weber.

The discovery of how the nuclei of adult brain cells migrate to injured tissue via the long, star-shaped processes of astrocytes expands our understanding of how the brain self-organizes and regenerates after certain injuries. If these mechanisms could be specifically activated, it could help to better repair damaged brain tissue, restore astrocyte networks, and thus improve recovery after certain brain diseases.

(Newswise/HG)