Adult brain repairs itself via moving cell nuclei, study finds

The adult brain can repair itself after injury or certain autoimmune diseases because support cells send newly formed cell nuclei into damaged areas, according to a University of Zurich mouse study reported on August 12, 2026.

That finding challenges the long-held assumption that the adult brain cannot fully replace destroyed astrocytes. Astrocytes are star-shaped glial cells that nourish neurons, regulate blood flow and maintain brain tissue health.

Astrocyte loss occurs after brain injuries and in autoimmune diseases such as neuromyelitis optica spectrum disorder, where antibodies attack these cells.

Co-lead authors Marina Herwerth and Matthias Wyss, working under Bruno Weber at the Institute of Pharmacology and Toxicology, identified a population of regenerative astrocytes in living mice. These cells gather around damaged regions and rebuild the lost astrocyte network.

Using two-photon microscopy, the team observed mouse brains in real time for several weeks and tracked gene activity in different regions. The regenerative astrocytes divide, and their daughter-cell nuclei glide across long distances through cell extensions to repopulate injured tissue.

Bruno Weber said the findings reveal a previously unknown self-repair ability in the adult brain and point toward new ways to support recovery from ailments involving astrocyte loss.

The researchers also identified many genes and signaling pathways temporarily activated during repair. If selectively activated, these mechanisms could help restore damaged brain tissue and improve recovery from certain brain disorders.