A liver enzyme released during exercise has recently been shown to repair aging brain blood vessels and restore memory in mice.
The new finding reframes how physical activity protects cognition by tracing its benefits to a repair process at the brain’s outer boundary rather than inside neurons themselves.
Leaky vessels linked to aging
In older mice, the blood vessels that seal the brain from the bloodstream had become porous, allowing small molecules to escape into surrounding tissue.
By tracking those leaks in aging animals, Dr. Saul Villeda at the University of California, San Francisco (UCSF) demonstrated that a surge of the liver enzyme GPLD1 coincided with tighter vessel walls and stronger memory performance.
Instead of entering brain tissue, the enzyme acted on the vessel surface, trimming away a buildup…