24/09/2025
🚨 Scientists found a way to reverse stroke damage — using stem cells that regenerate brain tissue and restore movement.
Scientists at the University of Zurich have achieved a major breakthrough in stroke recovery, showing that neural stem cell transplants can regenerate brain tissue, restore motor function, and even repair blood vessels in mice.
Stroke, which affects one in four adults globally, often leaves lasting damage such as paralysis or speech loss because brain cells destroyed by oxygen deprivation cannot naturally regenerate. But in this study, human neural stem cells—derived from induced pluripotent stem cells—were transplanted into the brains of stroke-injured mice. Within weeks, many of the transplanted cells matured into functioning neurons that communicated with existing brain cells, while also reducing inflammation and strengthening the blood-brain barrier.
The transplanted mice not only showed brain repair at the cellular level but also reversed motor impairments, as proven through AI-assisted gait analysis. Importantly, researchers discovered that the therapy was most effective when administered one week after a stroke, offering a practical time window for future clinical use. While more work is needed to ensure safety—such as preventing uncontrolled cell growth—the team is developing methods for less invasive delivery, like endovascular injection. With human clinical trials already underway in Japan using similar stem cell techniques for Parkinson’s disease, scientists believe that stroke could soon be the next frontier for regenerative medicine.
Source: Weber, R. Z., Achón Buil, B., Rentsch, N. H., et al. (2025). Neural xenografts contribute to long-term recovery in stroke via molecular graft-host crosstalk. Nature Communications, September 16, 2025. University of Zurich.