The adult human brain has limited capacity to repair or regenerate neurons lost to Alzheimer’s disease, the most common type of dementia. Existing treatments can slow disease progression but do not reverse cognitive decline. In a study publishing in the Cell Press journal Cell Biomaterials on August 26, researchers show that engineered nanoparticles can not only regenerate neurons in human brain organoids but also restore neural circuits and improve cognition in mice.

The new neurons can become mature and survive. We also confirmed much higher neuron density in the brains of treated mice.