Converting cells into new neurons could lead to a pill that repairs brain damage

As powerful as the human brain is, once it's damaged it can't really recover completely. Now researchers at Penn State may have found a way to boost the brain's regenerative abilities, using certain molecules to convert neighboring cells into new neurons. The technique could eventually lead to pills that treat brain injuries, stroke or Alzheimer's disease.

Most cells in the body can patch up damage by dividing to create new versions of themselves. But neurons lack this ability, so once they're damaged through illness or injury, there's not much that can be done. Worse still, in an overzealous attempt to protect the injured site, glial cells form scar tissue around damaged brain regions, which can reduce what little neuron growth there might be and prevent neurons from effectively communicating with each other.

With the new work, the Penn State team found that these glial cells could be put to work rebuilding the damage, rather than just getting in the way.

"The biggest problem for brain repair is that neurons don't regenerate after brain damage, because they don't divide," says Gong Chen, lead researcher on the study. "In contrast, glial cells, which gather around damaged brain tissue, can proliferate after brain injury. I believe turning glial cells that are the neighbors of dead neurons into new neurons is the best way to restore lost neuronal functions."

"We identified the most efficient chemical formula among the hundreds of drug combinations that we tested," says Jiu-Chao Yin, co-first author of the study. "By using four molecules that modulate four critical signaling pathways in human astrocytes, we can efficiently turn human astrocytes (glial cells) – as many as 70 percent – into functional neurons."