Repairing Brain Connections
Researchers find a new pathway for neuron repair
Researchers have discovered a brand-new pathway for repairing nerve cells that could have implications for faster and improved healing. These findings demonstrate that dendrites, the component of nerve cells that receive information from the brain, have the capacity to regrow after an injury.
Using the fruit fly (Drosophila) as a model system, the researchers took what Rolls calls a “radical approach,” cutting off all of the dendrites in neuron cells.
“By cutting off all the dendrites, the cells would no longer be able to receive information, and we expected they might die. We were amazed to find that the cells don’t die. Instead, they regrow the dendrites completely and much more quickly than they regrow axons. Within a few hours they’ll start regrowing dendrites, and after a couple of days, they have almost their entire arbor. It’s very exciting — these cells are extremely robust.”
Moreover, it appears that dendrite regeneration happens independently of axon regeneration. When Rolls and her colleagues blocked the key signaling molecules that are required for axon regeneration in all animals, they found that dendrites were unaffected and continued to regrow. “This means that, not only do these neurons have an incredible ability to generate, they have two different regeneration pathways: one for axons and one for dendrites,” she said. “Because it has not even been clear that dendrites can regenerate, it’s a complete open question about what might be involved in that process.
Repairing brain connections requires an in-depth knowledge of the nervous system and a systematic approach to activating multiple sensory systems together to remap communicating connections between neurons throughout the brain.
The research was funded by the National Institutes of Health Grant #R01 GM085115 and the Pew Charitable Trusts. (Rolls was a Pew Scholar in the biomedical sciences.)