Damage to the central nervous system, the brain and spinal cord, is currently irreparable. But this may change soon as researchers have now discovered that genetic and chemical treatment could help regenerate damaged nerves.
Future therapies could help repair nerve damage after people suffer spinal cord injury or brain trauma, said the study.
"Due to the complexity of the structure of the central nervous system, regrowth leads most often to incorrect rewiring, such as pain," said Simone Di Giovanni, a neuroscientist and neurologist from Imperial College London.
"The peripheral nervous system is much more simple and has effective, although partial, regeneration," noted the researchers.
Most spinal cord injuries are caused by damage to axons, the long extensions of neurons that send messages around inside the nervous system, the study pointed out.
The researchers found that when nerves are damaged in the peripheral nervous system, they emit signals to switch on a program to initiate nerve growth.
This program is "epigenetic", meaning that it can activate or deactivate genes without altering DNA.
They also identified a protein, called P300/CBP-associated factor (PCAF), as being central to initiating nerve regrowth.
The researchers found that when this protein was injected into mice that had damage to their central nervous system, it significantly increased the number of nerve fibers that grew back.
"This work opens an exciting new field of investigation, placing epigenetic regulation as a new, very promising tool to promote regeneration and recovery after spinal injury," Di Giovanni told Live Science.
The study appeared in the journal Nature Communications.