George Bittner and his colleagues from the University of Texas at Austin may have found a way to reattach severed nerves. Although only tested in rats, they have every hope that their technique will prove equally successful in humans.
First, why is it so difficult for severed nerves to regrow? Well, it isn’t for all animals. Invertebrates are able to reattach severed nerves in a few days. Mammals are not so lucky. When one of our nerves is cut or damaged, the nerve axon (the part that reaches out toward a muscle cell or another nerve) dies back in a process called Wallerian degeneration. It can take over a year for the nerve to grow back, and sometimes the proper connections never get remade. Invertebrates don’t suffer from Wallerian degeneration, and thus their nerves can simply reattach.
The researchers used a mix of chemicals to prevent the severed or crushed sciatic nerves of rats from undergoing Wallerian degeneration. They applied the antioxidant methylene blue keep the axonal ends open and polyethylene glycol to subsequently fuse them. The rats treated this way showed significant improvement within a week.
The researchers are hoping to begin clinical trials soon. If it works in humans, this would be a stunning breakthrough in treating nerve-damaged individuals.
Hat tip: The Skeptics’ Guide to the Universe