Brain-Healing Nanotechnology

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The success of the treatment is somewhat surprising, because the chemicals that stimulate nerve growth and stem cells used in other research into nerve tissue regeneration were not used here. "They just used the peptides and the cells reconnect with the target, and then the functional behavior can be seen in the animals -- that's amazing to me," says Tat Fong Ng, an investigator at the Harvard-affiliated Schepens Eye Research Institute in Boston.

Ng wonders whether adding such chemicals and cells to the treatment might speed growth, perhaps making it possible to reconnect distant parts of the brain separated by an injury, such as in a stroke. The researchers say this might be done by forming a path through a damaged area using minimally invasive surgery and injecting the amino acid chains, which would then assemble into the fibers. The channel would both allow nerve cells to grow and guide them to the right area.

So far, the nanofiber treatment has caused no problems, such as inflammation or aggregation of fibers, in small animals. Over a few weeks, the fibers break down and leave the body in the urine. As building blocks for proteins, the amino acids might even be used for new cell growth, the researchers say. Also, because the fibers are made of natural amino acids that the body can use, the researchers are optimistic that no reaction against them will occur in studies with large animals and humans.

Ed Tehovnik, a neuroscientist at MIT who was not involved with the work, says it has "quite a lot of promise," adding that it "may only be the start. There could be other types of nano-agents that [the MIT researchers] develop that could promote growth even better. I see this as the beginning, not the end, which is a good thing."

Home page image courtesy of the National Academy of Sciences. Caption: Nerve cell regrowth (in green) shows a damaged area of the brain that has been repaired.