By using keratin to activate these cells, were trying to tap into the natural healing cascade, said Van Dyke. We believe that keratin helps amp up Schwann cell activity and give the nerve regeneration process a head start.
The laboratory studies showed that keratin activated Schwann cells and increased their proliferation and migration. Next, the scientists used a keratin-filled tube to attempt to repair a 4 millimeter nerve gap in mice -- a fairly significant gap considering the size of the animal.
The results from these animals were compared with animals treated with an empty nerve guidance conduit and with animals treated with a nerve graft.
After six weeks, 100 percent of the animals in the keratin and nerve graft groups showed visible nerve regeneration across the gap, compared to only 50 percent who got the empty conduit. The speed of repair was best in the keratin group.
The scientists then tested the function of the regenerated nerve. The speed of nerve impulses was best in the keratin group. The amount of signal that got through the nerve was better in the keratin group than in the empty tube group. The study was recently highlighted in the journal Science.
The results suggest that a conduit filler derived from hair keratins can promote an outcome comparable to a grafted nerve, said Van Dyke.
In the study, the nerve function did not translate into recovery of muscle function, but the scientists suspect they may have tested too early, before the nerve had time to regenerate to the muscle. It is known that muscle function recovery lags behind nerve recovery. Future studies will focus on regeneration across larger gaps and will test whether nerve regenera
|Contact: Karen Richardson|
Wake Forest University Baptist Medical Center