Pits Researchers vs. A major challenge for neuroscientists lies in coaxing nerve cells to regenerate their connections after injury to the brain or spinal cord. Recently, a group led by Larry Benowitz, HMS associate professor of neurosurgery at Children's Hospital, discovered that inosine, a small molecule normally found in low levels in most cells, can stimulate nerve cells to do just that. Our findings indicate that the effects of multiple growth factors converge upon a single enzyme which, in turn, regulates this whole constellation of genes.
Growth factors act to overcome the suppression of axon growth.
But inosine may be capable of eliminating the need for such factors. Benowitz and his colleagues are working on isolating the gene encoding the enzyme upon which inosine works. Affecting one of every 15,000 infants in the U.S., PKU usually results from a deficiency of the enzyme phenylalanine hydroxylase, and can cause mental retardation and other medical problems if left untreated. The current treatment involves excluding high protein foods, such as meat, milk, eggs, and nuts, since all protein contains phenylalanine. Wheat products also are off limits.