Brain cells certainly could not sprout new communications lines to take over the jobs of nonfunctioning cells, it was said. Nor could they regenerate themselves after being hurt. Moreover, they absolutely could not divide to replenish the brain with new cells. So potent is this gene that when inserted into cells that normally would never become brain cells, it transforms them into brain cells. I find that this organ that seemed so inaccessible, that seemed as if it could not be repaired just a few short years ago, now appears to be monumentally plastic, and now we are beginning to take advantage of its healing powers.
Neurotrophic factors are like nannies to brain cells.
They are there when the cells are first born, making sure they are nourished, grow, and make the right connections. They are there throughout the life of the cells, guarding their health and repairing damage. When neurotrophic factors decline or disappear, brain cells quickly fall down on the job, shrink and eventually die. This happens because the factors are no longer there to protect cells from being chopped up by free radicals, molecular piranhas created by normal body chemistry. The discovery of neurotrophic factors has opened the door to new generations of therapeutic agents that can revive sputtering brain cells, repair those that are damaged, rescue dying ones, and generate new cells.