Scientists of the Max Planck Institute of Neurobiology in Martinsried and their colleagues from the Kennedy Krieger Institute and University of Miami in the United States, and the University of Utrecht in the Netherlands, have now shown that the cancer drug Taxol (see structure) reduces both regeneration obstacles. Frank Bradke and his team at the Max Planck Institute of Neurobiology in Martinsried study the mechanisms inside CNS nerve cells responsible for stopping their growth. As per the claim by the researchers, protein tubes (micro tubules) have a parallel arrangement in the tip of growing nerve cells, stabilizing cells and actively pushing the cell end forward. This arrangement is lost in injured CNS cells. So how can the order of the microtubule be kept or regained in these cells? And once the cells start growing, how can they overcome the barrier of the scar tissue? Together with their colleagues from the United States and the Netherlands, the Max Planck scientists have now found a common solution for both problems.
Taxol, the trade name of a drug currently used for cancer treatment, has now been shown to promote regeneration of injured CNS-nerve cells.
Researchers claim that, Taxol promotes regeneration of injured CNS-nerve cells in two ways:
Taxol stabilizes the microtubules so that their order is maintained and the injured nerve cells regain their ability to grow. In addition, Taxol prevents the production of an inhibitory substance in the scar tissue. The scar tissue, though reduced by Taxol, will still develop at the site of injury and can thus carry out its protective function. Yet growing nerve cells are now better able to cross this barrier.
"This is literally a small breakthrough", says Bradke.
Experiments in rats performed by this group verified the effects of Taxol. These researchers supplied the injury site after a partial spinal cord lesion with Taxol via a miniature pump. After just a few weeks, animals showed a significant improvement in their movements. So far researchers tested the effects of Taxol immediately after a lesion. Researchers next plan is to investigate whether Taxol is as effective when applied onto an existing scar several months after the injury. As the research is still in the state of basic research and a variety of obstacles remain and eventually, pre-clinical trials will need to be done, "however, researchers believe that this is a very promising path........
