Once severed by injury, axons in the spinal cord or optic nerve cannot regenerate and remain disconnected from their original target areas. As a result, affected patients suffer permanent functional impairment or disability such as paraplegia or blindness. “Using a low dose of Taxol locally at the site of injury is crucial to leveraging the regeneration-promoting effects of Taxol”, says Dietmar Fischer, Professor of Experimental Neurology, Department of Neurology, Heinrich-Heine-Universität Düsseldorf, Germany.
These research results have most recently been published in the Journal of Neuroscience (February, 16, 2011 issue). Similar findings were obtained in the spinal cord of rats studied by an international research team led by the Max-Planck-Institut für Neurobiologie, Martinsried, Germany, and published a few days ago in the journal Science. These results demonstrate that Taxol can be used in various parts of the brain and spinal cord to successfully facilitate nerve fiber regeneration.
Used in the right dose, the drug simultaneously targets several mechanisms that normally prevent nerve growth: Taxol stabilizes specific structures (microtubules) in the growth cones of injured nerve fibers, resulting in substantially enhanced elongation. In addition, Taxol abolishes growth cone sensitivity to growth-blocking molecules which are normally in their vicinity after injury. Moreover, local administration of this cancer drug delays scar formation at the site of injury and suppresses the synthesis of growth-inhibiting molecules, thus substantially reducing this barrier to regeneration.
These current findings, generated independently and simultaneously by two teams of reseachers in different models – the spinal cord in one study and the rat optic nerve in the present study – are encouraging indeed, holding out the promise of continued therapeutic development as these results have been obtained for a clinically established human drug. “We are cautious about predicting the potential of Taxol or similar drugs for use in humans”, Prof. Fischer emphasizes, “although Taxol or similar drugs might be promising candidates for the treatment of injuries to the central nervous system, be it from stroke or trauma. While more studies are clearly needed, from the scientific standpoint we now have an additional strategy for the development of new treatments for repairing central nervous system injuries.”
Contact: Prof. Dr. Dietmar Fischer, Experimentelle Neurologie, Klinik für Neurologie, Universitätsklinikum Düsseldorf, Phone: +49 015253838060, Mobile: +49 (0)173 3299792, E-mail: firstname.lastname@example.org; www.fischerlab.de