Regeneration in the central nervous system: new strategies

Nerve injury in the peripheral nervous system is Vowed by prompt regeneration of nerve fibres from the proximal stump leading to functional recovery, No such regrowth occurs after injury to CNS fibre tracts. Regeneration in the CNS is impeded by at least three mechanisms: 1. the persistence of growth inhibitory myelin proteins in the distal stump, 2. scar formation at the lesion site, and 3. secondary cell death of the neuronal perikarya. Several strategies to foster regeneration in the CNS have been successfully developed in experimental animals: transplanation of peripheral nerve tissue, neutralisation of myelin-associated growth inhibitors, induction of inflammation, and pharmacological suppression of scar formation. Due to the complexity of the processes underlying regeneration failure in the CNS it is very likely that combined approaches are needed to induce regeneration in humans. Well defined lesion paradigms such as traumatic spinal cord injury appear most suitable for clinical approaches.