Neurotrophic factors in the therapy of peripheral neuropathy.

Neurotrophic factors are proteins that promote the survival and differentiation of specific populations of neurones. With the successful cloning and large-scale production of many different neurotrophic factors, it has become practical to consider their application in the treatment of neurological disease. Several groups of neurotrophic factors hold particular promise for the therapy of peripheral nervous system disease in the near future. These include the neurotrophin gene family, cytokines such as CNTF and the IGF family. Evidence is accumulating that an abnormal availability of some of these factors may contribute towards the pathophysiology of some types of neuropathy, most notably diabetic neuropathy. Pre-clinical studies in animal models have demonstrated the likely efficacy of factors such as NGF for small-fibre sensory neuropathy, BDNF, CNTF and IGF-I for motor neurone disease, and NT-3 for large-fibre neuropathy. Clinical trials of several growth factors are currently underway for the treatment of peripheral nerve disease, and other clinical trials are currently being planned.