Growth factors and remyelination in the CNS.

It is now well established that there is an inherent capacity within the central nervous system (CNS) to remyelinate areas of white matter that have undergone demyelination. However this repair process is not universally consistent or sustained, and persistent demyelination occurs in a number of situations, most notably in the chronic multiple sclerosis (MS) plaque. Thus there is a need to investigate ways in which myelin deficits within the CNS may be restored. One approach to this problem is to investigate ways in which the inherent remyelinating capacity of the CNS may be stimulated to remyelinate areas of long-term demyelination. The expression of growth factors, which are known to be involved in developmental myelinogenesis, in areas of demyelination strongly suggests that they are involved in spontaneous remyelination. Therefore delivery of exogenous growth factors into areas of persistent demyelination is a potential therapeutic strategy for stimulating remyelination. This review will discuss the evidence that growth factors may have a role in promoting CNS remyelination by enhancing the survival and stimulating the proliferation and recruitment of remyelinating oligodendrocytes.