Regenerating CNS myelin — from mechanisms to experimental medicines

Promoting remyelination may be an effective therapeutic strategy for various disorders that are characterized by a loss of myelin, including multiple sclerosis. In this Review, Franklin and ffrench-Constant discuss recent developments in our understanding of remyelination and the efforts that are underway to enhance this process. Although the core concept of remyelination — based on the activation, migration, proliferation and differentiation of CNS progenitors — has not changed over the past 20 years, our understanding of the detailed mechanisms that underlie this process has developed considerably. We can now decorate the central events of remyelination with a host of pathways, molecules, mediators and cells, revealing a complex and precisely orchestrated process. These advances have led to recent drug-based and cell-based clinical trials for myelin diseases and have opened up hitherto unrecognized opportunities for drug-based approaches to therapeutically enhance remyelination.