Key molecules in axon regeneration

Abstract

Development of adult mammal central nervous system (CNS) is closely related to loosing the ability spontaneously regenerate after injuries. On the other hand, peripheral nervous system (PNS) maintains its capability to regenerate after injuries entire lifespan. Ability to regenerate successfully is mainly determined by the balance of growth promoting and growth inhibiting factors, expressed by both neuronal and non-neuronal cells found in the injury site. Some of signaling cues involved in regeneration are expressed in adult CNS constantly, although expression of other factors occurs only in the injury site of adult mammal. Ephrins, Semaphorins, Slits and Netrins are among most important molecules involved in lack of success in regeneration of CNS. PNS neurons initiate reparation mechanisms right after development of injury, and are capable to recover functional activity even if an area of injury is more than several centimeters wide. Understanding of differences between CNS and PNS regeneration and factors involved in functional nervous system recovery are crucial for both in depth analysis of plasticity of adult mammal neural system, and for developing new treatment strategies.