Determinants of Axon Growth, Plasticity, and Regeneration in the Context of Spinal Cord Injury

After a spinal cord injury, the central nervous system's ability to repair itself is limited. A major goal is to encourage axons, the long fibers that transmit nerve signals, to regrow. This regrowth is necessary for the nervous system to adapt, form new connections, and potentially restore function. However, even if axons regrow, it doesn't automatically mean that function is restored. The new connections need to be properly formed and integrated into existing neural circuits. Sometimes, axons can even create incorrect or harmful connections. This review examines the factors that affect axon regrowth after spinal cord injury, including both internal mechanisms within the nerve cells and external factors in the surrounding environment. Understanding these factors is crucial for developing effective treatments to promote meaningful recovery.

• 1
  Injured axons in the CNS often fail to regenerate and form dystrophic end bulbs, which persist at the lesion border.
• 2
  Axonal dieback occurs in two phases: an initial intrinsic retraction and a secondary phase mediated by infiltrating macrophages.
• 3
  The glial scar, particularly chondroitin sulfate proteoglycans (CSPGs), inhibits axon regeneration.