Environmental cues determine the fate of astrocytes after spinal cord injury

Following CNS lesions, naïve astrocytes are converted into reactive astrocytes and eventually into scar-forming astrocytes that block axon regeneration and neural repair. Recent use of various genetic tools has made tremendous progress in better understanding genesis of reactive astrogliosis. The interactions between upregulated type I collagen and its receptor integrin β1 and the N-cadherin-mediated cell adhesion appear to play major roles for local astrogliosis around the lesion.

• 1
  Reactive astrocytes isolated from injured spinal cord form scarring astrocytes when transplanted into injured spinal cord, but revert in retrograde to naive astrocytes when transplanted into naive spinal cord.
• 2
  Upregulation of type 1 collagen (Col 1) and N-cadherin around the lesion plays important roles in astrogliosis.
• 3
  Blocking Col 1-integrin β1 signaling pathway and/or N-cadherin-mediated cell adhesion may suppress scar formation and become an effective approach for providing axon regeneration after CNS injury.