Matrix Metalloproteinases and Neurotrauma: Evolving Roles in Injury and Reparative Processes

Matrix metalloproteinases (MMPs) are a family of enzymes involved in tissue remodeling and wound healing. In the central nervous system (CNS), MMPs are implicated in neurodegenerative diseases and stroke-related damage. While increased MMP activity is often associated with damage in the CNS, research also suggests that MMPs participate in recovery processes after traumatic injuries to the adult and developing CNS. The specific roles of MMPs in the CNS depend on the timing and context of their activity, influencing both injury and repair mechanisms following neurotrauma.

• 1
  MMP-9 is elevated early after injury and is associated with blood-brain barrier disruption and inflammation, while MMP-2 is upregulated later and involved in wound healing.
• 2
  MMPs can disrupt the blood-brain barrier by degrading tight junction proteins and basal lamina components, contributing to edema and inflammation following CNS trauma.
• 3
  MMPs mediate leukocyte infiltration into the injured CNS, with MMP-9 facilitating neutrophil transmigration and MMP-12 influencing macrophage migration.