Microenvironment Imbalance of Spinal Cord Injury

Spinal cord injury (SCI) is a serious damage to the central nervous system, has historically been considered an incurable impairment worldwide. Patients with SCI suffer a lot both in terms of physiology and psychology and simultaneously, SCI has been a major burden on the society with increasing prevalence The spinal cord consists of the gray and white matter which contains nerve cell bodies and ascending and descending tracts. Thus, the different locations and the extent of SCI can cause varying degrees of disability, from partial loss of sensory or motor function to complete paralysis below the injured location, as well as acute and chronic complications Following contusion injury, the balance of the spinal cord microenvironment is disrupted, which leads to a series of pathophysiological changes; beneficial factors become downregulated, and harmful factors become upregulated after SCI. The micro-environment imbalance consists of three levels at different times and sites: molecules, cells and tissues.

• 1
  Microenvironment imbalance is defined as an increase in inhibitory factors and decrease in promoting factors for tissues, cells and molecules at different times and spaces.
• 2
  There are imbalance of hemorrhage and ischemia, glial scar formation, demyelination and re-myelination at the tissue’s level. The cellular level imbalance involves an imbalance in the differentiation of endogenous stem cells and the transformation phenotypes of microglia and macrophages.
• 3
  The molecular level includes an imbalance of neurotrophic factors and their pro-peptides, cytokines, and chemokines. The imbalanced microenvironment of the spinal cord impairs regeneration and functional recovery.