Impact of Endurance Training on Regeneration of Axons, Glial Cells, and Inhibitory Neurons after Spinal Cord Injury: A Link between Functional Outcome and Regeneration Potential within the Lesion Site and in Adjacent Spinal Cord Tissue

Endurance training before spinal cord injury (SCI) can help activate pathways that aid survival, brain plasticity, and nerve regeneration. However, it's not clear which cells are most important for improving function after SCI. This study found that training alone increased immature CNP-ase oligodendrocytes and altered the regulation of inhibitory GABA/glycinergic neurons, which are important for rhythm and movement. The results suggest that endurance training before SCI can improve the environment for nerve repair in the spinal cord, which leads to better neurological outcomes.

• 1
  Endurance training alone increased the gene expression and protein level of immature CNP-ase oligodendrocytes (~16%) at Th10, and caused rearrangements in neurotrophic regulation of inhibitory GABA/glycinergic neurons at the Th10 and L2 levels.
• 2
  Training + SCI upregulated markers for immature and mature (CNP-ase, PLP1) oligodendrocytes by ~13% at the lesion site and caudally, and increased the number of GABA/glycinergic neurons in specific spinal cord regions.
• 3
  In the pretrained SCI group, the functional outcome of hindlimbs positively correlated with the protein levels of CNP-ase, PLP1, and neurofilaments (NF-l), but not with the outgrowing axons (Gap-43) at the lesion site and caudally.