Photobiomodulation inhibits the expression of chondroitin sulfate proteoglycans after spinal cord injury via the Sox9 pathway

Spinal cord injury (SCI) often leads to the formation of glial scars, which contain substances called chondroitin sulfate proteoglycans (CSPGs). These CSPGs can hinder the regeneration of nerve fibers, making it difficult for the spinal cord to repair itself. This study explores how photobiomodulation (PBM), a light-based therapy, can help reduce CSPG formation and improve motor function after SCI. The researchers used a mouse model of SCI and applied PBM treatment to the injured area. They found that PBM not only restored motor function but also reduced the expression of CSPGs. Further analysis revealed that PBM inhibited genes related to proteoglycan production, with versican, a specific type of proteoglycan, showing significant changes. The study also investigated the molecular pathways involved and found that PBM influenced the Smad3/Sox9 and MAPK/Sox9 pathways, which play a role in CSPG accumulation. These findings suggest that PBM can modulate CSPG expression, with versican being a key target molecule, potentially improving outcomes after spinal cord injury.

• 1
  PBM irradiation markedly increased Basso Mouse Scale scores in SCI model mice from day 7 post-injury, and this difference was maintained until day 28.
• 2
  PBM treatment markedly decreased CSPG expression at 3, 7, 14, and 28 dpi in the SCI + PBM group compared with the SCI group.
• 3
  Versican expression was obviously lower in the SCI + PBM group than in the SCI group.