Hyperbaric oxygen improves functional recovery of the injured spinal cord by inhibiting inflammation and glial scar formation

BACKGROUND: Inflammation and glial scar formation determine the recovery process after spinal cord injury. Hyperbaric oxygen is used as a rehabilitation therapy for various clinical diseases, including spinal cord injury. However, the relationship between hyperbaric oxygen therapy and inflammation or glial scar is not fully understood. OBJECTIVE: The aim of this study was to investigate the therapeutic effect and molecular mechanism of hyperbaric oxygen on spinal cord injury. METHODS: A total of 54 developing female Sprague-Dawley rats were randomly divided into sham group, spinal cord injury group, and hyperbaric oxygen group, with 18 rats in each group. The model of spinal cord injury was established using Allen's method. Hyperbaric oxygen therapy was administered once a day until the rats were killed. RESULTS: The results demonstrated inflammation and glial scar formation are involved in secondary spinal cord injury. After hyperbaric oxygen treatment, there was a notable improvement of the locomotor function in rats. Hyperbaric oxygen reduced the inflammatory reaction and glial scar formation by inhibiting inflammation-related factors iNOS and COX-2 and glial scar-related components GFAP and NG2. This process may be achieved by inhibiting AKT and NF-kB pathways. CONCLUSIONS: Hyperbaric oxygen effectively promotes the recovery of spinal cord injury by inhibiting inflammation and glial scar formation.