Melatonin Promotes the Recovery of Motor Function in Mice After Spinal Cord Injury by Inhibiting Oxidative Stress and Inflammatory Responses

WANG Anning; SUN Jufeng

doi:10.3969/j.issn.2096-305X.2025.03.007

Abstract：Objective To investigate the effect and molecular mechanism of melatonin on nerve repair in spinal cord injury(SCI)mice.Methods 60 adult female C57BL/6 mice were selected and randomly divided into the Sham operation group(Sham group),the spinal cord injury group(SCI group),and the melatonin treatment group after spinal cord injury(melatonin group).The mouse spinal cord contusion model was established by using the Allen tapping method.After the operation,the mice in the Melatonin group were intraperitoneally injected with melatonin.The recovery of motor function in SCI mice was evaluated double-blind using the behavioral score sheet.Seven days after the operation,Nuclear factor erythroid 2-related factor-Nrf2 was tested by fluorescence quantitative polymerase chain reaction(RT-qPCR)and Western Blot,respectively The expression levels of mRNA and protein chemical kits were used to detect the changes in the contents of Superoxide Dismutase(SOD)and Malondialdehyde(MDA)in the damaged spinal cord tissues of SCI mice.Results At 7 days after the operation,the behavioral scores of mice in the Melatonin group were significantly higher than those in the SCI group.In addition,the mRNA and protein expressions of Nrf2 and HO-1 increased,while the mRNA and protein expressions of TNF-α and IL-1β significantly decreased.The activity of SOD enzymes in the spinal cord tissue increased,and the content of MDA decreased.Conclusion Melatonin promotes the functional recovery of spinal cord injury by down-regulating the expression levels of oxidative stress and inflammatory factors in mouse lesions.