Background: Stromal cell-derived factor-1 (SDF-1)/CXC Chemokine receptor 4 (CXCR4) is an important cytokine, with multiple functions, which plays a crucial role in the recruitment of multiple stem cell types in the defect sites of central nervous system (CNS). Various strategies have been managed to improve functional recovery after spinal cord injury (SCI). One of these strategies is the use of factors to limit damage and increase recovery.

Objectives: In this study we investigated the effect of SDF-1 in spinal cord injury repair in a rat model.

Materials and Methods: Adult male Wistar rats were randomly divided to four groups (n = 5) as follows: Sham, SCI, SDF-1 and Vehicle. Spinal cord injury model was created by contusion of T8-T9 by clips and SDF-1 infusion pump implanted in the neck region. One week after injury, 5-Bromo-20-Deoxyuridine (BrdU) was injected to trace the proliferative cells. Basso-Beattie-Bresnahan (BBB) test was performed to evaluate locomotor activity following SCI. Immunohistochemistry test was performed to determine proliferating cells, and real time polymerase chain reaction (PCR) was performed to detect the CXCR4 cells in tissue.

Results: Significant improvements in locomotor function were detected in the SDF-1 group compared with the SCI and vehicle groups (P < 0.05). The results showed that SDF-1 treatment increased proliferative cells at the spinal cord injury site. Real time PCR revealed that these proliferative cells are CXCR4 positive that intake Bromodeoxyuridine (Brdu).

Conclusions: These results showed that the administration of SDF-1a increases the number of proliferating cells in the injured area in the spinal cord and improves functional recovery.