Abstract:

BACKGROUND: There is no effective therapeutic strategy for spinal cord injury in clinic. Olfactory ensheathing cells (OECs) transplantation for spinal cord injury has obtained great progress. NG2, an important chondroitin sulfate proteoglycan molecule, suppresses axon growth.
OBJECTIVE: To explore effects of OECs transplantation on expression of NG2 in spinal cord injury rats, and to analyze action pathway of OECs transplantation in repair of spinal cord injury.
METHODS: A total of 112 rats were equally and randomly divided into four groups: blank group, model group, OECs group and DF12 group. In the blank group, rat spinal cord was completely transected at T₁₀, and partially transected at T₉ and T₁₁. No other treatment was performed. Animal models of spinal cord injury were established using spinal cord transsection in other three groups. In the OECs group, OECs transplantation was performed. Each transplanted rat received a total of 20 000 cells. In the DF12 group, DF12 culture medium was injected at the same area. At 1, 3, 7, 14, 28, 42 and 56 days following spinal cord injury, NG2 expression was evaluated according to SP kit instructions.
RESULTS AND CONCLUSION: In the blank group, NG2 appeared low expression. In the model group and DF12 group, NG2 expression increased at 24 hours. A highest expression of NG2 was present at 7 days. NG2 expression decreased obviously at 4 weeks. It only appeared local expression at 6 and 8 weeks. In the OECs group, moderately NG2 expression was presented on injury region at 1 day; the expression level was lower in the model group and DF12 group at identical time points, but higher than in the blank group. These indicate that NG2 expression was in a lower lever after OECs transplantation; it was inhibited by OECs transplantation. OECs transplantation would eliminate the chemical barrier of NG2，so that the injured nerve could regenerate. It may be one of the mechanisms of OECs transplantation for treating injured spinal cord.