| Objective: To observe the effect of transcrianal magnetic stimulation (TMS) combined with bone marrow mesenchymal stem cells (BMSCs) transplantation on motor function in rats with spinal cord injury (SCI) and explore its mechanism. Methods: Totally, 60 specific-pathogen-free Sprague-Dawley rats were randomly assigned into 5 groups (12 in each group), including group A with sham operation without SCI, group B with SCI only, and group C-E with SCI and treatments of BMSCs transplantation, TMS, BMSCs transplantation combined with TMS, respectively. The SCI model was established with Allen’s method. Motor function was evaluated using BBB scale for all the rats at the day one, 14, and 28 after the SCI operation. Injured spinal cord tissue specimens were sampled at 4th week after the SCI operation for observations of NeuN expression with immunofluorescent staining and detections of GFAP, GAP-43, Nogo-A protein expression with Western blot. Results: At 4th week after the SCI operation, the rats with BMSCs transplantation, TMS and TMS combined with BMSCs transplantation had insignificantly higher BBB scale scores than in those without the treatments (P<0.01). The BBB scale scores in the rats with TMS combined with BMSCs transplantation were significantly higher than those in the rats only with SCI operation (P<0.001) and with single treatment of BMSCs transplantation (P<0.01). The expression of NeuN in BMSCs, TMS and TMS + BMSCs groups was up-regulated compared to the SCI group, and the up-regulation of NeuN was more significant in the combined treatment group. Up-regulated expression of GAP-43 and down-regulated expression of GFAP and Nogo-A in spinal cord tissues were measured in the SCI rats with the treatments of BMSCs transplantation, TMS and TMS combined with BMSCs transplantation. All the up- and down-regulated protein expression levels were more re-markable for the rats with TMS combined with BMSCs transplantation therapy. Conclusion: BMSCs transplantation, TMS and TMS combined with BMSCs transplantation treatment could up-regulate the expression of GAP-43, but down-regulate the expression of GFAP and Nogo-A in spinal cord tissues of SCI rats, which may promote neuronal synapsis formation and inhibit cicatrization of wounds through improving microenvironment and increasing neural factor secretion, finally promoting motor function in rats with SCI. The effect of combined treatment group is more satisfactory. |
