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Abstract
Objective
Promoting axonal regeneration is one of essential goals to be achieved for effective repair from spinal cord injury (SCI). The authors performed an experiment on the effect of Wnt-3a producing fibroblast injection on SCI.
Methods
SCI is performed by New York University (NYU) impactor in 21 rats, and 1 week after injury, the rats were grouped into Wnt-3a producing fibroblast transplantation group (Wnt group, n=7), fibroblast transplantation group (vehicle group, n=7), and no treatment group (sham group, n=7). For the behavioral tests, the Basso, Beattie and Bresnahan (BBB) locomotor rating scale were evaluated. Also, to study radiological evidence of axon regeneration, the rats underwent manganese enhanced MRI (ME-MRI) twice, before treatment and 5 weeks after treatment.
Results
On average, the sham group and vehicle group rats attained BBB score of 10.4 and 12.1, respectively, whereas Wnt group rats achieved a significantly higher BBB score of 14.0 at 5 weeks after treatment. At 5 weeks after treatment, relative signal intensities of ME-MRI was significantly higher in the Wnt group than in the vehicle group and sham group at 5 weeks after injury.
Figures and Tables
FIGURE 1
The spinal cord injury was performed according to the NYU system developed by Gruner 1992. NYU: New York University.
FIGURE 2
ME-MRI of Wnt group. A: At a week after injury, ME-MRI revealed showed manganese uptake was decreased at caudal to the lesion (arrowhead). B: At 5 weeks after treatment, ME-MRI revealed that manganese uptake by active neuronal tissue resulted in signal enhancement below injury level (arrowhead). ME-MRI: manganese enhanced MRI.
FIGURE 3
Diagram of BBB locomotor scale. At 1 week after injury, the rats were treated (arrow). 5 weeks after treatment, mean values of Wnt group showed significant improvement compared to vehicle group and sham group (*p<0.001). BBB: Basso, Beattie and Bresnahan, AVOVA: analysis of variance.
FIGURE 4
Diagram of the relative signal intensities. A week after injury, the relative signals of all three groups have no significant differences (left histogram of each group). 5 weeks after treatment, mean values of the relative signal intensities showed significant differences between three groups, statistically (right histogram of each group, *p<0.001).
References
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