Effects of electroacupuncture combined with hydrogel on the formation and changes in the glial scar in rats with spinal cord injury

Objective: To observe the effect of electroacupuncture(EA) combined with oriented conductive bioprotein hydrogel(OCBH) on the recovery of nerve function in rats with complete spinal cord injury(SCI)and to explore its effect and mechanism on the formation and changes of glial scars.Methods: A total of 72 female Sprague-Dawley rats were randomly divided into groups according to the treatment received. A rat model of complete SCI was constructed using a spinal cord transection.Behavioral assessments, hematoxylin-eosin(H&E) staining, immunofluorescence staining, and Western blotting were performed at a fixed period after the operation.Results: The material group and the material + EA group obtained better results in the behavioral assessments(all P <.05) and the H&E staining. In the immunofluorescence staining and Western blotting,the GFAP protein was expressed more and denser in the material group and the material + EA group than in the model group, and the density of the GFAP expression in the material + EA group was lower at week 12 than in the material group(all P <.05). The expression of complement C3 in the model, material,and material + EA groups decreased in turn. Some inflammatory factors and the NF-κB signaling pathway showed similar results in the Western blotting(all P <.05). The expression of the GDNF protein in the material + EA group was significantly higher than that in the model group and the material group(both P <.01).Conclusion: EA combined with OCBH can promote the recovery of motor functions after SCI by facilitating the formation of glial scars in the early stage, preventing the further spread of an inflammatory response that would affect the activation of A1/A2 astrocytes and change the morphology of glial scars at the spinal cord-material interface in its late stage.