Nutlin-3a-PLGA Microspheres Promote Motor Function Recovery After Spinal Cord Injury In Rats

Objective To explore the effect of Nutlin-3a-PLGA microspheres on motor function recovery after spinal cord injury in rats.Methods Nutlin-3a-PLGA microspheres were prepared by single emulsion method.With random number tables,healthy female SD rats were randomly divided into injury only group,control group and experimental group,12 rats in each group were taken.All groups were suffered a complete right-hemisection at T10 with fine microdissection scissors.Other 3 rats were subjected to normal spinal cord eriochrome cyanine staining.Nutlin-3a-PLGA microspheres were then topically delivered to the lesion site in the experimental group.the control group received the same amount of Saline-PLGA microspheres.Myelin sheath was observed with eriochrome cyanine staining on postoperative 14 and 28 d.Catwalk gait analysis system(the regularity index,stand,forelimb footprint mean intensity,base of hindlimb support and ipsilateral footprint distance 5 temporal spatial parameters)was applied to describe the behavioral characteristics of the rats on preoperative 1 d and postoperative 14,21,28 d.Results As compared to the injury only group and control group after 4 weeks,experimental group demyelinating less and were arranged more closely in the eriochrome cyanine staining.As compared to the preoperative,there were differences in each behavior parameters of the postoperative in the injury only group and control group;regularity index,base of hindlimb support and ipsilateral footprint distance were different significantly in the experimental group.As compared to the injury only group and control group,left hindlimb stand and forelimb footprint mean intensity were decreased in experimental group,and regularity index increased on postoperative 14 d.Moreover,base of hindlimb support and ipsilateral footprint distance were significantly increased on postoperative 28 d.Conclusion Nutlin-3a-PLGA microspheres can improve conduction function and motor function in rats with spinal cord injury.And it may promote axonal regeneration of the injured segments.