Repair of nerve injury by implanting prostheses obtained from isogenic acellular nerve segments

Efficacy evaluation of personalized coaptation in neurotization for motor deficit after peripheral nerve injury: A systematic review and meta-analysis

INTRODUCTION

Peripheral neurotization, recently as a promising approach, has taken effect in recovering motor function after damage to a peripheral nerve root. Neural anastomosis comprised of nerve conduit and neurorrhaphy participates in the nerve reconstruction. Current literature lacks evidence supporting an individualized coaptation for rescue of locomotor loss in rat subjects with paraplegia secondary to peripheral nerve injury (PNI).

METHODS

This meta-analysis intends to qualify the specificity of gap-specific coaptation in treating a paralyzed limb following PNI. We used a highly sensitive search strategy to identify all published studies in multiple databases up to 1 May 2019. All identified trials were systematically evaluated using specific inclusion and exclusion criteria. Cochrane methodology was also applied to the results of this study.

RESULTS

Twelve studies, including 349 rat subjects, met eligibility criteria. For a medium nerve defect (0.5-3.0 cm), nerve conduit was more likely than neurorrhaphy to precipitate axon regeneration and improve motor outcome of the hemiplegic limb (OR = 3.61, 95% CI = 1.80, 7.26, p < .0003) at 3-month follow-up, whereas neurorrhaphy might take its place in promoting limb motor function in a small nerve gap (<0.5 cm) (OR = 0.48, 95% CI = 0.22, 1.07, p < .007). For a small nerve defect, nerve conduit still demonstrated visible effectiveness in recovery of limb motion albeit poorer than neurorrhaphy (OR = 1.50, 95% CI = 0.92, 2.47, p < .05).

CONCLUSION

Selective neurotization facilitates motor regeneration after nerve transection, and advisable choice of neural coaptation can maximize functional outcome on an individual basis.

Exosomes and Their MicroRNA Cargo: New Players in Peripheral Nerve Regeneration

Peripheral nerve injury is a major clinical problem and often results in a poor functional recovery. Despite obvious clinical need, treatment strategies have been largely suboptimal. In the nervous system, exosomes, which are nanosized extracellular vesicles, play a critical role in mediating intercellular communication. More specifically, microRNA carried by exosomes are involved in various key processes such as nerve and vascular regeneration, and exosomes originating from Schwann cells, macrophages, and mesenchymal stem cells can promote peripheral nerve regeneration. In this review, the current knowledge of exosomes' and their miRNA cargo's role in peripheral nerve regeneration are summarized. The possible future roles of exosomes in therapy and the potential for microRNA-containing exosomes to treat peripheral nerve injuries are also discussed.