Evaluación de la regeneración axonal y de la recuperación funcional tras la inyección intraneural de factor de crecimiento insulínico tipo I en isoinjertos nerviosos criopreservados en el modelo de defecto ciático de rata

Resumo

Purpose Establishing a nerve cryopreservation protocol, and investigating intraneural IGF-1 (Insulin-like growth factor I) effect in cryopreserved isografts. Material and methods Two cryopreservation protocols were compared: Dimethyl sulfoxide (DMSO) and DMSO with human albumin. The structural evaluation was performed through histological analysis. The viability was assessed with calcein AM (CAM) - 4',6-diamidino-2- phenylindole (DAPI). In order to evaluate the effect of IGF-1, 57 rats were randomly divided into three groups: (1) autograft; (2) cryopreserved isograft; (3) cryopreserved isograft with intraneural IGF-1. 12 weeks after surgery, the functional recovery (Walking track, electrophysiology studies, gastrocnemius mass index (GMI)) and nerve regeneration (histomorphometry) were assessed. XXIV Results Nerve architecture was correctly preserved after cryopreservation. Cell viability was significantly higher in the group with albumin. In the prospective study, functional and histological results revealed significant improvement of the variables after the addition of the growth factor as compared to isograft alone. Conclusions The viability was significantly increased when albumin was added to the cryopreservation protocol. Intraneural injection of IGF-1 significantly improved axonal regeneration and functional recovery, achieving results comparable to those of the autograft.