E-jet 3D printed aligned nerve guidance conduits incorporated with decellularized extracellular matrix hydrogel encapsulating extracellular vesicles for peripheral nerve repair.

Artículo

Peripheral nerve injury (PNI) as a common clinical issue that presents significant challenges for repair. Factors such as donor site morbidity from autologous transplantation, slow recovery of long-distance nerve damage, and deficiencies in local cytokines and extracellular matrix contribute to the complexity of effective PNI treatment. It is extremely urgent to develop functional nerve guidance conduits (NGCs) as substitutes for nerve autografts. We fabricate an aligned topological scaffold by combining the E-jet 3D printing and electrospinning to exert synergistic topographical cue for peripheral nerve regeneration. To address the limitation of NGCs with hollow lumens in repairing long-distance nerve defects, we modified the internal microenvironment by filling the lumen with umbilical cord-derived decellularized extracellular matrix (dECM) hydrogels and extracellular vesicles (EVs). This approach led to the development of a functional HE-NGC. Herein, the HE-NGCs provided obvious guidance and proliferation to SCs and PC12 in vitro due to the sustained-release effect of dECM hydrogels and the outstanding proliferation-promoting role of EVs. The HE-NGCs was surgically implanted in vivo to bridge 12-mm gap sciatic nerve defect in rats and it had a satisfactory effect in reestablishment of the sciatic nerve, including the recovery of motor functions and the myelination. Further studies revealed that HE-NGCs might promoted axon growth by activating the PI3K/Akt/mTOR and inhibiting the MAPK signaling pathways. These findings indicate that HE-NGCs effectively promote nerve regeneration, offering a promising strategy for applications in peripheral nerve repair.