Vat-Polymerized 3D Printed Multichannel Nerve Conduit Functionalized With Bacopa monnieri and Collagen Dipeptides...

Peripheral nerve injury (PNI) affects both autonomic and somatic signaling. PNI autografts are limited by donor nerve morbidity and availability. The intricate structure of peripheral nerves cannot be accurately reproduced using approved nerve conduits. They lack neuroprotective and antioxidant properties that could aid nerve regeneration and reduce reactive oxygen species (ROS) after injury. This study presents a multichannel hydrogel nerve conduit that incorporates Bacopa monnieri extract for its antioxidant and neuroprotective properties, along with collagen dipeptides. The design incorporates nanofibrous electrospun and porous hydrogel matrices that replicate the neuronal extracellular matrix. In vitro, hydrogels reduce oxidative stress and increase nerve cell adhesion and proliferation. In vivo study encapsulates the multichannel nerve conduit within a bilayer scaffold of electrospun nanofibers and a 3D-printed polymeric framework. The 3D-printed framework provides mechanical stability and reduces hydrogel degradation, while the electrospun layer covers the epineurium for long-term nerve regeneration. A partially transacted sciatic nerve model reveals axonal development, myelination, and improvement in motor-sensory function, suggesting nerve regeneration. The additive therapeutic effect of Bacopa monnieri and collagen dipeptides increased the diameter of myelinated nerve fibers, enhanced nerve saltatory conduction, and promoted fascicular development. This multichannel nerve conduit accelerates peripheral nerve regeneration by mimicking anatomical structure.