Nanofibrous nerve conduit-enhanced peripheral nerve regeneration

Area of Science:

• Biomaterials Science
• Neuroscience
• Regenerative Medicine

Background:

• Fibre structures mimic natural nerve architecture, offering potential for synthetic nerve conduits.
• Previous studies show benefits of fibers for nerve regeneration, but in vivo data on fiber size effects is limited.

Purpose of the Study:

• To investigate the impact of electrospun conduit fiber diameter on peripheral nerve regeneration.
• To compare the efficacy of nanofiber and microfiber conduits in a rat sciatic nerve injury model.

Main Methods:

• Electrospinning was used to create poly (ε-caprolactone) (PCL) conduits with aligned microfibers (981 nm) or nanofibers (251 nm).
• A 15-mm critical defect gap in rat sciatic nerves was used for in vivo evaluation.
• Histological analysis, retrograde labeling, and electrophysiological assessments (CMAP) were performed at three months post-implantation.

Main Results:

• Axonal regeneration occurred in all fibrous conduits, but not in the control (non-porous film) group.
• Nanofiber conduits yielded significantly more myelinated axons and thicker myelin sheaths than microfiber conduits.
• Nanofiber conduits led to a significant increase in regenerated sensory neurons and improved motor function (higher CMAP amplitudes, lower latency).

Conclusions:

• Fiber diameter critically influences peripheral nerve regeneration outcomes.
• Nanofiber conduits demonstrate superior performance in promoting nerve regeneration compared to microfiber conduits.
• These findings provide valuable insights for optimizing the design of future nerve regeneration guides.