Biodegradable polyurethane nerve conduits functionalized with NDP-MSH-loaded self-assembling peptide hydrogels for...

Area of Science:

• Biomaterials Science
• Neuroscience
• Regenerative Medicine

Background:

• Autologous nerve grafting is the gold standard for peripheral nerve repair but has limitations.
• Nerve guidance conduits (NGCs) are a promising alternative.
• Developing effective NGCs requires balancing structural support with bioactivity.

Purpose of the Study:

• To engineer a biodegradable NGC incorporating a pH-responsive self-assembling peptide (SAP) loaded with NDP-MSH.
• To evaluate the NGC's ability to provide mechanical support and controlled release of NDP-MSH.
• To assess the therapeutic effects of NDP-MSH@SAP@BWPU conduits on peripheral nerve regeneration in a rat model.

Main Methods:

• Fabrication of biodegradable waterborne polyurethane (BWPU) conduits with 17 mol% PEG.
• Functionalization of BWPU conduits with NDP-MSH-loaded SAP.
• In vitro assessment of NDP-MSH's effect on oxidative stress in Schwann cells.
• In vivo evaluation of conduit performance in 10-mm rat sciatic nerve defects compared to autografts.

Main Results:

• NDP-MSH demonstrated cytoprotective effects against oxidative damage in vitro.
• NDP-MSH@SAP@BWPU conduits reduced apoptosis and promoted an M2 immune microenvironment in vivo.
• At 60 days, NDP-MSH@SAP@BWPU conduits achieved structural, functional, and electrophysiological outcomes comparable to autografts.

Conclusions:

• NDP-MSH delivery via BWPU-SAP conduits effectively biofunctionalizes biodegradable NGCs.
• This strategy offers a viable alternative to autografts for peripheral nerve repair.
• The engineered NGC provides mechanical support and controlled release of therapeutic peptides.