Hydroxypropyl Chitosan/Soy Protein Isolate Conduits Promote Peripheral Nerve Regeneration

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Peripheral nerve regeneration requires advanced scaffolds that support cell growth and factor release.
• Optimizing scaffold microstructure and function is crucial for successful nerve repair.

Purpose of the Study:

• To fabricate and characterize hydroxypropyl chitosan/soy protein isolate composite sponges (HCSS) for peripheral nerve regeneration.
• To evaluate the biocompatibility and efficacy of HCSS in promoting nerve repair and neurotrophic factor expression.

Main Methods:

• Fabrication of HCSS using a freeze-drying technique.
• Physicochemical characterization including SEM, FTIR, water absorption/retention, and compressive strength.
• In vitro cell proliferation and neurotrophic factor secretion assays using RSC96 cells.
• In vivo assessment of HCSS-based conduits in a rat sciatic nerve injury model, with and without stem cells.

Main Results:

• HCSS exhibited interconnected porous structures and enhanced water retention with increased soy protein isolate (SPI) content.
• HCSS-50 promoted RSC96 cell proliferation and neurotrophic factor secretion without excessive oxidative stress.
• HCSS-50 significantly upregulated neurotrophic factors like TGF-β.
• HCSS-50 conduits combined with bone marrow mesenchymal stem cell-derived Schwann cells promoted axonal regeneration and upregulated key nerve regeneration markers (Krox20, Zeb2, GAP43).

Conclusions:

• Hydroxypropyl chitosan/soy protein isolate composite sponges (HCSS) demonstrate excellent physicochemical properties and biocompatibility.
• HCSS-50 is a promising material for peripheral nerve regeneration, enhancing cell proliferation and neurotrophic factor expression.
• Engineered nerve conduits using HCSS-50 and Schwann cells offer a viable strategy for peripheral nerve repair.