Silk fibroin nanoscaffolds for neural tissue engineering

Area of Science:

• Biomaterials Science
• Neural Engineering
• Regenerative Medicine

Background:

• Nervous system damage poses significant health risks due to limited regeneration capacity.
• Neural engineering seeks methods to stimulate repair in complex neural tissues.
• Developing biomaterials for central nervous system (CNS) regeneration is a critical challenge.

Purpose of the Study:

• To fabricate and characterize three-dimensional nanoscaffolds (3DNSs) for neural tissue regeneration.
• To evaluate the in vitro biological activity and in vivo effects of 3DNSs on reactive astrogliosis post-stroke.
• To investigate the influence of silk fibroin (SF) concentration on 3DNS properties and biological response.

Main Methods:

• Electrospinning of silk fibroin (SF), polyethylene glycol (PEG), and polyvinyl alcohol (PVA) to create 3DNSs.
• Characterization of 3DNS mechanical properties and internal structure based on SF concentration.
• In vitro assessment of 3DNSs using PC12 cells for viability.
• In vivo evaluation of 3DNSs in a photothrombotic stroke model in mice, assessing glial fibrillary acidic protein (GFAP) expression.

Main Results:

• SF concentration determined 3DNS morphology, yielding gel-like (SF ≥ 50%) or nanofibrous (SF ≤ 40%) structures.
• In vitro studies showed increased PC12 cell viability with 3DNSs.
• In vivo studies demonstrated a significant reduction in GFAP expression in the peri-infarct region, indicating suppressed reactive astrogliosis.
• The 3DNS formulations (F2 and F4) significantly impacted GFAP levels post-stroke.

Conclusions:

• The developed SF/PEG/PVA 3DNSs exhibit tunable mechanical and structural properties.
• 3DNSs promote neural cell viability in vitro and suppress reactive astrogliosis in vivo.
• These nanoscaffolds represent a promising therapeutic strategy for stroke recovery, potentially enhanced with drug or cell therapies.