Glycoprotein Injectable Hydrogels Promote Accelerated Bone Regeneration through Angiogenesis and Innervation

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Biochemistry

Background:

• Glycoproteins, particularly mucin, are emerging as versatile biomaterials.
• Mucin's role in bone mass and mineralization is known, but its structure limits biomaterial applications.
• Understanding mucin's structure-property relationship is crucial for its development as a bone regeneration scaffold.

Purpose of the Study:

• To develop a glycoprotein mucin-based thermosensitive hydrogel for bone regeneration.
• To investigate the efficacy of this hydrogel in promoting bone healing, angiogenesis, and innervation.
• To explore mucin's role in extracellular matrix formation.

Main Methods:

• Development of a thermosensitive hydrogel using Poly (N-isopropyl acrylamide)-modified mucin and collagen.
• Characterization of the hydrogel's structure and mechanical properties.
• In vivo implantation in rat calvarial defects to assess bone regeneration, angiogenesis, and innervation via molecular markers.

Main Results:

• The developed hydrogel exhibited a porous structure and mechanical strength.
• Significant new bone tissue formation was observed at 8 weeks post-implantation.
• Upregulation of angiopoietin (bone healing), neurofilament heavy chain (nerve regeneration), and osteoadherin/osteocalcin (bone formation) was detected.

Conclusions:

• The thermosensitive injectable hydrogel based on glycoprotein mucin is a promising biodegradable biomaterial for bone regeneration.
• The hydrogel effectively accelerates repair and healing in calvarial bone defects.
• Promoting angiogenesis and innervation are key mechanisms by which the hydrogel facilitates bone regeneration.