MicroRNA-activated hydrogel scaffold generated by 3D printing accelerates bone regeneration

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Bone defects present a significant global health challenge, driving demand for effective bone tissue regeneration strategies.
• Combining microRNA (miRNA) therapy with 3D printed scaffolds offers a promising approach to mimic natural bone healing.
• Understanding the interplay between scaffold degradation and miRNA release is crucial for optimizing osteogenesis.

Purpose of the Study:

• To investigate the relationship between scaffold degradation behavior and miRNA release profiles in 3D printed hydrogel scaffolds (MAHSs).
• To determine the optimal balance for enhanced osteoinduction and bone formation.
• To identify suitable scaffolds for accelerated bone regeneration.

Main Methods:

• Fabrication of a series of miRNA-activated hydrogel scaffolds (MAHSs) using 3D printing with varying crosslinking degrees.
• Evaluation of scaffold degradation rates and miR-29b release kinetics.
• Assessment of osteoinductive activity both *in vitro* and *in vivo*.

Main Results:

• Scaffolds with lower crosslinking degraded rapidly, releasing more miRNA but offering insufficient support.
• Scaffolds with higher crosslinking degraded slowly, leading to inadequate miRNA release but better long-term osteoinduction.
• MAHS-1 exhibited the most favorable degradation rate and miR-29b release, promoting accelerated bone regeneration.

Conclusions:

• A bio-adaptable balance between scaffold degradation and bioactive factor release is critical for effective bone regeneration.
• MAHS-1 serves as a preferred scaffold for enhanced bone repair due to its optimized characteristics.
• These findings provide a valuable framework for designing advanced scaffolds for tissue regeneration.