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Synergetic Use of Neural Precursor Cells and Self-assembling Peptides in Experimental Cervical Spinal Cord Injury
Published on: February 23, 2015
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Sustained-Release Spermidine Hydrogel Inhibits M1 Macrophage Polarization and Promotes Tissue Repair for Spinal Cord
Yongjun Luo1, Xiao Zhang2, Qian Luo3
1Department of Orthopedics, The Fourth Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
Biomaterials Research
|September 15, 2025
Summary
This study developed a novel hydrogel delivering spermidine to reduce inflammation and promote nerve repair after spinal cord injury (SCI). The biomaterial enhanced neural integration and locomotor function in a mouse model.
Area of Science:
- Biomaterials Science
- Neuroscience
- Immunology
Background:
- Injectable hydrogels show promise for spinal cord injury (SCI) repair but require optimization.
- Developing cell-free systems with sustained anti-inflammatory properties is crucial for SCI therapeutics.
- Modulating the post-injury immune microenvironment is key to enhancing neural repair.
Purpose of the Study:
- To engineer a biomimetic, cell-free hydrogel system for sustained spermidine release to treat SCI.
- To investigate the hydrogel's capacity to modulate the immune response and promote neural regeneration.
- To evaluate the therapeutic efficacy of the spermidine-loaded hydrogel in a murine SCI model.
Main Methods:
- Fabrication of an aldehyde-modified methacrylated hyaluronic acid (AHAMA) hydrogel via photocrosslinking and Schiff base chemistry.
- Incorporation of spermidine for controlled and prolonged release.
- Assessment of hydrogel properties, including gelation kinetics, mechanical stability, cell-matrix interactions, and immunomodulatory effects (M1 macrophage polarization via STAT1 signaling).
- In vivo evaluation in a murine SCI model to assess neuroregeneration, axonal elongation, and functional recovery.
Main Results:
- The AHAMA hydrogel exhibited rapid gelation and excellent mechanical properties.
- Sustained spermidine release was achieved, enhancing cellular-matrix interactions and neuronal integration.
- The hydrogel suppressed M1 macrophage polarization through STAT1 activation, demonstrating potent immunomodulatory effects.
- In vivo studies showed significant neuroregeneration, axonal growth, and improved locomotor function.
Conclusions:
- The developed spermidine-loaded AHAMA hydrogel is a promising cell-free therapeutic strategy for SCI.
- This approach effectively modulates inflammation and promotes neural repair and functional recovery.
- The combination of a biomimetic scaffold and sustained drug release offers a viable path for advanced SCI treatment.
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