Novel Thermosensitive Hydrogel Promotes Spinal Cord Repair by Regulating Mitochondrial Function

Area of Science:

• Regenerative Medicine
• Neuroscience
• Biomaterials Science

Background:

• Spinal cord injury (SCI) impairs mitochondrial function, leading to neuronal apoptosis and hindering recovery.
• Innovative therapies are crucial for addressing the clinical challenges of SCI.
• Mitochondrial dysfunction is a key factor in SCI-induced neuronal damage.

Purpose of the Study:

• To develop and evaluate a novel polymer bioactive system for SCI treatment.
• To investigate the therapeutic effects of a hydrogel combining umbilical cord mesenchymal stem cells (UCMSC) and basic fibroblast growth factor (bFGF).
• To elucidate the molecular mechanisms underlying the hydrogel's protective effects on mitochondrial function.

Main Methods:

• UCMSC and bFGF were immobilized in an extracellular matrix (ECM) and heparin-poloxamer (HP) hydrogel.
• The UCMSC-bFGF-ECM-HP hydrogel's efficacy was assessed using in vitro and in vivo models of SCI.
• Molecular mechanisms involving p21-activated kinase 1 (PAK1) and mitochondrial sirtuin 4 (SIRT4) were investigated.

Main Results:

• The UCMSC-bFGF-ECM-HP hydrogel demonstrated significant therapeutic effects in SCI models.
• The hydrogel reduced neuronal apoptosis and improved mitochondrial function by promoting fusion and reducing fragmentation.
• Key molecular pathways involving PAK1 and SIRT4 activation were identified as crucial for the observed protective effects.

Conclusions:

• The developed hydrogel shows promise for treating SCI by restoring mitochondrial function and reducing apoptosis.
• The study highlights the potential of stem cell-based scaffolds combined with growth factors for nerve regeneration.
• Targeting PAK1 and SIRT4 offers potential therapeutic strategies for SCI treatment.