Curcumin-activated Olfactory Ensheathing Cells Improve Functional Recovery After Spinal Cord Injury by Modulating Microglia Polarization Through APOE/TREM2/NF-κB Signaling Pathway
Journal of Neuroimmune Pharmacology, 2023 · DOI: 10.1007/s11481-023-10081-y · Published: September 2, 2023
Simple Explanation
Spinal cord injury (SCI) often leads to irreversible motor deficits and sensory dysfunction. Neural repair is difficult due to neuron properties and a hostile environment (inflammation, ischemia, hypoxia and glial scars) after SCI. Inflammatory responses greatly contribute to the severity of SCI, making it necessary to develop strategies to regulate pathophysiological processes and improve the microenvironment. Cellular therapy can be an effective option to ameliorate SCI pathologies. This study explores the effects of transplanting curcumin-activated olfactory ensheathing cells (aOECs) on neural regeneration in rats after SCI. The results indicated that aOECs promoted neurological function recovery by shifting microglia from M1 to M2.
Key Findings
- 1CCM-activated OECs effectively attenuated deleterious inflammation by regulating microglia polarization from the pro-inflammatory (M1) to anti-inflammatory (M2) phenotype in SCI rats and facilitated functional recovery after SCI.
- 2Microglial polarization to M2 elicited by aOECs-CM in LPS-induced microglia was effectively reversed when TREM2 expression was downregulated.
- 3CCM-activated OECs could alleviate inflammation after SCI by switching microglial polarization from M1 to M2, which was likely mediated by the APOE/TREM2/NF-κB pathway, and thus ameliorated neurological function.
Research Summary
Practical Implications
Therapeutic Potential
The use of CCM-activated OECs presents a novel therapeutic approach for treating SCI by modulating microglia polarization and reducing inflammation.
Molecular Pathway Targeting
The APOE/TREM2/NF-κB signaling pathway is identified as a key mechanism, suggesting potential targets for pharmacological interventions to enhance recovery after SCI.
Cell-Based Therapy Enhancement
Activating OECs with CCM could improve the efficacy of cell-based therapies for SCI by boosting their anti-inflammatory and neuroprotective functions.
Study Limitations
- 1M1/M2 phenotypes were defined based on classic markers, rather than a broader gene array analysis.
- 2TREM2 may have impacts on other signaling pathways besides NF-κB.
- 3Other transcription factors can also participate in regulating NF-κB activity.