Loss of motor, sensory, and autonomic abilities is a serious neurological disorder known as spinal cord injury (SCI), which frequently results in permanent disability and a substantial economical burden. Secondary damage processes, including neuroinflammation, are crucial in determining disease progression and functional consequences after the original mechanical trauma. Interleukin-6 (IL-6), a pleiotropic cytokine of the gp130 family, has become one of the main mediators of this process and a critical regulator of inflammatory responses following injury. After SCI, the blood-spinal cord barrier (BSCB) is disrupted, allowing peripheral immune cells such as neutrophils, monocytes/macrophages, and lymphocytes to infiltrate while local microglia and astrocytes are quickly activated. Alongside this intricate cellular interaction is a dynamic cytokine milieu where IL-6 signaling plays a role in both harmful and healing processes. IL-6 exacerbates neuronal loss and demyelination by promoting astrocyte reactivity, glial scar formation, and persistent neuroinflammation through activation of the JAK/STAT3 pathway. Simultaneously, IL-6 signaling integrates inflammatory, apoptotic, and survival signals by interacting with important molecular pathways as NF-κB, MAPK, and PI3K/Akt. According to recent research, the post-SCI microenvironment is shaped by oxidative stress regulators like Nrf2 and new types of inflammatory cell death including PANoptosis. Furthermore, the temporal and context-dependent character of inflammation highlights a dual role: whereas later immune regulation may aid in debris removal and tissue healing, early pro-inflammatory responses contribute to tissue damage. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs), biomaterial-based therapies, antioxidants, and therapeutic methods that target IL-6 signaling have demonstrated promise in reducing neuroinflammation and promoting regeneration. In summary, IL-6 is a crucial node in the intricate neuroimmune network of SCI, connecting cellular death pathways, inflammatory signals, and regeneration processes. In order to design targeted and temporally optimized therapeutic approaches for spinal cord injury, a greater comprehension of IL-6-mediated signaling dynamics may offer new insights.
Alper Demirezen (Wed,) studied this question.