Satellite Glial Cells in Peripheral Nerve Injury and Regeneration

Satellite glial cells (SGCs) are morphologically unique peripheral glial cells that surround neuronal somas in sensory, sympathetic, and parasympathetic ganglia. Satellite glial cells communicate with neurons that they ensheathe and form a distinct structural and functional unit. Following peripheral nerve injury, satellite glial cells undergo remarkable morphological changes, including gliosis, and help regulate the microenvironment surrounding neuronal somas. The expression of many satellite glial cell markers such as glial fibrillary acidic protein (GFAP) and connexin-43, pro-inflammatory cytokines, and growth factors in satellite glial cells is altered in these cells. Injury responses of satellite glial cells, particularly the activation of peroxisome proliferator-activated receptor α (PPARα), contribute to enhanced axonal regeneration. Targeting satellite glial cells may therefore offer novel therapeutic strategies for the treatment of peripheral nerve injury.