Gsx1 Promotes Locomotor Functional Recovery After Spinal Cord Injury

Promoting residential cells, particularly endogenous neural stem and progenitor cells (NSPCs), for tissue regeneration represents a potential strategy for the treatment of spinal cord injury (SCI). However, adult NSPCs differentiate mainly into glial cells and contribute to glial scar formation at the site of injury. Gsx1 is known to regulate the generation of excitatory and inhibitory interneurons during embryonic development of the spinal cord. Here we show that lentivirus-mediated expression of Gsx1 increases the number of NSPCs in a mouse model of lateral hemisection SCI during the acute stage. Subsequently, Gsx1 expression increases the generation of glutamatergic and cholinergic interneurons and decreases the generation of GABAergic interneurons in the chronic stage of SCI. Importantly, Gsx1 reduces reactive astrogliosis and glial scar formation, promotes 5-HT neuronal activity, and improves the locomotor function of the injured mice. Moreover, RNA-seq analysis reveals that Gsx1-induced transcriptome regulation correlates with NSPC signaling, NSPC activation, neuronal differentiation, and inhibition of astrogliosis and scar formation. Collectively, our study provides molecular insights for Gsx1-mediated functional recovery and identifies Gsx1 gene regulation as a potential application for injuries in the spinal cord and possibly other parts of the central nervous system. Overall design: Spinal cord tissues of 3, 14, 35 days post-injury (DPI) were isolated and segments containing injured/injected (parenchymal segments spanning ~2-3 mm from each side of the lesion) were rapidly snap-frozen in liquid nitrogen. Total RNA was isolated from spinal cord tissues using the RNeasy Lipid Tissue Mini kit (Qiagen, #74804) following the manufacturer's protocol. The concentration of the total RNA was determined using Qubit RNA BR Assay Kit (Life Technologies) and quality of the total RNA was determined using the RNA 6000 Nano chip on the 2100 Bioanalyzer automated electrophoresis system (Agilent Technologies).