Caudal optogenetic spinal stimulation promotes better therapeutic outcomes than rostral optogenetic stimulation following a cervical spinal cord injury
Year: 2026
Type: article
Abstract: Purpose Spinal stimulation, including optogenetic stimulation, is a promising therapeutic approach for promoting functional recovery after spinal cord injury (SCI). To date, most studies have delivered stimulation caudal to the level of the lesion. Therefore, there is a lack of understanding of how spinal stimulation rostral to the lesion may affect recovery. Here, we investigate the effects of optogenetic spinal stimulation rostral to the lesion site on forelimb functional recovery and axonal growth in a rat model of cervical SCI. Methods Female Long-Evans rats received a C4 hemicontusion, intraspinal injections of an optogenetic viral vector rostral to the injury site, and a micro-light-emitting diode (μLED) implant for optogenetic stimulation. Beginning 6 weeks post-injury, rats received 6 weeks of optogenetic or sham stimulation alongside forelimb reaching rehabilitation. Forelimb reaching success and growth-associated protein 43 (GAP43) percent area were compared with those in our previous study, which evaluated an identical paradigm, but with optogenetic stimulation positioned caudal to the injury. Results The present results indicate that rostral stimulation did not enhance forelimb recovery on the forelimb reaching task and that forelimb reaching success was significantly higher in the caudal optogenetic stimulation group compared to the rostral stimulation group. Additionally, rostral stimulation did not enhance axonal growth within the cervical spinal cord compared with sham stimulation, whereas caudal optogenetic stimulation promoted significantly more axonal growth than rostral optogenetic stimulation. Conclusion Overall, these results indicate that caudal optogenetic stimulation promotes a greater therapeutic impact than rostral optogenetic stimulation.
Source: Frontiers in Neuroscience
Institution: University of Washington
Language: English
Topic: Spinal Cord Injury Research
Subfield: Clinical Neurology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,801
OpenAlex ID: W7223052685