Photothermal H₂S generation promotes the function restoration of spinal cord from acute injury

Spinal cord injury (SCI) refers to either a temporary or permanent damage to the spinal cord caused by external forces, which frequently leads to the acute or sustained impairment on the motor and sensory functions of spinal cord and several chronic systemic complications. Current clinical interventions fail to meet the therapeutic needs in a satisfactory way due to the limited efficacy associated with the blood-spinal cord barrier (BSCB). Here, we propose a strategy for the treatment of spinal cord injury (SCI) using a NIR photothermal-controlled release gas nano-generator based on silicene (SNS) nanosheets. This nano gas-generator greatly promotes nerve regeneration attributing to the physiological effects of H₂S, including the inhibition on inflammation and oxidative stress, protections of nerve cells from the injury, promotion of neuron formation and reduction of glial scar formation. The results show that H₂S-generator is capable of reducing the expressions of activated microglia macrophages and pro-inflammatory cytokines via the NF-κB pathway in SCI mice, which significantly promotes the axon regeneration and functional recovery after SCI. The sustained effectiveness of the generator in the repair of SCI offers a promising prospect in the treatments of a range of neuro-degenerations in addition to spinal cord injury, such as Parkinson's disease and Alzheimer's disease.