Proteomics reveals the effect of low-intensity focused ultrasound on spasticity after spinal cord injury

To explore the efficacy and possible mechanisms of Low-intensity focused ultrasound (LIFU) in alleviating spasticity caused by Spinal cord injury (SCI).We selected male Sprague?Dawley rats as subjects and performed transverse injuries on the T9 vertebra of their spinal cord (SC) to build SCI. On the 7th day after SCI, LIFU treatment was performed below the SCI segment once a day for 20 min, for 4 consecutive weeks. During treatment, a pressure sensor was used to assess the degree of spasticity. After treatment, the SC tissues from the treatment sites of the SCI+LIFU(-) and SCI+LIFU(+) groups were extracted, and high-throughput sequencing was performed to identify the changes in proteomics. In addition, expression of the growth associated protein 43 (Gap43) was validated by western blotting.The behavioral results suggested that after 2 weeks of SCI, the rats were significantly induced to have a spastic reaction (p < 0.05), while after 4 weeks of LIFU treatment, the spastic response of rats was significantly improved (p < 0.05). Western blot analysis showed a significant increase in Gap43 expression in the SCI+LIFU(-) group compared with the sham group, whereas after 4 weeks of LIFU treatment, Gap43 protein expression was significantly decreased (p < 0.05).The results of this study showed that LIFU is an alternative treatment that can effectively relieve spastic reactions caused by SCI, possibly by reducing abnormal neuroplasticity or axon regeneration below the SCI segment.