Brilliant Blue G Inhibits Inflammasome Activation and Reduces Disruption of Blood–Spinal Cord Barrier Induced by Spinal Cord Injury in Rats

BACKGROUND: Brilliant blue G (BBG) is a P2X7 receptor inhibitor that has been reported to improve spinal cord injury (SCI) in previous studies, but the specific mechanism has been unclear. In this study, we investigated the effects of BBG on inflammasomes and blood–spinal cord barrier (BSCB) permeability after SCI. MATERIAL/METHODS: The experimental rats were randomly divided into 3 groups: sham, SCI, and SCI+BBG. The expression of P2X7 and inflammasome-related proteins was measured by Western blot and immunohistochemistry, while IL-1β and IL-18 levels were measured by using an enzyme-linked immunosorbent assay (ELISA) kit. The permeability of the BSCB was evaluated by Evans Blue (EB) exosmosis, and histological alterations were observed by hematoxylin-eosin staining. Motor function recovery was assessed by the Basso, Beattie, Bresnahan (BBB) scale after SCI. RESULTS: The expression levels of P2X7, NLRP3, ASC, cleaved XIAP, caspase-1, caspase-11, IL-1β, and IL-18 were increased significantly after SCI, and BBG administration inhibited this increase at 72 h after SCI. BBG administration significantly reduced EB leakage at 24 h after SCI. Furthermore, treatment with BBG significantly attenuated histological alterations and improved motor function recovery after SCI. CONCLUSIONS: BBG administration promoted motor function recovery and alleviated tissue injury, and these effects might be related to the suppression of inflammasomes and the maintenance of BSCB integrity.