Fig. 4

HO-1 protects spinal cord neurons from NLRP1 inflammasome-induced neuronal death. a H₂O₂ induced NLRP1 expression in primary spinal cord neurons after 6-h treatment. Left panel: representative immunoblot image. Right panel: statistical analysis for inflammasome components. Un: untreated control. b Association of NLRP1 with ASC and caspase-1 was determined by co-immunoprecipitation after 6-h H₂O₂ treatment. Un: untreated control. c HO-1 inhibited NLRP1 expression after H₂O₂ treatment. Primary neurons were transduced with A-HO-1 or transfected with HO-1 siRNA. Twenty four hours later, neurons were treated with H₂O₂ for additional 6 h. Expression of HO-1 and NLRP1 was determined by immunoblot. This is a representative image of four independent experiments. C: cells under transduction or transfection condition without AAV and siRNA. Si-HO-1: HO-1 siRNA. d Statistical analysis for the expression of HO-1 and NLRP1 in c. *p < 0.05; ***p < 0.001 compared with “C” group. e Expression of pro-caspase-1 and caspase-1 p20 in H₂O₂-treated primary neurons. Un: untreated control. C: cells under transduction or transfection condition without AAV and siRNA. Si-HO-1: HO-1 siRNA. f Representative images of TUNEL staining after 12-h H₂O₂ treatment. Un: untreated control. C: cells under transduction or transfection condition without AAV and siRNA. Si-HO-1: HO-1 siRNA. Si-NLRP1: NLRP1 siRNA. g Statistical analysis for TUNEL. N = 6 per group. *p < 0.05; **p < 0.01; ***p < 0.001