a Structure of 1,2,3-TTB. b, c iBMDMs pretreated with LPS were treated with 1,2,4-TTB/Nig or 1,2,3-TTB/Nig for 1 h, and the cells and supernatants were harvested for analysis of cleaved IL-1β and cleaved Casp-1 expression by Western blotting (b). The gray values of the cleaved IL-1β (c) and cleaved Casp-1 (d) bands were analyzed with ImageJ. e–g Primary macrophages pretreated with LPS were treated with 1,2,4-TTB/Nig or 1,2,3-TTB/Nig for 45 min, and the cells and supernatants were harvested for analysis of the expression of cleaved IL-1β and cleaved Casp-1 by Western blotting (e). The gray values of the cleaved IL-1β (f) and cleaved Casp-1 (g) bands were analyzed with ImageJ. h Primary macrophages pretreated with LPS were treated with 1,2,4-TTB/Nig or 1,2,3-TTB/Nig for 45 min, and the cells and supernatants were harvested for analysis of the expression of cleaved IL-1β by ELISA. (* indicates P < 0.05, ** indicates P < 0.01 by one-way ANOVA).