Fig. 5

Blocking CD40L-CD40-TRAF6 signaling pathway improved intestinal barrier function in septic mice. Compound 6,877,002 (10 μmol/kg) was injected intraperitoneally 2 h prior to and at 12 h after CLP to block the CD40-TRAF6 signaling pathway. 24 h after CLP, mice were sacrificed, and tissue samples were collected. a The survival percentage of the mice was investigated within 7 days after CLP by survival curves (n = 10). Intestinal barrier permeability was indicated by serum FITC-Dextran levels (b) (n = 6), water content (c) of gut (n = 6), and colony-forming units (CFUs) (d–f) from mesenteric lymph node (MLN), liver and lung (n = 6). g, h Haematoxylin and eosin (H&E) staining and pathological score, Scale bar = 100 μm (n = 6). i, j Western blot analysis of ZO-1 and occludin expression (n = 6). k, l TNF-α and IL-1β levels in intestinal tissues (n = 6). m, n Immunofluorescence staining analysis of ZO-1 (red), Scale bar = 50 μm (n = 6). The data are presented as the mean ± SEM, *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001