Hydrogen plays a protective role in intestinal injury of mice with severe sepsis by regulating the release of heme oxygenase-1 and high mobility group protein B1

Results: The 7-day survival rate of WT and Nrf2-KO mice in CLP group was zero; in WT mice, the 7-day survival rate of CLP+H2 group was significantly higher than that of CLP group (45% vs. 0%, P 0.05). Compared with Sham group, the CFU in the PLF of both mice in CLP group increased significantly. Compared with CLP group, 2% H2 treatment could significantly improve the bacterial clearance rate of WT mice with severe sepsis (CFU, ×103: 34.7±6.3 vs. 74.2±8.1, P 0.05). The results of Western blotting, immunohistochemical and immune-fluorescence showed that the expression of HO-1 and HMGB1 in the CLP group were higher than those in the Sham group. Compared with CLP group, the expression of HO-1 in WT mice of CLP+H2 group was significantly higher [HO-1 protein expression (HO-1/β-actin): 0.716±0.035 vs. 0.460±0.045, HO-1 positive expression (A value): 0.703±0.135 vs. 0.430±0.116, both P < 0.01], while the expression of HMGB1 was significantly lower [HMGB1 protein expression (HMGB1/β-actin): 0.052±0.038 vs. 0.082±0.008, HMGB1 positive expression (A value): 24.530±9.317 vs. 41.830±2.458, both P 0.05]. Conclusions: H2 can inhibit the intestinal injury of mice with severe sepsis through Nrf2/HO-1/HMGB1 pathway, and Nrf2 plays an important role in the treatment of intestinal injury with H2.