Role of High-Mobility Group Box 1 Protein in the Pathogenesis of Intestinal Barrier Injury in Rats With Severe Acute Pancreatitis

OBJECTIVE: To investigate the role of high-mobility group box 1 (HMGB1) in the development of intestinal barrier injury of severe acute pancreatitis (SAP) and to examine the effect of ethyl pyruvate (EP) on intestinal inflammation in rats with SAP. METHODS: Rats were randomly divided into the following experimental groups: control, SAP, and EP treated. Then, the distal ileum was harvested for morphological studies, streptavidin-peroxidase immunohistochemistry examination, and Western blot analysis. The concentrations of plasma amylase, endotoxin, and diamine oxidase (DAO) and the activity of myeloperoxidase (MPO) in the intestine were determined. RESULTS: We found that the expression of HMGB1 was up-regulated in the ileal mucosa within 6 hours and then remained elevated for more than 48 hours after SAP. Meanwhile, the levels of plasma amylase, endotoxin, and DAO and the activity of MPO in the intestinal mucosa were rapidly increased after SAP. Whereas treatment with EP significantly decreased the expression of intestinal HMGB1, the levels of plasma amylase, endotoxin, and DAO ameliorated the activity of MPO in the intestine in SAP rats. CONCLUSIONS: Our results demonstrate that HMGB1 participates in intestinal barrier injury in SAP and EP might play a therapeutic role in intestinal inflammation in this SAP model.