Objective: To explore the mechanisms of emodin in protecting intestinal mucosal barrier in rat with severe acute pancreatitis (SAP).
Methods: Sixty SD rats were randomly divided into three groups: sham-operation group, untreated group, and emodin group. SAP in rats of the untreated group and the emodin group was induced by retrograde pumping of 3.0% sodium cholate to the common bile duct. Specimens were obtained 24 hours after the severe acute pancreatitis was induced. Serum level of leptin, serum activity of amylase and plasma content of endotoxin were measured. Ileum mucosa from ileocecal junction was observed by light microscopy and electron microscopy to measure pathological and ultrastructural changes. Apoptosis of ileum mucosal cells was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling method, and expression of Bax in ileum mucosal cells was measured by immunohistochemical method.
Results: Compared with the sham-operation group, there was significant increase in the levels of leptin, endotoxin, the activity of amylase, apoptosis index and Bax expression in the untreated group (P<0.01). Compared with the untreated group, the level of endotoxin, apoptotic index and Bax expression level in the emodin group were significantly reduced (P<0.01) and the leptin level was increased (P<0.05). More severe pathological changes appeared in the untreated group than in the sham-operation group under the light and electron microscopes; meanwhile less severe damage was observed in the emodin group as compared with the untreated group.
Conclusion: Emodin can inhibit the apoptosis of intestinal mucosa cells and up-regulate the serum leptin content to protect the intestina1 barrier function and prevent the translocation of bacteria and endotoxin.