Relationship of intestinal trefoil factor for regulating of nuclear factor-κB and tumor necrosis factor-α and the protective effect of intestinal injury

Abstract

Objective To investigate the relationship of intestinal trefoil factor(ITF) for regulating of nuclear factor(NF)-κB and tumor necrosis factor(TNF)-α and the protective effect of intestinal injury. Methods Twenty-four 10-day Wistar rats were divided into 3 groups: the control group(NS group, n=8), given 9 g/L sodium injection intra-peritoneally, 1 mL/kg; the lipopolysaccharide(LPS) group(n=8), given LPS(5 g/L), 5 mg/kg intraperitoreally; ITF group(n=8), given ITF(5 g/L) 0.1 mL/each plus LPS 5 mg/kg intraperitoreally.Rats were sacrificed 3 hours after injection.A segment of distal ileum was dissected.The pathologic changes of small intestine were observed under the optical microscope(hematoxylin-eosin staining). The expressions of NF-κB mRNA and protein were detected by reverse transcription polymerase chain reaction(RT-PCR), immunohistochemistry, respectively.TNF-α level in intestinal tissues was measured by enzyme linked immunosorbent assay. Results The structure of small intestine in the control group remained normal.The inflammatory cells infiltration and the edema of interstitial substance and epithelium were observed in LPS group and ITF group, while the change in the ITF group was significantly lower than that in LPS group.The expressions of NF-κB mRNA and protein in ITF group were significantly lower than those in LPS group(all P<0.01). The secretion of TNF-α in the ITF group was significantly lower than that in LPS group(P<0.01). Conclusion Protective effects of ITF on intestinal injury are related to the down regulation of NF-κB mRNA and protein expressions and the reduction of the secrete of mediators of inflammation TNF-α. Key words: Intestinal trefoil factor; Nuclear factor-κB; Tumor necrosis factor-α; Intestine