The Research On Alteration Of Intestinal Barrier In Ulcerative Colitis

ObjectiveUlcerative colitis is a non-specific inflammatory bowel disease where pathological changes primarily attack the mucosa and the sub-mucosa of rectum and colon. The research study is to detect variation of intestinal mucosal barrier in the patients with ulcerative colitis, explore the pathogenesis and clinical significance relation between intestinal barrier and ulcerative colitis, understanding the disease in further stage and depth of its pathogenesis and a more meaningful basis for clinical therapy.MethodsThis study is divided into two parts.The first part:Wax block samples from group of 200 patients were collected from the department of endoscopy in Tianjin Medical University, who were diagnosed with Ulcerative Colitis and underwent the Colonoscopy. The samples were classified into three groups as mild, moderate and severe according to Truelove classification. Meanwhile control group of 20 patient's intestinal tissue samples with non-ulcerative colitis was taken, who went operation in Tianjin Medical University. In order to research the change of mechanical barriers, chemical barriers and changes in the immune barrer, immunohistochemistry was used to examine the expression of occluding,β-defensin, sIgA in Intestinal tissue.The second part:Twenty one Intestinal tissue samples of the Intractable Ulcerative Colitis (IUC) patients who were operated in Tianjin General Hospital were taken and divided into two groups according to the Truelove classification:moderate and severe groups. The control groups were same as the first part. To research the change of the intestinal mucosa barrier in Intractable Ulcerative Colitis, immunohistochemistry was used to examine the expression of occluding andβ-defensin, and RT-PCR was used to examine the expression of TNF-a and IL-13 at the level of mRNA.Results1. It was shown by immunohistoehemistry that the expression of occluding, and sIgA in the colonic mucosa of UC was significantly lower than that in the normal colonic mucosa(P<0.05), and the expression ofβ-defensin was higher than the control. The difference was statistically significant (P<0.05).2. The difference of occluding,β-defensin among the three classification was statistically significant (P<0.05). But no significant difference of sIgA was found among the three classification (P>0.05), meantime the difference of the three index in different sex, age and lesion site were not statistically significant (P>0.05).3. In the protein level, The expression of occludin and P-defensin between different degree were statistically significant (P<0.05), but the expression of the same degree between UC and IUC were not statistically significant.(P>0.05)4. On the mRNA level, the expression of TNF-amRNA in IUC was higher than control, the expression of IL-13mRNA lower than control, the expression between different degree were statistically significant (P<0.05).The expression of TNF-amRNA and IL-13mRNA in the same IUC does not correlate.ConclusionThe expression of occludin and sIgA in UC were reduced, it shows that UC destroys the mechanical barriers and immune barrier of intestinal canal. In addition, the change of occludin is concerned with the degree of UC. These indexes can become the indicator for determining the severity of UC. The expression ofβ-defensin in UC was raised and the change is related with the degree of UC, which indicates thatβ-defensin plays an important role in UC. On the mRNA level, the expression of TNF-amRNA in IUC was higher than control and the expression of IL-13mRNA was lower than control which shows that the two cytokines join the inflammatory response in UC.