[Researches on the change of intestinal barrier function in patients with ulcerative colitis]

To discuss the variation of intestinal barrier and its clinical significance in patients with ulcerative colitis (UC).

Specimens were obtained from 200 patients of UC and 40 controls respectively from March 2010 to June 2013. UC samples were classified into three groups as mild (n = 68), moderate (n = 70) and severe (n = 62) according to Mayo classification. Immunohistochemistry was performed to examine the expression of occludin, β-defensin and sIgA, which respectively reflect the changes of mechanical barrier, chemical barrier and immune barrier in intestinal tissue. The result and the clinical data were analyzed.

Compared with controls, the expression of occludin and sIgA significantly decreased (28.53% ± 2.21% vs 44.28% ± 1.94%, 19.26% ± 1.09% vs 28.36% ± 2.36%, both P < 0.05), β-defensin significantly increased (29.13% ± 1.75% vs 19.71% ± 1.83%, P < 0.05) in UC group. There was a significant difference of occludin levels among different active subgroups (P < 0.05), and the levels decreased significantly with the increase of UC classification (r = -0.753, P < 0.05). β-defensin levels were significant differently among different active subgroups (P < 0.05), and the levels increased significantly with the increase of UC classification (r = 0.698, P < 0.05). There was no significant difference in the sIgA levels among the three stages (P > 0.05). In different gender, age and lesion site, there was no statistically significant difference in expression of three kinds of protein (all P > 0.05).

UC patients exist intestinal barrier function injury, with the increase of UC classification, the damages of intestinal mechanical barrier and chemical barrier were more obvious.