Role of nucleotide oligomerization domain 2-related intestinal barrier injury in ileum pouch inflammation / 中华消化杂志

ABSTRACT

Objective:To observe and analyze the function of intestinal barrier in patients with pouchitis, and to explore the role of nucleotide oligomerization domain 2 (NOD2) in ileal pouchitis, so as to provide new ideas for the pathogenesis of pouchitis.Methods:From January 2011 to December 2016, the clinical pathological data of patients with ileal pouch-anal anastomosis who underwent pouch mucosa biopsy at the Endoscopy Center of General Hospital of Tianjin Medical University were retrospectively analyzed. According to the disease activity index of pouchitis, patients were divided into pouchitis group (20 cases) and non-pouchitis group (30 cases). In addition, UC patients who did not undergo surgery were selected as the control group (10 cases). The intestinal structure of patients of the pouchitis group and non-pouchitis group was observed under transmission electron microscope. The positive expression rates of occludin, alpha human defensin and NOD2 in the control group, non-pouchitis group and pouchitis group were detected and calculated by immunohistochemistry. Levene test, independent sample t test and Spearman correlation analysis were used for statistical analysis. Results:Under the transmission electron microscope, the tight junction epithelial structure and microvilli of intestinal mucosal of patients in the pouchitis group were severely injured. The results of immunohistochemistry showed that the positive expression rates of occludin, alpha human defensin and NOD2 in the intestinal mucosa of patients in the pouchitis group were all lower than those of the control group and non-pouchitis groups ((19.3±0.4)% vs. (84.0±0.3)% and (77.9±0.5)%; (60.0±1.3)% vs. (85.0±0.1)% and (77.3±0.4)%; (46.1±1.6)% vs. (72.0±0.7)% and (60.7±0.5)%), and the differences were statistically significant ( t=-8.451, -7.514, -3.943, -2.970, -5.115 and -2.982, all P<0.05). The correlation analysis showed that the expression level of NOD2 was positively correlated with occludin and alpha human defensin ( r=0.671 and 0.628, both P<0.01). Conclusions:Intestinal barrier function is impaired in patients with ileal pouchitis, and NOD2-related intestinal barrier injury may play an important role in the pathogenesis of ileal pouchitis.