Dynamic Changes of IL-17, occludin, and ZO-1 in Mice with Post-infectious Irritable Bowel Syndrome / 中山大学学报(医学科学版)

ABSTRACT

[Objective] To observe the dynamic changes of intestinal IL-17,occludin,and ZO-1 in mice with postinfectious irritable bowel syndrome (PI-IBS).[Methods] Forty C57BL/6 mice were randomly divided into 5 groupscontrol group and infection groups (2 weeks,4 weeks,6 weeks,and 8 weeks after trichinella infection).Infection groups were given by gavaging of 400～500 Trichinella spiralis in 0.2 mL of normal saline.The body weight of mice were recorded at week 2,4,6,and 8 after infection.The visceral sensitivity of mice was measured by the abdominal withdrawal reflex (AWR).The stool was collected continuously for 8 hours to calculate the percentage of fecal water content.Pathological changes of gut were observed by HE staining.The expressions of IL-17,occludin,and ZO-1 in ileocecus and colon were detected by immunohistochemistry and Western blotting.[Results] At week 2 after infection,the acute inflammation of the intestinal tract was observed and the body weight of mice were significantly decreased (P=0.000).Until week 8 after infection,the intestinal inflammation and body weight of mice recovered to normal.When the colorectal dilatation capacity was 0.35 and 0.5 mL,the AWR scores in the infection groups were significantly higher than those in the control group (P＜0.01).The percentages of fecal water content in the infection groups were significantly higher than those in the control group (P＜0.05).Compared with the control group,the expressions of IL-17 were significantly decreased in week 2 group (P＜0.05) and increased in week 8 group (P＜0.05).The expressions of occludin and ZO-1 in the infection groups were significantly lower than those in the control group (P＜0.05).[Conclusion] The dynamic changes of IL-17 and the decrease of Tight junction proteins may be one of the mechanisms of visceral hypersensitivity and increased percentages of fecal water content.They may be involved in the development of PI-IBS.