Expressions and Significance of CXC Chemokine Receptor Type 2 and Interleukin-8 in Patients with Inflammatory Bowel Disease / 胃肠病学

ABSTRACT

Background:CXC chemokine receptor type 2(CXCR2)is a member of G protein coupled receptor superfamily,and is mainly involved in the growth of tumor,angiogenesis and the pathogenesis of inflammatory diseases. Studies showed that CXCR2 was associated with the pathogenesis of inflammatory bowel disease(IBD),but the exact role has not yet been clarified. It was found that the interaction of interleukin-8(IL-8)with CXCR1 and CXCR2 played an important role in the pathogenesis of IBD. Aims:To investigate the expressions and significance of CXCR2 and IL-8 in patients with IBD. Methods:A total of 121 IBD patients in active stage from October 2013 to December 2014 at Zhongnan Hospital of Wuhan University were enrolled and assigned into Crohn’s disease(CD)group and ulcerative colitis(UC)group. Seventy healthy subjects were served as controls(HC). Expressions of IL-8 mRNA and CXCR2 mRNA in peripheral blood and intestinal mucosal tissue were determined by real-time PCR;expression of CXCR2 protein in intestinal mucosal tissue was determined by Western blotting. Results:In peripheral blood,expression of IL-8 mRNA in UC group was significantly higher than that in HC group(P = 0. 017),while expressions of CXCR2 mRNA in CD,UC and HC groups were not significantly different (P = 0. 285). In intestinal mucosal tissue,expressions of IL-8 mRNA in CD,UC and HC groups showed no significant difference(P = 0. 206),while expressions of CXCR2 mRNA in CD and UC groups were significantly higher than that in HC group(P = 0. 002;P < 0. 001),and expression of CXCR2 mRNA in UC group was significantly higher than that in CD group(P = 0. 005);expressions of CXCR2 protein in UC and CD groups were higher than that in HC group(P = 0. 049 P =0. 080). Conclusions:Expressions of CXCR2 mRNA and protein in intestinal mucosal tissue of patients with IBD, especially UC are significantly increased. Down regulation of CXCR2 expression in intestinal mucosa may provide a new target for treatment of UC. IL-8 is significantly highly expressed in peripheral blood of patients with UC,which suggests that IL-8 might be related mainly with UC.