VDR Immunohistochemistry Expression Is Down-Regulated in Colorectal Cells of Patients with IBD and Could Rank the Patients According to Their Complications Risk

Abstract

Background: Rising incidence of inflammatory bowel disease (IBD) is an increasing concern among patients of young age worldwide and its most important complication is colitis-associated cancer (CAC). Vitamin D (VD) deficiency is common in IBD and inversely associated with disease activity; meanwhile, vitamin D receptor (VDR) signaling in the gut protects the mucosal epithelial barrier and inhibits inflammation in the colon. This study aims to investigate the connection between VDR expression and IBD in human colorectal tissues. Research design and methods: Using a cross-sectional analysis, this study investigated VDR nuclear immunohistochemistry expression in 35 subjects. The expression level was measured in patients with IBD, and compared with healthy controls (cut off 36.29%). Results: VDR nuclear expression was significantly down-regulated in colorectal tissues of patients with IBD, compared with controls (p = 0.025). Under-expression of VDR was more remarkable in colon cells of patients with UC (p = 0.023). These results confirm the protective role of VD for colonic mucosa in human colon as well, and suggest a benefit from VD supplementation in IBD patients. Conclusions: Our findings add to the body of evidence regarding the positive effect of VD in colorectal mucosal integrity. This study contributes in establishing one of the proposed markers related to disease activity, which can also predict the risk for complications.