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World J Gastrointest Pharmacol Ther. Aug 6, 2016; 7(3): 353-360
Published online Aug 6, 2016. doi: 10.4292/wjgpt.v7.i3.353
Overview of cytokines and nitric oxide involvement in immuno-pathogenesis of inflammatory bowel diseases
Imene Soufli, Ryma Toumi, Hayet Rafa, Chafia Touil-Boukoffa
Imene Soufli, Ryma Toumi, Hayet Rafa, Chafia Touil-Boukoffa, Department of Cellular and Molecular Biology, University of Sciences and Technology Houari Boumediene, 16111 Algiers, Algeria
Author contributions: Soufli I analyzed the literature, wrote, submitted and edited the manuscript; Toumi R and Touil-Boukoffa C analyzed the literature and wrote the manuscript; Rafa H analysed and wrote a part of the manuscript.
Conflict-of-interest statement: The authors have no conflict of interest to report.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Chafia Touil-Boukoffa, Professor, Department of Cellular and Molecular Biology, University of Sciences and Technology Houari Boumediene, El alia, Bab Ezzouar, BP 32, 16111 Algiers, Algeria. touilboukoffa@yahoo.fr
Telephone: +213-550-819857
Received: March 29, 2016
Peer-review started: April 5, 2016
First decision: May 23, 2016
Revised: June 10, 2016
Accepted: July 14, 2016
Article in press: July 18, 2016
Published online: August 6, 2016
Processing time: 125 Days and 2 Hours
Abstract

Inflammatory bowel diseases (IBDs), including Crohn’s disease and ulcerative colitis are complex disorders with undetermined etiology. Several hypotheses suggest that IBDs result from an abnormal immune response against endogenous flora and luminal antigens in genetically susceptible individuals. The dysfunction of the mucosal immune response is implicated in the pathogenesis of IBD. The balance between pro-inflammatory cytokines [tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-8, and IL-17A], anti-inflammatory cytokines (IL-4 and IL-13), and immunoregulatory cytokines (IL-10 and transforming growth factors β) is disturbed. Moreover, evidence from animal and clinical studies demonstrate a positive correlation between an increased concentration of nitric oxide (NO) and the severity of the disease. Interestingly, proinflammatory cytokines are involved in the up-regulation of inducible oxide synthase (iNOS) expression in IBD. However, anti-inflammatory and immunoregulatory cytokines are responsible for the negative regulation of iNOS. A positive correlation between NO production and increased pro-inflammatory cytokine levels (TNF-α, IL-6, IL-17, IL-12, and interferon-γ) were reported in patients with IBD. This review focuses on the role of cytokines in intestinal inflammation and their relationship with NO in IBD.

Keywords: Inflammatory bowel disease; Cytokines; Nitric oxide; Inducible nitric oxide synthase; Immuno-pathogenesis

Core tip: Inflammatory bowel diseases (IBDs), including Crohn’s disease and ulcerative colitis are an immunolgically mediated disease with undetermined etiology. Evidence from animal and clinical studies demonstrate a positive correlation between an increased concentration of nitric oxide (NO) and the severity of the disease. Moreover, a positive correlation between NO production and increased pro-inflammatory cytokine levels [tumor necrosis factor-α, interleukin (IL)-6, IL-17, IL-12, and interferon-γ] were reported in patients with IBD. This review focuses on the role of cytokines in intestinal inflammation and their relationship with NO in IBD.