Role of cytokines in inflammatory bowel disease

Abstract

Inflammatory bowel disease (IBD), which includes Crohn's disease (CD) and ulcerative colitis (UC), represents a group of chronic disorders characterized by inflammation of the gastrointestinal tract, typically with a relapsing and remitting clinical course. Mucosal macrophages play an important role in the mucosal immune system, and an increase in the number of newly recruited monocytes and activated macrophages has been noted in the inflamed gut of patients with IBD. Activated macrophages are thought to be major contributors to the production of inflammatory cytokines in the gut, and imbalance of cytokines is contributing to the pathogenesis of IBD. The intestinal inflammation in IBD is controlled by a complex interplay of innate and adaptive immune mechanisms. Cytokines play a key role in IBD that determine T cell differentiation of Th1, Th2, T regulatory and newly described Th17 cells. Cytokines levels in time and space orchestrate the development, recurrence and exacerbation of the inflammatory process in IBD. Therefore, several cytokine therapies have been developed and tested for the treatment of IBD patients.

A Novel Mouse Model of Inflammatory Bowel Disease Links Mammalian Target of Rapamycin-Dependent Hyperproliferation of Colonic Epithelium to Inflammation-Associated Tumorigenesis

“…Inflammatory macrophages are known to produce an array of cytokines and chemokines that promote infiltration and activation of other leukocytes, including lymphocytes, and that also promote angiogenesis, cell proliferation, and tissue damage. 43,44 However, unlike IL-10 Ϫ/Ϫ mice, in which malignant tumors develop in the inflamed intestine, 9 no tumors were reported in mice with LysM-or Mx1-Cre-mediated Stat3 inactivation in myeloid cells. In contrast, we demonstrate the development of malignancy in Stat3-IKO mice, suggesting that Stat3 in both myeloid and lymphoid cells may serve as a control point for the development of malignant intestinal tumors.…”

Dietary phenylalanine-improved intestinal barrier health in young grass carp (Ctenopharyngodon idella) is associated with increased immune status and regulated gene expression of cytokines, tight junction proteins, antioxidant enzymes and related signalling molecules

“…The effects of Phe on cytokine expression are likely due to Phe affect the proliferation of immune cells. In human, lymphocytes can secret IL-10 and TGF-b [53]. Chuang et al [54] reported that Phe is essential for lymphocyte proliferation in humans.…”

Omega 3 fatty acids supplementation has an ameliorative effect in experimental ulcerative colitis despite increased colonic neutrophil infiltration

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