Article

Neutrophil-Dependent Oxidative Stress in Ulcerative Colitis

Medical Proteomics, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan.
Journal of Clinical Biochemistry and Nutrition (Impact Factor: 2.29). 08/2007; 41(1):18-26. DOI: 10.3164/jcbn.2007003
Source: PubMed

ABSTRACT Neutrophil accumulation within epithelial crypts and in the intestinal mucosa directly correlates with clinical disease activity and epithelial injury in ulcerative colitis (UC). Current advances have defined the mechanisms by which neutrophils are activated or migrate across mucosal epithelia. A better understanding of this process will likely provide new insights into novel treatment strategies for UC. Especially, activated neutrophils produce reactive oxygen and nitrogen species within intestinal mucosa, which induce oxidative stress. In clinically, we have succeeded to develop a novel granulocytes adsorptive apheresis therapy for UC. In this article, we discuss current advances to define the role of neutrophils-dependent oxidative stress in UC.

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Available from: Yuji Naito, Jul 28, 2015
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    • "Direct measurement of ROS in tissues is difficult because of their short biological half lives [7]. However, direct quantification of ROS levels in colon biopsy specimens from UC patients using chemiluminescence assays showed that ROS levels in these samples are increased compared to those in normal mucosa and positively correlate with disease activities [8] [9] [10] [11]. There is mounting evidence, based on analysis of nitric oxide synthase activity, that there are increased levels of RNM such as NO in inflamed inflammatory bowel disease (IBD) mucosa [12] [13] [14] [15]. "
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