FR167653, a p38 mitogen-activated protein kinase inhibitor, aggravates experimental colitis in mice.

AIM: To investigate the effects of FR167653 on the development of dextran sulfate sodium (DSS)-induced colitis in mice. METHODS: BALB/c mice were fed rodent chow containing 3.5% (wt/wt) DSS. The recipient mice underwent intra-peritoneal injection of vehicles or FR167653 (30 mg/kg per day). The mice were sacrificed on day 14, and the degree of colitis was assessed. Immunohistochemical analyses for CD4(+) T cell and F4/80(+) macrophage infiltration were also performed. Mucosal cytokine expression was analyzed by RT-PCR. RESULTS: The body weight loss was more apparent in the FR167653-treated DSS mice than in the vehicle-treated DSS mice. The colon length was shorter in the FR167653-treated DSS mice than in the vehicle-treated DSS mice. Disease activity index and histological colitis score were significantly higher in FR167653- than in vehicle-treated DSS animals. Microscopically, mucosal edema, cellular infiltration (CD4 T cells and F4/80 macrophages), and the disruption of the epithelium were much more severe in FR167653-treated mice than in controls. Mucosal mRNA expression for interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) were found to be markedly reduced in FR167653-treated DSS mice. CONCLUSION: Treatment with FR167653 aggravated DSS colitis in mice. This effect was accompanied by a reduction of mucosal IL-1beta and TNF-alpha expression, suggesting a role of p38 mitogen-activated protein kinase (MAPK)-mediated proinflammatory cytokine induction in host defense mechanisms.

Acute cytomegalovirus infection superimposed on corticosteroid-naïve ulcerative colitis.

Most cases of cytomegalovirus (CMV) colitis that develop in patients with inflammatory bowel disease (IBD) are caused by a reactivation of a latent virus; acute CMV infections are rare. Treatment with immunosuppressive agents further increases the infection risk. Here, we present a 32-year-old man with acute CMV-mononucleosis and colitis, superimposed on corticosteroid-naïve ulcerative colitis (UC). The diagnosis was confirmed by a viral-like prodrome, positive CMV antigenemia (C7-HRP), a positive CMV IgM titer, the presence of atypical lymphocytes, mild transaminase elevation, and immunohistological detection of CMV positive cells in his colonic mucosa. Gancyclovir was intravenously administered, and all symptoms were improved.

Terminal restriction fragment length polymorphism analysis of the diversity of fecal microbiota in patients with ulcerative colitis.

BACKGROUND: Terminal restriction fragment length polymorphism (T-RFLP) analysis is a powerful tool to assess the diversity of complexed microbiota. This permits rapid comparison of microbiota from many samples. In this study, we performed T-RFLP analysis of the fecal microbiota from patients with ulcerative colitis (UC). METHODS: Forty-four patients with UC (23 women and 21 men, median age 25 years) and 46 healthy individuals (25 women and 21 men, median age 34 years) were enrolled in this study. DNA was extracted from their stool samples, and the 16S rRNA genes were amplified by PCR. The PCR products were then digested with HhaI and/or MspI restriction enzymes, and the length of the T-RF was determined. RESULTS: The fecal microbial communities were classified in 8 clusters. Almost all the healthy individuals (39 of 46) were included in cluster I, and most of the UC patients could be divided into the other 7 clusters, indicating that fecal bacterial communities are different between healthy individuals and active UC patients. Some T-RFs, derived from the unclassified bacteria, Ruminococcus, Eubacterium, Fusobacterium, gammaproteobacteria, unclassified Bacteroides, and unclassified Lactobacillus, were detected in the UC patients, but not in the healthy individuals. The T-RFLP patterns were also different between the active patients and inactive (remission) patients. The T-RF derived from the unclassified bacteria, Ruminococcus and Eubacterium, and the T-RFs derived from the unclassified bacteria, Eubacterium, and Fusobacterium were predominantly detected in the active patients not the inactive patients. In contrast, the T-RFs derived from Lactobacillus and unclassified Lactobacillus were more predominant in the inactive (remission) patients. In 4 patients with proctitis, the pattern of fecal microbial diversity was very similar. CONCLUSIONS: T-RFLP analyses showed that the diversity of fecal microbiota in patients with UC was different from that in healthy individuals. Unclassified bacteria, as well as known bacteria, can contribute to alterations in the bacterial diversity of UC patients.