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Purpose: Hyperthermia is known to protect against cellular injury through the expression of heat shock proteins. In this study, the therapeutic effects of hyperthermia on experimental colitis in the rat were evaluated. Materials and methods: Male Wistar rats were given a single intracolonic injection of 2,4,6-trinitrobenzene sulphonic acid (TNBS). Hyperthermia was induced in anesthetized rats by placing them in a temperature-controlled water bath. We started the hyperthermic treatment on the day after the enema. The severity of colitis was evaluated pathologically, and the activities of tissue myeloperoxidase were measured 6 days after the induction of colitis. Furthermore, cytokines, and hyperthermia-induced heat shock proteins in colonic mucosa were detected by enzyme-linked immunosorbent assay and Western blotting. We also investigated the effects of geranylgeranylacetone and zinc protoporphyrin IX on the therapeutic effect of hyperthermia. Results: Hyperthermia significantly improved the macroscopic scores of colitis. The TNBS-induced increases in the activities of myeloperoxidase in the colonic tissue were blunted significantly in hyperthermia-treated animals. Furthermore, hyperthermia attenuated increases in cytokine-induced neutrophil chemoattractants-1 and tumor necrosis factor-α in the colon. Furthermore, hyperthermia induced the production of heat shock proteins in rat colonic mucosa, and the combination of geranylgeranylacetone with hyperthermia further induced the heat shock protein HSP70, which resulted in further improvement of TNBS-induced colitis. On the other hand, the combination of zinc protoporphyrin IX with hyperthermia attenuated the therapeutic effect of hyperthermia. Conclusions: Hyperthermia ameliorates TNBS-induced colitis in rats through the expression of HSP70 and HO-1. It is postulated that hyperthermia may be useful for the treatment of inflammatory bowel diseases. [ABSTRACT FROM AUTHOR]

Aim : The aim of the present study was to explore whether heme oxygenase-1 (HO-1) is involved in the hyperthermia-provided protection of the small intestine from ischemia/reperfusion injury in rats. Methods : Intestinal damage was induced in male Sprague-Dawley rats by clamping both the superior mesenteric artery and the celiac trunk for 30  min, followed by reperfusion. Whole-body hyperthermia was induced in anesthetized rats by placement in a temperature-controlled water bath. Whole-body hyperthermia to a core temperature of 42–43°C for 15  min was followed by passive cooling. We started the hyperthermic treatment 6  h before the vascular clamping. The severity of the mucosal injury was evaluated by several biochemical markers and histological findings. Hyperthermia-induced heat-shock proteins were detected by Western blotting. We also investigated the effect of zinc protoporphyrin IX (an HO-1 inhibitor) on the protective effect of hyperthermia. Results : The rats, which were killed after ischemia/reperfusion, had severe intestinal inflammation. Hyperthermia significantly induced the production of Hsp70 and HO-1 in intestinal mucosa and significantly reduced ischemia/reperfusion-induced mucosal injury. The combination of zinc protoporphyrin IX with hyperthermia extinguished the protective effects of hyperthermia on ischemia/reperfusion injury. Conclusion : Hyperthermia protects against ischemia/reperfusion injury in rat small intestine through the expression of heat-shock proteins, especially HO-1. [ABSTRACT FROM AUTHOR]

This study is designed to test whether the postanoxic endothelial mitochondria is an important source of reactive oxygen species (ROS) using a chemical model of mitochondrial disruption to mimic the loss of mitochondrial integrity after anoxia/reoxygenation (A/R). The current objectives were to (1) determine the adhesion of human neutrophils to human umbilical vein endothelial cells exposed to antimycin A, a specific inhibitor of the mitochondrial cytochrome b–c1 complex, and (2) define the mechanisms responsible for the early and late phases of neutrophil hyperadhesivity. Antimycin A caused a 5-fold increase in ROS generation and induced neutrophil adhesion at 30 min (phase 1) and 4 h (phase 2) that were quantitatively similar to that induced by A/R. Blockade of electron transport in antimycin A and A/R exposed cells with rotenone, amytal or thenoyltrifluoroacetate, but not myxothiazol, prevented neutrophil adhesion, confirming a role for mitochondrial ROS. Catalase inhibited phase 1 adhesion, indicating H2O2 involvement. Anti-ICAM-1 or anti-P-selectin monoclonal antibodies (mAbs) attenuated phase 1 adhesion, while anti-E-selectin mAb attenuated phase 2 adhesion, consistent with roles for constitutive ICAM-1 and preformed P-selectin in early and E-selectin in late phase responses. Actinomycin D and cycloheximide or competing ds-oligonucleotides containing cognate DNA sequences of the nuclear factor κB or activator protein-1 attenuated phase 2 adhesion, implicating a role for de novo protein synthesis. Peak surface expression of the endothelial cell adhesion molecules correlated with peak adhesions at phases 1 and 2. These results show that disruption of mitochondrial respiratory chain elicits ROS production that mediates transcription-independent and -dependent surface expression of various adhesion molecules that leads to a two-phase neutrophil-HUVEC interaction similar to that induced by A/R. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objective: The objectives of this study were to 1) determine the time-course of T-lymphocyte adhesion to monolayers of human umbilical vein endothelial cell (HUVEC) that were exposed to 60 min of anoxia followed by 24 h of reoxygenation, and 2) define the mechanisms responsible for the hyperadhesivity of post-anoxic HUVEC to human T-lymphocytes. Methods: Human peripheral blood mononuclear leukocytes were isolated from heparinized peripheral blood. T-lymphocytes were obtained by negative selection using a MACS column. HUVEC monolayers were exposed to anoxia/ reoxygenation (A/R), and then reacted with [SUP51]Cr -labeled T-lymphocytes in adhesion assays. Results: A/R leads to an increased adhesion of T-lymphocytes to HUVEC monolayers, with peak responses occurring at 8 h after reoxygenation. This adhesion response was largely attributed to the CD4[SUP+] T-cell subset. The hyperadhesivity of A/R-exposed HUVEC was inhibited by monoclonal antibodies directed against either LFA-1, VLA-4, ICAM-1, or VCAM-1, indicating a contribution of these adhesion molecules and their ligands. Moreover, T-cell hyperadhesivity was attenuated by anti- IL-8, consistent with a role for this chemokine in the adhesion response. Protein synthesis inhibitors (actinomycin D and cycloheximide) as well as chemical inhibitors of (and binding ds-oligonucleotides to) NFκB and AP-1 significantly attenuated the A/R-induced T-lymphocyte adhesion responses. The kinetics of VCAM-1 on post-anoxic HUVEC correlated with the T-lymphocyte adhesion response. Conclusions: A/R elicits a T-lymphocyte-endothelial cell adhesion response that involves transcription-dependent surface expression of VCAM- 1. [ABSTRACT FROM AUTHOR]

Background/Aims: To evaluate the usefulness of flexible spectral imaging color enhancement with indigo carmine (I-FICE) in early gastric cancer (EGC) demarcation. Methods: The study participants were 29 patients with differentiated-type EGC. The endoscope was fixed and images of the same area of EGC demarcations in each lesion were obtained using four different methods (WLE, flexible spectral imaging color enhancement (FICE), CE, and I-FICE). FICE mode at R 550 nm (Gain: 2), G 500 nm (Gain: 4), and B 470 nm (Gain: 4) was used. Four endoscopists ranked the images obtained by each method on the basis of the ease of recognition of demarcation using a 4-point system. We calculated the standard deviation of pixel values based on L*, a*, and b* color spaces in the demarcation region (Lab-SD score). Results: The median ranking score for I-FICE images was significantly higher than that obtained from the other methods. Further, the average Lab-SD score was significantly higher for I-FICE images than for images obtained by the other methods. There was a good correlation between the ranking score and Lab-SD score. Conclusion: EGC demarcations were most easily recognized both subjectively and objectively using I-FICE image, followed by CE, FICE and WLE images. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background Recent studies in models of inflammatory bowel disease have demonstrated that heme oxygenase-1 (HO-1) induction, or its by-products in this process such as carbon monoxide (CO), plays an important role in the intestinal inflammation. However, the distribution of HO-1 in intestinal mucosa and the concentration of intestinal luminal CO in humans have not yet been investigated. Aim To detect the HO-immunopositive cells in the intestine of normal subjects and in patients with ulcerative colitis (UC) and to measure intestinal luminal CO gas contents using gas chromatography. Materials and Methods The expression of HO-1 in the intestine was determined using immunohistochemistry. Human colonic gas was collected using colonoscopy from healthy volunteers and patients with UC. Analysis of intestinal luminal gas was performed using a newly developed portable gas chromatograph. Results Immunopositive staining for HO-1 was localized in the inflammatory cells, mainly mononuclear cells, and the number of cells that accepted stain was greater in patients with UC. CO level in the intestinal lumen significantly increased in patients in the active stage of UC. Conclusion These findings indicate that the HO-CO system is induced in UC. [ABSTRACT FROM AUTHOR]

Background Recent reports support the notion that patients with Crohn's disease have a dysregulated innate immune response to endogenous flora. Aim To reveal the distinct gene expression clusters of a lipopolysaccharide-stimulated pathway in the peripheral blood monocytes of Japanese patients with Crohn's disease. Materials and methods Total RNA was extracted from peripheral blood monocytes of four patients in the remission stage of Crohn's disease as well as four controls, and gene expression profiles before and after lipopolysaccharide stimulation were investigated using a high-density oligonucleotide probe array. To focus on innate immunity, the expression of genes to be studied was narrowed down to 118 probe sets which were selected using the following keywords: lipopolysaccharide, toll, myd and tir along with a software of NetAffx Analysis Center. Results Using hierarchical clustering analysis, we picked up to 44 and 36 probe sets for which expression had decreased before and after lipopolysaccharide stimulation, respectively, in patients with Crohn's disease compared with healthy volunteers. The expression of TLR5, 7, MyD88, SIGIRR, and Tollip was decreased both before and after lipopolysaccharide stimulation in patients with Crohn's disease. Conclusion We found several interesting clusters in monocytes before and after stimulation with lipopolysaccharide. These genes may have been responsible for the immunological differences between the Crohn's disease and control patients. [ABSTRACT FROM AUTHOR]

Background Recent studies in models of inflammatory bowel disease have demonstrated that heme oxygenase-1 (HO-1) induction, or its by-products in this process such as carbon monoxide (CO), plays an important role in the intestinal inflammation. However, the distribution of HO-1 in intestinal mucosa and the concentration of intestinal luminal CO in humans have not yet been investigated. Aim To detect the HO-immunopositive cells in the intestine of normal subjects and in patients with ulcerative colitis (UC) and to measure intestinal luminal CO gas contents using gas chromatography. Materials and Methods The expression of HO-1 in the intestine was determined using immunohistochemistry. Human colonic gas was collected using colonoscopy from healthy volunteers and patients with UC. Analysis of intestinal luminal gas was performed using a newly developed portable gas chromatograph. Results Immunopositive staining for HO-1 was localized in the inflammatory cells, mainly mononuclear cells, and the number of cells that accepted stain was greater in patients with UC. CO level in the intestinal lumen significantly increased in patients in the active stage of UC. Conclusion These findings indicate that the HO-CO system is induced in UC. [ABSTRACT FROM AUTHOR]

Background Recent reports support the notion that patients with Crohn's disease have a dysregulated innate immune response to endogenous flora. Aim To reveal the distinct gene expression clusters of a lipopolysaccharide-stimulated pathway in the peripheral blood monocytes of Japanese patients with Crohn's disease. Materials and methods Total RNA was extracted from peripheral blood monocytes of four patients in the remission stage of Crohn's disease as well as four controls, and gene expression profiles before and after lipopolysaccharide stimulation were investigated using a high-density oligonucleotide probe array. To focus on innate immunity, the expression of genes to be studied was narrowed down to 118 probe sets which were selected using the following keywords: lipopolysaccharide, toll, myd and tir along with a software of NetAffx Analysis Center. Results Using hierarchical clustering analysis, we picked up to 44 and 36 probe sets for which expression had decreased before and after lipopolysaccharide stimulation, respectively, in patients with Crohn's disease compared with healthy volunteers. The expression of TLR5, 7, MyD88, SIGIRR, and Tollip was decreased both before and after lipopolysaccharide stimulation in patients with Crohn's disease. Conclusion We found several interesting clusters in monocytes before and after stimulation with lipopolysaccharide. These genes may have been responsible for the immunological differences between the Crohn's disease and control patients. [ABSTRACT FROM AUTHOR]

Background: It has been reported that inflammatory cell infiltration can be detected in patients with endoscopically negative gastroesophageal reflux disease (GERD) as well as those with erosive reflux esophagitis. In this study, we examined the expression of mRNA for interleukin (IL)-8, a potent chemokine for neutrophils, in the esophageal mucosa of patients with GERD and compared the results with their endoscopic findings and symptoms. Methods: Biopsy samples were obtained from 80 patients. Endoscopic diagnosis was performed according to the Los Angeles classification. Patients with typical symptoms such as heartburn despite normal endoscopic findings were classified as the non-erosive GERD group. Total cellular RNA was extracted from the biopsy samples and IL-8 mRNA was quantified by real-time polymerase chain reaction (PCR). Localization of IL-8 protein in the esophageal mucosa was done by immunostaining. Results: Expression of IL-8 mRNA was correlated with the endoscopic grade of esophagitis or with inflammatory cell infiltration, but not with the symptoms of the patients. Expression of IL-8 mRNA was also detected in all patients with non-erosive GERD. The level of IL-8 expression in non-erosive GERD was low compared with that in erosive GERD, but was higher than that in normal controls. IL-8 immunostaining was found in the basal layers of the esophageal mucosa. Administration of lansoprazole, a proton-pump inhibitor, decreased both IL-8 mRNA and protein levels in the esophageal mucosa. Conclusion: These results suggest that IL-8 in the esophageal mucosa may be involved in the pathogenesis of esophageal inflammation, including non-erosive GERD. [ABSTRACT FROM AUTHOR]

Summary Background : Recent studies have shown that Helicobacter pylori affects intracellular signal transduction in host cells, leading to the activation of transcriptional factors and the induction of pro-inflammatory cytokines. On the other hand, rebamipide, an anti-gastritis and anti-ulcer agent, could scavenge reactive oxygen species and reduce interleukin-8 (IL-8) expression in gastric epithelial cells induced by H. pylori -stimulation through the attenuated activation of nuclear factor-κB (NF-κB). Aims : In this study, we investigated the effects of rebamipide on gene expression in H. pylori -stimulated epithelial cells using DNA chip. Methods : H. pylori water extract (HPE) was prepared from NCTC11637, the type strain of H. pylori . Total RNA was extracted from MKN45 cells, a human gastric cancer cell line, following HPE-stimulation with and without rebamipide for 3 h, and differences in gene expression profiles were observed using GeneChip and Human 6800 probe array. Results : The GeneChip analysis demonstrated that 132 up-regulated genes and 873 down-regulated genes, such as growth factors, chemokines and transcription factors, were detected in MKN45 cells 3 h after stimulation of H. pylori . Among them, several genes, including bFGF, RANTES and MIP-2β, were previously unknown to be expressed in H. pylori -stimulated human gastric cells. Rebamipide reduced expression of 119 genes encoding cytokines, growth factors and their receptors and transcription factors. Conclusions : These findings suggest that rebamipide could inhibit inflammatory reactions and tumour progression by modifying H. pylori infection-induced gene expression in gastric epithelial cells. [ABSTRACT FROM AUTHOR]