Phlebosclerotic colitis that was difficult to distinguish from collagenous colitis

Phlebosclerotic colitis is a rare and recently known disease entity and its etiology is still to be elucidated. Some phlebosclerotic colitis cases are difficult to distinguish from collagenous colitis because of the similarity of pathological findings. In all Japanese case reports of phlebosclerotic colitis in which an association with the use of Chinese herbal medicine is suspected, sansisi (gardenia fruit) was included, suggesting pathogenesis of this disease. We report a case of phlebosclerotic colitis that wasdifficult to be distinguished from collagenous colitis, and an association with the use of Chinese herbal medicine was suspected as the cause of the disease.

Randomized clinical trial: rikkunshito in the treatment of functional dyspepsia--a multicenter, double-blind, randomized, placebo-controlled study

BACKGROUND

Rikkunshito, a standardized Japanese herbal medicine, is thought to accelerate gastric emptying and relieve dyspepsia, although no large-scale, randomized, placebo-controlled trials of rikkunshito have been conducted. This study aimed to determine the efficacy and safety of rikkunshito for treating functional dyspepsia (FD).

METHODS

FD patients received 2.5 g rikkunshito or placebo three times a day for 8 weeks in this multicenter, randomized, placebo-controlled, parallel-group trial. The primary end point was the proportion of responders at 8 weeks after starting test drug, determined by global patient assessment (GPA). The improvement in four major dyspepsia symptoms severity scale was also evaluated. In addition, plasma ghrelin levels were investigated before and after treatment.

KEY RESULTS

Two hundred forty-seven patients were randomly assigned. In the eighth week, the rikkunshito group had more GPA responders (33.6%) than the placebo (23.8%), although this did not reach statistical significance (p = 0.09). Epigastric pain was significantly improved (p = 0.04) and postprandial fullness tended to improve (p = 0.06) in the rikkunshito group at week 8. Rikkunshito was relatively more effective among Helicobacter pylori-infected participants (rikkunshito: 40.0% vs placebo: 20.5%, p = 0.07), and seemed less effective among H. pylori-uninfected participants (rikkunshito: 29.3% vs placebo: 25.6%, p = 0.72). Among H. pylori-positive individuals, acyl ghrelin levels were improved just in rikkunshito group. There were no severe adverse events in both groups.

CONCLUSIONS & INFERENCES

Administration of rikkunshito for 8 weeks reduced dyspepsia, particularly symptoms of epigastric pain and postprandial fullness. (UMIN Clinical Trials Registry, Number UMIN000003954).

Development and testing of an endoscopic pseudo-viewpoint alternating system

Purpose

   An endoscopic system is needed that presents informative images irrespective of the surgical situation and the number of degrees of freedom in endoscopic manipulation. This goal may be achieved with a virtual reality view for a region of interest from an arbitrary viewpoint. An endoscopic pseudo-viewpoint alternation system for this purpose was developed and tested.

Method

   Surgical experts and trainees from an endoscopic surgery training course at the minimally invasive surgery training center of Kyushu University were enrolled in a trial of a virtual reality system. The initial viewpoint was positioned to approximate the horizontal view often seen in laparoscopic surgery, with \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$20^{\circ }$$\end{document}20∘ between the optical axis of the endoscope and the task surface. A right-to-left suturing task with right hand, based on a task from the endoscopic surgery training course, was selected for testing. We compared task outcomes with and without use of a new virtual reality-viewing system.

Result

   There was a 0.37 mm reduction in total error (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p = 0.02$$\end{document}p=0.02) with use of the proposed system. Error reduction was composed of 0.1 mm reduction on the y-axis and 0.27 mm reduction on the x-axis. Experts benefited more than novices from use of the proposed system. Most subjects worked at a pseudo-viewpoint of around 34\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^\circ $$\end{document}∘.

Discussion

   Suturing performance improved with the new virtual reality endoscopic display system. Viewpoint alternation resulted in an overview that improved depth perception and allowed subjects to better aim the marker. This suggests the proposed method offers users better visualization and control in endoscopic surgery.

Design and fabrication of a perpendicular magnetic tunnel junction based nonvolatile programmable switch achieving 40% less area using shared-control transistor structure

A compact nonvolatile programmable switch (NVPS) using 90 nm CMOS technology together with perpendicular magnetic tunnel junction (p-MTJ) devices is fabricated for zero-standby-power field-programmable gate array. Because routing information does not change once it is programmed into an NVPS, high-speed read and write accesses are not required and a write-control transistor can be shared among all the NVPSs, which greatly simplifies structure of the NVPS. In fact, the effective area of the proposed NVPS is reduced by 40% compared to that of a conventional MTJ-based NVPS. The instant on/off behavior without external nonvolatile memory access is also demonstrated using the fabricated test chip.

Trans fatty acids exacerbate dextran sodium sulphate-induced colitis by promoting the up-regulation of macrophage-derived proinflammatory cytokines involved in T helper 17 cell polarization

Numerous reports have shown that a diet containing large amounts of trans fatty acids (TFAs) is a major risk factor for metabolic disorders. Although recent studies have shown that TFAs promote intestinal inflammation, the underlying mechanisms are unknown. In this study, we examined the effects of dietary fat containing TFAs on dextran sodium sulphate (DSS)-induced colitis. C57 BL/6 mice were fed a diet containing 1·3% TFAs (mainly C16:1, C18:1, C18:2, C20:1, C20:2 and C22:1), and then colitis was induced with 1·5% DSS. Colonic damage was assessed, and the mRNA levels of proinflammatory cytokines and major regulators of T cell differentiation were measured. The TFA diet reduced survival and exacerbated histological damage in mice administered DSS compared with those fed a TFA-free diet. The TFA diet significantly elevated interleukin (IL)-6, IL-12p40, IL-23p19 and retinoic acid-related orphan receptor (ROR)γt mRNA levels in the colons of DSS-treated animals. Moreover, IL-17A mRNA levels were elevated significantly by the TFA diet, with or without DSS treatment. We also examined the expression of proinflammatory cytokines in lipopolysaccharide (LPS)-stimulated RAW264.7 cells and peritoneal macrophages. These cells were exposed to TFAs (linoelaidic acid or elaidic acid) with or without LPS and the mRNA levels of various cytokines were measured. IL-23p19 mRNA levels were increased significantly by TFAs in the absence of LPS. Cytokine expression was also higher in LPS-stimulated cells exposed to TFAs than in unexposed LPS-stimulated cells. Collectively, our results suggest that TFAs exacerbate colonic inflammation by promoting Th17 polarization and by up-regulating the expression of proinflammatory cytokines in the inflamed colonic mucosa.

Free cholesterol accumulation in hepatic stellate cells: mechanism of liver fibrosis aggravation in nonalcoholic steatohepatitis in mice

Although nonalcoholic steatohepatitis (NASH) is associated with hypercholesterolemia, the underlying mechanisms of this association have not been clarified. We aimed to elucidate the precise role of cholesterol in the pathophysiology of NASH. C57BL/6 mice were fed a control, high-cholesterol (HC), methionine-choline-deficient (MCD), or MCD+HC diet for 12 weeks or a control, HC, high-fat (HF), or HF+HC diet for 24 weeks. Increased cholesterol intake accelerated liver fibrosis in both the mouse models without affecting the degree of hepatocellular injury or Kupffer cell activation. The major causes of the accelerated liver fibrosis involved free cholesterol (FC) accumulation in hepatic stellate cells (HSCs), which increased Toll-like receptor 4 protein (TLR4) levels through suppression of the endosomal-lysosomal degradation pathway of TLR4, and thereby sensitized the cells to transforming growth factor (TGF)β-induced activation by down-regulating the expression of bone morphogenetic protein and activin membrane-bound inhibitor. Mammalian-cell cholesterol levels are regulated by way of a feedback mechanism mediated by sterol regulatory element-binding protein 2 (SREBP2), maintaining cellular cholesterol homeostasis. Nevertheless, HSCs were sensitive to FC accumulation because the high intracellular expression ratio of SREBP cleavage-activating protein (Scap) to insulin-induced gene (Insig) disrupted the SREBP2-mediated feedback regulation of cholesterol homeostasis in these cells. HSC activation subsequently enhanced the disruption of the feedback system by Insig-1 down-regulation. In addition, the suppression of peroxisome proliferator-activated receptor γ signaling accompanying HSC activation enhanced both SREBP2 and microRNA-33a signaling. Consequently, FC accumulation in HSCs increased and further sensitized these cells to TGFβ-induced activation in a vicious cycle, leading to exaggerated liver fibrosis in NASH.

CONCLUSION

These characteristic mechanisms of FC accumulation in HSCs are potential targets to treat liver fibrosis in liver diseases including NASH.

Trans fatty acids in diets act as a precipitating factor for gut inflammation?

Fatty acids in our daily diet are broadly classified into cis and trans fatty acids (TFAs). TFAs are formed during the manufacturing process of hydrogenated vegetable oils such as margarine. Modern diets such as deep-fried products, frozen foods, and packaged snacks commonly include large quantities of margarine containing TFAs. Although an increased report in the effects of the diet containing TFAs on a risk factor of metabolic syndrome, diabetes mellitus, and coronary heart disease has been observed in the recent years, influence on intestinal inflammation remains unknown. This review describes pro-inflammatory effects of TFAs in our diary diet on various systemic disorders and also discusses a possible role of TFAs on gut inflammation.

Effect of dietary fat on intestinal inflammatory diseases

Dietary fat has multiple roles on human health, and some dietary fat is used to treat organic diseases because of its anti-inflammatory effect. It is commonly accepted that omega-3 polyunsaturated fatty acid (PUFA) is beneficial on ischemic heart disease or rheumatic arthritis. On the contrary, effect of omega-3-PUFA on Crohn's disease remained controversial. That effect of omega-3 PUFA differs according to the location of inflamed intestine was hypothesized. To elucidate this hypothesis, to investigate the role of dietary fat on disease activity in different kind of murine models of intestinal inflammatory diseases was planned. The effect of omega-3 PUFA on small intestinal Crohn's disease model and large intestinal Crohn's disease model of mice. Chronic colitis model C57BL/6 mice received two cycles of dextran sodium sulfate solution treatment to induce chronic colitis. Feeding of omega-3 fat-rich diets exacerbated colitis with decrease in adiponectin expression. Chronic small intestinal inflammation model: SAMP1/Yit mice showed remarkable inflammation of the terminal ileum spontaneously. Feeding of omega-3 fat-rich diets for 16 weeks significantly ameliorated the inflammation of the terminal ileum. Enhanced infiltration of leukocytes and expression of mucosal addressin cell adhesion molecule-1 in intestinal mucosa was significantly decreased by omega-3 fat-rich diets treatment. Omega-3 PUFA has dual role, pro-/anti-inflammatory, on intestinal inflammatory diseases. The role of omega-3 fat and the potential for immunonutrition in inflammatory conditions of the gastrointestinal tract will be discussed.

Endoscopic finding of spontaneous hemorrhage correlates with tumor necrosis factor alpha expression in colonic mucosa of patients with ulcerative colitis

BACKGROUND

Ulcerative colitis (UC) is an intractable colonic disease, and it shows several endoscopic findings. Recently, it was reported that the expression level of mucosal tumor necrosis factor alpha (TNF-α) was useful for predicting patient response to infliximab. However, no data regarding the value of endoscopic findings to predict treatment efficacy or cytokine expression level exist.

OBJECTIVE

We investigated the expression of leukocyte adhesion-related molecules and cytokines in colonic mucosa and compared it to endoscopic findings.

METHODS

One hundred and fifty-nine patients were enrolled. Tissue samples were obtained by colonic biopsy from patients with UC. Colitis activity was determined by Matts' criteria. The degree of mRNA expression of TNF-α, interferon gamma (IFN-γ), interleukin (IL)-8, IL-17A, and mucosal vascular addressin adhesion molecule-1 (MAdCAM-1) in mucosal samples was determined by real-time quantitative polymerase chain reaction. These expression levels were compared with the degree of Matts' grade and individual endoscopic findings.

RESULTS

The expression of TNF-α, IFN-γ, IL-8, IL-17A, and MAdCAM-1 mRNA significantly increased as Matts' endoscopic grade elevated. Actively inflamed mucosa with spontaneous hemorrhage revealed a significantly increased expression level of TNF-α mRNA than that without spontaneous hemorrhage. No other individual endoscopic parameter was significantly correlated with the expression level of TNF-α mRNA.

CONCLUSIONS

Inflamed mucosa with spontaneous hemorrhage may suggest increased expression of TNF-α mRNA levels in colonic mucosa of UC patients, which could predict a lower response to infliximab treatment and more aggressive induction regime or change to other therapy should be taken into account.

Norovirus binding to intestinal epithelial cells is independent of histo-blood group antigens

Human noroviruses (NoVs) are a major cause of non-bacterial gastroenteritis. Although histo-blood group antigens (HBGAs) have been implicated in the initial binding of NoV, the mechanism of that binding before internalization is not clear. To determine the involvement of NoVs and HBGAs in cell binding, we examined the localization of NoV virus-like particles (VLPs) and HBGAs in a human intestinal cell line and the human ileum biopsy specimens by immunofluorescence microscopy. The localizations of Ueno 7k VLPs (genogroup II.6) and each HBGA (type H1-, H2- and Le(b)-HBGAs) on the human intestinal cell line, Caco-2, were examined by confocal laser-scanning microscopy. To explore any interactions of NoVs and HBGAs in vivo, fresh biopsy specimens from human ileum were directly incubated with NoV VLPs and examined by immunofluorescence microscopy. We found that VLP binding depended on the state of cell differentiation, but not on the presence of HBGAs. In differentiated Caco-2 cells, we detected no type H1 HBGAs, but VLPs bound to the cells anyway. We incubated fresh biopsies of human ileum directly with VLPs, a model that better replicates the in vivo environment. VLPs mainly bound epithelial cells and goblet cells. Although the incubations were performed at 4°C to hinder internalization, VLPs were still detected inside cells. Our results suggest that VLPs utilize molecule(s) other than HBGAs during binding and internalization into cells.

Protective effects of Rho kinase inhibitor fasudil on rats with chronic kidney disease

The protective effects of Rho kinase inhibitor fasudil against renal diseases have recently been reported. We compared the therapeutic effects of fasudil on the spontaneously hypercholesterolemic (SHC) rat, a model of chronic kidney disease (CKD) with proteinuria, with those of the angiotensin receptor blocker olmesartan (OL) by paying attention to the proteinuria and the macrophage phenotype. SHC rats were allocated to six treatment groups: a vehicle (Ve) group, a low-dose fasudil (FL) group, a high-dose fasudil (FH) group, an OL group, a combination of low-dose fasudil and OL (CL) group, and a combination of high-dose fasudil and OL (CH) group. Sprague-Dawley rats treated with vehicle served as a control ( n = 7/each). The rats were treated for 24 wk. Compared with the Ve group, proteinuria was significantly decreased in the FH, OL, and CL groups, and it completely disappeared in the CH group. Glomerular stainings of nephrin and F-actin were focally impaired in the Ve group but were restored in the CH group. Western blotting showed that the CH group had significantly increased renal nephrin expression compared with the Ve group. Interstitial infiltration of macrophages was significantly increased in the Ve group, which was significantly attenuated in all treatment groups. The ratio of CD206 (M2 macrophage marker) to CD68 mRNA was significantly greater in the CH group than in the Ve group. These results indicate that fasudil with OL reduces proteinuria by protecting podocyte integrity and alters the interstitial macrophage density/phenotype, thereby exerting renoprotective effects against CKD.

Involvement of autotaxin/lysophospholipase D expression in intestinal vessels in aggravation of intestinal damage through lymphocyte migration

Lysophosphatidic acid (LPA) has a critical role in lymphocyte migration to secondary lymphoid organs. Autotaxin (ATX)/lysophospholipase D, in the vascular endothelium, is the main enzyme involved in LPA production. Whether ATX is involved in pathological lymphocyte migration to the inflamed mucosa has not been studied. We investigated the involvement of ATX in inflammatory bowel disease patients and two murine models of colitis. Tissue samples were obtained by intestinal biopsies from patients with Crohn's disease and those with ulcerative colitis with informed consent. ATX immunoreactivity was colocalized with MAdCAM-1-positive high-endothelial-like vessels, close to sites of lymphocyte infiltration. Enhanced expression of ATX mRNA was observed in the inflamed mucosa from Crohn's disease and ulcerative colitis patients. ATX mRNA expression level was remarkably higher in the actively inflamed mucosa than in the quiescent mucosa in the same patient. In the T-cell-transferred mouse model, ATX mRNA expression level gradually increased as colitis developed. In the dextran sodium sulfate mouse model, the expression level was considerably higher in colonic mucosa of chronically developed colitis than in colonic mucosa of acute colitis. Administration of an ATX inhibitor, bithionol, remarkably decreased lymphocyte migration to the intestine and ameliorated both dextran sodium sulfate-induced colitis and CD4-induced ileocolitis. In transwell assays, administration of bithionol or 1-bromo-3(s)-hydroxy-4-(palmitoyloxy) butylphosphonate (BrP-LPA) significantly decreased transmigration of splenocytes through high-endothelial-like vessels induced by TNF-α. We conclude that enhanced expression of ATX in the active mucosa has been implicated in the pathophysiology of inflammatory bowel disease through enhancing aberrant lymphocyte migration to the inflamed mucosa.

Dietary lipids and sweeteners regulate glucagon-like peptide-2 secretion

Glucagon-like peptide-2 (GLP-2) is a potent intestinal growth factor derived from enteroendocrine L cells. Although food intake is known to increase GLP-2 secretion, its regulatory mechanisms are largely unknown as a result of its very short half-life in venules. The aims of this study were to compare the effects of luminal nutrients on the stimulation of GLP-2 secretion in vivo using lymph samples and to clarify the involvement of the sweet taste receptor in this process in vitro. Lymph samples were collected from the thoracic duct after bolus administration of dietary lipids or sweetening agents into the duodenum of rats. Human enteroendocrine NCI-H716 cells were also used to compare the effects of various nutrients on GLP-2 secretion. GLP-2 concentrations were measured by ELISA in vivo and in vitro. GLP-2 secretion was enhanced by polyunsaturated fatty acid- and monounsaturated fatty acid-rich dietary oils, dietary carbohydrates, and some kinds of sweeteners in rats; this effect was reproduced in NCI-H716 cells using α-linolenic acid (αLA), glucose, and sweeteners. GLP-2 secretion induced by sweetening agents was inhibited by lactisole, a sweetness-antagonizing inhibitor of T1R3. In contrast, lactisole was unable to inhibit GLP-2 secretion induced by αLA alone. Our results suggested that fatty acid- and sweetener-induced GLP-2 secretion may be mediated by two different pathways, with the sweet taste receptor involved in the regulation of the latter.

Mucosal immunity in gut and lymphoid cell trafficking

Intestine has a well-developed lymphatic system that is closely related with its functions, such as mucosal immunological defense or absorption of nutrients. Intestinal lymphoid cells such as lymphocytes, macrophages/monocytes, or dendritic cells are continuously migrating through intestinal mucosa, thereby facilitating their immune responses. Their migrations are well controlled by well-organized molecular mechanisms including adhesion molecules, chemokines, etc. This manuscript will review how dysfunction of lymphoid cell migration is involved in intestinal inflammation, especially in the pathophysiology of intestinal bowel diseases. (*English Translation of J Jpn Coll Angiol 2008; 48: 143-149.).

Attenuation of acetic acid-induced gastric ulcer formation in rats by glucosylceramide synthase inhibitors

INTRODUCTION

Ceramide has been suggested to play a role in apoptosis during gastric ulcerogenesis. The present study is designed to investigate whether accumulated ceramide could serve as the effector molecules of ulcer formation in a rat model of acetic acid-induced gastric ulcer.

METHODS

The effect of fumonisin B1, an inhibitor of ceramide synthase, and of d,l,-threo-1-phenyl-2-hexadecanoylamino-3-morpholino-1-propanol (PPMP) and N-butyldeoxynojirimycin (NB-DNJ), both inhibitors of glucosylceramide synthase, on the accumulation of ceramide and formation of gastric ulcer were examined in the rat model of acetic acid-induced gastric ulcer.

RESULTS

Fumonisin B1 attenuated acetic acid-induced gastric ulcer formation, associated with a decrease in the number of apoptotic cells. Our results showed that it is neither the C18- nor the C24-ceramide itself, but the respective metabolites that were ulcerogenic, because PPMP and NB-DNJ attenuated gastric mucosal apoptosis and the consequent mucosal damage in spite of their reducing the degradation of ceramide.

CONCLUSION

The ceramide pathway, in particular, the metabolites of ceramide, significantly contributes to acetic acid-induced gastric damage, possibly via enhancing apoptosis. On the other hand, PPMP and NB-DNJ treatment attenuated gastric mucosal apoptosis and ulcer formation despite increasing the ceramide accumulation, suggesting that it was not the ceramides themselves, but their metabolites that contributed to the ulcer formation in the acetic acid-induced gastric ulcer model.