The increased mucosal mRNA expressions of complement C3 and interleukin-17 in inflammatory bowel disease

Recent studies have demonstrated that the complement system participates in the regulation of T cell functions. To address the local biosynthesis of complement components in inflammatory bowel disease (IBD) mucosa, we investigated C3 and interleukin (IL)-17 mRNA expression in mucosal samples obtained from patients with IBD. The molecular mechanisms underlying C3 induction were investigated in human colonic subepithelial myofibroblasts (SEMFs). IL-17 and C3 mRNA expressions in the IBD mucosa were evaluated by real-time polymerase chain reaction. The C3 levels in the supernatant were determined by enzyme-linked immunosorbent assay. IL-17 and C3 mRNA expressions were elevated significantly in the active lesions from ulcerative colitis (UC) and Crohn's disease (CD) patients. There was a significant positive correlation between IL-17 and C3 mRNA expression in the IBD mucosa. IL-17 stimulated a dose- and time-dependent increase in C3 mRNA expression and C3 secretion in colonic SEMFs. The C3 molecules secreted by colonic SEMFs were a 115-kDa alpha-chain linked to a 70-kDa beta-chain by disulphide bonds, which was identical to serum C3. The IL-17-induced C3 mRNA expression was blocked by p42/44 mitogen-activated protein kinase (MAPK) inhibitors (PD98059 and U0216) and a p38 MAPK inhibitor (SB203580). Furthermore, IL-17-induced C3 mRNA expression was inhibited by an adenovirus containing a stable mutant form of I kappaB alpha. C3 and IL-17 mRNA expressions are enhanced, with a strong correlation, in the inflamed mucosa of IBD patients. Part of these clinical findings was considered to be mediated by the colonic SEMF response to IL-17.

Energy metabolism in Japanese patients with Crohn's disease

We investigated energy expenditure in hospitalized patients with Crohn’s disease (CD), and determined optimal energy requirements for nutritional therapy. Sixteen patients (5 women and 11 men, mean age 36 year old, mean BMI 18.7 kg/m²) and 8 healthy volunteers were enrolled in this study. Measured resting energy expenditure (mREE) levels were determined by indirect calorimetry. The mREEs in CD patients were significantly higher than those of healthy controls (24.4 ± 2.4 kcal/kg/day vs 21.3 ± 1.7 kcal/kg/day). However, mREEs in CD patients were significantly lower than predicted REEs (pREEs) calculated by the Harris-Benedict equation (26.4 ± 2.5 kcal/kg/day). Furthermore, mREE/pREE values were lower in undernourished patients than in well-nourished patients. CD patients had hyper-metabolic statuses evaluated by mREE/body weight, but increased energy expenditure did not contribute to weight loss in these patients. In conclusion, nutritional therapy with 25–30 kcal/ideal body weight/day (calculated by mREE × active factor) may be optimal for active CD patients, while higher energy intake values pose the risk of overfeeding.

Recent advances in molecular approaches to gut microbiota in inflammatory bowel disease

Inflammatory bowel diseases [IBD], ulcerative colitis [UC] and Crohn's disease [CD], are chronic intestinal disorders of unknown etiology. UC and CD are heterogeneous diseases characterized by various genetic abnormalities that lead to overly aggressive T-cell responses to a subset of commensal enteric bacteria in genetically susceptible individuals. As one of critical factors involved in pathogenesis of IBD, relative imbalance of aggressive and protective bacterial species, termed dysbiosis, has been reported by various literatures. Since early days of microbiology, representatives of microbial species [over 400 species] have been isolated from human gastrointestinal tract, and analyses of dysbiosis in IBD were mainly dependent on culture techniques. However, recent molecular ecological studies based on ribosomal RNA [rRNA] sequences have revealed that cultivation has been able only to access a small fraction of the microbial diversity within the gastrointestinal tract. These techniques enable characterization and quantification of the microbiota. Clone libraries enable identification of the composition of the microbiota. Microbial community structure can be analyzed via fingerprinting techniques, and dot blot hybridization or fluorescent in situ hybridization can analyze abundance of particular taxa. Recent report shows a systematic framework of the microbial diversity in the human gut of more than 1000 different species-level phylogenetic types [phylotypes]. This review focuses on recent advances in the molecular ecological approaches for studying the gut microbiota in IBD.

Expression of IL-24, an activator of the JAK1/STAT3/SOCS3 cascade, is enhanced in inflammatory bowel disease

IL-24 is a member of the IL-10 family of cytokines. In this study, we investigated IL-24 expression in the inflamed mucosa of patients with inflammatory bowel disease (IBD), and characterized the molecular mechanisms responsible for IL-24 expression in human colonic subepithelial myofibroblasts (SEMFs). IL-24 expression in the IBD mucosa was evaluated by immunohistochemical methods. IL-24 mRNA and protein expression was determined by real-time PCR and ELISA, respectively. AP-1 and C/EBP DNA-binding activity and IL-24 promoter activity were assessed by EMSA analysis and a reporter gene assay, respectively. IL-24 mRNA expression was significantly elevated in active lesions from patients who have ulcerative colitis and Crohn's disease. Colonic SEMFs were identified as a major source of IL-24 in the mucosa. IL-1beta, but not IL-17A, TNF-alpha, or IFN-gamma, significantly enhanced IL-24 mRNA and protein expression in isolated colonic SEMFs. The IL-1beta-induced IL-24 mRNA expression was mediated by the activation of the transcription factors, AP-1 and C/EBP-beta. Induction of IL-24 mRNA stabilization was also involved in the effects of IL-1beta. IL-24 induced JAK1/STAT-3 phosphorylation and SOCS3 expression in HT-29 colonic epithelial cells. IL-24 did not modulate the proliferation of HT-29 cells, but significantly increased the mRNA expression of membrane-bound mucins (MUC1, MUC3, and MUC4). IL-24 derived from colonic SEMFs acts on colonic epithelial cells to elicit JAK1/STAT-3 activation and the expression of SOCS3 and mucins, supporting their suppressive effects on mucosal inflammation in IBD.

Interleukin-32 expression in the pancreas

Interleukin (IL)-32 is a recently described proinflammatory cytokine characterized by the induction of nuclear factor (NF)-kappaB activation. We studied IL-32 expression in human pancreatic tissue and pancreatic cancer cell lines. Tissue samples were obtained surgically. IL-32 expression was evaluated by standard immunohistochemical procedures. IL-32 mRNA expression was analyzed by Northern blotting and real time PCR analyses. IL-32 was weakly immunoexpressed by pancreatic duct cells. In the inflamed lesions of chronic pancreas, the ductal expression of IL-32 was markedly increased. A strong expression of IL-32alpha was detected in the pancreatic cancer cells. In pancreatic cancer cell lines (PANC-1, MIA PaCa-2, and BxPC-3 cells), the expression of IL-32 mRNA and protein was enhanced by IL-1beta, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha. An inhibitor of phosphatidylinositol 3-kinase (LY294002) significantly suppressed the IL-1beta-, IFN-gamma- and TNF-alpha-induced IL-32 mRNA expression. The blockade of NF-kappaB and activated protein-1 activation markedly suppressed the IL-1beta-, IFN-gamma-, and/or TNF-alpha-induced IL-32 mRNA expression. Furthermore, IL-32-specific small interfering RNA significantly decreased the uptake of [3H]thymidine and increased the annexin V-positive population (apoptotic cells) in PANC-1 cells. IL-32 knockdown also suppressed the mRNA expression of antiapoptotic proteins (Bcl-2, Bcl-xL, and Mcl-1). Pancreatic duct cells are the local source of IL-32, and IL-32 may play an important role in inflammatory responses and pancreatic cancer growth.

Lack of macrophage migration inhibitory factor suppresses innate immune response in murine dextran sulfate sodium-induced colitis

OBJECTIVE

Macrophage migration inhibitory factor (MIF) plays an important role in the development of inflammatory diseases. Recent studies have indicated an association of MIF with gastrointestinal inflammation including colitis, but the mechanism by which MIF exacerbates gut inflammation has not been fully clarified. In this study, in order further to clarify the role of MIF in intestinal inflammation, we investigated the association of MIF with innate immunity in experimental colitis using MIF-deficient mice.

MATERIAL AND METHODS

Colitis was induced by treating mice with 3% dextran sulfate sodium (DSS) solution for 7 days. The expressions of chemokines in the colon were determined by reverse transcriptase-polymerase chain reaction (RT-PCR). Myeloperoxidase activity in the colon was measured and immunohistochemistry for F4/80 was analyzed.

RESULTS

DSS treatment increased the level of myeloperoxidase activity and infiltration of F4/80-stained cells in the colon, and up-regulated the mRNA expressions in macrophage inflammatory protein (MIP)-1alpha, MIP-2, macrophage chemotaxic protein (MCP)-1, and interferon inducible protein (IP)-10 in wild-type mice. In contrast, this increase and up-regulation were not observed in the colon of MIF-deficient mice treated with DSS.

CONCLUSION

Our findings indicate that a lack of MIF suppresses the innate immune response in DSS-induced colitis.

Usefulness of bispectral monitoring of conscious sedation during endoscopic mucosal dissection

AIM: To assess the usefulness of bispectral index (BIS) monitoring in order to carry out endoscopic submucosal dissection (ESD) safely and with patients’ satisfaction.

METHODS: Three hundred sixty-six patients with an early-stage neoplasm of the digestive tract were enrolled. The BIS monitor (A-1050: Aspect medical systems/NIHON KOHDEN, Tokyo, Japan) was used. The appropriate sedative condition was set at 55 to 75 BIS levels (BIS value) during the endoscopic procedures.

RESULTS: Among 366 cases, 13 were accompanied by adverse events during and/or after ESD. All episodes occurred in cases with BIS value between 56 and 65. Hypotension was observed in four cases, and bradycardia in six. Respiratory distress was observed in two cases with chronic pulmonary obstructive disease. All patients with adverse events were able to leave the hospital without extension of the hospitalization.

CONCLUSION: BIS monitoring is useful to safely perform ESD. A BIS value of 70 to 75 is suitable for ESD.

Alendronate improves low bone mineral density induced by steroid therapy in Crohn's disease

AIM

We investigated whether steroid therapy for Crohn's disease (CD) patients influences bone mineral density (BMD), and whether alendronate is effective for improving this loss of BMD.

METHODS

We recruited 16 outpatients with CD. The BMD of the whole body, the lumbar spine, and the proximal femoral neck was measured by dual-energy X-ray absorptimetry. The BMD was expressed as a T score. Some CD patients with low BMD values had been given vitamin K2 or alendronate for one year.

RESULTS

In the steroid-dependent group, the mean dose of prednisolone was 968 mg per year and 2.7 mg per day. Although the duration of the disease was not related to the T score, the amount of total steroids was negatively correlated with the T score among patients taking no preventative drugs. The T score in the vitamin K2 group after one year did was not altered in the 3 areas examined. On the other hand, the T score in the alendronate group increased by 2.8% for the whole body, 4.5% in the lumbar spine, and 3.4% in the proximal femoral neck.

CONCLUSION

The BMD of Japanese CD patients was decreased depending on the total amount of steroid administered, and oral alendronate improved the loss of BMD.

Faecal microbiota profile of Crohn's disease determined by terminal restriction fragment length polymorphism analysis

BACKGROUND

Terminal restriction fragment length polymorphism (T-RFLP) analyses are powerful tools to assess the diversity of complex microbiota. T-RFLPs permit rapid comparisons of microbiota from many samples.

AIM

To perform T-RFLP analyses of faecal microbiota in Crohn's disease (CD) patients to investigate potential alterations in faecal microbial communities and furthermore to analyse the effects of elemental diet on faecal microbiota profiles.

METHODS

Thirty-four patients with CD and 30 healthy individuals were enrolled in the study. DNA was extracted from stool samples and 16S rRNA genes were amplified by PCR. PCR products were digested with BslI restriction enzymes and T-RF lengths were determined.

RESULTS

Faecal microbial communities were classified into seven clusters. Almost all healthy individuals (28/30) were included in cluster I, II and III, but the majority of CD patients (25/34) could be divided into another four clusters (cluster IV-VII). Prediction of bacteria based on the BslI-digested T-RFLP database showed a significant decrease in Clostridium cluster IV, Clostridium cluster XI and subcluster XIVa in CD patients. In contrast, Bacteroides significantly increased in CD patients. Significant increases in Enterobacteriales were also observed in CD patients. Furthermore, elemental diets modulated faecal bacterial communities in CD patients.

CONCLUSIONS

Terminal restriction fragment length polymorphism analyses showed that the diversity of faecal microbiota in patients with CD differed from that of healthy individuals. Furthermore, elemental diets modulated faecal microbiota composition, and this effect may be involved in mechanisms of clinical effects of elemental diet.

Chemoradiation therapy followed by endoscopic submucosal dissection for esophageal cancer

We performed chemoradiation therapy (CRT) followed by an endoscopic submucosal dissection (ESD) for three patients with esophageal cancer. One patient refused surgery, and two patients were complicated with severe cardiopulmonary diseases. In all patients, CRT was effective in reducing tumor size, and the residual tumors were completely resected by ESD. All patients were recurrence-free for 6 months to 2.5 years. The combination of CRT plus subsequent ESD may be useful for treating patients with esophageal cancer who are not fit to undergo surgery.

Detection of N-nitroso-bile acids at 285 nm in reverse-phase HPLC

In the present study, we developed a novel, simple, and specific detection method using an RP-HPLC at UV 285 nm for the separation and quantification of N-nitroso-bile acids. First, we found that N-nitroso-bile acids have a specific spectrophotometric absorbance at 285 nm. Using this 285 nm detection system, we could especially measure N-nitroso-bile acids, even in co-existence of non-N-nitroso-bile acids. Next, we observed the decomposition of N-nitroso-glychocholate under alkaline, acidic, and neutral conditions. N-nitroso-glychocholate rapidly decomposed under alkaline conditions (pH 9) (t(1/2) = 0.96 h), but remained fairly stable under acidic (pH 2) (t(1/2) = 12.8 h) and neutral (pH 7) (t(1/2) = 7.8 h) conditions. This study is the first report, which simply and specifically analyzes N-nitroso-bile acids using an RP-HPLC system.

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-1β (IL-1β) and tumor necrosis factor-α (TNF-α) 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-1β and TNF-α expression, suggesting a role of p38 mitogen-activated protein kinase (MAPK)-mediated proinflammatory cytokine induction in host defense mechanisms.

Mucosal cytokine network in inflammatory bowel disease

Inflammatory bowel disease (IBD), ulcerative colitis (UC) and Crohn’s disease (CD) are characterized by ongoing mucosal inflammation in which dysfunction of the host immunologic response against dietary factors and commensal bacteria is involved. The chronic inflammatory process leads to disruption of the epithelial barrier, and the formation of epithelial ulceration. This permits easy access for the luminal microbiota and dietary antigens to cells resident in the lamina propria, and stimulates further pathological immune cell responses. Cytokines are essential mediators of the interactions between activated immune cells and non-immune cells, including epithelial and mesenchymal cells. The clinical efficacy of targeting TNF-α clearly indicates that cytokines are the therapeutic targets in IBD patients. In this manuscript, we focus on the biological activities of recently-reported cytokines [Interleukin (IL)-17 cytokine family, IL-31 and IL-32], which might play a role through interaction with TNF-α in the pathophysiology of IBD.

Lower-Dose and Long-Term Intermittent Interferon Therapy for Hepatitis C Genotype 2a may be a Possibility

We report two recent, successful cases in treating active chronic hepatitis C patients (genotype 2a) with a lower-dose and long-term intermittent interferon therapy. Case 1: A 67-year-old female received IFN-alpha 3 MU twice a week. Biochemical and virological remissions were achieved after 4 weeks and 14 months, respectively. We changed the IFN to pegylated-interferon alpha-2a (P-IFN) 45 μg once a week. After which, we successfully reduced the frequency of injections to once a month while maintaining both remissions. Case 2: A 61-year-old male had received a conventional genetical recombination interferon therapy. However, the hepatitis recurred. He was given IFN-alpha 3 MU once a week. A biochemical remission was achieved after 3 months. After 7 months, we changed the IFN to P-IFN 90 μg once a week, and a virological remission soon occurred. Then, we also could reduce the frequency to once every two months. Our novel strategy using P-IFN is safe and economic.

Monitoring 6-thioguanine nucleotide concentrations in Japanese patients with inflammatory bowel disease

BACKGROUND AND AIM

There have been no reports on 6-thioguanine nucleotide (6-TGN) concentrations in Japanese patients with inflammatory bowel disease (IBD) undergoing azathioprine (AZA) or 6-mercaptopurine (6-MP) therapy. The aim of this study was to assess 6-TGN concentrations in Japanese IBD patients.

METHODS

Eighty-three patients with Crohn's disease (n = 42) and ulcerative colitis (n = 41) were enrolled. In 69 patients, AZA was prescribed at 50 mg/day, and seven patients were given 75 (n = 5) or 100 mg/day (n = 2). 6-MP was administered at 30 mg/day (n = 7). The 6-TGN concentrations were then assayed by high-performance liquid chromatography.

RESULTS

The mean 6-TGN concentrations of the entire study population (n = 83) were 277.9 +/- 179.8 pmol/8 x 10(8) red blood cells (RBC). The mean 6-TGN concentrations in those patients with active disease (n = 38) and those in remission (n = 45) were 232.9 +/- 159.7(mean +/- SD) and 342.8 +/- 184.6 pmol/8 x 10(8) RBC, respectively (P < 0.05). The odds ratio of being in remission and having a 6-TGN value >235 pmol/8 x 10(8) RBC was 2.6 (95% CI 1.05-6.2). A significant inverse correlation was found between the white blood cell (WBC) counts and 6-TGN concentrations (r = -0.301, P < 0.05, n = 83); the mean WBC counts of the active patients (6780 +/- 2412) were significantly higher than the patients in clinical remission (5468 +/- 1920, P < 0.05). Three patients with severe leukopenia and 10 patients with high 6-TGN concentrations had no thiopurine S-methyl transferase mutations.

CONCLUSION

The 6-TGN concentrations in Japanese patients with IBD on low-dose AZA and 6-MP therapy were comparable to those reported from Western countries. The monitoring of 6-TGN concentrations may be helpful for developing a therapeutic strategy for Japanese IBD patients.

[Case report: periodical infliximab administration enabled closure of colostomy in fistulating perianal Crohn's disease]

A 29-year old woman with Crohn's disease was performed colostomy due to severe perianal abscess. Her disease had been easy to recur and she was admitted to hospital for intestinal bleeding caused by acute exacerbation in Crohn's disease on October 2006. The bleeding was stopped rapidly and clinical remission was maintained with bimonthly administration of infliximab. Finally, her colostomy was closed after 5 years 8 months. Periodical treatment of infliximab not only prevented recurrence but also enabled closure of colostomy in fistulating perianal Crohn's disease.

Phosphatidylinositol 3-kinase/Akt signaling mediates interleukin-32alpha induction in human pancreatic periacinar myofibroblasts

Interleukin (IL)-32 is a recently described proinflammatory cytokine, characterized by the induction of nuclear factor (NF)-kappaB activation. We studied IL-32alpha expression in human pancreatic periacinar myofibroblasts, which play important roles in the regulation of extracellular matrix metabolism and inflammatory responses in the pancreas. IL-32alpha protein expression was evaluated by Western blot analyses, and IL-32alpha mRNA expression was analyzed by Northern blot and real-time PCR analyses. IL-32alpha mRNA was weakly expressed without a stimulus, and its expression was markedly enhanced by IL-1beta, IFN-gamma, and TNF-alpha. IL-1beta, IFN-gamma, and TNF-alpha enhanced intracellular accumulation of IL-32alpha protein, but IL-32alpha was not detected in supernatants. Each cytokine dose and time dependently induced IL-32alpha mRNA expression. An inhibitor of phosphatidylinositol 3-kinase (LY294002) significantly suppressed IL-1beta-, IFN-gamma-, and TNF-alpha-induced IL-32alpha mRNA expression, although MAPK inhibitors had no effect. Akt activation in response to these cytokines was confirmed by Western blot. Furthermore, LY294002 suppressed both IL-1beta- and TNF-alpha-induced NF-kappaB activation and IL-1beta-, TNF-alpha-, and IFN-gamma-induced activated protein-1 (AP-1) activation. Blockade of NF-kappaB and AP-1 activation by an adenovirus expressing a stable mutant form of IkappaBalpha and a dominant negative mutant of c-Jun markedly suppressed IL-1beta-, IFN-gamma-, and/or TNF-alpha-induced IL-32alpha mRNA expression. Human pancreatic periacinar myofibroblasts expressed IL-32alpha in response to IL-1beta, TNF-alpha, and IFN-gamma. IL-32alpha mRNA expression is dependent on interactions between the phosphatidylinositol 3-kinase/Akt-pathway and the NF-kappaB/AP-1 system.