Chenodeoxycholic Acid Releases Proinflammatory Cytokines from Small Intestinal Epithelial Cells Through the Farnesoid X Receptor.

BACKGROUND/AIMS: Bile acids have recently been associated with the pathogenesis of irritable bowel syndrome (IBS). We therefore evaluated the expression of bile acid receptors in the intestinal mucosa of IBS patients as well as the effects of bile acids on small intestinal epithelial cells. METHODS: Intestinal biopsy specimens were obtained from 15 IBS patients and 15 healthy controls. The effects of bile acid stimulation on trans-epithelial electrical resistance (TEER) and permeability in differentiated Caco-2 cells were measured. Proinflammatory cytokines were measured by enzyme-linked immunosorbent assay. mRNA levels of bile acid receptors, including farnesoid X receptor (FXR), and cytokines were determined by real-time reverse transcription-PCR. Caco-2 cells were pre-incubated with the FXR antagonist guggulsterone. RESULTS: FXR mRNA expression at the terminal ileum was increased in IBS patients. Chenodeoxycholic acid (CDCA) significantly decreased TEER, increased permeability, and increased interleukin-8 (IL-8) release from Caco-2 cells. Pre-incubation with guggulsterone blocked CDCA-mediated IL-8 release; however, the decrease in TEER was not reversed. CDCA-induced IL-6 and IL-8 mRNA levels were blocked by guggulsterone. CDCA increased IL-6, tumor necrosis factor-α (TNF-α), and vascular endothelial growth factor release, whereas guggulsterone significantly blocked IL-6 and TNF-α release. CONCLUSIONS: FXR expression was elevated at the terminal ileum in IBS patients. CDCA increased proinflammatory cytokines, while guggulsterone blocked these increases.

The Link between Type III Reg and STAT3-Associated Cytokines in Inflamed Colonic Tissues.

Reg (regenerating gene) family proteins are known to be overexpressed in gastrointestinal (GI) tissues under conditions of inflammation. However, the pathophysiological significance of Reg family protein overexpression and its regulation is still unclear. In the present study, we investigated the profile of Reg family gene expression in a colitis model and focused on the regulation of Reg IIIß and IIIγ, which are overexpressed in inflamed colonic mucosa. C57BL/6 mice were administered 2% dextran sulfate sodium (DSS) in drinking water for five days, and their colonic tissues were investigated histopathologically at interval for up to 12 weeks. Gene expression of the Reg family and cytokines (IL-6, IL-17, and IL-22) was evaluated by real-time RT-PCR, and Reg IIIß/γ expression was examined by immunohistochemistry. The effects of cytokines on STAT3 phosphorylation and HIP/PAP (type III REG) expression in Caco2 and HCT116 cells were examined by Western blot analysis. Among Reg family genes, Reg IIIß and IIIγ were alternatively overexpressed in the colonic tissues of mice with DSS-induced colitis. The expression of STAT3-associated cytokines (IL-6, IL-17, and IL-22) was also significantly increased in those tissues, being significantly correlated with that of Reg IIIß/γ. STAT3 phosphorylation and HIP/PAP expression were significantly enhanced in Caco2 cells upon stimulation with IL-6, IL-17, and IL-22. In HCT116 cells, those enhancements were also observed by IL-6 and IL-22 stimulations but not IL-17. The link between type III Reg and STAT3-associated cytokines appears to play a pivotal role in the pathophysiology of DSS-induced colitis.

Filaggrin and tight junction proteins are crucial for IL-13-mediated esophageal barrier dysfunction.

Eosinophilic esophagitis (EoE) is an allergy-mediated disease that is accompanied by IL-13 overexpression and an impaired esophageal barrier. Filaggrin (FLG) and tight junction (TJ) proteins are considered to contribute to epithelial barrier function. However, their functional involvement in EoE has not been elucidated. Here, we aimed to determine the IL-13-mediated barrier dysfunction and expression of TJ-related proteins in EoE and to characterize interactions among TJ-related proteins involved in the barrier function of the esophageal epithelium. Biopsy specimens from EoE patients were analyzed. Primary human esophageal epithelial cells (HEECs) were cultured using an air-liquid interface (ALI) system. The permeability of TJs was assayed by biotinylation. Transepithelial electrical resistance (TEER) was measured after stimulation with IL-13 and after siRNA silencing of FLG expression. FLG and TJ genes and proteins were assessed by quantitative RT-PCR, Western blot analysis, and immunofluorescent staining. The biotinylation reagent diffused through the paracellular spaces of whole stratified epithelial layers in EoE biopsy samples. The TEER decreased in ALI-cultured HEECs after IL-13 stimulation. Although the protein level of FLG decreased, that of the TJ proteins increased in the mucosa of EoE biopsy samples and in ALI-cultured HEECs after IL-13 stimulation. IL-13 altered the staining patterns of TJ proteins and the epithelial morphology. FLG siRNA transfection significantly decreased TEER. The IL-13-mediated reduced esophageal barrier is associated with the altered expression pattern but not with the levels of TJ-associated proteins. A deficiency of FLG altered the stratified epithelial barrier. NEW & NOTEWORTHY Esophageal permeability to small molecules was increased in patients with eosinophilic esophagitis (EoE) and could be induced by IL-13 in our unique air-liquid interface-cultured primary multilayer human esophageal epithelial cells in vitro. A deficiency of filaggrin disrupted the esophageal stratified epithelial barrier. The decreased esophageal barrier in EoE was associated with the altered staining pattern of tight junction proteins, although the levels of the proteins themselves do not appear to be changed.

Systematic review with meta-analysis: Vonoprazan, a potent acid blocker, is superior to proton-pump inhibitors for eradication of clarithromycin-resistant strains of Helicobacter pylori.

BACKGROUND: Vonoprazan is a novel gastric acid suppressant that is applied in Japan to treat gastric diseases including Helicobacter pylori (H. pylori) infection. This meta-analysis aimed to summarize the ability of vonoprazan to eradicate clarithromycin-susceptible and clarithromycin-resistant H. pylori strains. MATERIALS AND METHODS: A systematic search was performed using PubMed, EMBASE, Web of Science, and Cochrane Library. Studies were included if they evaluated eradication rates of vonoprazan-based and conventional PPI-based triple therapies and checked for clarithromycin susceptibility of H. pylori. RESULTS: We identified 5 studies including a total of 1599 patients containing data regarding H. pylori with clarithromycin susceptibility. Among those infected with clarithromycin-susceptible H. pylori, eradication rates for vonoprazan-based and conventional PPI-based therapies did not significantly differ in either the randomized (RCT; pooled eradication rates, 95.4% vs 92.8%; pooled odds ratio [OR], 1.63; 95% confidence intervals [CI], 0.74-3.61; P = .225) and nonrandomized (NRCT; pooled eradication rates, 92.9% vs 86.2%; OR, 4.58; 95% CI, 0.67-31.45; P = .122) controlled trials. However, vonoprazan-based triple therapy was significantly superiority to PPI-based therapy for patients with clarithromycin-resistant strains in both RCT (pooled eradication rates, 82.0% vs 40.0%; OR, 6.83; 95% CI, 3.63-12.86; P < .0001) and NRCT (pooled eradication rates, 80.8% vs 41.8%; OR, 4.98; 95% CI, 2.47-10.03; P < .0001). CONCLUSIONS: Vonoprazan-based and conventional PPI-based therapies are similarly effective for the eradication of clarithromycin-susceptible H. pylori strains. Vonoprazan is superior to conventional PPI-based therapy for the eradication of clarithromycin-resistant H. pylori strains. However, clarithromycin was misused because the combination of vonoprazan and amoxicillin cures approximately 80% of infections without clarithromycin.

Sex differences in associations among metabolic syndrome, obesity, related biomarkers, and colorectal adenomatous polyp risk in a Japanese population.

To investigate sex differences in the associations among metabolic syndrome, obesity, adipose tissue-related biomarkers, and colorectal adenomatous polyps, a cross-sectional, multicenter study was conducted on 489 consecutive individuals who underwent their first colonoscopy at 3 hospitals. Plasma concentrations of adiponectin and leptin, as well as homeostatic model assessment of insulin resistance were also evaluated. The presence and number of adenomatous polyps, including advanced adenoma, were higher in men than in women. Metabolic syndrome was a risk factor for adenomatous polyps in both sexes. Large waist circumference was an independent risk factor for adenomatous polyps in men, and high BMI and large waist circumference were risk factors for adenomatous polyps in women. Interestingly, low BMI was associated with large adenomatous polyps (≥10 mm) and advanced adenoma, and waist-hip ratio was involved in proximal adenomatous polyp development only in women. In contrast, the highest quartile of leptin concentration had a 3.67-fold increased adenomatous polyp risk compared with the lowest quartile only in men. These results indicate that regarding colorectal pathogenesis, sex differences were identified in obesity but not in metabolic syndrome. Visceral obesity and a high serum leptin level may be risk factors for colorectal adenomatous polyp development in Japanese men.

[Diagnosis of duplication of the sigmoid colon prior to surgery:a case study].

A 16-year-old woman identified with colonic distention using chest X-rays visited our hospital. Although abdominal computed tomography (CT), colonoscopy, and barium enema study indicated suspected duplication of the sigmoid colon, the exact portion of communication between the normal colon and the duplicated colon could not be determined. The patient was released, but followed up due to the lack of symptoms. After 7 months, she was urgently re-hospitalized due to the complaint of abdominal pain. Her abdominal CT revealed the wall thickness and distention of the duplication as well as voluminous stool containing barium. After the improvement of her symptoms and on the basis of the inflammatory findings, laparoscopic surgery was performed on the patient. Finally, the lesion was diagnosed as tubular- and continuous-type colonic duplication. Duplication of the colon is a relatively rare occurrence in adulthood. Herein, we report a case of duplication of the sigmoid colon diagnosed prior to surgery in an adult.

Involvement of gut microbiota in association between GLP-1/GLP-1 receptor expression and gastrointestinal motility.

The microbiota in the gut is known to play a pivotal role in host physiology by interacting with the immune and neuroendocrine systems in gastrointestinal (GI) tissues. Glucagon-like peptide 1 (GLP-1), a gut hormone, is involved in metabolism as well as GI motility. We examined how gut microbiota affects the link between GLP-1/GLP-1 receptor (GLP-1R) expression and motility of the GI tract. Germ-free (GF) mice (6 wk old) were orally administered a fecal bacterial suspension prepared from specific pathogen-free (SPF) mice, and then after fecal transplantation (FT) GI tissues were obtained from the GF mice at various time points. The expression of GLP-1 and its receptor was examined by immunohistochemistry, and gastrointestinal transit time (GITT) was measured by administration of carmine red solution. GLP-1 was expressed in endocrine cells in the colonic mucosa, and GLP-1R was expressed in myenteric neural cells throughout the GI wall. GLP-1R-positive cells throughout the GI wall were significantly fewer in GF mice with FT than in GF mice without gut microbiota reconstitution. GITT was significantly shorter in GF mice with FT than in control GF mice without FT and correlated with the number of GLP-1R-positive cells throughout the GI wall. GITT was significantly longer in GF control mice than in SPF mice. When those mice were treated with GLP-1 agonist extendin4, GITT was significantly longer in the GF mice. The gut microbiota may accelerate or at least modify GI motility while suppressing GLP-1R expression in myenteric neural cells throughout the GI tract.NEW & NOTEWORTHY The gut microbiota has been intensively studied, because it plays a pivotal role in various aspects of host physiology. On the other hand, glucagon-like peptide 1 (GLP-1) plays important roles in metabolism as well as gastrointestinal motility. In the present study, we have suggested that the gut microbiota accelerates gastrointestinal motility while suppressing the expression of GLP-1 receptor in myenteric neural cells throughout the gastrointestinal tract. We believe that this article is very timely and suggestive work.

Evaluation of an e-learning system for diagnosis of gastric lesions using magnifying narrow-band imaging: a multicenter randomized controlled study.

Background and study aim Magnifying narrow-band imaging (M-NBI) is useful for the accurate diagnosis of early gastric cancer (EGC). However, acquiring skill at M-NBI diagnosis takes substantial effort. An Internet-based e-learning system to teach endoscopic diagnosis of EGC using M-NBI has been developed. This study evaluated its effectiveness. Participants and methods This study was designed as a multicenter randomized controlled trial. We recruited endoscopists as participants from all over Japan. After completing Test 1, which consisted of M-NBI images of 40 gastric lesions, participants were randomly assigned to the e-learning or non-e-learning groups. Only the e-learning group was allowed to access the e-learning system. After the e-learning period, both groups received Test 2. The analysis set was participants who scored < 80 % accuracy on Test 1. The primary end point was the difference in accuracy between Test 1 and Test 2 for the two groups. Results A total of 395 participants from 77 institutions completed Test 1 (198 in the e-learning group and 197 in the non-e-learning group). After the e-learning period, all 395 completed Test 2. The analysis sets were e-learning group: n = 184; and non-e-learning group: n = 184. The mean Test 1 score was 59.9 % for the e-learning group and 61.7 % for the non-e-learning group. The change in accuracy in Test 2 was significantly higher in the e-learning group than in the non-e-learning group (7.4 points vs. 0.14 points, respectively; P < 0.001). Conclusion This study clearly demonstrated the efficacy of the e-learning system in improving practitioners' capabilities to diagnose EGC using M-NBI.Trial registered at University Hospital Medical Information Network Clinical Trials Registry (UMIN000008569).

Adenosine triphosphate induces P2Y2 activation and interleukin-8 release in human esophageal epithelial cells.

BACKGROUND AND AIM: Immune-mediated mucosal inflammation characterized by the release of interleukin (IL)-8 is associated with gastroesophageal reflux disease. ATP released by human esophageal epithelial cells (HEECs) mediates the release of cytokines through P2 nucleotide receptors that are present on various cells, including HEECs. This study characterized and identified human esophageal epithelial P2 receptors that are responsible for ATP-mediated release of IL-8 by using a human esophageal stratified squamous epithelial model. METHODS: Primary HEECs were cultured with the use of an air-liquid interface (ALI) system. The ATP analogue adenosine 5'-O-3-thiotriphosphate (ATP-γ-S) was added to the basolateral compartment, and IL-8 release was measured. Involvement of the P2Y2 receptor was assessed with the use of selective and non-selective receptor antagonists and a P2Y2 receptor agonist. Expression of the P2Y2 receptor was assessed using western blotting and immunohistochemistry. RESULTS: Adenosine triphosphate-γ-S induced IL-8 release through the P2Y2 receptor. A P2Y2 receptor antagonist but not a P2X3 receptor antagonist or a P2Y1 receptor antagonist blocked ATP-γ-S-mediated IL-8 release. Conversely, a P2Y2 receptor agonist induced IL-8 release. Western blotting and immunohistochemistry of the P2Y2 receptor showed strong expression of the P2Y2 receptor on ALI-cultured HEECs and in human esophagus. Inhibition of extracellular signal-regulated kinase but not of protein kinase C blocked the ATP-mediated release of IL-8. ATP-γ-S induced phosphorylation of extracellular signal-regulated kinase, and a P2Y2 receptor antagonist blocked this phosphorylation. CONCLUSIONS: Interleukin-8 release after purinergic stimulation in ALI-cultured HEECs is mediated through P2Y2 receptor activation. ATP-induced IL-8 release maybe involved in the pathogenesis of refractory gastroesophageal reflux disease.

Effect of Vonoprazan, a Potassium-Competitive Acid Blocker, on the 13C-Urea Breath Test in Helicobacter pylori-Positive Patients.

BACKGROUND AND AIM: Vonoprazan (VPZ) is a new oral potassium-competitive acid blocker that has recently become available. The aim of this study was to investigate the effects of VPZ on the urease activity of H. pylori as measured by the 13C-urea breath test (13C-UBT). PATIENTS AND METHODS: A total of 60 patients (26 men, 34 women; mean age 53.2 ± 13.6 years) who were diagnosed as H. pylori-positive were recruited. The patients were randomly allocated to three treatment groups: lansoprazole (LPZ) 30 mg (n = 20), VPZ 20 mg (n = 20) once daily for 3 weeks, or the control group (n = 20). The 13C-UBT was carried out at baseline and after 3 weeks of treatment, and the baseline and after treatment results then compared. Δ13C‰ ≥ 2.5‰ was considered H. pylori-positive. RESULTS: Four patients failed to complete the medication and were omitted from the analysis; data from the LPZ group (n = 18), VPZ group (n = 18), and control group (n = 20) were analyzed. The control group showed no significant change in 13C-UBT data between baseline and the completion of 3-week treatment (baseline: 26.6 ± 23.0‰, completion: 21.1 ± 13.1‰). The 13C-UBT data at week 3 were significantly decreased in both the VPZ group (baseline: 32.8 ± 22.7‰, completion: 7.6 ± 9.2‰, p = 0.0002) and the LPZ group (baseline: 41.8 ± 33.4‰; completion: 9.6 ± 8.8‰, p = 0.0006) compared to baseline. CONCLUSIONS: VPZ treatment reduced the value of UBT, warning that UBT for patients with VPZ treatment should be evaluated carefully.

Claudin-2 expression is upregulated in the ileum of diarrhea predominant irritable bowel syndrome patients.

Intestinal epithelial barrier function is impaired in irritable bowel syndrome patients. Claudins are highly expressed in cells with tight junctions and are involved in the intestinal epithelial barrier function. The expression pattern of tight junction proteins in diarrhea-predominant irritable bowel syndrome have not been fully elucidated. We therefore recruited 17 diarrhea-predominant irritable bowel syndrome patients and 20 healthy controls. The expression of the tight junction-related proteins was examined in the ileal, cecal, and rectal mucosa of diarrhea-predominant irritable bowel syndrome patients using real-time PCR and immunofluorescence. Claudin-2 expression was high in the ileum of diarrhea-predominant irritable bowel syndrome patients. Claudin-2 expression was the same in cecum and rectal mucosa of control and diarrhea-predominant irritable bowel syndrome patients. Similarly, the expression of clauidn-1, claudin-7, JAM-A, occludin, and ZO-1 in the ileal, cecal, and rectal mucosa did not change between control and diarrhea-predominant irritable bowel syndrome samples. Infiltration of eosinophil and mast cells in the mucosa of ileum, cecum and rectum was evaluated using immunohistochemical staining and was not affected by diarrhea-predominant irritable bowel syndrome. Claudin-2 was expressed on the apical side of villi and crypts of ileal mucosal epithelial cells. Clauidn-2 expression is upregulated in diarrhea-predominant irritable bowel syndrome patients and may contribute to the pathogenesis of this condition.

Effects of Helicobacter pylori eradication on the development of metachronous gastric cancer after endoscopic treatment: analysis of molecular alterations by a randomised controlled trial.

BACKGROUND: Whether Helicobacter pylori eradication actually suppresses the development of metachronous gastric cancer (MGC) after endoscopic resection (ER) remains controversial. The aims of this study were to clarify (1) the molecular markers related to carcinogenesis in intestinal metaplasia (IM) by a cross-sectional study, and (2) the changes of those markers by an open-label, randomised controlled trial (RCT) of H. pylori treatment. METHODS: First, we evaluated microsatellite instability (MSI), the methylation status at hMLH1, CDKN2A and APC genes, and immunoreactivity using the monoclonal antibody (mAb) Das-1 in IM in the background mucosa of 131 patients who underwent ER for gastric neoplasia and 22 chronic gastritis cases (control). Next, we performed an RCT to evaluate the changes of MSI between the H. pylori-eradicated (n=19) and non-eradicated patients (n=17) at 1 year among the H. pylori-positive patients. RESULTS: Microsatellite instability and mAb Das-1 reactivity showed significantly higher incidences in both the H. pylori-positive and -negative patients compared with the control group, thus suggesting that MSI and mAb Das-1 reactivity are associated with gastric neoplasia (OR=5.06 for MSI; OR=2.51 for mAb Das-1 reactivity). The RCT showed that H. pylori eradication did not provide significant reversals of any molecular alterations including MSI (the primary end point) and other methylation statuses and mAb Das-1 reactivity (secondary end points). CONCLUSIONS: H. pylori eradication did not produce significant changes in the molecular alterations related to carcinogenesis, suggesting that H. pylori treatment may not prevent the development of MGC in background mucosa with IM.

Morphological Characteristics of Early Gastric Neoplasms Detected After Helicobacter pylori Eradication.

BACKGROUND: Previous morphological studies indicated that the eradication of Helicobacter pylori (H. pylori) made gastric neoplasms endoscopically indistinct through the flattening and covering of tumors with a non-neoplastic epithelium (NE). AIM: To validate these alterations. METHODS: We reviewed and compared the endoscopic and histological findings of early gastric carcinomas and high-grade dysplasias resected endoscopically from H. pylori-infected and H. pylori-eradicated patients. The extent of NE covering a tumor was expressed as the histological length ratio of NE to the tumor. Tumor morphology was compared before and after therapies in patients who received H. pylori eradication treatments during the period from tumor discovery to endoscopic resection. RESULTS: NE-covered ratios were higher in the 59 tumors detected after the eradication of H. pylori than in the 152 tumors detected during the infection (median 8 vs. 0 %, respectively), whereas the frequency at which an elevated morphology and whitish discoloration of a tumor were observed was less (14 vs. 56 %, and 14 vs. 43 %, respectively). These were also independent characteristics for tumors detected after the eradication of H. pylori. Two elevated tumors showing whitish discoloration out of 16 tumors became endoscopically indistinct following H. pylori eradication treatments through the flattening of tumors and muting of the discoloration. CONCLUSION: The eradication of H. pylori promoted covering with NE, the flattening of tumors, and muting of the whitish discoloration, which may make a subset of tumors, potentially including whitish elevated neoplasms, indistinct.

PAR-2 activation enhances weak acid-induced ATP release through TRPV1 and ASIC sensitization in human esophageal epithelial cells.

Esophageal visceral hypersensitivity has been proposed to be the pathogenesis of heartburn sensation in nonerosive reflux disease. Protease-activated receptor-2 (PAR-2) is expressed in human esophageal epithelial cells and is believed to play a role in inflammation and sensation. PAR-2 activation may modulate these responses through adenosine triphosphate (ATP) release, which is involved in transduction of sensation and pain. The transient receptor potential vanilloid receptor 1 (TRPV1) and acid-sensing ion channels (ASICs) are both acid-sensitive nociceptors. However, the interaction among these molecules and the mechanisms of heartburn sensation are still not clear. We therefore examined whether ATP release in human esophageal epithelial cells in response to acid is modulated by TRPV1 and ASICs and whether PAR-2 activation influences the sensitivity of TRPV1 and ASICs. Weak acid (pH 5) stimulated the release of ATP from primary human esophageal epithelial cells (HEECs). This effect was significantly reduced after pretreatment with 5-iodoresiniferatoxin (IRTX), a TRPV1-specific antagonist, or with amiloride, a nonselective ASIC blocker. TRPV1 and ASIC3 small interfering RNA (siRNA) transfection also decreased weak acid-induced ATP release. Pretreatment of HEECs with trypsin, tryptase, or a PAR-2 agonist enhanced weak acid-induced ATP release. Trypsin treatment led to the phosphorylation of TRPV1. Acid-induced ATP release enhancement by trypsin was partially blocked by IRTX, amiloride, or a PAR-2 antagonist. Conversely, acid-induced ATP release was augmented by PAR-2 activation through TRPV1 and ASICs. These findings suggested that the pathophysiology of heartburn sensation or esophageal hypersensitivity may be associated with the activation of PAR-2, TRPV1, and ASICs.

Expression of Reg family genes in the gastrointestinal tract of mice treated with indomethacin.

Regenerating gene (Reg) family proteins, which are classified into four types, commonly act as trophic and/or antiapoptotic factors in gastrointestinal (GI) diseases. However, it remains unclear how these proteins coordinate their similar roles under such pathophysiological conditions. Here, we investigated the interrelationships of Reg family gene expression with mucosal cell proliferation and apoptosis in nonsteroidal anti-inflammatory drug (NSAID)-induced GI injury. GI injury was induced by subcutaneous injection of indomethacin into Reg I knockout (KO) and wild-type (WT) mice, and its severity was scored histopathologically. Temporal changes in the expression of Reg family genes, mucosal proliferation, and apoptosis were evaluated throughout the GI tract by real-time RT-PCR, Ki-67 immunoreactivity, and TUNEL assay, respectively. Reg I, Reg III family, and Reg IV were predominantly expressed in the upper, middle, and lower GI mucosa, respectively. Expression of Reg I and Reg III family genes was upregulated in specific portions of the GI tract after indomethacin treatment. Ki-67-positive epithelial cells were significantly decreased in the gastric and small-intestinal mucosa of Reg I KO mice under normal conditions. After treatment with indomethacin, the number of TUNEL-positive cells was significantly greater throughout the GI mucosa in Reg I KO mice than in WT mice. Expression of Reg I was independent of that of other Reg family genes in, not only normal GI tissues, but also indomethacin-induced GI lesions. Members of the Reg gene family show distinct profiles of expression in the GI tract, and Reg I independently plays a role in protecting the GI mucosa against NSAID-induced injury.

The Nonsteroidal Anti-inflammatory Drug Diclofenac Reduces Acid-Induced Heartburn Symptoms in Healthy Volunteers.

BACKGROUND & AIMS: We investigated the effects of diclofenac, a nonsteroidal anti-inflammatory drug that inhibits prostaglandin production, on induction of esophageal sensation by acid perfusion in healthy men. METHODS: We performed a prospective, double-blind, placebo-controlled, 2-period, cross-over study over 3 visits in 12 healthy men. Diclofenac was given 6 hours and 2 hours before an acid perfusion test. During the test, hydrochloric acid (0.15 mol/L) was perfused into the lower esophagus for 30 minutes; we evaluated upper gastrointestinal symptoms using a validated categoric rating scale. Then, we calculated and assessed the acid perfusion sensitivity score (APSS). Biopsy specimens were collected by endoscopy of the distal esophagus before and after acid perfusion; levels of prostaglandin E2 (PGE2) (pg/mg) were measured in the samples using an enzyme-linked immunosorbent assay. RESULTS: Compared with placebo, diclofenac significantly reduced the APSS for heartburn (82.2 ± 12.2 for placebo and 47.5 ± 8.9 for diclofenac; P < .01). Of the upper gastrointestinal symptoms, only the APSS for heartburn was reduced significantly by diclofenac. Compared with placebo, diclofenac reduced the overproduction of PGE2 by esophageal tissues after acid perfusion (23.3 ± 5.2 for placebo and 11.4 ± 3.5 for diclofenac; P < .05). APSS correlated with the development of heartburn and esophageal levels of PGE2 (r = 0.53; P < .05 for heartburn vs PGE2). CONCLUSIONS: Diclofenac attenuated acid-induced heartburn by inhibiting PGE2 overproduction in the esophagus. Esophageal PGE2 might be involved in producing heartburn symptoms. Clinical Trials Registry no: UMIN000014595.

FGF9 from cancer-associated fibroblasts is a possible mediator of invasion and anti-apoptosis of gastric cancer cells.

BACKGROUND: Cancer-associated fibroblasts (CAFs), which reside around tumor cells, are suggested to play a pivotal role in tumor progression. Here we performed microarray analyses to compare gene expression profiles between CAFs and non-cancerous gastric fibroblasts (NGFs) from a patient with gastric cancer and found that fibroblast growth factor 9 (FGF9) was a novel growth factor overexpressed in CAFs. We then examined the biological effects of FGF9 during progression of gastric cancer. METHODS: Expression of FGF9 in CAFs and NGFs, and their secreted products, were examined by Western blotting. The effects of FGF9 on AGS and MKN28 gastric cancer cells in terms of proliferation, invasion and anti-apoptosis were assessed by WST-1 assay, invasion chamber assay and FACS, respectively. Furthermore, the intracellular signaling by which FGF9 exerts its biological roles was examined in vitro. RESULTS: FGF9 was strongly expressed in CAFs in comparison with NGFs, being compatible with microarray data indicating that FGF9 was a novel growth factor overexpressed in CAFs. Treatment with FGF9 promoted invasion and anti-apoptosis through activation of the ERK and Akt signaling pathways in AGS and MKN28 cells, whereas these effects were attenuated by treatment with anti-FGF9 neutralizing antibody. In addition, FGF9 treatment significantly enhanced the expression of matrix metalloproteinase 7 (MMP7) in both cell lines. CONCLUSIONS: FGF9 is a possible mediator secreted by CAFs that promotes the anti-apoptosis and invasive capability of gastric cancer cells.

Atypical symptoms and health-related quality of life of patients with asymptomatic reflux esophagitis.

BACKGROUND AND AIM: Asymptomatic reflux esophagitis (RE) is simply regarded as RE without the typical reflux symptoms, but it is unknown whether patients with asymptomatic RE have atypical symptoms. The aim of this study was to examine the clinical characteristics and health-related quality of life (HRQOL) of patients with asymptomatic RE. PATIENTS AND METHODS: Consecutive patients with RE were enrolled during January 2010 to August 2012, and of them, 41 who had taken acid-suppressing drugs were excluded, leaving 280 patients as the study group. The patients' symptoms were evaluated using a self-completed questionnaire (modified Frequency Scale for the Symptoms of gastroesophageal reflux disease [FSSG]), as well as an HRQOL questionnaire (SF-8). We defined the typical symptoms of RE as heartburn and regurgitation. Asymptomatic RE was defined if the total symptom score was 0 or the minimum (1 point) for typical reflux symptoms in the modified FSSG. RESULTS: Of the 280 RE patients, 71.8% (n = 201) were symptomatic and 28.2% (n = 79) were asymptomatic. The atypical symptom scores were significantly lower in asymptomatic RE (2.2 ± 2.2) than in symptomatic RE patients (6.9 ± 5.2) (P < 0.0001), and the HRQOL scores were significantly higher in asymptomatic RE than in symptomatic RE (P < 0.0001). Sleep was significantly less disturbed and chronic cough less frequent in asymptomatic RE than in symptomatic RE. CONCLUSION: Frequency and severity of atypical symptoms in patients with asymptomatic RE were significantly less than in patients with symptomatic RE, and the HRQOL score was significantly higher in those patients. These observations suggest a specific patient cohort that is truly unlikely to manifest symptoms.

Junctional adhesion molecule-A promotes proliferation and inhibits apoptosis of gastric cancer.

BACKGROUND/AIMS: Junctional adhesion molecules (JAMs) are known as integral constituents of cellular tight junctions. However, the functions of JAMs in cancer tissues are controversial and the function of JAM-A in gastric cancer is unclear. Acordingly, we investigated the function of JAM-A in gastric epithelial and gastric cancer cell proliferation, invasion and apoptosis. METHODOLOGY: A normal rat gastric mucosa-derived cell line (RGM1), a rat gastric cancer-like cell line established from RGM1 (RGK1), and a human gastric cancer cell line (NCI-N87) were used in this study. To examine the expression of junctional proteins, immunoblotting and immunofluorescent staining were performed with specific antibodies (JAM-A, claudins, occludin and ZO-1). JAM-A was knocked down by small interfering RNA. RESULTS: RGM1 and RGK1 expressed JAM-A, occludin and ZO-1 but not claudins. RGK1 were significantly more invasive than RGM1. JAM-A knock-down significantly decreased the proliferation and the invasion of RGK1 but not of RGM1. JAM-A knock-down significantly decreased the proliferation of NCI-N87 cells and significantly decreased expression of the anti-apoptotic protein Bcl-xL but not the expression of AKT or Mcl-1. CONCLUSIONS: JAM-A promotes proliferation and inhibits apoptosis of gastric cancer, suggesting that it has a pivotal role in gastric cancer progression.