[A case of cholangiolocellular carcinoma found to be hepatic hemangioma at 16-month follow up].

We report a rare case of hepatic cholangiolocellular carcinoma (CoCC) with long-term observation. A 73-year-old woman was found to have a solitary hepatic tumor with a diameter of 10mm on dynamic computed tomography (CT), which showed peripheral enhancement in the arterial phase and enhancement retention in the delayed phase. Although it was initially diagnosed as hepatic hemangioma, the follow up examination conducted 16 months later revealed that the tumor had grown to 18mm. Doubling time of the tumor was calculated to be 177 days. Because magnetic resonance imaging results were not typical for hepatic hemangioma, hepatocellular carcinoma was suspected and partial hepatectomy was performed. Histologically, the tumor was comprised dense proliferation of small irregular tubules with fibrous stroma. Immunohistochemistry revealed that the carcinoma cells were positive for cytokeratin (CK) 7, CK19, and neurnal cell adhesion molecule. Cells were negative for hepatocyte paraffin 1. Periodic acid-Schiff and Alcian blue staining showed an absence of mucin in the tumor cells, and epithelial membrane antigen was strongly positive on the luminal surface of tubules. These findings were typical of CoCC;therefore, CoCC should be ruled out when dynamic CT images suggest hepatic hemangioma.

[A case of a gas-forming liver abscess caused by Clostridium perfringens after transcatheter arterial chemoembolization].

An 80-year-old man had a medical history of chronic hepatitis C and pancreatoduodenectomy. We detected recurrence of hepatocellular carcinoma, and performed transcatheter arterial chemoembolization, instead of radiofrequency ablation or surgery, because of the patient's medical history of bile duct reconstruction and liver dysfunction. On the second day, he was diagnosed with a gas-forming liver abscess and underwent liver abscess drainage. Clostridium perfringens and sordellii were detected by aspiration and the blood culture. Meropenem and Clindamycin were administered intravenously. He was treated shortly after the occurrence before the involvement of severe hemolysis and recovered from the acute phase.

Association between endoscopic findings related to colonic diverticula and bowel habits: A multicenter study in Japan.

BACKGROUND AND AIM: Few studies have shown the associations between colonic diverticula and endoscopic findings such as location, inflammation, number of diverticula, sigmoid colon rigidity, and bowel habits. METHODS: Japanese subjects who underwent total colonoscopies at six centers in Japan from November 2015 to October 2016 were analyzed. Bowel habits were evaluated using the Gastrointestinal Symptom Rating Scale. Location and number of diverticula, inflammation, and sigmoid colon rigidity were evaluated from endoscopy results. RESULTS: A total of 762 subjects (486 men and 276 women [ratio, 1.76:1]) whose mean age was 65.5 ± 11.4 years were evaluated. In multivariate analysis, presence of constipation was associated with a significantly lower likelihood of left-sided colonic diverticula (odds ratio = 0.40, 95% confidence interval 0.20-0.82, P = 0.012), whereas right-sided and bilateral-sided colonic diverticula, multiple colonic diverticula, inflammation findings, and sigmoid colon rigidity were not related to bowel habits. CONCLUSIONS: Among endoscopic findings related to colonic diverticula and bowel habits, only left-sided colonic diverticula were inversely associated with constipation, whereas inflammation findings, multiple diverticula, and sigmoid colon rigidity were not related to bowel habits. However, the association of inflammation findings with colonic diverticula and bowel habits should be further studied. Investigation of changes in left-sided colonic diverticula may lead to new treatments for constipation.

[A case of gastrointestinal amyloidosis and hypoproteinemia improved by tocilizumab].

A woman in her 70s presented with dehydration and malnutrition due to watery diarrhea. She was examined and diagnosed with gastrointestinal amyloidosis accompanied by a protein-losing gastroenteropathy secondary to rheumatoid arthritis. She first underwent treatment with an anti-tumor necrosis factor alpha (TNF-α) antibody for secondary amyloidosis, but due to lack of adequate response, she was switched to an anti-interleukin (IL)-6 receptor antibody. Her clinical symptoms subsequently improved, and endoscopy revealed a marked decrease of amyloid protein deposits in the digestive tract. She was followed up for 3 years while continuing to receive the anti-IL-6 receptor antibody, with no recurrence. Although secondary amyloidosis is a fatal disease associated with chronic inflammatory diseases, clinical symptoms and prognosis have recently been improved by intervention with biological therapies. In particular, anti-IL-6 receptor antibodies have been reported to be superior to anti-TNF-α antibodies in the treatment of secondary amyloidosis and are expected to play a central role in treating secondary amyloidosis in the future.

A case of inoperable duodenal cancer achieving long-term survival after multidisciplinary treatment.

A 50-year-old female became aware of skin yellowing and consulted another hospital where she was diagnosed intraoperatively with duodenal cancer because of lymph node metastases around the aorta. Endoscopy revealed type IIa + IIc cancer distal to the duodenal papilla, and biopsy allowed a diagnosis of well-differentiated adenocarcinoma. Computed tomography revealed a large number of lymph node metastases around the aorta and in the left supraclavicular cavity. The patient was given many regimens of chemotherapy, mainly containing S-1, and multidisciplinary treatment, and achieved long-term survival for 6 years and 1 month. This is a valuable case suggesting the usefulness of this therapeutic approach. In view of the fact that duodenal cancer is a relatively rare disease and the possibility that the incidence of this disease may increase in the future, it seems essential to collect additional data from multicenter prospective studies towards the goal of establishing a standard method of treatment for this disease.

[A case of disseminated carcinomatosis of bone marrow with disseminated intravascular coagulation caused by advanced colon cancer treated by mFOLFOX6].

A 45-year-old man was admitted to our hospital because of disseminated intravascular coagulation syndrome (DIC) and severe pain in his back and lumbar. Abdominal CT scan demonstrated lymph node enlargement in the whole body. FDG-PET revealed abnormal uptake of FDG in the thickening wall of the descending colon and the entire skeleton. Colonoscopy was performed continuously and revealed a poorly-differentiated adenocarcinoma of the descending colon. He was treated with the systemic chemotherapy of modified FOLFOX6 (mFOLFOX6). After one course of the treatment, DIC was resolved and severe back pain and lumbargo were improved.

Proinflammatory role of protease-activated receptor-2 in intestinal ischemia/reperfusion injury in rats.

Protease-activated receptors (PARs) are widely recognized for their modulatory properties during inflammation. The aim of the present study was to examine the role of PAR-2 on ischemia/reperfusion-induced small intestinal injury in rats. Intestinal damage was induced in male Wistar rats by clamping both the superior mesenteric artery and the celiac trunk for 30 min, followed by reperfusion for 60 min. Expression of PAR-2 in the intestinal mucosa was estimated by Western blot analysis and real-time PCR. Anti-rat PAR-2 cleavage site (PCS) antibody was intraperitoneally administered to the rats 1 h before the vascular clamping. The intestinal mucosal injury and inflammation were evaluated by biochemical markers and histological findings. Thiobarbituric acid (TBA) reactive substances and tissue-associated myeloperoxidase (MPO) activity were measured in the intestinal mucosa as indices of lipid peroxidation and neutrophil infiltration, respectively. Expression of cytokine-induced neutrophil chemoattractant-1 (CINC-1) in intestinal mucosa was measured by enzyme-linked immunosorbent assay. Expression of PAR-2 mRNA and protein in the intestinal mucosa was increased after reperfusion following ischemia. Reperfusion after ischemia resulted in an increase in luminal protein concentrations, hemoglobin concentrations, TBA reactive substances, MPO activity and CINC-1 protein. Pre-treatment with anti-rat PCS antibody significantly inhibited the increases in these parameters. These results suggest that PAR-2 plays an important role in the pathogenesis of ischemia/reperfusion-induced intestinal injury.

Increased expression of microRNA in the inflamed colonic mucosa of patients with active ulcerative colitis.

BACKGROUND AND AIMS: MicroRNA (miRNA) are endogenous, approximately 22-nucleotide non-coding RNA that suppress gene expression at post-transcriptional levels by binding to the 3'-untranslated region of specific mRNA targets through base-pairing. It has been recently reported that miRNA have critical functions in key biological processes such as cell proliferation and cell death in various cancer cells. However, the relationship between intestinal inflammation and miRNA expression remains unclear. In the present study, we used microarray technology to identify miRNA induced in the colonic mucosa of patients with active ulcerative colitis (UC). METHODS: Two colonic biopsy specimens from patients with active stage (>Matts grade 2) of UC under colonoscopy and two colonic biopsy specimens from healthy volunteers were obtained for gene expression profiles. Total RNA was extracted, and miRNA expression profiles were investigated using miRNA Microarray. Subsequently, to confirm the result of the Microarray investigation, we checked the expression of several selected miRNA using real-time polymerase chain reaction (PCR) in 12 colonic biopsy specimens from patients with active UC under colonoscopy and 12 specimens from the healthy volunteers. RESULTS: In the microarray study, the expression of several miRNA was upregulated in the colonic mucosa of patients with active UC. Furthermore, two miRNA (miR-21, miR-155) were selected in the study using real-time PCR. CONCLUSION: Upregulated miRNA may be responsible for the development of intestinal inflammation in UC.

[A case of inflammatory myofibroblastic tumor of the lesser omentum with intratumoral hemorrhage].

A 24-year-old man presented complaining of epigastralgia and tenderness in the epigastric region. An abdominal computed tomography revealed a low density tumor, extending between the anterior wall of the stomach and the abdominal wall. Because the tumor was found to enlarge, an operation was performed to remove the tumor. During the operation, it was revealed that the tumor was connected with the lesser omentum, which suggested that it had originated from the lesser omentum. We diagnosed an inflammatory myofibroblastic tumor based on the pathological examination, which revealed infiltration of inflammatory cells, sparse proliferation of spindle cells and limited proliferation of collagen fibers, characterized by an irregular arrangement.

Synergistic effect of HLA class II loci and cytokine gene polymorphisms on the risk of gastric cancer in Japanese patients with Helicobacter pylori infection.

It has been reported that polymorphisms of human leukocyte antigen (HLA) genes and several cytokine genes are associated with an increased risk of developing gastric cancer (GC). However, the results of studies from different geographic regions, ethnic groups and study groups are inconsistent. The aim of this study was to evaluate the influence of H. pylori infection and host genetic factors on GC susceptibility in Japanese patients with GC. We analyzed genotypes for HLA class I and II, tumor necrosis factor alpha, interleukin (IL)-1beta, IL-1 receptor, IL-4, IL-4Ralpha and IL-10 in 330 H. pylori-infected noncardia patients with GC and 190 H. pylori-infected nonulcer dyspeptic controls. Haplotype analyses indicated that the frequencies of the HLA DRB1*0405 and DQB1*0401 alleles were increased in the patients with intestinal-type GC when compared with controls (both DRB1*0405 and DQB1*0401: p = 0.015, OR = 1.57, 95% CI = 1.09-2.26), but the changes were not statistically significant after correction for multiple comparisons. None of the cytokine gene polymorphisms were associated with GC susceptibility, whether patients with GC were analyzed as a group according to the histological subtype. Of interest was the comparison of controls and patients with intestinal-type GC. The frequency of an IL-10-592AA homozygote showing concomitant carriage of the HLA DRB1*0405-DQB1*0401 haplotype was significantly higher in patients with intestinal-type GC (chi(2) = 6.369, p = 0.0116, p(c) = 0.0464, OR = 2.43, 95% CI = 1.21-4.48). Our results suggest that the HLA class II and IL-10-592A/C polymorphisms synergistically affect the susceptibility to GC development of H. pylori-infected individuals in the Japanese population.

[A case of advanced gastric cancer with pulmonary carcinomatous lymphangitis responding remarkably to combination chemotherapy of docetaxel, CDDP and S-1].

A 31-year-old woman suffering from stomach pain was admitted to our hospital, and diagnosed with unresectable advanced gastric cancer. She was initially treated with combination therapy of S-1 and CDDP, and a partial response was achieved. After two courses of the chemotherapy, however, she complained of dyspnea, and pulmonary carcinomatous lymphangitis was confirmed by computed tomography. As second-line chemo-therapy, we attempted combination therapy with docetaxel, CDDP and S-1(DCS). After one course of the combination therapy, a remarkable response in the pulmonary carcinomatous lymphangitis was achieved. Treatment of patients with advanced gastric cancer associated with pulmonary carcinomatous lymphangitis is quite difficult and there is no scientific evidence to select anti-cancer drugs for these patients. We concluded that DCF could be a useful regimen for patients with gastric cancer associated with pulmonary carcinomatous lymphangitis.

Helicobacter pylori isolated from a patient with Ménétrier's disease increases hepatocyte growth factor mRNA expression in gastric fibroblasts: comparison with Helicobacter pylori isolated from other gastric diseases.

Ménétrier's disease has been reported to be associated with Helicobacter pylori infection. The aim of this study was to investigate the genetic characteristics of various virulence factors and cytokine expression profiles in Helicobacter pylori isolated from patients with Ménétrier's disease. The genotyping of virulence factors was accomplished by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Induction of various cytokines in MKN45 cells or gastric fibroblasts by Helicobacter pylori stimulus was measured by real-time reverse transcription-PCR. We found that the Helicobacter pylori strain isolated from a patient with Ménétrier's disease was different from other strains in the MseI-RFLP pattern of the ureC gene. Helicobacter pylori isolated from a patient with Ménétrier's disease showed the highest hepatocyte growth factor (HGF) and TNF-alpha mRNA expressions from gastric fibroblasts, and the highest TNF-alpha expression from MKN45 cells. The results in this study suggest that the difference in cytokine production, depending on the difference in bacteria components, plays an important role in the development of Ménétrier's disease.

Anti-tryptase treatment using nafamostat mesilate has a therapeutic effect on experimental colitis.

OBJECTIVE: Mast cell tryptase has been proposed to be involved in the pathogenesis of human inflammatory bowel disease (IBD). Recently, it was reported that a low dose of nafamostat mesilate (NM), a serine protease inhibitor that is widely used to treat disseminated intravascular coagulation (DIC) and acute pancreatitis, can selectively inhibit human tryptase activity. The aim of this study was to investigate the anti-inflammatory effects of NM on experimental colitis in rats. MATERIAL AND METHODS: Colitis was induced in male Wistar rats using an enema of trinitrobenzene sulfonic acid (TNBS) dissolved in 50% ethanol. NM or 5-aminosalicylic acid (5-ASA), foundation therapy for mild-to-moderate IBD, was administered via the anus once a day on each of the 6 days after administration of TNBS. Colonic inflammation was assessed 1 week after TNBS administration. RESULTS: Intracolonic administration of TNBS resulted in the infiltration of numerous tryptase-positive cells in the colonic mucosa. The colonic mucosal injury induced by TNBS was significantly decreased by treatment with NM or 5-ASA. The increases in thiobarbituric acid-reactive substances (TBA-RS), myeloperoxidase (MPO) activity, tumor necrosis factor (TNF)-alpha and cytokine-induced neutrophil chemoattractants-1 (CINC-1) in the colonic mucosa were inhibited in the NM group and the 5-ASA group, without significant differences between them. CONCLUSIONS: These results indicate that a low dose of NM can inhibit the colonic mucosal inflammation induced by TNBS in rats, which suggests that anti-tryptase therapy using low doses of NM has excellent potential to become a new therapeutic strategy for IBD.

Rosuvastatin, a new HMG-CoA reductase inhibitor, reduces the colonic inflammatory response in dextran sulfate sodium-induced colitis in mice.

The aim of the present study was to elucidate the beneficial effects of rosuvastatin, a new HMG-CoA reductase inhibitor, on colonic mucosal damage and on the inflammatory response in a dextran sulfate sodium (DSS) colitis model. Acute colitis was induced using 8% DSS in female BALB/c mice. Colonic mucosal inflammation was evaluated clinically, biochemically, and histologically. Mucosal protein contents and mRNA levels of tumor necrosis factor (TNF)-alpha were determined by immunoassay and real time-PCR. The mRNA levels of endothelial nitric oxide synthase (eNOS) were determined by real-time PCR. Disease activity scores in DSS-induced colitis model mice, as determined by weight loss, stool consistency, and blood in stool, were significantly lower in the rosuvastatin-treated mice than in control mice. Shortening of the colon was significantly reversed by rosuvastatin. Increases in tissue-associated myeloperoxidase activity and thiobarbituric acid-reactive substances after DSS administration were both significantly inhibited by treatment with rosuvastatin. Rosuvastatin also inhibited increases in intestinal TNF-alpha protein and mRNA expression after DSS administration, respectively. The mucosal mRNA levels of eNOS were decreased after DSS administration, but preserved in mice treated with rosuvastatin. These results suggest that rosuvastatin prevents the development of DSS-induced colitis in mice via the inhibition of mucosal inflammatory responses associated with the preservation of eNOS transcription.

CV-11974, angiotensin II type I receptor antagonist, protects against ischemia-reperfusion injury of the small intestine in rats.

BACKGROUND: Angiotensin II has been implicated in the pathogenesis of vascular inflammation in various organs. The aim of the present study was to examine the effect of angiotensin II type I receptor antagonist, CV-11974, on reperfusion-induced small intestinal injury in rats. METHODS: Intestinal damage was induced by clamping both the superior mesenteric artery and the celiac trunk for 30 min followed by reperfusion for 60 min in male Wistar rats. CV-11974 was given to the rats by intravenous injection 1 h before the vascular clamping. The intestinal mucosal injury and inflammation were evaluated by biochemical markers and histological findings. Thiobarbituric acid reactive substances and tissue-associated myeloperoxidase (MPO) activity were measured in the gastric mucosa as indices of lipid peroxidation and neutrophil infiltration. The expressions of pro-inflammatory cytokines (CINC-1) in intestinal mucosa were measured by enzyme-linked immunosorbent assay (ELISA) and reverse transcription-PCR (RT-PCR). In additional experiments with an in vitro flow system, human neutrophils were perfused on human umbilical vein endothelial cells (HUVEC) pretreated with anoxia-reoxygenation with or without CV-11974 and then the adhesive neutrophils were counted. RESULTS: Reperfusion after ischemia resulted in an increase in luminal protein concentrations, hemoglobin concentrations, thiobarbituric acid reactive substances, and MPO activity. Pretreatment with CV-11974 significantly inhibited the increases in these parameters. CV-11974 also inhibited increases in intestinal CINC-1 protein and mRNA expression induced by ischemia-reperfusion. Moreover, in an in vitro study, CV-11974 significantly inhibited the adherence of neutrophils to HUVEC exposed to reoxygenation after anoxia. CONCLUSIONS: These results suggest that the blockade of angiotensin II type I receptor by treatment with CV-11974 remarkably reduced the reperfusion-induced intestinal injury.

A novel water-soluble vitamin E derivative protects against aspirin-induced gastric mucosal injury in rats.

Oxygen radical-mediated lipid peroxidation and neutrophil activation may be involved in the development of gastric mucosal injury induced by non-steroidal anti-inflammatory drugs (NSAIDs). Vitamin E is one of the lipid-soluble antioxidants and is generally considered to protect against lipid peroxidation of the cell membrane and to scavenge singlet oxygen and superoxide anion radicals. Our object was to investigate the antioxidative effects of water-soluble vitamin E derivative, 2-(alpha-D-glucopyranosyl)methyl-2,5,7,8-tetra-methylchroman-6-ol (TMG), on aspirin-induced gastric mucosal injury in rats. Gastric injury was induced by intragastric administration of aspirin and 0.15 N HCl in male Sprague-Dawley rats. TMG dissolved in physiological saline was injected intraperitoneally 0.5 h before the aspirin administration. The intragastric administration of acidified aspirin induced hyperemia and hemorragic erosions in rat stomach. The increase in total area of gastric erosions was reduced by pretreatment with TMG in a dose-dependent manner. The increases of thiobarbituric acid-reactive substances (TBA-RS) and myeloperoxidase (MPO) activity 3 h after aspirin administration were significantly inhibited by pretreatment with TMG. The gastric concentration of cytokine-induced neutrophil chemoattractants-1 (CINC-1) increased after aspirin administration, and the increase was also inhibited by pretreatment with TMG. These results suggest that TMG is effective for the treatment of aspirin-induced gastric injury. This anti-inflammatory effect of TMG seems to be related to impairment of lipid peroxidation, neutrophil function and cytokine production in gastric mucosa.

Prevention by rebamipide of acute reflux esophagitis in rats.

Proinflammatory factors, including neutrophil-derived oxygen free radicals and inflammatory cytokines, have recently been implicated in the pathogenesis of reflux esophagitis. Rebamipide has been widely used as an anti-ulcer agent. The aim of the present study was to assess the protective effect of rebamipide against acute reflux esophagitis in rats. Esophagitis was induced in rats by ligation at the limiting ridge and the lower portion of the duodenum. Vehicle or rebamipide were given as a single dose intraduodenally. Lesion index (LI), thiobarbituric acid-reactive substances (TBA-RS), myeloperoxidase (MPO) activity, mRNA and protein of tumor necrosis factor (TNF)-alpha and cytokine-induced neutrophil chemoattractant (CINC)-1 in the esophageal mucosa were markedly increased; pretreatment with rebamipide, however, significantly reduced both macroscopic and microscopic injuries and increases in inflammatory mediators. The results of this study indicate that rebamipide protects against the occurrence of esophagitis and has highly promising potential as a new therapeutic agent for reflux esophagitis.

A comparative study on endoscopic ulcer healing of omeprazole versus rabeprazole with respect to CYP2C19 genotypic differences.

Omeprazole is mainly metabolized in the liver by CYP2C19, a genetically determined enzyme, while rabeprazole is mainly nonenzymatically degraded with a minor involvement by CYP2C19. We investigated the gastric ulcer healing effect of omeprazole versus rabeprazole evaluated endoscopically with reference to the different CYP2C19 genotypes. Eighty patients with active gastric ulcer were treated with a daily dose of 20 mg of omeprazole or 10 mg of rabeprazole. The endoscopic evaluation was performed at the baseline and 2- and 8-week posttreatment periods. The endoscopic improvement of gastric ulcer size and ulcer healing rates using a thin rubber disc with a diameter of 6 mm, were evaluated in relation to the CYP2C19 genotypic status. The mean 2-week posttreatment ulcer size value by rabeprazole did not significantly differ among the different CYP2C19 genotypes, whereas the mean value in the homozygous extensive metabolizer patients treated with omeprazole was significantly (P = 0.0057) greater than in those with rabeprazole. However, after the 8-week treatment, omeprazole and rabeprazole showed the similarly high healing rates of 87.8% (31/37) and 88.9% (32/36), respectively. Although both omeprazole and rabeprazole showed a high healing rate of gastric ulcer after the 8-week treatment period, the healing effect of rabeprazole appears to be relatively independent of the CYP2C19 status, resulting in an earlier repair of gastric mucosal damage evaluated endoscopically compared to that of omeprazole.

A novel potent inhibitor of inducible nitric oxide inhibitor, ONO-1714, reduces intestinal ischemia-reperfusion injury in rats.

The overproduction of nitric oxide (NO) by inducible nitric oxide synthase (iNOS) may contribute to the pathophysiology of intestinal injury induced by ischemia-reperfusion. The aim of the present study was to examine the effect of selective iNOS inhibition by a cyclic amidine analogue, ONO-1714, on reperfusion-induced small intestinal injury and inflammation in rats. 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. The luminal nitrite concentration in the small intestine was measured by Griess reaction and the iNOS mRNA expression by RT-PCR. The severity of the intestinal mucosal injury and inflammation were evaluated by several biochemical markers and by the histological findings. The rats which were killed after ischemia-reperfusion had increased luminal concentrations of nitrite and iNOS mRNA expression, in addition to severe intestinal inflammation characterized by significant increases in myeloperoxidase activity, a marker of neutrophil infiltration, and by the mucosal content of CINC-1 cytokine, a neutrophil chemotactic cytokine. Administration with ONO-1714 significantly inhibited the luminal NO production. Reperfusion after 30-min ischemia resulted in an increase in luminal protein and hemoglobin concentrations, with levels reaching a maximum after 60 min of reperfusion. In contrast, pre-treatment with ONO-1714 2h before the ischemia inhibited the increases in luminal protein and hemoglobin concentration in a dose-dependent manner (0.001-0.1mg/kg). The contents of the thiobarbituric acid-reactive substances (a marker of oxidative lipid peroxidation) were significantly increased by ischemia-reperfusion, and this increase was reduced by ONO-1714. After reperfusion, the increase in tissue-associated myeloperoxidase activity, an index of neutrophil infiltration, was significantly inhibited by pre-treatment with ONO-1714. ONO-1714 also inhibited increases in intestinal CINC-1 protein and mRNA expression, as determined by ELISA and RT-PCR, respectively. In conclusion, the improvement of reperfusion-induced intestinal injury by ONO-1714 suggested that an excess of NO, produced by iNOS, may have contributed to the initiation/amplification of intestinal inflammatory injury by various mechanisms, including nitrosative and oxidative damage as well as the enhancement of inflammatory cytokine release.

A PPAR-gamma ligand, 15-deoxy-Delta12,14-prostaglandin J(2), inhibited gastric mucosal injury induced by ischemia-reperfusion in rats.

INTRODUCTION: Recent studies have demonstrated the anti-inflammatory action of 15-deoxy-Delta12,14-prostaglandin J(2) (15d-PGJ(2)), a derivative of the PGD(2) metabolic pathway. Acute inflammation, including neutrophil activation, plays a critical role in the pathogenesis of ischemia-reperfusion (I/R). The aim of the present study was to determine the effect of 15d-PGJ(2) on I/R-induced gastric mucosal injury in rats. METHODS: Gastric mucosal damage was induced in male Wistar rats by clamping the celiac artery for 30 min followed by reperfusion. 15d-PGJ(2) (0.01-1.0 mg/kg) was given to the rats intraperitoneally 1 h before the vascular clamping. The area of gastric mucosal erosions (erosion index) was measured. Thiobarbituric acid reactive substances (TBARS) and tissue-associated myeloperoxidase (MPO) activity were measured in the gastric mucosa as indices of lipid peroxidation and neutrophil infiltration. The expression of tumor necrosis factor-alpha (TNF-alpha) in gastric mucosa was measured by ELISA. In addition, to elucidate whether the protective effects of 15d-PGJ(2) are related to the activation of the PPAR-gamma receptor, we also investigated the effects of a PPAR-gamma antagonist, GW9662. RESULTS: After 60 min of reperfusion, the area of gastric erosion index had significantly increased from the mean basal levels. The increase in the erosion index was significantly inhibited by pretreatment with 15d-PGJ(2) in a dose-dependent manner. On the other hand, GW9662 reversed the protective effect of 15d-PGJ(2). The concentration of TBARS and MPO activity in the gastric mucosa were both significantly increased after I/R, and pretreatment with 15d-PGJ(2) significantly reduced these increases. The TNF-alpha content was significantly higher in the I/R group than in the sham-operated group. However, the increase in TNF-alpha was significantly inhibited by pretreatment with 15d-PGJ(2). CONCLUSIONS: 15d-PGJ(2) significantly inhibited the severity of acute gastric mucosal injury induced by I/R in rats through PPAR-gamma-dependent mechanisms. This effect may be due, in part, to a reduction in the infiltration of neutrophils into the gastric mucosa, possibly via the inhibition of inflammatory cytokine.