Riichiro Nezu

Alteration of Vβ Usage and Cytokine Production of CD4+ TCR ββ Homodimer T Cells by Elimination of Bacteroides vulgatus Prevents Colitis in TCR α-Chain-Deficient Mice

A major pathogenic factor for the development of inflammatory bowel disease (IBD) is the breakdown of the intestinal homeostasis between the host immune system and the luminal microenvironment. To assess the potential influence of luminal Ags on the development of IBD, we fed TCR α−/− mice an elemental diet (ED). ED-fed TCR α−/− mice showed no pathologic features of IBD, and their aberrant mucosal B cell responses were suppressed. Similar numbers of CD4+, TCR ββ homodimer T cells (ββ T cells) were developed in the colonic mucosa of ED-fed mice; however, Th2-type cytokine productions were lower than those seen in diseased regular diet (RD)-fed mice. The higher cytokine production in diseased RD-fed mice could be attributed to the high incidence of Bacteroides vulgatus (recovered in 80% of these mice), which can induce Th2-type responses of colonic CD4+, ββ T cells. In contrast, ED-fed TCR α−/− mice exhibited a diversification of Vβ usage of ββT cell populations from the dominant Vβ8 one associated with B. vulgatus in cecal flora to Vβ6, Vβ11, and Vβ14. Rectal administration of disease-free ED-fed mice with B. vulgatus resulted in the development of Th2-type CD4+, ββ T cell-induced colitis. These findings suggest that the ED-induced alteration of intestinal microenvironments such as the enteric flora prevented the development of IBD in TCR α−/− mice via the immunologic quiescence of CD4+, ββ T cells.

Serum leucine-rich alpha-2 glycoprotein is a disease activity biomarker in ulcerative colitis

Background: Reliable biomarkers for monitoring disease activity have not been clinically established in ulcerative colitis (UC). This study aimed to investigate whether levels of serum leucine‐rich alpha‐2 glycoprotein (LRG), identified recently as a potential disease activity marker in Crohns disease and rheumatoid arthritis, correlate with disease activity in UC. Methods: Serum LRG concentrations were determined by enzyme‐linked immunosorbent assay (ELISA) in patients with UC and healthy controls (HC) and were evaluated for correlation with disease activity. Expression of LRG in inflamed colonic tissues from patients with UC was analyzed by western blotting and immunohistochemistry. Interleukin (IL)‐6‐independent induction of LRG was investigated using IL‐6‐deficient mice by lipopolysaccharide (LPS)‐mediated acute inflammation and dextran sodium sulfate (DSS)‐induced colitis. Results: Serum LRG concentrations were significantly elevated in active UC patients compared with patients in remission (P < 0.0001) and HC (P < 0.0001) and were correlated with disease activity in UC better than C‐reactive protein (CRP). Expression of LRG was increased in inflamed colonic tissues in UC. Tumor necrosis factor alpha (TNF‐&agr;), IL‐6, and IL‐22, serum levels of which were elevated in patients with active UC, could induce LRG expression in COLO205 cells. Serum LRG levels were increased in IL‐6‐deficient mice with LPS‐mediated acute inflammation and DSS‐induced colitis. Conclusions: Serum LRG concentrations correlate well with disease activity in UC. LRG induction is robust in inflamed colons and is likely to involve an IL‐6‐independent pathway. Serum LRG is thus a novel serum biomarker for monitoring disease activity in UC and is a promising surrogate for CRP. (Inflamm Bowel Dis 2012;)

Laparoscopic intragastric surgery for gastric leiomyoma

Abstract. Laparoscopic intragastric surgery (LIGS) was performed on a 63-year-old man with a gastric leiomyoma adjacent to the cardia. Because the tumor was about 5 cm in maximum diameter and showed ulceration, the possibility that the tumor was a leiomyosarcoma could not be ruled out preoperatively. Conventionally, major surgery has been performed on patients with a tumor located near the cardia, although it was not always malignant. Enucleation by LIGS enabled us to avoid excessive invasiveness and provided a favorable result. LIGS may be an appropriate new, minimally-invasive operation for gastric myogenic tumors and should be considered for such cases.

Total parenteral nutrition decreases luminal mucous gel and increases permeability of small intestine.

The distribution of fluorescein isothiocyanate dextran 70,000 (FITC-dextran) and mucous gel across the lumen of small intestine was observed as an investigation into the role of mucous gel on permeability in total parenteral nutrition (TPN). Thirty-two rats were randomly divided into two groups fed with either TPN or oral rat food. On day 4 or 7, FITC-dextran (750 mg/kg body weight) was given through the gastroduodenal tube. After 1 hour, blood samples were taken by aortic puncture to analyze plasma FITC-dextran by fluorescence spectrometry. Samples of small intestine with luminal contents were frozen and sectioned in a cryostat for fluorescence microscopy; the same sections were placed in a 0.2% celloidin solution for 3 minutes to preserve mucous gel and stained by periodic acid-Schiff reaction for light microscopy. The plasma level of FITC-dextran after 1 hour of this marker injection showed a significant increase (p < .01) in the TPN group compared with the rat food group on days 4 and 7. Morphologic findings on days 4 and 7 were similar in both the jejunum and ileum: The mucous gel filled the spaces between villi and FITC-dextran centered in the lumen in the rat food group, whereas the mucous gel decreased and FITC-dextran filled the spaces between villi in the TPN group. FITC-dextran and mucous gel showed complementary distributions in both groups. These data suggest that TPN decreases luminal mucous gel and increases permeability of small intestine in rats.

The effect of metronidazole on TPN-associated liver dysfunction in neonates

The effect of metronidazole (MNZ) on hepatic dysfunction associated with total parenteral nutrition (TPN) in neonates was investigated. Neonates receiving TPN for more than 2 weeks were divided into three groups. In group 1, TPN was given alone, in group 2, 25 mg/kg/d of MNZ was administered intravenously for the first 2 weeks of TPN, and in group 3, 50 mg/kg/d of MNZ was given for the first 3 weeks of TPN. Several parameters of liver function tests (LFTs) during the first 4 weeks of TPN were compared among these three groups. There was no significant difference of these parameters between group 1 and group 2. Although there was no significant difference of alkaline phosphatase, gamma-glutamyl transpeptidase, direct bilirubin, and total bile acid between groups 1 and 3, transaminase (glutamic oxaloacetic, glutamic pyruvic) of group 3 remained significantly lower than those of group 1. In conclusion, the administration of MNZ 50 mg/kg/d for 3 weeks, at least, prevented the elevation of transaminase during TPN in neonates, suggesting the possible involvement of intestinal anaerobic flora in the pathogenesis of TPN-associated liver dysfunction.

Influence of glutamine-supplemented parenteral nutrition on intestinal amino acid metabolism in rats after small bowel resection.

Glutamine (Gln)-supplemented total parenteral nutrition (TPN) has been shown to improve mucosal adaptation after massive small bowel resection (SBR); however, its influences on intestinal amino acid metabolism remain unknown. In this study, intestinal amino acid flux, circulating plasma aminogram, mucosal glutaminase activity and protein, and DNA content were measured 7 days after massive SBR in rats receiving either standard (Std) or Gln-supplemented TPN. Sham-operated rats and rats fed chow after enterectomy served as controls. The uptake of Gln and the release of citrulline (Cit) by the remaining intestine was significantly decreased, with reduced mucosal glutaminase activity after SBR in the Chow and Std-TPN groups. Glutamine supplementation resulted in significantly increased gut Gln uptake compared with Std-TPN (P<0.01). Mucosal glutaminase activity, mucosal protein, and DNA content was also increased by Gln; however, the gut release of Cit remained unchanged (P>0.05). The subsequent decrease in circulating arginine (Arg) in the Gln-TPN group compared with the Std-TPN group (P<0.05) was attributed to an insufficient exogenous supply. These findings show that Gln-supplemented TPN improves mucosal growth and gut Gln uptake after SBR. However, the intestinal production of Cit, which remained low in both TPN groups, may lead to an insufficiency of endogenous Arg synthesis. Thus, both Gln and Arg may be essential amino acids after SBR.

Hyperbilirubinemia in neonates associated with total parenteral nutrition

To identify the factors responsible for total parenteral nutrition (TPN) associated jaundice in the neonate, 77 newborns who had been started on TPN during the past 12 years had their charts reviewed. Forty-four (57%) of these infants developed jaundice during the 1st month of life. The incidence of jaundice was significantly higher in the presence of those diseases which were associated with impaired intestinal passage such as congenital duodenal atresia, jejunal atresia, etc, and those with an abnormal rotation of the gut such as diaphragmatic hernia, gastroschisis, etc. Thirty-two (42%) of these 77 infants had accompanying infectious signs, and 28 (88%) of those 32 infants with infectious signs developed jaundice. This incidence was significantly higher than that (36%) among those who had no infectious signs. Of the possible etiologic factors other than infection, neither the length of intrauterine life nor birth weight showed significant correlation with the incidence of jaundice. The incidence of jaundice tended to be higher in infants started on TPN at a younger age. There was no significant correlation between the incidence of jaundice and the duration of TPN or fasting period. Infants receiving 110 cal/kg/day or more during TPN developed jaundice significantly more frequently than those receiving fewer calories. No definite correlation was obtained between the incidence of jaundice and the amount of amino acids administered.

Beneficial effects of growth hormone combined with parenteral nutrition in the management of inflammatory bowel disease: an experimental study.

BACKGROUND Growth hormone (GH) improves net protein anabolism and stimulates wound healing. Although GH is also known to exert the trophic effect on the intestinal tract, its role in the healing of intestinal ulceration is not known. The aim of this study was to evaluate the effects of exogenous GH coinfused with parenteral nutrition (PN) in an experimental model of inflammatory bowel disease in rats. METHODS All rats underwent central venous cannulation and were randomized to two groups after induction of small intestinal ulceration with indomethacin. Both groups received the same PN formula. In addition, the GH group (n = 10) received subcutaneous injections of human GH at a dose of 1.0 IU/kg daily for 4 days, whereas the control group (n = 10) received injections of normal saline solution. Nitrogen balance, macroscopic inflammation score, intestinal myeloperoxidase activity, DNA content, and mucosal permeability were determined for each rat. Insulin-like growth factor-I (IGF-I) mRNA was detected by reverse transcription and polymerase chain reaction. RESULTS Administration of GH significantly improved the cumulative nitrogen balance, ameliorated the gross inflammation score, and decreased intestinal myeloperoxidase activity. Similarly, intestinal permeability was significantly decreased in the GH group as compared with the control group. GH treatment resulted in increased plasma concentration of IGF-I and IGF-I mRNA expressions in both the liver and the small intestine compared with those in the control group. CONCLUSIONS Exogenous GH plays an important role in accelerating intestinal healing in an experimental model of small bowel ulceration in rats. The mechanisms may include the stimulated IGF-I production, which thereafter augments intestinal epithelial cell growth.

Laparoscopic-assisted surgery for crohn’s disease: Reduced surgical stress following ileocolectomy

Recent progress in laparoscopic techniques has enabled operations for various intestinal disorders to be performed under laparoscopic assistance. This study was conducted to assess the benefits of performing laparoscopicassisted surgery (LAS) in patients with Crohn’s disease. LAS was performed in 24 selected patients with Crohn’s disease, most of whom underwent ileocolic resection for ileitis and/or colitis with stenosis. To determine the benefits of LAS, the postoperative inflammatory parameters of these patients were examined and compared with those of 17 patients who underwent conventional open surgery. Despite giving all patients total parenteral nutrition (TPN) for more than 2 weeks preoperatively, two patients with large inflammatory masses involving enteroenteric fistulas required conversion to laparotomy. No laparoscopic procedure was converted for adhesions after previous resection or intraoperative complications. The maximum C-reactive protein values and body temperatures were significantly lower, and the time taken to normalize body temperature and leukocyte counts was significantly shorter in the LAS group than in the laparotomy group. LAS should be performed for patients with Crohn’s disease in the inactive phase after appropriate nutritional support. Patients with terminal ileitis without a fistula are considered to have the highest indication for this procedure.

Advantages of laparoscope-assisted surgery for recurrent Crohn's disease

BackgroundLaparoscopic surgery has been applied to patients with primary Crohns disease, and its beneficial outcomes have been already investigated. However, there is no systematic study of laparoscopic surgery for patients with recurrent diseases.MethodsWe performed reoperation for 43 patients with recurrent Crohns disease, including 23 patients who underwent laparoscope-assisted surgery.ResultsFor all the patients, laparoscope-assisted surgery could be performed safely, even if the patients had been treated previously by open surgery or had undergone multiple abdominal procedures. Conversion to open or hand-assisted laparoscopic surgery was necessary for 16 patients (69.6%) because of dense adhesions (11 cases) or bulky tumor (5 cases). Importantly, even if the procedure was converted, the skin incision was significantly shorter than with open surgery, and postoperative recovery was faster, especially for the patients who underwent conversion to hand-assisted laparoscopic surgery.ConclusionsLaparoscope-assisted surgery is feasible and advantageous in reoperation for patients with recurrent Crohns disease.