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sphenotype at diagnosis (B1±p) (87.2%). Of the 16 tag-SNPs, allelic and/or genotype associ-ations were noted for five SNPs (all p<0.05). No overall haplotype associations were notedwhen all 16 SNPs or the 5 SNPs with suggestions of significant associations in the singleSNP analysis were considered. MDR analysis suggested significant interactions between theCARD15, ATG16L1 and the rs2542170 and rs973767 SNPs in the PTPN2 gene (p<0.001)Conclusions Our gene-wide analysis suggests that the PTPN2 gene may be associated withpediatric-onset CD. Interestingly, in the presence of CARD15 and ATG16L1, the gene appearsto be more strongly associated with CD. Further studies to examine pathways linking thebiological actions of the three genes are required.

S1755

H. pylori Infection and Small Intestine Bacterial Overgrowth in Patients withFabry' Disease: Do They Enhance the Expression of Fabry'-RelatedGastrointestinal Symptoms?Francesco Franceschi, Giovanni Gigante, Davide Roccarina, Anna Zampetti, DanielaAntuzzi, Giovanna Vitale, Maria Elena Ainora, Valentina Cesario, Cristiano Lauritano,Guido De Marco, Bianca Giupponi, Veronica Ojetti, Federico Barbaro, Claudio Feliciani,Giovanni Gasbarrini, Antonio Gasbarrini, Nicolò Gentiloni Silveri

Background: Fabry's disease (FD) is a genetic disorder characterized by an accumulation ofglycosphingolipids, which in the GI tract causes motility disfunction. While an early occur-rence of upper and lower GI symptoms has already been described, there is a high interindi-vidual variability either before or after alpha-galactosidase replacement therapy. H. pyloriinfection and small intestine bacterial overgrowth (SIBO) are frequent causes of upper andlower GI symptoms, respectively; Whether they may enhance the expression of GI symptomsin FD patients is still unclear. Methods: 12 consecutive FD patients (8 males, mean age35±5) and 12 healthy sex and age-matched subjects underwent glucose-breath test (GBT)to detect SIBO and 13C Urea breath test (UBT) to detect H. pylori. Prevalence of epigastricpain, abdominal discomfort, nausea, bloating, flatulence, constipation and diarrhea wereassessed. χ2 Yates test was used for statistical analysis. Results: GBT was positive in 6 FDpatients and in 1 control (p<0.005), while UBT showed positivity in 7 FD patients and in3 controls (p<0.004). Abdominal discomfort, bloating, and flatulence were significantlyhigher in SIBO-positive patients compared with SIBO-negative (p<0.01), while epigastricpain and nausea were significantly increased in H. pylori positive patients compared tonegative (p<0.002). Conclusions: This study report for the first time a higher prevalence ofH. pylori infection in FD patients, who also show an increased prevalence of SIBO, determiningan increased expression of Fabry'-related GI symptoms. The impairment of the GI tractmotility, typical of Fabry' disease patients, may create a favourable environment for bothH. pylori gastric colonization and SIBO.

S1756

High Cumulative Risk of Intussusceptions in Patients with Peutz-JeghersSyndromeMargot G. van Lier, Anja Wagner, A. M. Westerman, F. W. de Rooij, John H. Wilson,Ernst J. Kuipers, M. E. Leerdam van

Background: Peutz-Jeghers Syndrome (PJS) is an inherited disorder characterized by gastroin-testinal hamartomas and mucocutaneous pigmentation. A germline mutation in the STK11gene can be found in 70% of clinically affected patients. The hamartomas are mainly locatedin the small bowel and may cause complications, in particular intussusception. Since balloon-enteroscopy (BE) enables endoscopic removal of small bowel polyps, we assessed genotype-phenotype correlations and the risk and onset of intussusception.Methods: Patients diagnosedwith PJS based on clinical diagnostic criteria or proven STK11 mutation were included inthis prospective cohort study (1995-Nov 2008). Clinical data including sex, date of birthand death, diagnosis of PJS, STK11 mutation status, family history, diagnosis of intussuscep-tion, and PJS-related surgical interventions were obtained by interview and chart-review.Genotype-phenotype correlations were evaluated. The cumulative risk of intussusceptionwas calculated by Kaplan-Meier analyses. Results: 44 PJS patients (57% males) were includedout of 18 PJS families; 32 patients still alive had a median age of 44 years (10-74 yrs) and12 patients had deceased at a median age of 45 years (11-73 yrs). A germline STK11mutation had been detected in 32 patients (73%). Regardless of indication 41 patients (93%)had undergone at least 1 PJS-related operation (1-17) at a median age at the first surgeryof 14.5 years (3-50 yrs). 34 patients (77%) had a history of one or more episodes ofintussusception (1-6) due to small bowel polyps (one malignant degenerated polyp). Themedian age at which the first intussusception had occurred was 13.5 years (3-50 yrs).Surgery was required in 33 (75%) patients, whereas in 1 case the invagination resolvedspontaneously. There was no significant difference in intussusception incidence accordingto sex (p=0.15) or mutation-status (p=0.70). Kaplan Meier analyses showed that intussuscep-tion had occurred in 50% of the cohort at a median age of 16 years (95% CI 11-21), increasingto 75% (95% CI 62-88) at the age of 35 yrs. The 10 year probability of intussusception was25% (95% CI 12-38). Conclusion: PJS patients carry a high cumulative risk of intussusception(50% at 16 yrs) caused by small bowel hamartomas. The incidence of intussusception is notinfluenced by STK11 mutation status. These findings support the approach of enteroscopicsurveillance with timely removal of small bowel hamartomas. The effect of this approachon the incidence of intussusception (as well as malignant degeneration) remains to beestablished and weighted against the burden and complication risk of the intervention.

A-264AGA Abstracts

S1757

TAMPs: A Tight Junction Protein Family with Non-Redundant FunctionsDavid R. Raleigh, Yong Zhang, Amanda M. Marchiando, Yingmin Wang, Le Shen,Manyuan Long, Jerrold R. Turner

The MARVEL (MAL and related proteins for vesicle trafficking and membrane link) domainis a conserved tetra-span structure found in a diverse array of proteins responsible forapposition of cholesterol-richmembrane microdomains. In epithelial cells, MARVEL domain-containing proteins decorate intracellular and apical membranes. Two of these proteins,occludin and tricellulin, localize to the tight junction and contribute to barrier function.The aims of this study were to define the complete family of tight junction-associatedMARVEL proteins (TAMPs) and determine their functional roles. METHODS: All humanMARVEL domain protein sequences were obtained from the EMBL-EBI InterPro databaseto establish a comprehensive list of candidate TAMPs. MARVEL protein localization wasassessed using EGFP-tagged forms in Caco-2 human intestinal epithelial cells as well as byimmunofluorescence and SDS-PAGE immunoblot of Caco-2 cells and mouse jejunum. TAMPsynthesis and trafficking was studied during tight junction assembly in Caco-2 monolayers.RESULTS: Phylogenetic analysis of human MARVEL proteins divides these into four evolu-tionary groups, where occludin, tricellulin, and a previously uncharacterized gene product,marvelD3, segregate into a single family. EGFP-marvelD3 is concentrated at bicellular tightjunctions, similar to occludin, but, unlike tricellulin, is not specifically enriched at tricellulartight junctions. Immunofluorescent microscopy of Caco-2 monolayers and mouse intestinedemonstrates identical localization of endogenous marvelD3. In contrast, proteins from theother three MARVEL groups are present at apical membranes and within intracellular vesiclesbut not at intercellular junctions in Caco-2monolayers. SDS-PAGE immunoblots demonstrateexpression of endogenous marvelD3 in Caco-2 cells, mouse intestinal epithelia, and epithelialorgans (intestine, liver, kidney, lung) but not in non-epithelial organs (heart, muscle, brain),similar to occludin and tricellulin. Moreover, marvelD3 expression is induced during epithe-lial polarization and junction assembly in a manner that parallels that of occludin andtricellulin. Trafficking of each TAMP to the tight junction coincides with development ofbarrier function. siRNA knockdown of occludin, tricellulin, or marvelD3 expression delaysbarrier development in Caco-2 monolayers, suggesting that each TAMP is necessary for tightjunction assembly and barrier function. CONCLUSIONS: MarvelD3 completes the TAMPfamily and contributes to barrier function by a mechanism that is not complemented byoccludin or tricellulin. We therefore conclude that marvelD3 is a unique and essential tightjunction component.

S1758

Curcumin Selectively Inhibits VCAM-1 Expression in Human IntestinalMicrovascular Endothelial Cells (HIMEC)David G. Binion, Jan Heidemann, Mona S. Li, Vicky M. Nelson, Parvaneh Rafiee

INTRODUCTION: Endothelial surface expression of cell adhesion molecules (CAMs) iscritical for leukocyte recruitment and binding during the initiation and maintenance of aninflammatory response. Previously we have shown that CAM synthesis and expression inprimary cultures of human intestinal microvascular endothelial cells (HIMEC) is regulatedby the transcription factor NFκB. Vascular cell adhesionmolecule-1 (VCAM-1) is an inducibleCAM found on endothelial and mesenchymal cells in the human intestine. VCAM-1 is aligand for alpha4 expressing leukocytes, and is appreciated to play a critical role in animalmodels of inflammatory bowel disease (IBD). Inhibition of alpha4 leukocyte binding hasproven efficacy in IBD with the compound natalizumab. Curcumin, a major component ofthe spice turmeric has shown clinical therapeutic effect in human IBD. Curcumin exerts aninhibitory effect on NFκB and MAPK signaling cascades in various cell types. In this study,we investigated the effect of curcumin, PI3K/Akt andMAPK inhibitors on VCAM-1 expressionand function in HIMEC. METHODS: CAM expression was assessed using biotinylatedantibodies and I125 streptavidin. HIMEC- leukocyte adhesion was visualized under staticand flow conditions. Cell lysates were analyzed by Western blotting using specific phospho-antibodies to MAPK and Akt. NFκB activation and its p65 subunit translocation to thenucleus was determined. RESULTS: TNF-α/LPS-induced VCAM-1 expression in HIMECwas abolished by curcumin, and inhibitors of NFκB (SN-50), JNK (SP600125) and PI3K/Akt (LY294002). VCAM-1 induction was partially suppressed by p44/42 MAPK inhibition(PD098059), but remained unaffected by p38 MAPK inhibition (SB203580). Western blotanalysis showed that curcumin inhibited Akt/MAPK/ NFκB activity and prevented nucleartranslocation of the NFκB subunit p65. At physiological shear stress, curcumin attenuatedleukocyte adhesion to HIMEC monolayers following TNF-α/LPS activation. CONCLUSION:Curcumin inhibited the expression of VCAM-1in HIMECs through blockade of PI3K/Akt,JNK and NFκB activity. The therapeutic effect of the plant derivative curcumin in IBD mayinvolve downregulating endothelial CAM expression and inhibition of endothelial ligandinteraction with alpha4 integrin.

S1759

NHE3 and NHERF2 Bind Dynamically At the Epithelial Brush Border inResponse to Elevated Ca2+, Revealed By FRETXinjun C. Zhu, Boyoung Cha, Nicholas C. Zachos, Rafiquel Sarker, Debbie Steplock,Edward Weinman, Mark Donowitz, Olga Kovbasnjuk

Background/Aim: Regulated absorption and secretion in the gastrointestinal and renal systemsallow maintenance of body water and Na homeostasis. The BB Na+/H+ exchanger, NHE3is rapidly activated or inhibited by dietary, neurohumoral substances, growth factors, andsecond messengers in the intestine during normal digestion. This regulation depends onplasma membrane protein-protein interactions that involve NHE3 and the NHE regulatoryfactor gene family (NHERFs), which are required for NHE3 inhibition by cAMP, cGMP andCa. Under basal conditions, the NHERFs, especially NHERF2, directly bind NHE3 and limitits mobility in the BB. However, second messenger inhibition of NHE3 is associated withtransiently increased BB mobility. Because NHE3 and NHERF2 are both localized at thebrush border, we thus hypothesized that NHERF2 may dynamically interact with NHE3,