The CTLA4 variants may interact with the IL23R- and NOD2-conferred risk in development of Crohn's disease

<p>Abstract</p> <p>Background</p> <p>The <it>CTLA4 </it>(cytotoxic T-lymphocyte antigen 4) gene is associated with several immunopathologic diseases and because of its important immuno-regulatory role it may be considered also a plausible candidate for a genetic association with inflammatory bowel diseases. Previously published studies found no association of <it>CTLA4 </it>with Crohn's disease itself, but some indicated an association with its subphenotypes. The aim of this study was to assess the association in the Czech population, using a set of markers shown to associate with other diseases.</p> <p>Methods</p> <p>Six polymorphisms within the <it>CTLA4 </it>region were investigated in 333 patients with Crohn's disease and 482 unrelated healthy controls, all Caucasians of Czech origin. The genotypes of the SNPs were determined using the TaqMan SNP genotyping assays. Haplotypes were reconstructed using an expectation-maximization algorithm, and their association with the condition was assessed using log-linear modeling. Then, potential interactions were tested between the <it>CTLA4 </it>variants and other genetic factors known to confer the disease susceptibility.</p> <p>Results</p> <p>No crude associations with Crohn's disease were found for the tested <it>CTLA4 </it>variants under the log-additive or dominant models. However, when stratified for the genetic risk conferred by the variants in the <it>NOD2 </it>(the p.Leu1007fsX1008, rs5743293) or the <it>IL23R </it>(p.R381Q, rs11209026), a significant negative association emerged for the minor alleles of <it>CTLA4 </it>CT60 (rs3087243), JO31 (rs11571302), JO27-1 (rs11571297) polymorphisms. This negative association with <it>CTLA4 </it>was apparent only in the strata defined by presence minor alleles at the <it>NOD2 </it>rs5743293 (here the <it>CTLA4 </it>CT60 A coffered an OR = 0.43, 95%CI 0.19 - 0.95 for the presence of CT60 A), or <it>IL23R </it>rs11209026 (here the OR for presence of CT60 A was 0.23, 95%CI 0.07 - 0.71). We observed this effect also for the haplotype consisting of minor alleles of the three tightly linked <it>CTLA4 </it>markers. Furthermore, this haplotype was associated with the younger age at diagnosis (OR 1.52, 95%CI 1.09 - 2.11, p = 0.014).</p> <p>Conclusions</p> <p>A protective effect of a <it>CTLA4 </it>haplotype was unmasked after stratification for the risk variants in the <it>NOD2 </it>and <it>IL23R </it>genes, and may point towards the biological relevance of the molecule in the pathogenesis of the disease.</p

The role of endoscopic retrograde cholangiopancreatography in choledochal cysts and/or abnormal pancreatobiliary junction in children

Introduction : Biliary cysts with an abnormal pancreatobiliary junction are one of the most common pancreatobiliary malformations. The main symptom is cholestasis; endoscopic retrograde cholangiopancreatography (ERCP) plays a key role in diagnosis. Aim : Retrospective evaluation of ERCP performed to diagnose abnormalities of the pancreatobiliary junction. Material and methods : We retrospectively evaluated ERCP performed to diagnose abnormalities of the pancreatobiliary junction, mainly choledochal cysts, in 112 children between 1990 and 2011. Results : We performed 112 examinations of 50 children with abnormal pancreatobiliary junction and choledochal cysts (15 males and 35 females, average age: 5 years, range: 1 month – 15 years). Cysts were associated with a common channel in 37 (74%) cases, were not associated with a common channel in 9 (18%) cases, and in 3 (6%) cases the common channel lacked cysts. We performed endoscopic papilla sphincterotomy on 33 (66%) patients; endoscopic drainage was performed 62 times, including 17 patients without papilla sphincterotomy. In 15 (30%) cases, we only performed sphincterotomy. Extraction of lithiasis was done in 2 (4%) cases. Both ERCP and magnetic resonance cholangiopancreatography (MRCP) were performed on 13 patients. There was concordance of the choledochal cyst and of the type of cyst in both methods; however, common channels could not be observed by MRCP. There was 1 serious complication (perforation after sphincterotomy) and 11 (9%) mild adverse events. Conclusions : When performed at an expert centre, ECRP is a safe and reliable procedure for children with choledochal cysts and/or an abnormal pancreatobiliary junction. Endoscopic retrograde cholangiopancreatography remains a reasonable alternative because MRCP has a limited ability to diagnose the precise anomalies of the pancreatobiliary junction and has no therapeutic capabilities

SIRT1-dependent modulation of methylation and acetylation of histone H3 on lysine 9 (H3K9) in the zygotic pronuclei improves porcine embryo development

Abstract Background The histone code is an established epigenetic regulator of early embryonic development in mammals. The lysine residue K9 of histone H3 (H3K9) is a prime target of SIRT1, a member of NAD+-dependent histone deacetylase family of enzymes targeting both histone and non-histone substrates. At present, little is known about SIRT1-modulation of H3K9 in zygotic pronuclei and its association with the success of preimplantation embryo development. Therefore, we evaluated the effect of SIRT1 activity on H3K9 methylation and acetylation in porcine zygotes and the significance of H3K9 modifications for early embryonic development. Results Our results show that SIRT1 activators resveratrol and BML-278 increased H3K9 methylation and suppressed H3K9 acetylation in both the paternal and maternal pronucleus. Inversely, SIRT1 inhibitors nicotinamide and sirtinol suppressed methylation and increased acetylation of pronuclear H3K9. Evaluation of early embryonic development confirmed positive effect of selective SIRT1 activation on blastocyst formation rate (5.2 ± 2.9% versus 32.9 ± 8.1% in vehicle control and BML-278 group, respectively; P ≤ 0.05). Stimulation of SIRT1 activity coincided with fluorometric signal intensity of ooplasmic ubiquitin ligase MDM2, a known substrate of SIRT1 and known limiting factor of epigenome remodeling. Conclusions We conclude that SIRT1 modulates zygotic histone code, obviously through direct deacetylation and via non-histone targets resulting in increased H3K9me3. These changes in zygotes lead to more successful pre-implantation embryonic development and, indeed, the specific SIRT1 activation due to BML-278 is beneficial for in vitro embryo production and blastocyst achievement