Angiogenesis within the duodenum of patients with cirrhosis is modulated by mechanosensitive Kruppel-like factor 2 and microRNA-126.

BACKGROUND: The mechanism involved in neovascularization in splanchnic circulation and the main trigger that induces angiogenesis in patients with cirrhosis are not fully recognized. AIMS: To explore the involvement of flow sensitive lung Kruppel-like factor (KLF2), microRNA-126 (miR-126), angiopoietin-2 (Ang-2) and heme oxygenase-1 (HO-1) in modulation of vascular endothelial growth factor (VEGF) signalling that have a critical effect on growth of new blood vessels. METHODS: Duodenal biopsies from 22 patients with cirrhosis and 10 controls were obtained during routine endoscopy. The process of angiogenesis was evaluated by a measurement of CD31 concentration, immunodetection of CD34 protein and estimation of capillary densities. Messenger RNA (mRNA) and protein expressions were analysed by real-time PCR, Western blot or ELISA respectively. RESULTS: Markers of angiogenesis (both, CD31 and CD34) were significantly enhanced in cirrhotic patients. In comparison to healthy controls, levels of Ang-2 and KLF-2 mRNAs as well as Ang-2, KLF-2, HO-1, VEGF protein expressions were considerably increased. Levels of sCD163, a surrogate marker of portal hypertension, correlated with levels of Ang-2, (P = 0.021) and VEGF (P = 0.009). The expression of miR-126, a KLF2-mediated regulator of the VEGF signalling was enhanced in cirrhotic patients. CONCLUSIONS: Our results demonstrate, for the first time in humans, that neovascularization is induced in duodenal tissue of patients with cirrhosis and proangiogenic factors such as KLF-2, Ang-2, miR-126 and VEGF can contribute to the angiogenesis induced by hemodynamic forces. Thus, cirrhosis-induced blood flow and pressure within splanchnic vessels may be important hemodynamic triggers that initiate the angiogenic signalling cascade.

NOD2/CARD15 mutations in Polish and Bosnian populations with and without Crohn's disease: prevalence and genotype-phenotype analysis.

Data on prevalence and phenotypic consequences of nucleotide-binding oligomerisation domain 2/caspase recruitment domains 15 (NOD2/CARD15) variants in Crohn's disease (CD) population in Poland and Bosnia and Herzegovina (B&H) are nonexistent. We aimed to determine the prevalence of NOD2/CARD15 mutations and their association with disease phenotype in Polish and Bosnian patients with CD and in healthy controls. We prospectively recruited 86 CD patients and 83 controls in Poland and 30 CD patients and 30 controls in B&H, 229 in total. We determined the prevalence of NOD2/CARD15 mutations and their association with the disease phenotype according to Montreal classification. Participants were genotyped for Leu1007fsinsC and Gly908Arg mutations. At least one CD-associated allele was found in 29/86 (33.7%) of Polish CD patients and in 9/83 (10.8%) of healthy controls (p<0.001). In both CD patients and controls in Bosnian sample, at least one NOD2 mutation was found in equal number of patients (3/30; 10%) with all of the NOD2 mutation positive CD patients being homozygous, while controls being heterozygous. In Polish sample, perianal disease was less frequent in CD patients with any NOD2 mutation (1/21; 4.8%) compared to those without (11/41; 26.8%; p=0.046). Higher percentage of patients with NOD2 mutations had history of CD related surgery when compared with those without mutations (66.7% vs. 43.3%; p=0.05). The risk for CD is increased in patients with NOD2 mutations (Poland) and especially in the presence of homozygous NOD2 mutations (Poland and Bosnia). The presence of variant NOD2 alleles is associated with increased need for surgery and reduced occurrence of perianal disease.