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161.
Cardiomyopathies indistinctly affect atrial and ventricular cardiac compartments with alterations of their mechanical and/or electrical activity. To understand the main mechanisms involved in these pathological alterations, a detailed knowledge of the physiology of the healthy heart is critical. In the present work, we utilize multidimensional protein identification technology to characterize the murine left ventricle (LV), right ventricle (RV), and atria (A) proteomes, identifying thousands of distinct proteins. Moreover, using multidimensional algorithm protein map tool, relative abundances of proteins among the heart chambers were investigated. In sum, we found 16 and 55 proteins were more abundant in LV compared to RV and A, respectively; 47 and 60 proteins were more abundant in RV than LV and A, respectively; and, 81 and 74 proteins were more abundant in A than LV and RV, respectively. This detailed characterization of myocardial compartment proteome represents an important advancement in the knowledge of heart physiology, and may contribute to the identification of key features underlying the onset of cardiomyopathy. 相似文献
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Limana F Esposito G D'Arcangelo D Di Carlo A Romani S Melillo G Mangoni A Bertolami C Pompilio G Germani A Capogrossi MC 《PloS one》2011,6(6):e19845
Aims
HMGB1 injection into the mouse heart, acutely after myocardial infarction (MI), improves left ventricular (LV) function and prevents remodeling. Here, we examined the effect of HMGB1 in chronically failing hearts.Methods and Results
Adult C57 BL16 female mice underwent coronary artery ligation; three weeks later 200 ng HMGB1 or denatured HMGB1 (control) were injected in the peri-infarcted region of mouse failing hearts. Four weeks after treatment, both echocardiography and hemodynamics demonstrated a significant improvement in LV function in HMGB1-treated mice. Further, HMGB1-treated mice exhibited a ∼23% reduction in LV volume, a ∼48% increase in infarcted wall thickness and a ∼14% reduction in collagen deposition. HMGB1 induced cardiac regeneration and, within the infarcted region, it was found a ∼2-fold increase in c-kit+ cell number, a ∼13-fold increase in newly formed myocytes and a ∼2-fold increase in arteriole length density. HMGB1 also enhanced MMP2 and MMP9 activity and decreased TIMP-3 levels. Importantly, miR-206 expression 3 days after HMGB1 treatment was 4-5-fold higher than in control hearts and 20–25 fold higher that in sham operated hearts. HMGB1 ability to increase miR-206 was confirmed in vitro, in cardiac fibroblasts. TIMP3 was identified as a potential miR-206 target by TargetScan prediction analysis; further, in cultured cardiac fibroblasts, miR-206 gain- and loss-of-function studies and luciferase reporter assays showed that TIMP3 is a direct target of miR-206.Conclusions
HMGB1 injected into chronically failing hearts enhanced LV function and attenuated LV remodelling; these effects were associated with cardiac regeneration, increased collagenolytic activity, miR-206 overexpression and miR-206 -mediated inhibition of TIMP-3. 相似文献165.
Di Meglio P Di Cesare A Laggner U Chu CC Napolitano L Villanova F Tosi I Capon F Trembath RC Peris K Nestle FO 《PloS one》2011,6(2):e17160
IL-23 and Th17 cells are key players in tissue immunosurveillance and are implicated in human immune-mediated diseases. Genome-wide association studies have shown that the IL23R R381Q gene variant protects against psoriasis, Crohn's disease and ankylosing spondylitis. We investigated the immunological consequences of the protective IL23R R381Q gene variant in healthy donors. The IL23R R381Q gene variant had no major effect on Th17 cell differentiation as the frequency of circulating Th17 cells was similar in carriers of the IL23R protective (A) and common (G) allele. Accordingly, Th17 cells generated from A and G donors produced similar amounts of Th17 cytokines. However, IL-23-mediated Th17 cell effector function was impaired, as Th17 cells from A allele carriers had significantly reduced IL-23-induced IL-17A production and STAT3 phosphorylation compared to G allele carriers. Our functional analysis of a human disease-associated gene variant demonstrates that IL23R R381Q exerts its protective effects through selective attenuation of IL-23-induced Th17 cell effector function without interfering with Th17 differentiation, and highlights its importance in the protection against IL-23-induced tissue pathologies. 相似文献
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Many decades of scientific investigation have proved the role of selective pressure in Homo Sapiens at least at the level of individual genes or loci. Nevertheless, there are examples of polygenic traits that are bound to be under selection, but studies devoted to apply population genetics methods to unveil such occurrence are still lacking. Stature provides a relevant example of well-studied polygenic trait for which is now available a genome-wide association study which has identified the genes involved in this trait, and which is known to be under selection. We studied the behavior of FST in a simulated toy model to detect population differentiation on a generic polygenic phenotype under selection. The simulations showed that the set of alleles involved in the trait has a higher mean FST value than those undergoing genetic drift only. In view of this we looked for an increase in the mean FST value of the 180 variants associated to human height. For this set of alleles we found FST to be significantly higher than the genomic background (p = 0.0356). On the basis of a statistical analysis we excluded that the increase was just due to the presence of outliers. We also proved as marginal the role played by local adaptation phenomena, even on different phenotypes in linkage disequilibrium with genetic variants involved in height. The increase of FST for the set of alleles involved in a polygenic trait seems to provide an example of symmetry breaking phenomenon concerning the population differentiation. The splitting in the allele frequencies would be driven by the initial conditions in the population dynamics which are stochastically modified by events like drift, bottlenecks, etc, and other stochastic events like the born of new mutations. 相似文献
168.
Di Paola R Caporarello N Marucci A Dimatteo C Iadicicco C Del Guerra S Prudente S Sudano D Miele C Parrino C Piro S Beguinot F Marchetti P Trischitta V Frittitta L 《PloS one》2011,6(5):e19462
The aim of this study was to deeper investigate the mechanisms through which ENPP1, a negative modulator of insulin receptor (IR) activation, plays a role on insulin signaling, insulin secretion and eventually glucose metabolism. ENPP1 cDNA (carrying either K121 or Q121 variant) was transfected in HepG2 liver-, L6 skeletal muscle- and INS1E beta-cells. Insulin-induced IR-autophosphorylation (HepG2, L6, INS1E), Akt-Ser(473), ERK1/2-Thr(202)/Tyr(204) and GSK3-beta Ser(9) phosphorylation (HepG2, L6), PEPCK mRNA levels (HepG2) and 2-deoxy-D-glucose uptake (L6) was studied. GLUT 4 mRNA (L6), insulin secretion and caspase-3 activation (INS1E) were also investigated. Insulin-induced IR-autophosphorylation was decreased in HepG2-K, L6-K, INS1E-K (20%, 52% and 11% reduction vs. untransfected cells) and twice as much in HepG2-Q, L6-Q, INS1E-Q (44%, 92% and 30%). Similar data were obtained with Akt-Ser(473), ERK1/2-Thr(202)/Tyr(204) and GSK3-beta Ser(9) in HepG2 and L6. Insulin-induced reduction of PEPCK mRNA was progressively lower in untransfected, HepG2-K and HepG2-Q cells (65%, 54%, 23%). Insulin-induced glucose uptake in untransfected L6 (60% increase over basal), was totally abolished in L6-K and L6-Q cells. GLUT 4 mRNA was slightly reduced in L6-K and twice as much in L6-Q (13% and 25% reduction vs. untransfected cells). Glucose-induced insulin secretion was 60% reduced in INS1E-K and almost abolished in INS1E-Q. Serum deficiency activated caspase-3 by two, three and four folds in untransfected INS1E, INS1E-K and INS1E-Q. Glyburide-induced insulin secretion was reduced by 50% in isolated human islets from homozygous QQ donors as compared to those from KK and KQ individuals. Our data clearly indicate that ENPP1, especially when the Q121 variant is operating, affects insulin signaling and glucose metabolism in skeletal muscle- and liver-cells and both function and survival of insulin secreting beta-cells, thus representing a strong pathogenic factor predisposing to insulin resistance, defective insulin secretion and glucose metabolism abnormalities. 相似文献
169.
Sperandeo MP Tosco A Izzo V Tucci F Troncone R Auricchio R Romanos J Trynka G Auricchio S Jabri B Greco L 《PloS one》2011,6(7):e21281
Background and Aim
Potential celiacs have the ‘celiac type’ HLA, positive anti-transglutaminase antibodies but no damage at small intestinal mucosa. Only a minority of them develops mucosal lesion. More than 40 genes were associated to Celiac Disease (CD) but we still do not know how those pathways transform a genetically predisposed individual into an affected person. The aim of the study is to explore the genetic features of Potential CD individuals.Methods
127 ‘potential’ CD patients entered the study because of positive anti-tissue transglutaminase and no mucosal lesions; about 30% of those followed for four years become frankly celiac. They were genotyped for 13 polymorphisms of ‘candidate genes’ and compared to controls and celiacs. Moreover, 60 biopsy specimens were used for expression studies.Results
Potential CD bear a lighter HLA-related risk, compared to celiac (χ2 = 48.42; p value = 1×10−8). They share most of the polymorphisms of the celiacs, but the frequency of c-REL* G allele was suggestive for a difference compared to celiac (χ2 = 5.42; p value = 0.02). One marker of the KIAA1109/IL-2/IL-21 candidate region differentiated potentials from celiac (rs4374642: χ2 = 7.17, p value = 0.01). The expression of IL-21 was completely suppressed in potentials compared to celiacs (p value = 0.02) and to controls (p value = 0.02), in contrast IL-2, KIAA1109 and c-REL expression were over-expressed.Conclusions
Potential CD show genetic features slightly different from celiacs. Genetic and expression markers help to differentiate this condition. Potential CD is a precious biological model of the pathways leading to the small intestinal mucosal damage in genetically predisposed individuals. 相似文献170.
This paper concerns the Circular Dichroism (CD) and Nuclear Magnetic Resonance (NMR) structural studies of the quadruple helix arrangements adopted by three tailored oligodeoxyribonucleotide analogues, namely d(TGMeGGT), d(TGGMeGT) and d(TGGGMeT), where dGMe represents a 8-methyl-2′-deoxyguanosine residue. The results of this study clearly demonstrate that the effects of the incorporation of dGMe instead of a dG residue are strongly dependant upon the positioning of a single base replacement along the sequence. As such, d(TGMeGGT), d(TGGMeGT) have been found to form 4-fold symmetric quadruplexes with all strands parallel and equivalent to each other, each more stable than their natural counterpart. NMR experiments clearly indicate that [d(TGMeGGT)]4 possesses a GMe-tetrad with all dGMe residues in a syn-glycosidic conformation while an anti-arrangement is apparent for the four dGMe of [d(TGGMeGT)]4. As the two complexes show a quite different CD behaviour, a possible relationship between the presence of residues adopting syn-glycosidic conformations and CD profiles is briefly discussed. As far as d(TGGGMeT) is concerned, NMR data indicate that at 25°C it exists primarily as a single-strand conformation in equilibrium with minor amounts of a quadruplex structure. 相似文献