Suppressor of Cytokine Signaling-3 (SOCS-3) induces Proprotein Convertase Subtilisin Kexin Type 9 (PCSK9) expression in hepatic HepG2 cell line

The suppressor of cytokine signaling (SOCS) proteins are negative regulators of the JAK/STAT pathway activated by proinflammatory cytokines, including the tumor necrosis factor (TNF-\u3b1). SOCS3 is also implicated in hypertriglyceridemia associated to insulin resistance. Proprotein convertase subtilisin kexin type 9 (PCSK9) levels are frequently found to be positively correlated to insulin resistance and plasma very low density lipoprotein (VLDL) triglycerides concentrations. The present study aimed to investigate the possible role of TNF-\u3b1 and JAK/STAT pathway on de novo lipogenesis and PCSK9 expression in HepG2 cells. TNF-\u3b1 induced both SOCS3 and PCSK9 in a concentration-dependent manner. This effect was inhibited by transfection with siRNA anti-STAT3, suggesting the involvement of the JAK/STAT pathway. Retroviral overexpression of SOCS3 in HepG2 cells (HepG2SOCS3) strongly inhibited STAT3 phosphorylation and induced PCSK9 mRNA and protein, with no effect on its promoter activity and mRNA stability. Consistently, siRNA anti-SOCS3 reduced PCSK9 mRNA levels, whereas an opposite effect was observed with siRNA anti- STAT3. In addition, HepG2SOCS3 express higher mRNA levels of key enzymes involved in the de novo lipogenesis, such as fattyacid synthase, stearoyl-CoA desaturase (SCD)-1, and apoB. These responses were associated with a significant increase of SCD-1 protein, activation of sterol regulatory element-binding protein-1c (SREBP-1), accumulation of cellular triglycerides, and secretion of apoB. HepG2SOCS3 show lower phosphorylation levels of insulin receptor substrate 1 (IRS-1) Tyr896 and Akt Ser473 in response to insulin. Finally, insulin stimulation produced an additive effect with SOCS3 overexpression, further inducing PCSK9, SREBP-1, fatty acid synthase, and apoB mRNA. In conclusion, our data candidate PCSK9 as a gene involved in lipid metabolism regulated by proinflammatory cytokine TNF- in a SOCS3-dependent manner

Computational fluid dynamics models and congenital heart diseases

Mathematical modeling is a powerful tool to investigate hemodynamics of the circulatory system. With improving imaging techniques and detailed clinical investigations, it is now possible to construct patient-specific models of reconstructive surgeries for the treatment of congenital heart diseases. These models can help clinicians to better understand the hemodynamic behavior of different surgical options for a treated patient. This review outlines recent advances in mathematical modeling in congenital heart diseases, the discoveries and limitations these models present, and future directions that are on the horizon

Computational fluid dynamics models and congenital heart diseases

Mathematical modeling is a powerful tool to investigate hemodynamics of the circulatory system. With improving imaging techniques and detailed clinical investigations, it is now possible to construct patient-specific models of reconstructive surgeries for the treatment of congenital heart diseases. These models can help clinicians to better understand the hemodynamic behavior of different surgical options for a treated patient. This review outlines recent advances in mathematical modeling in congenital heart diseases, the discoveries and limitations these models present, and future directions that are on the horizon

Beyond Income and Inequlity: The Role of Socio-Political Factors for Alleviating Energy Poverty in Europe

In each country, the occurrence of energy poverty among resident households is usually related to low income and its unequal distribution. Like other manifestations of material deprivation, however, such a phenomenon is likely to be also correlated with some internal socio-political factors that allow its persistence by preventing effective solutions. In this paper, we build and analyse a dataset for European countries by assessing the role of the perceived quality of internal public governance on different measures of energy deprivation. Specifically, we rely on the Worldwide Governance Indicators provided by the World Bank and estimate an array of panel models. After controlling for income, income inequality, energy prices, and weather conditions, we find that high government effectiveness, good regulatory quality, widespread property rights, contract enforcement, and corruption control are significantly associated with lower energy poverty. In addition, we consider the policy implications of this broader perspective on energy deprivation

PCSK9 induces a pro-inflammatory response in macrophages

Intraplaque release of inflammatory cytokines from macrophages is implicated in atherogenesis by inducing the proliferation and migration of media smooth muscle cells (SMCs). PCSK9 is present and released by SMCs within the atherosclerotic plaque but its function is still unknown. In the present study, we tested the hypothesis that PCSK9 could elicit a pro-inflammatory effect on macrophages. THP-1-derived macrophages and human primary macrophages were exposed to different concentrations (0.250\u2009\uf7\u20092.5\u2009\ub5g/ml) of human recombinant PCSK9 (hPCSK9). After 24\u2009h incubation with 2.5\u2009\ub5g/ml PCSK9, a significant induction of IL-1\u3b2, IL-6, TNF-\u3b1, CXCL2, and MCP1 mRNA, were observed in both cell types. Co-culture of THP-1 macrophages with HepG2 overexpressing hPCSK9 also showed the induction of TNF-\u3b1 (2.4\u2009\ub1\u20090.5 fold) and IL-1\u3b2 (8.6\u2009\ub1\u20091.8 fold) mRNA in macrophages. The effect of hPCSK9 on TNF-\u3b1 mRNA in murine LDLR-/- bone marrow macrophages (BMM) was significantly impaired as compared to wild-type BMM (4.3\u2009\ub1\u20091.6 fold vs 31.1\u2009\ub1\u20096.1 fold for LDLR-/- and LDLR+/+, respectively). Finally, a positive correlation between PCSK9 and TNF-\u3b1 plasma levels of healthy adult subjects (males 533, females 537) was observed (B\u2009=\u20098.73, 95%CI 7.54\u2009\uf7\u20099.93, p\u2009<\u20090.001). Taken together, the present study provides evidence of a pro-inflammatory action of PCSK9 on macrophages, mainly dependent by the LDLR

A Lumped Parameter Model to Study Atrioventricular Valve Regurgitation in Stage 1 and Changes Across Stage 2 Surgery in Single Ventricle Patients

Goal: This manuscript evaluates atrioventricular valve regurgitation (AVVR) in babies born with an already very challenging heart condition, i.e. with single ventricle physiology. Although the second surgery that single ventricle patients undergo is thought to decrease AVVR, there is much controversy in the clinical literature about AVVR treatment. Methods: The effect of atrioventricular valve regurgitation (AVVR) on Stage 1 haemodynamics and resulting acute changes from conversion to Stage 2 circulation in single ventricle patients are analysed through lumped parameter models. Several degrees of AVVR severity are analysed, for two types of valve regurgitation: incomplete leaflet closure and valve prolapse. Results: The models show that increasing AVVR in Stage 1 induces the following effects: i) higher stroke volume and associated decrease in ventricular end-systolic volume; ii) increase in atrial volumes with V-loop enlargement in pressure-volume curves; iii) pulmonary venous hypertension. The Stage 2 surgery results in volume unloading of the ventricle thereby driving a decrease in AVVR. However, this effect is offset by an increase in ventricular pressures resulting in a net increase in regurgitation fraction (RF) of approximately 0.1 (for example, in severe AVVR, the pre-operative RF increases from ~60% to ~70% post-operatively). Moreover, despite some improvements to sarcomere function early after Stage 2 surgery, it may deteriorate in cases of severe AVVR. Conclusion: In patients with moderate to severe AVVR, restoration of atrioventricular valve competence prior to, or at the time of, Stage 2 surgery would likely lead to improved haemodynamics and clinical outcome as the models suggest that uncorrected AVVR can worsen across Stage 2 surgery. This was found to be independent of the AVVR degree and mechanisms

miniaturized fish for screening of onco hematological malignancies

Fluorescence in situ hybridization (FISH) represents a major step in the analysis of chromosomal aberrations in cancer. It allows the precise detection of specific rearrangements, both for diagnost..

Monomeric gremlin is a novel vascular endothelial growth factor receptor-2 antagonist

Angiogenesis plays a key role in various physiological and pathological conditions, including inflammation and tumor growth. The bone morphogenetic protein (BMP) antagonist gremlin has been identified as a novel pro-angiogenic factor. Gremlin promotes neovascular responses via a BMP-independent activation of the vascular endothelial growth factor (VEGF) receptor-2 (VEGFR2). BMP antagonists may act as covalent or non-covalent homodimers or in a monomeric form, while VEGFRs ligands are usually dimeric. However, the oligomeric state of gremlin and its role in modulating the biological activity of the protein remain to be elucidated.Here we show that gremlin is expressed in vitro and in vivo both as a monomer and as a covalently linked homodimer. Mutagenesis of amino acid residue Cys141 prevents gremlin dimerization leading to the formation of gremlinC141A monomers. GremlinC141A monomer retains a BMP antagonist activity similar to the wild-type dimer, but is devoid of a significant angiogenic capacity. Notably, we found that gremlinC141A mutant engages VEGFR2 in a non-productive manner, thus acting as receptor antagonist. Accordingly, both gremlinC141A and wild-type monomers inhibit angiogenesis driven by dimeric gremlin or VEGF-A165. Moreover, by acting as a VEGFR2 antagonist, gremlinC141A inhibits the angiogenic and tumorigenic potential of murine breast and prostate cancer cells in vivo.In conclusion, our data show that gremlin exists in multiple forms endowed with specific bioactivities and provide new insights into the molecular bases of gremlin dimerization. Furthermore, we propose gremlin monomer as a new inhibitor of VEGFR2 signalling during tumor growth