0128 : Sca-1 positive cells, but not c-kit positive cells, differentiate into mature cardiomyocytes after brain natriuretic peptide treatment

The Brain Natriuretic Peptide (BNP) is a cardiac hormone, which promotes the recovery of cardiac function and the preservation of cardiac tissue in animal models of heart diseases. Its cardiac protective role in animals was attributed to fibrosis inhibition, as well as to reduction of cardiomyocyte apoptosis and hypertrophy. Recently, we demonstrated that BNP induces heart regeneration via the stimulation of cardiac precursor cell (CPC) proliferation and differentiation into mature cardiomyocytes.The aim of our study was to identify which CPC’s subset is able to respond to BNP stimulation.Cardiac precursor cells identified as being Sca-1+ Nkx2.5+ or c-kit+ Nkx2.5+ cells, expressed in neonatal and adult hearts BNP’s receptors (NPR-A and NPR-B), showing their ability to be activated by BNP treatment. Cell sorting experiments based on the expression of Sca-1 or c-kit were performed on nonmyocyte cells isolated from neonatal wild-type hearts. Sca-1+ and c-kit+ cells were cultured up to 3 weeks with or without BNP in differentiating medium. Sca-1 positive cells, which contained few c-kit+ cells, responded clearly to BNP stimulation by upregulating mRNA levels of genes coding for Nkx2.5, Mlc-2v, c-kit, Sca-1, beta and alpha MHC. Furthermore, higher number of Troponin I+ cells was detected in BNP treated cells compared to untreated cells, suggesting that Sca-1+ cells differentiated after BNP stimulation into mature cardiomyocytes. BNP treatment of c-kit+ cells didn’t induce the upregulation of mRNA coding for cardiomyocyte specific genes. However, we determined that c-kit positive cells spontaneously differentiated into mature cardiomyocytes during the 3 weeks of cell culture without BNP stimulation.To determine which receptor is involved, Sca-1+ cells, isolated from neonatal hearts of NPR-A or NPR-B deficient mice, were treated with BNP. The effects of BNP on wild type and NPR-A KO cells did not differ substantially. However, Sca-1+ cells isolated from NPR-B deficient hearts couldn’t respond anymore to BNP stimulation.Thus, BNP specifically stimulates via NPR-B Sca-1+ cell differentiation into cardiomyocytes. c-kit+ cells display clearly a cardiogenic potential which is BNP independent

The long way to bilingualism: the peculiar case of multilingual South Tyrol

In the present contribution we discuss the challenges and the results of learning a second language in South Tyrol, the multilingual border region in northern Italy where the autochthonous German- and Ladinspeaking communities have cohabited with the Italian-speaking community since the end of the First World War. The picture resulting from the data collected in the Kolipsi project (Eurac/DiScoF), an extensive linguistic and psychosocial investigation about South Tyrolean secondary school pupils now in its second edition, gives precious inputs to all entities that intervene in the process of attitude formation and change, ranging from the family environment to politics.En el presente trabajo, debatimos los retos y los resultados del proceso de aprendizaje de segundas lenguas en el Tirol del Sur, la región fronteriza multilingüe del norte de Italia donde las comunidades autóctonas hablantes de alemán y ladino han convivido con la comunidad italohablante desde el fin de la Primera Guerra Mundial. La imagen resultante de los datos recogidos en el proyecto Kolipsi (Eurac/DiScoF), una investigación abarcadora tanto lingüística como psicosocial sobre alumnado de secundaria del Tirol del Sur, proporciona información muy valiosa a todas las entidades que intervienen en el proceso de la formación y el cambio de las actitudes, desde el entorno familiar hasta el ámbito de la política

0232: A new role of the brain natriuretic peptide in the heart: Modulation of cardiac precursor cell proliferation and differentiation

The actual role of the brain natriuretic peptide (BNP) in the heart remains elusive despite its reported protective effect in ischemic animal hearts. Because recently BNP was shown to control the proliferation and differentiation of murine embryonic stem cells, we asked in this study whether BNP could influence the proliferation and differentiation of cardiac progenitor cells (CPC) in vitro and in vivo. We first identified a c-kit+ Sca-1+ cell population present in neonatal and adult hearts which expressed the NPR-A and NPR-B receptors. In vitro, these cells proliferated and in presence of BNP differentiated into CPCs (c-kit+ Sca-1+ Nkx2.5+) and into mature cardiomyocytes. In parallel, BNP was injected to newborn and adult healthy mice (n=6 mice per group). In the hearts of both neonatal and adult mice, BNP injection increased the number of newly formed cardiomyocytes (neonatal: + 23%, p= 0.009 and adult: +68%, p= 0.005) and the number of CPCs (neonatal: + 142%, p= 0.002 and adult: +134%, p= 0.04). BrdU injection to neonatal BNP treated mice demonstrated that BNP stimulated CPC proliferation. In anticipation that BNP might be used as a therapeutic agent, we injected BNP into mice undergoing myocardial infarction (n=6-7 mice per group). Higher numbers of Nkx2.5+ cells were detected in both the infarcted (+38%, p=0.03) and non infarcted areas (+69%, p=0.02) of BNP treated hearts one week after surgery. Finally, by isolating neonatal cardiac cells from the hearts of NPR-A or NPR-B deficient mice, we demonstrated that BNP modulates the fate of CPCs via NPRB binding and that long term BNP treatment is correlated in vitro and in vivo with decreased Protein Kinase G activity. Our results highlight a new key role for BNP in the control of CPC proliferation and/or differentiation. This new function of BNP should be evaluated in therapies aimed to induce cardiac cell regeneration and should reopen the debate about the therapeutic use of BNP for patients suffering from heart diseases

Peroxynitrite induces HMGB1 release by cardiac cells in vitro and HMGB1 upregulation in the infarcted myocardium in vivo

Aims High-mobility group box 1 (HMGB1) is a nuclear protein actively secreted by immune cells and passively released by necrotic cells that initiates pro-inflammatory signalling through binding to the receptor for advance glycation end-products. HMGB1 has been established as a key inflammatory mediator during myocardial infarction, but the proximal mechanisms responsible for myocardial HMGB1 expression and release in this setting remain unclear. Here, we investigated the possible involvement of peroxynitrite, a potent cytotoxic oxidant formed during myocardial infarction, on these processes. Methods and results The ability of peroxynitrite to induce necrosis and HMGB1 release in vitro was evaluated in H9c2 cardiomyoblasts and in primary murine cardiac cells (myocytes and non-myocytes). In vivo, myocardial HMGB1 expression and nitrotyrosine content (a marker of peroxynitrite generation) were determined following myocardial ischaemia and reperfusion in rats, whereas peroxynitrite formation was inhibited by two different peroxynitrite decomposition catalysts: 5,10,15,20-tetrakis(4-sulphonatophenyl) porphyrinato iron (III) (FeTPPS) or Mn(III)-tetrakis(4-benzoic acid) porphyrin chloride (MnTBAP). In all types of cells studied, peroxynitrite (100 μM) elicited significant necrosis, the loss of intracellular HMGB1, and its passive release into the medium. In vivo, myocardial ischaemia-reperfusion induced significant myocardial necrosis, cardiac nitrotyrosine formation, and marked overexpression of myocardial HMGB1. FeTPPS reduced nitrotyrosine, decreased infarct size, and suppressed HMGB1 overexpression, an effect that was similarly obtained with MnTBAP. Conclusion These findings indicate that peroxynitrite represents a key mediator of HMGB1 overexpression and release by cardiac cells and provide a novel mechanism linking myocardial oxidative/nitrosative stress with post-infarction myocardial inflammatio

Uniformity in the Wiener-Wintner theorem for nilsequences

We prove a uniform extension of the Wiener-Wintner theorem for nilsequences due to Host and Kra and a nilsequence extension of the topological Wiener-Wintner theorem due to Assani. Our argument is based on (vertical) Fourier analysis and a Sobolev embedding theorem.Comment: v3: 18 p., proof that the cube construction produces compact homogeneous spaces added, measurability issues in the proof of Theorem 1.5 addressed. We thank the anonymous referees for pointing out these gaps in v

Bacterial flagellin elicits widespread innate immune defense mechanisms, apoptotic signaling, and a sepsis-like systemic inflammatory response in mice

Introduction: Systemic inflammation in sepsis is initiated by interactions between pathogen molecular motifs and specific host receptors, especially toll-like receptors (TLRs). Flagellin is the main flagellar protein of motile microorganisms and is the ligand of TLR5. The distribution of TLR5 and the actions of flagellin at the systemic level have not been established. Therefore, we determined TLR5 expression and the ability of flagellin to trigger prototypical innate immune responses and apoptosis in major organs from mice. Methods: Male Balb/C mice (n = 80) were injected intravenously with 1-5 mu g recombinant Salmonella flagellin. Plasma and organ samples were obtained after 0.5 to 6 h, for molecular investigations. The expression of TLR5, the activation state of nuclear factor kappa B (NF kappa B) and mitogen-activated protein kinases (MAPKs) [extracellular related kinase (ERK) and c-jun-NH2 terminal kinase (JNK)], the production of cytokines [tumor necrosis alpha (TNF alpha), interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), macrophage inhibitory protein-2 (MIP-2) and soluble triggering receptor expressed on myeloid cells (TREM-1)], and the apoptotic cleavage of caspase-3 and its substrate Poly(ADP-ribose) polymerase (PARP) were determined in lung, liver, gut and kidney at different time-points. The time-course of plasma cytokines was evaluated up to 6 h after flagellin. Results: TLR5 mRNA and protein were constitutively expressed in all organs. In these organs, flagellin elicited a robust activation of NF kappa B and MAPKs, and induced significant production of the different cytokines evaluated, with slight interorgan variations. Plasma TNF alpha, IL-6 and MIP-2 disclosed a transient peak, whereas IL-1 beta and soluble TREM-1 steadily increased over 6 h. Flagellin also triggered a marked cleavage of caspase-3 and PARP in the intestine, pointing to its ability to promote significant apoptosis in this organ. Conclusions: Bacterial flagellin elicits prototypical innate immune responses in mice, leading to the release of multiple pro-inflammatory cytokines in the lung, small intestine, liver and kidney, and also activates apoptotic signalling in the gut. Therefore, this bacterial protein may represent a critical mediator of systemic inflammation and intestinal barrier failure in sepsis due to flagellated micro-organism

Bacterial Flagellin Triggers Cardiac Innate Immune Responses and Acute Contractile Dysfunction

BACKGROUND: Myocardial contractile failure in septic shock may develop following direct interactions, within the heart itself, between molecular motifs released by pathogens and their specific receptors, notably those belonging to the toll-like receptor (TLR) family. Here, we determined the ability of bacterial flagellin, the ligand of mammalian TLR5, to trigger myocardial inflammation and contractile dysfunction. METHODOLOGY/PRINCIPAL FINDINGS: TLR5 expression was determined in H9c2 cardiac myoblasts, in primary rat cardiomyocytes, and in whole heart extracts from rodents and humans. The ability of flagellin to activate pro-inflammatory signaling pathways (NF-kappaB and MAP kinases) and the expression of inflammatory cytokines was investigated in H9c2 cells, and, in part, in primary cardiomyocytes, as well as in the mouse myocardium in vivo. The influence of flagellin on left ventricular function was evaluated in mice by a conductance pressure-volume catheter. Cardiomyocytes and intact myocardium disclosed significant TLR5 expression. In vitro, flagellin activated NF-kappaB, MAP kinases, and the transcription of inflammatory genes. In vivo, flagellin induced cardiac activation of NF-kappaB, expression of inflammatory cytokines (TNF alpha, IL-1 beta, IL-6, MIP-2 and MCP-1), and provoked a state of reversible myocardial dysfunction, characterized by cardiac dilation, reduced ejection fraction, and decreased end-systolic elastance. CONCLUSION/SIGNIFICANCE: These results are the first to indicate that flagellin has the ability to trigger cardiac innate immune responses and to acutely depress myocardial contractility

Epidermal growth factor suppresses intestinal epithelial cell shedding both in vitro and in vivo via a MAPK dependent pathway

Cell shedding from the intestinal villus is a key element of tissue turnover, essential to maintain health and homeostasis. However, the signals regulating this process are not well understood. We asked whether shedding is controlled by epidermal growth factor receptor (EGFR), an important driver of intestinal growth and differentiation. In 3D ileal enteroid culture and cell culture models (MDCK, IEC-6, IPEC-J2 cells), extrusion events were suppressed by EGF, as determined by direct counting of released cells or rhodamine-phalloidin labeling of condensed actin rings. Blockade of MEK/ERK, but not other downstream pathways such as PI3K or PKC, reversed EGF inhibition of shedding. These effects were not due to a change in cell viability. Furthermore, EGF-driven MAPK signaling inhibited both caspase-independent and -dependent shedding pathways. Similar results were found in vivo, in a novel zebrafish model for intestinal epithelial shedding. Together, the data show that EGF suppresses cell shedding in the intestinal epithelium through a selective, MAPK dependent pathway affecting multiple extrusion mechanisms. EGFR signaling may be a therapeutic target for disorders featuring excessive cell turnover, such as inflammatory bowel diseases

Augmenting Autologous Stem Cell Transplantation to Improve Outcomes in Myeloma

Consolidation with high-dose chemotherapy and autologous stem cell transplantation (ASCT) is the standard of care for transplantation-eligible patients with multiple myeloma, based on randomized trials showing improved progression-free survival with autologous transplantation after combination chemotherapy induction. These trials were performed before novel agents were introduced; subsequently, combinations of immunomodulatory drugs and proteasome inhibitors as induction therapy have significantly improved rates and depth of response. Ongoing randomized trials are testing whether conventional autologous transplantation continues to improve responses after novel agent induction. Although these results are awaited, it is important to review strategies for improving outcomes after ASCT. Conditioning before ASCT with higher doses of melphalan and combinations of melphalan with other agents, including radiopharmaceuticals, has been explored. Tandem ASCT, consolidation, and maintenance therapy after ASCT have been investigated in phase III trials. Experimental cellular therapies using ex vivo–primed dendritic cells, ex vivo–expanded autologous lymphocytes, Killer Immunoglobulin Receptor (KIR)-mismatched allogeneic natural killer cells, and genetically modified T cells to augment ASCT are also in phase I trials. This review summarizes these strategies and highlights the importance of exploring strategies to augment ASCT, even in the era of novel agent induction

A rapid synthesis of the evidence on interventions supporting self-management for people with long-term conditions. (PRISMS Practical systematic RevIew of Self-Management Support for long-term conditions)

Background: Despite robust evidence concerning self-management for some long-term conditions (LTCs), others lack research explicitly on self-management and, consequently, some patient groups may be overlooked. Aim: To undertake a rapid, systematic overview of the evidence on self-management support for LTCs to inform health-care commissioners and providers about what works, for whom, and in what contexts. Methods: Self-management is ‘the tasks . . . individuals must undertake to live with one or more chronic conditions . . . [including] . . . having the confidence to deal with medical management, role management and emotional management of their conditions’. We convened an expert workshop and identified characteristics of LTCs potentially of relevance to self-management and 14 diverse exemplar LTCs (stroke, asthma, type 2 diabetes mellitus, depression, chronic obstructive pulmonary disease, chronic kidney disease, dementia, epilepsy, hypertension, inflammatory arthropathies, irritable bowel syndrome, low back pain, progressive neurological disorders and type 1 diabetes mellitus). For each LTC we conducted systematic overviews of systematic reviews of randomised controlled trials (RCTs) of self-management support interventions (‘quantitative meta-reviews’); and systematic overviews of systematic reviews of qualitative studies of patients’ experiences relating to self-management (‘qualitative meta-reviews’). We also conducted an original systematic review of implementation studies of self-management support in the LTCs. We synthesised all our data considering the different characteristics of LTCs. In parallel, we developed a taxonomy of the potential components of self-management support. Results: We included 30 qualitative systematic reviews (including 515 unique studies), 102 quantitative systematic reviews (including 969 RCTs), and 61 studies in the implementation systematic review. Effective self-management support interventions are multifaceted, should be tailored to the individual, their culture and beliefs, a specific LTC and position on the disease trajectory, and underpinned by a collaborative/communicative relationship between the patient and health-care professional (HCP) within the context of a health-care organisation that actively promotes self-management. Self-management support is a complex intervention and although many components were described and trialled in the studies no single component stood out as more important than any other. Core components include (1) provision of education about the LTC, recognising the importance of understanding patients’ pre-existing knowledge and beliefs about their LTC; (2) psychological strategies to support adjustment to life with a LTC; (3) strategies specifically to support adherence to treatments; (4) practical support tailored to the specific LTC, including support around activities of daily living for disabling conditions, action plans in conditions subject to marked exacerbations, intensive disease-specific training to enable self-management of specific clinical tasks; and (5) social support as appropriate. Implementation requires a whole-systems approach which intervenes at the level of the patient, the HCP and the organisation. The health-care organisation is responsible for providing the means (both training and time/material resources) to enable HCPs to implement, and patients to benefit from, self-management support, regularly evaluating self-management processes and clinical outcomes. More widely there is a societal need to address public understanding of LTCs. The lack of public story for many conditions impacted on patient help-seeking behaviour and public perceptions of need. Conclusions: Supporting self-management is inseparable from the high-quality care for LTCs. Commissioners and health-care providers should promote a culture of actively supporting self-management as a normal, expected, monitored and rewarded aspect of care. Further research is needed to understand how health service managers and staff can achieve this culture change in their health-care organisations. Study registration: This study is registered as PROSPERO CRD42012002898. Funding: The National Institute for Health Research Health Services and Delivery Research programme