Objetivos: Comparar as distribuições das medidas dos instrumentos DUFS, DEFS e Pictograma de Fadiga de acordo com a gravidade da insuficiência cardíaca (IC) avaliada pela Classe Funcional da New York Heart Association (CF-NYHA) e a avaliar sua relação com a fração de ejeção do ventrículo esquerdo (FEVE). Método: Estudo metodológico, de corte transversal, cuja amostra foi composta por adultos com IC atendidos em um hospital universitário do Estado de São Paulo, de setembro de 2014 a março de 2015. O DUFS avalia a fadiga relacionada à cardiopatia (8 itens, intervalo total de 8 a 40; quanto maior o valor, maior a intensidade da fadiga) e o DEFS avalia a fadiga relacionada às atividades físicas e aos esforços (9 itens, intervalo de nove a 45; maiores valores indicando maior intensidade da fadiga). O Pictograma de Fadiga avalia a intensidade (item A) e o impacto (item B) da fadiga relacionada às atividades da vida diária, quanto maior a pontuação em cada item, maior a sensação e o impacto da fadiga. Os dados foram coletados por entrevistas e consulta aos prontuários. Para testar se as médias dos grupos eram diferentes, fizemos uma Análise de Variância com o valor da escala como variável resposta e CF-NYHA grupo como variável explanatória. Quando o fator grupo era estatisticamente significante, fizemos o teste de comparação múltipla de médias (método post hoc de Bonferroni). Para verificar a correlação entre as medidas obtidas pelos instrumentos DUFS e DEFS e a FEVE, foi utilizado o teste de Correlação de Pearson. A associação entre as distribuições das respostas aos itens do Pictograma de Fadiga e a FEVE, categorizada em preservada (>= 55) ou reduzida (<55), foi analisada pelo teste Exato de Fisher. O nível de significância adotado foi de 0,05. Resultados: Participaram 118 pacientes, com média de idade de 63 (D.P.=13) anos, 62% do sexo masculino, 86% não desempenhavam atividades remuneradas, com média de 6 (D.P.=5) anos de estudo. Observamos aumento nas médias das medidas obtidas por DUFS ou DEFS entre os pacientes de acordo com a progressão da doença medida pela CF-NYHA (p<0,001, para os dois instrumentos). Não constatamos diferenças entre a fadiga (avaliada pelo DUFS) dos pacientes da CF-NYHA III com os das II e IV. Ao analisarmos as diferenças da fadiga, avaliada pelo DEFS, não observamos diferenças entre as médias dos pacientes da CF-NYHA II com os das I e III, e os da III, com os pacientes da IV. As correlações entre a FEVE com as medidas de fadiga foram de positiva e fraca magnitude para o DEFS (r=0,18; p=0,05) e para o DUFS (r=0,16; p=0,08). Somente o item A do Pictograma de Fadiga teve associação com os grupos de CF-NYHA (p<0,001). Conclusão: Os três instrumentos demonstraram piora nos níveis de fadiga de acordo com a gravidade da doença avaliada pela CF-NYHA, entretanto, não houve discriminação entre os grupos de maior gravidade, pois houve grande variação dentro de cada grupo funcional / Objectives: Compare the distributions of the measures of the Dutch Fatigue Scale (DUFS), Dutch Exertion Fatigue Scale (DEFS) and Fatigue Pictogram according to the severity of heart failure (HF), assessed by the New York Heart Association Functional Class (NYHA-FC) and to assess its relationship with the left ventricle ejection fraction (LVEF). Method: Methodological, cross-sectional study with a sample composed of adults with HF cared for by a university hospital in the state of São Paulo, Brazil from September 2014 to March 2015. The DUFS assesses fatigue related to heart disease (8 items, total interval from 8 to 40; the higher the score, the more intense the fatigue) and the DEFS assesses fatigue related to physical exertion (9 items, interval from nine to 45; higher scores indicate more intense fatigue). The Fatigue Pictogram assesses the intensity (item A) and impact (item B) of fatigue related to daily living activities; the higher each item\"s score, the greater the intensity and impact of fatigue. Data were collected using interviews and by consulting medical files. To test whether the groups\" means were different, an analysis of variance was performed with the scale\"s score as the response variable and the group\"s FC-NYHA as the explanatory variable. When the group factor was statistically significant, a multiple comparison test (Bonferroni\"s post-hoc method) was used. Person\"s Correlation test was used to verify correlation between the measures obtained by the DUFS, DEFS and LVFE. Association between the distributions of responses to the Fatigue Pictogram\"s items and LVEF, categorized in preserved (>= 55) or reduced (<55), was analyzed by the Fisher\"s exact test. The level of significance adopted was 0.05. Results: A total of 118 patients aged 63 (SD=13) years old on average participated; 62% were males, 86% did not have a paid job, with 6 (SD=5) years of education, on average. The means of the measures obtained by the DUFS or DEFS increased among patients as the disease progressed, as measure by the NYHA-FC (p<0.001 for both instruments). No differences were found between the fatigue (assessed by the DUFS) of patients classified in NYHA-FC III with those classified in NYHA-FC II and IV. When analyzing means of fatigue, measured by the DEFS, no differences were found between the means of patients in NYHA-FC II with those in functional classes I or III, or between those in NYHA-FC III with patients in IV. Correlations between LVEF and fatigue measures were of a positive and weak magnitude for the DEFS (r=0.18; p=0.05) and for the DUFS (r=0.16; p=0.08). Only item A of the Fatigue Pictogram was associated with NYHA- FC groups (p<0.001). Conclusion: The three instruments showed worse levels of fatigue according to the severity of the disease assessed by NYHA-FC, however, there was no discrimination between the groups with greater severity, as there was a large variation within each functional group

A redução do consumo de alimentos é freqüente durante a descompensação da insuficiência cardíaca, quando há um aumento do gasto energético basal. Os triglicérides de cadeia média, utilizados como suplementação energética, aumentam a densidade calórica dos alimentos, contribuindo para o metabolismo energético dos pacientes com insuficiência cardíaca. O objetivo foi avaliar o efeito da suplementação de triglicérides de cadeia média sobre o quoeficiente respiratório, na insuficiência cardíaca congestiva e na baixa ingestão alimentar. Foi realizado um estudo randomizado aberto com 45 pacientes de 18 a 70 anos com insuficiência cardíaca congestiva descompensada, fração de ejeção < 0,45, sem drogas vasoativas, dieta oral, IMC < 25kg/m2 para adultos e < 27 kg/m2 para idosos. Foram alocados aleatoriamente para grupo com suplementação de TCM e grupo controle. Os grupos realizaram duas medidas de VCO2 e VO2, por calorimetria indireta. O QR foi avaliado pela análise de variância com medidas repetidas. Foi considerado significante P < 0,05. 75% dos pacientes foram identificados em eutrofia pelo IMC, porém destes, 67% foram diagnosticados com desnutrição calórica e 65% com desnutrição protéico calórica quando analisados e classificados os indicadores de dobras cutâneas. A proporção de lipídeos aumentou de 9,5% para 57% das recomendações com 236,7 ± 95,0 kcal/d do triglicérides de cadeia média (P <0,001). A ingestão de calorias aumentou de 1966,3 ± 643,3 kcal /d para 2202,7 ± 708,4 kcal /d no grupo intervenção e manteve 1960,7 ± 702,6 kcal /d no grupo controle. Não houve variação significativa quoeficiente respiratório (grupo triglicérides de cadeia média +0,4%; grupo controle: +2,5%, P = 0,458). Quatro pacientes apresentaram efeitos adversos ao suplemento, no entanto, sem necessidade de suspensão. O triglicéride de cadeia média não reduziu o quoeficiente respiratório, no entanto melhorou a proporção de carboidratos e lipídios, contribuindo para a melhora do aproveitamento energético. / Food intake reduction is frequent during decompensation of heart failure, when basal energy expenditure increases. In addition, medium chain triglycerides are used as energy supplementation increases caloric density of food, contributing to energy metabolism of patients with heart failure. The objective was to evaluate the effect of supplementation of medium chain triglycerides on the respiratory coefficient in congestive heart failure and low food intake. We conducted a randomized open label study with 45 patients from 18 to 70 years old with decompensated congestive heart failure, ejection fraction < 0,45, without intravenous inotropic drugs, oral diet and body mass index < 25 kg/m2 for adults and <27 kg/m2 for the elderly Patients were randomly allocated to supplementation with medium chain triglycerides or control group. They were submitted to two measurements of VCO2 and VO2 by indirect calorimetry. Analysis of variance with repeated measures analyzes respiratory coefficient change and two-sided. P< 0,05 was significant. 75% of patients were identified in eutrophic by body mass index, but these, 67% were diagnosed with calorie malnutrition and 65% with protein calorie malnutrition when analyzed and classified by skinfolds measures. Adequate proportion of carbohydrates and lipids increased from 9,5% to 57% of patients with 236,7 ± 95,0 kcal/d of medium chain triglycerides (P<0,001). Caloric intake increased from 1966,3 ± 643,3 kcal/d to 2202,7 ± 708,4 kcal/d in the medium chain triglycerides group and remained 1960,7 ± 702,6 kcal/d in control group. There was not a significant respiratory coefficient variation (medium chain triglycerides group +0,4%; control group: +2,5%; P=0,458). Four patients presented adverse effects with medium chain triglycerides; however, without requirement of withdrawal. Medium chain triglycerides did not reduce respiratory coefficient, however they improved carbohydrates and lipids proportion, contributing to improvement of energy utilization.

O objetivo desta tese é avaliar a expressão do miRNA-423-5p, em diferentes sítios, em modelo experimental de remodelamento cardíaco após insulto isquêmico em ratos. Os animais foram randomizados em grupos SHAM (cirurgia sem oclusão da artéria coronária descendente anterior esquerda) ou IAM (cirurgia com ligadura da artéria coronária descendente anterior esquerda) e acompanhados por 1, 7, 28 e 90 dias. Após o tempo de seguimento, os animais foram submetidos ao ecocardiograma e eutanasiados. Foi retirado sangue do plexo retroorbital, sangue venoso e arterial e coletado tecido do músculo gastrocnêmio e do ventrículo esquerdo separando as áreas remota (REM), infartada (INF) e peri-infartada (PERI). A partir da homogeneização dos tecidos, foi realizada a extração de miRNA e sua expressão quantificada pelo método de PCR em tempo real. Também foi mensurado os níveis plasmáticos do peptídeo natriurético cerebral (BNP). Os dados foram analisados pela teste de ANOVA de uma e duas vias e correlações através do programa estatístico SPSS 21.0. Quanto a caracterização do modelo utilizado, podemos verificar que a fração de ejeção do ventrículo esquerdo dos ratos IAM foram menores que os do grupo SHAM e os percentuais de área acinética foram iguais em todos os grupos IAM, como esperado. Também observamos que o miRNA-423-5p é expresso no coração, nos diferentes segmentos analisados, apresentando variação significativa nos tempos avaliados, correlacionado-se positivamente com o tamanho do infarto e negativamente com a fração de ejeção do ventrículo esquerdo. Diante deste cenário, nossos achados solidificam o conceito de que a expressão do miRNA-423-p se altera ao longo do tempo após insulto isquêmico e pode ter papel relevante no remodelamento cardíaco de origem isquêmica. / The objective of this project was to evaluate the expression of miRNA-423-5p in an experimental model of cardiac remodeling after ischemic injury in rats. Animals were randomized to SHAM group (surgery without occlusion of the left anterior descending coronary artery) or acute myocardial infaction (AMI) group (surgery with ligation of the left anterior descending coronary artery) and followed for 1, 7, 28 and 90 days. After the follow-up period, the animals were submitted to echocardiography and euthanized. Blood from the retroorbital plexus, venous and arterial blood was collected; and gastrocnemius and left ventricle tissue was collected, separating the remote (REM), infarcted (INF) and peri-infarcted (PERI) areas. From the homogenization of tissues, miRNA was extracted and its expression quantified by real-time PCR. Plasma levels of brain natriuretic peptide (BNP) were also measured by ELISA. Data were analyzed by one-way and two-way ANOVA and coefficient correlations were calculated using the statistical package SPSS 21.0. Regarding the experimental model, we could verify that the left ventricular ejection fraction of the AMI rats were reduced compared to the SHAM group and the percentages of akinetic area were the same in all AMI groups, as expected. We also observed that miRNA-423-5p is expressed in the heart in the different segments analyzed, showing significant variation in the different periodos that were evaluated, is positively correlated with infarct size and negatively with left ventricular ejection fraction. In this scenario, our findings solidify the concept that miRNA-423-p expression changes over time after an ischemic insult and may play a relevant role in the cardiac remodeling of ischemic origin.

Background: The burden of non-communicable diseases including cardiovascular diseases such as heart failure in Africa is rising rapidly, and they are now recognised as a significant cause of morbidity and mortality in the continent. Heart failure causes significant multidimensional impact (physical, social, psychological and spiritual), even with the advent of medicines that offer mortality benefit. Comprehensive care for heart failure must include palliative care that addresses multidimensional needs in line with patient-centered care. However, most research on heart failure in Africa has not explored these multidimensional needs from the patients’ perspective, and palliative care is still seen as being for those with cancer and HIV/AIDS. Aims: To understand the multidimensional experiences, needs, and use of services by patients with heart failure during their disease trajectory. To understand health care professionals’ perceptions of patients’ needs, the care required and the availability of services for patients with advanced heart failure in Uganda. Methods: A total of 48 face to face qualitative longitudinal interviews (36-patient alone, 4 paired-patient and family carer, 8 with bereaved carers), were conducted with 21 patients with stage 3 or 4 heart failure being treated in Mulago Hospital and some of their family carers. Patient interviews were followed by the administration of the African Palliative Care Association African Palliative Outcome Scale supplemented with the broader symptom assessment tool the POS-S. Patients were interviewed during the time of hospitalisation when the researcher first made contact with them, and were followed up monthly by phone. Longitudinal interviews were conducted at 3 and 6 months after the first interview if their clinical condition remained stable, and earlier if there were major concerns or changes in their multidimensional experiences. Eight single interviews were conducted with health professionals (5 doctors, 2 nurses and 1 social worker) involved in the care of the patients. All interviews were audio recorded, and those of the health professionals transcribed verbatim, those of the patients were first translated to English and transcribed and all were exported into QSR Nvivo software version 10 for analysis. Principles from Charmaz’s grounded theory (line by line coding, focused coding, constant comparison and theoretical coding) were employed for analysis. Findings: The patients’ experience was that of learning to live with the unknown in a life dominated by symptoms despite, and because of, treatments. The impact of the various symptoms limited physical performance leading to multiple losses. Presence of a high level of health illiteracy, lack of information on their illness coupled with a high reliance on local cultural beliefs to make health decisions, led to the following: delayed recognition of illness and seeking of care; inappropriate self- care and poor adherence to medications; poor understanding of illness and its prognosis; unrealistic expectations of treatment; and inappropriate choices of where to seek care. Patients were often faced with health system challenges that contributed to late diagnosis and exacerbated the problem of poor adherence to treatment because of lack of medicines and lack of information. The illness impact was also observed in the social, psychological and spiritual domains of patients’ lives causing anxiety and worry, isolation, rejection and stigma, spiritual pain and spiritual growth. Patients expressed the need for normal functioning, information, to be in control and to be facilitated to cope and adapt to the unknown. Patients employed different mechanisms of coping and adaptation, with hope being central in coping as they tried to live with the unknown. Patients suggested changes to the health system and in the conduct of health professionals to improve future care. Health professionals were able to recognise the multidimensional impact of the illness on the patients, but the details of the concerns tended to differ for the patients and health professionals. Health professionals’ proposals on improving care tended to emphasise interventions that would improve physical care as opposed to the other dimensions. Conclusion: This is the first qualitative longitudinal research in Uganda that has explored the experiences of patients with advanced heart failure to gain an understanding of their needs and concerns from their perspective over the course of their illness. Many concerns such as a lack of information, challenges with coping, the symptom experience and its impact on function and the psychological, social and spiritual aspects of their lives are enduring in literature. However, this study also identified other concerns less common in the literature that could have led to a unique illness experience. These included: health system challenges; the impact of culture; beliefs and poverty; and a high level of health illiteracy.

Background: Cardiovascular disease continues to remain a leading cause of morbidity and mortality in both developing and developed worlds. The sirtuin and urocortin systems are novel hormone systems in humans with an emerging role in cardiovascular physiology and pathophysiology. Through a series of studies, this thesis examines the cardiovascular effects of SRT2104 (a novel small molecule SIRT1 activator) in otherwise healthy cigarette smokers and in patients with type 2 diabetes mellitus, and of urocortins 2 and 3 in healthy volunteers and in patients with heart failure. Methods: Twenty-four otherwise healthy cigarette smokers and 15 subjects with stable type 2 diabetes participated in a randomised, double blind, placebo controlled, crossover trial and received 28 days of oral SRT2104 (2.0 g/day) or matched placebo. Plasma SRT2104 concentrations, serum lipid profile, plasma fibrinolytic factors, markers of platelet and monocyte activation and pulse wave analysis and velocity were measured at baseline and the end of each treatment period together with an assessment of forearm blood flow during intra-arterial bradykinin, acetylcholine and sodium nitroprusside infusions. The pharmacodynamic profile of urocortins 2 and 3 were assessed in 18 healthy male volunteers recruited into a series of randomised, double blind, placebo controlled, crossover studies. Bilateral forearm venous occlusion plethysmography was performed during incremental intra-arterial infusions of urocortin 2 (3.6-120 pmol/min), urocortin 3 (1.2-36 nmol/min) and substance P (2-8 pmol/min) in the presence or absence of inhibitors of cyclooxygenase (aspirin), cytochrome P450 metabolites of arachidonic acid (fluconazole) and nitric oxide synthase (L-NG-monomethyl-arginine (L-NMMA)). Finally, 12 patients with stable heart failure (New York Heart Association (NYHA) II-IV) and 10 age- and sex-matched healthy volunteers were recruited to attend once each. Bilateral forearm arterial blood flow was measured using forearm venous occlusion plethysmography during incremental intra-arterial infusions of urocortin 2 (3.6-36 pmol/min), urocortin 3 (360-3600 pmol/min) and substance P (2-8 pmol/min). Results: SRT2104 was safe and well tolerated in otherwise healthy cigarette smokers and subjects with type 2 diabetes mellitus. There were no significant differences in fibrinolytic or blood flow parameters between placebo and SRT2014. Treatment with SRT2104 was associated with a significant reduction in augmentation pressure (P=0.0273) and a trend towards improvement in the augmentation index (AIx) and corrected augmentation index (0.10 > P > 0.05 for both) without significant changes in pulse wave velocity (PWV) and time to wave reflection (Tr) (P > 0.05). Administration of SRT2104 had a favourable effect on lipid profile in otherwise healthy cigarette smokers in comparison to placebo. Urocortins 2 and 3 evoked arterial vasodilatation (P < 0.0001) without tachyphylaxis but with a slow onset and offset of action. Inhibition of nitric oxide synthase with L-NMMA reduced vasodilatation to substance P and urocortin 2 (P≤0.001 for both) but had little effect on urocortin 3 (P > 0.05). Neither aspirin nor fluconazole affected vasodilatation induced by any of the infusions (P > 0.05 for all). In the presence of all three inhibitors, urocortin 2- and urocortin 3-induced vasodilatation were attenuated (P < 0.001 for all) to a greater extent than with L-NMMA alone (P≤0.005). The vasodilatory effects of urocortins 2 and 3 were preserved in patients with heart failure. Conclusion: Activation of SIRT1 through SRT2104 improved lipid profile but did not produce demonstrable differences in vascular or platelet function with some effect on measures of arterial stiffness. Urocortins 2 and 3 appear to be potent arterial vasodilators whose vasomotor responses remained preserved in patients with heart failure and were at least partly mediated via the endothelium. Both hormone systems hold potential in their role in cardiovascular disease in man but require further studies to help translate findings of this thesis to clinical practice.

Identifying people with advanced illnesses whose health is deteriorating, assessing their needs and planning care proactively with them are healthcare priorities given the demographic trend of ageing populations in the UK and internationally. Over the past 10 years (2004-2014), I have led a series of research studies that have made an important academic contribution to improving palliative care services for patients with heart disease and advanced multimorbidity. My first paper reported secondary analysis of data generated from a qualitative study of the illness and care experiences of patients with advanced heart failure. This work used innovative, qualitative research methods to explore and understand patient, carer and health professional perspectives over time. My second study then evaluated whether health and social care services were configured and delivered in response to the needs of people with heart failure and their families. This led me to recommend an anticipatory care framework which integrated a palliative care approach with other aspects of treatment and care. Around this time, advance care planning (planning ahead to facilitate end-of-life care aligned with people’s goals and preferences) was being strongly advocated by NHS health policy makers despite limited research in the UK. For my third study, I evaluated an evidence-based, educational intervention for general practitioners while also exploring barriers and facilitators to advance care planning in primary care for patients with cancer or other advanced conditions. It was becoming increasingly clear that failure to identify people with deteriorating health and a high risk of dying in a timely way was a major barrier to more effective palliative care. The problem was greatest for patients with non-malignant conditions whose illness trajectory is much less easy to predict than in cancer populations. I therefore started to research and develop a new clinical tool designed to prompt early, proactive patient identification in routine clinical practice – the Supportive and Palliative Care Indicators Tool (SPICT). My fourth research paper reported an evaluation of the SPICT in a mixed-methods study in a large tertiary care hospital. The SPICT was then used to identify people with multimorbidity for my fifth study, a longitudinal exploration of patient and carer experiences of hospital admission and ongoing community care. In my final paper, I drew on my previous research and combined this with well-developed approaches to timely identification and effective communication. I described the design of a successful pilot randomised trial of future care planning with people who had advanced heart disease and their carers. This thesis presents a critical review of these six research studies setting them in context and demonstrating the impact they have had in ensuring that high quality research evidence informs current and future developments in palliative care policy and clinical practice.

The development and function of the heart is governed by a conserved set of transcription factors (TFs) that regulate gene expression in a cell-type, time point and stimulus driven manner. Of these core cardiac TFs, the most ubiquitously expressed is the zinc finger protein GATA4. In cardiomyocytes, GATA4 is central to proliferation, differentiation, hypertrophy and induction of pro-survival pathways. In cardiac endothelial cells, it is required for valve and septal development, although the exact mechanisms remain unclear. To regulate such a wide array of functions in a spatially and temporally controlled manner, GATA4 interacts with specific protein partners, the majority of whom have been identified in cardiomyocytes. However, a complete understanding of the protein interactome of GATA4, particularly in cardiac endothelial cells, has not yet been achieved. Using a mass spectrometry-based approach, we have identified a series of novel GATA4 interacting partners in cardiac endothelial cells. 3xFlag GATA4 was stably overexpressed via retroviral transduction in the TC13 cardiac endothelial precursor cell line, immunoprecipitated from nuclear protein extracts and sent for HPLC-ESI-MS/MS. Several novel GATA4 interacting partners were identified including the chaperone protein Heat Shock Protein 70 (HSP70), the inducible orphan nuclear receptor Nerve Growth Factor 1β (NGFIβ, NUR77) and the Drosophila-Binding/Human Splicing protein family members Non-POU Domain Containing Octamer Binding Protein (NONO) and Paraspeckle 1 (PSPC1). Chapter 1 discusses the interaction between GATA4 and HSP70 and its role in cardiomyocyte survival upon exposure to chemotherapeutic agent Doxorubicin (DOX). HSP70 binds directly to GATA4, preventing DOX-mediated cleavage and degradation by Caspase-1, cardiomyocyte cell death and heart failure. Chapter 2 focuses on the cooperative interaction between GATA4 and NUR77 in cardiac microvascular endothelial cells and its central role in myocardial angiogenesis in response to pressure overload. The GATA4-NUR77 complex transactivates the promoter of Angiopoietin-Like 7 (ANGPTL7), a secreted pro-angiogenic chemotactic factor, triggering endothelial cell proliferation and tube formation in cultured cardiac endothelial cells and increasing myocardial capillary density in vivo. Chapter 3 discusses the interaction between GATA4 and the DBHS proteins NONO and PSPC1 in the regulation of cardiac development. These proteins play opposing roles when bound to GATA4 as PSPC1 enhances GATA4 activation of critical cardiac promoter targets and NONO acts as a rheostat to repress GATA4 activity. In vivo, loss of NONO results in left ventricular non-compaction consistent with humans with loss-of-function mutations. However, simultaneous Gata4 haploinsufficiency partially rescues this phenotype. Together, this data identifies multiple novel cell type and time point specific GATA4 protein partners and sheds light on GATA4 regulatory mechanisms in cardiac development and disease.

The pathogenesis of heart failure (HF) involves compensatory left ventricular hypertrophy. Reactive oxygen species (ROS) are elevated in HF and mediate myocardial hypertrophy. ROS also mediate formation of lipid peroxidation byproducts, yet little is known about their role in promoting hypertrophy. One lipid peroxidation byproduct, 4-hydroxy-trans-2-nonenal (HNE) is a reactive aldehyde that forms covalent adducts on proteins. HNE levels are also elevated in HF and may mediate hypertrophy via HNE-adduct formation. LKB1 - a tumor suppressor protein - regulates cellular growth through activation of the downstream kinase AMPK. Activation of AMPK suppresses functions that consume ATP and simultaneously activates processes to generate energy. The LKB1 protein is inhibited by oxidants, but whether this results in myocardial hypertrophy is unclear. I hypothesized that HNE can directly promote cardiac hypertrophy via the modification of LKB1. In HEK293T cells I observed that HNE adducts inhibit activity of LKB1 through direct oxidative modification. Mutation of LKB1 Lys-96 or Lys-97 resulted in less HNE-LKB1 adduct formation. Mutation of LKB1 Lys-97 prevented the inhibitory effect of HNE, suggesting that HNE-adduction at this residue is sufficient to inhibit LKB1. In cardiomyocytes HNE inhibited both LKB1 and AMPK, increased phosphorylation of mTOR, p70S6K, and S6K, and increased protein synthesis. HNE also activated Erk1/2, which contributed to S6K activation but was not required for cellular growth. Hypertrophic S6K activation was dependent on mTOR. Mice fed a high-fat high-sucrose (HFHS) diet have myocardial hypertrophy that can be prevented by antioxidants. Hearts of HFHS mice have HNE-LKB1 adducts, inhibited LKB1 activity, yet no change in AMPK activation. Mice lacking aldehyde dehydrogenase 2 (ALDH2), an enzyme involved in HNE detoxification, have increased myocardial hypertrophy when fed HFHS diet yet have increased LKB1 activity. In summary HNE directly causes hypertrophy in cardiomyocytes. This occurs through inhibition of LKB1 and in part through Erk1/2 activation. In HFHS-fed mice HNE-LKB1 adduct formation is associated with decreased LKB1 activity. Impairing detoxification of reactive aldehydes in the ALDH2-KO mice is sufficient to increase myocardial hypertrophy, but this appears to be independent of LKB1. This study demonstrates a novel mechanism of cardiac hypertrophy caused by reactive aldehydes.

The apelin-apelin receptor (APLNR) system is an important regulator of cardiovascular homeostasis both in health and disease. Principal actions of the apelin-APLNR system are positive inotropism, vasodilatation, diuresis and a potential anti-inflammatory role in vascular tissue. The significance of this system is highlighted in heart failure and pulmonary hypertension. Preclinical models of these diseases report downregulation of apelin- APLNR, whilst knockout strains develop more severe phenotypes, more rapidly. Moreover treatment with exogenous apelin retards or prevents disease progression. In man plasma apelin concentrations are reduced in heart failure and vary with disease severity. Initial increases are reported in mild heart failure suggesting a compensatory role, but are depressed in severe heart failure. Limited data profile myocardial APLNR expression in heart failure and in keeping with plasma apelin concentrations, expression is reduced in severe heart failure. Of interest, the APLNR most closely resembles the angiotensin II type 1 receptor (AT1R), sharing similar tissue expression and sequence homology, but mediates opposing physiological actions. Furthermore, emerging preclinical data support receptor interactions between the APLNR and AT1R that modify their native signalling pathways. It is likely that the apelin-APLNR system serves to antagonise the renin-angiotensin system. Given the established role of angiotensin II, arguably the most important peptide in cardiovascular pathophysiology, any system influencing its actions merits further investigation. Current clinical studies are limited to 20 minutes infusions and understanding its cardiovascular effects requires more prolonged administration. There are concerns of tachyphylaxis and interaction with the renin-angiotensin-aldosterone system (RAAS), possibly reducing efficacy of APLNR agonism in clinical settings. In a series of randomised, blinded crossover clinical trials 60 healthy volunteers and 20 patients with chronic stable heart failure were enrolled to assess the effects of (Pyr1)apelin-13 infusion at rest, during acute and subacute infusion, exercise and upregulation of the renin-angiotensin system. I have identified that APLNR agonism is unaffected by prevailing levels of angiotensin II activity in local vascular beds and systemic haemodynamic infusions. Furthermore, the efficacy of (Pyr1)apelin-13 is retained in healthy volunteers and patients with chronic stable heart failure during acute and subacute infusions. Finally, systemic (Pyr1)apelin-13 does not alter exercise performance in healthy individuals. My findings support a role in targeting the APLNR in chronic heart failure and predict that efficacy will be retained in chronic dosing. Future research directed at other patient groups with ventricular dysfunction is merited, in order to further characterise the utility of this system. These studies are encouraging; however, longer term studies may reveal effects beyond haemodynamic alterations and examine the effects on cardiac fibrosis and endothelial function. A long acting agonist is required to fully evaluate the role of APLNR signalling in cardiovascular disease.

Trata-se de um estudo descritivo correlacional com abordagem quantitativa, que teve como objetivos: caracterizar pacientes com Insuficiência Cardíaca (IC) atendidos em clínica especializada (grupo A) e em pronto-socorro (grupo B), conforme perfil sócio-demográfico, perfil clínico, tempo de conhecimento da doença e internações no último ano; Identificar ações de autocuidado específicas nos grupos A e B; Verificar a diferença entre o autocuidado dos grupos A e B e Identificar os possíveis fatores precipitantes de descompensação no grupo B. A amostra foi constituída por 120 pacientes de um hospital especializado em cardiologia, localizado no município de São Paulo, sendo 60 em cada grupo. A coleta de dados foi realizada de julho a novembro de 2011, por meio da aplicação de instrumento elaborado para o estudo (1) e instrumento de adesão validado em estudo prévio (2). A análise estatística foi descritiva e inferencial, sendo utilizado o Alpha de Cronbach para avaliar a consistência interna do instrumento 2, Teste Exato de Fisher para variáveis categóricas, Teste t-student para comparação entre as médias das variáveis contínuas, teste não paramétrico de Mann-Whitney quando se rejeitou a hipótese de normalidade da variável. Predominou o sexo masculino 78(65%). Não houve diferença no tempo de conhecimento da doença entre os grupos. Observou-se que o grupo B teve mais internações no último ano. Não houve diferença estatisticamente significativa no escore de adesão do Instrumento 2, com média 46,09(±8,03) entre os grupos, para um escore máximo=60. Observou-se pior resultado nas ações de autocuidado referentes à percepção de piora clínica e comunicação com a equipe de saúde; controle de peso e vacinação contra influenza, sem diferença significativa entre os grupos. Identificou-se maior número de idosos, aposentados, sem renda e residindo sozinhos; chagásicos, com piores níveis de uréia, creatinina e hemoglobina e em uso de marcapasso no grupo B. No perfil hemodinâmico do grupo B, verificou-se que 44 (73,4%) pacientes apresentaram sinais de congestão e 37 (61,7%) sinais de baixo débito cardíaco, o que contribuiu para internação prolongada e alta letalidade. Conclui-se que os pacientes realizam parcialmente as ações de autocuidado, devido à dificuldade na percepção e comunicação da piora clínica; controle de peso e vacinação contra influenza, sem diferença significativa entre os grupos. Os possíveis fatores precipitantes de descompensação no grupo B relacionam-se à idade avançada, condições sócio-econômicas e pior perfil clínico. A continuidade deste estudo, com seguimento em seis meses, permitirá identificar os principais desfechos a curto prazo. Sugere-se o acompanhamento de pacientes em ambiente familiar para avaliar a real situação dos cuidados e o desenvolvimento de estudos voltados ao autocuidado de pessoas com IC avançada e/ou de etiologia chagásica, incluindo a criação de programas de cuidados paliativos. / This is a descriptive and correlational study with a quantitative approach, that aimed to characterize patients with heart failure (HF) treated in a Specialty Clinic (Group A) and Emergency Room (Group B), according to socio-demographic and clinical profiles, knowledge time of the disease and hospitalizations in the previous year; Identify specific actions of self-care specifically in Groups A and B; Check the difference between self-care in Groups A and B and identify the possible precipitating factors of decompensation in Group B. The sample consisted of 120 patients in a São Paulo, hospital specialized in cardiology, with 60 patients in each group. Data collection was conducted from July to November 2011, by applying an instrument developed for this study (1) and an instrument of accession validated in a previous study (2). Statistical analysis was descriptive and inferential, by using Cronbach\'s alpha to assess internal consistency of instrument 2, Fisher\'s Exact Test for categorical variables, Student\'s t-test for comparison between means of continuous variables, and non-parametric Mann-Whitney when it rejected the hypothesis of normality of the variable. Seventy-eight (78) males or 65% predominated in this study. There was no difference in the knowledge time of the disease between the groups however it was observed that Group B had more hospitalizations in the past year. There was no statistically significant difference in adherence score of Instrument 2, averaging 46.09 (± 8.03) between the groups, for a maximum score = 60. Worse results were observed in the actions of self-care with reference to the perception of clinical worsening and communication with the health team; weight control and influenza vaccination, without a significant difference between the groups. It was identified that the greater number of elderly, retired, no income and living alone; chagasic patients having worse levels of urea, creatine and hemoglobin and pacemaker use were all in Group B. In the hemodynamic profile of Group B, it was found that 44 (73.4%) patients showed signs of congestion and 37 (61.7%) signs of low cardiac output, contributing to prolonged hospitalization and high mortality. It was concluded that patients perform self-care actions in part because of the difficulty in perception and communication of clinical worsening, weight control and influenza vaccination, without significant difference between the groups. Possible precipitating factors of decompensation in Group B are related to advanced age, socio-economic status and worse clinical profiles. The continuity of this study, with a follow-up in six months, will identify the principal outcomes in the short term. It is suggested that the monitoring of patients be done in a family environment to assess the real situation of care and the development of studies to self-care of people with advanced HF and / or Chagas disease, including the establishment of palliative care programs.