The incidence and mortality from cardiovascular disease (CVD) in patients with chronic kidney disease (CKD) far exceeds that seen in the general population. Whilst a number of risk factors and associations have been identified in patients with CKD that may contribute to the increased risk of CVD, our understanding of the underlying pathophysiology remains poor. It has previously been reported that uraemic animals sustain larger myocardial infarcts and that this ‘reduced ischaemia tolerance’ may in part explain the excess mortality from CVD seen in CKD patients. The aim of this work was to establish an in vivo model of uraemic myocardial infarction in order to further explore the pathophysiology of uraemic CVD with particular focus on ameliorating myocardial ischaemia-reperfusion injury using ischaemic and pharmacological preconditioning. An increase in myocardial infarct size was demonstrated in the sub-total nephrectomy model of chronic uraemia, confirming previous reports in the literature. However, infarct size was not found to be increased in adenine diet induced renal failure. In addition, it was demonstrated for the first time, that the techniques of ischaemic preconditioning (IPC) and remote ischaemic preconditioning (RIPC) are both efficacious and not attenuated by chronic uraemia induced by sub-total nephrectomy or adenine diet (IPC only). Investigations were undertaken using an agent (a HIF stabiliser, FG4497) to induce pharmacological preconditioning in both animals with renal insufficiency and those without. These studies demonstrate that stabilisation of hypoxia inducible factor (HIF) may be a promising strategy to induce pharmacological preconditioning. It is hoped that this work may lay the foundations for future investigations to determine why sub-totally nephrectomised rats have larger infarcts whilst those with adenine induced renal failure, with a substantially greater degree of renal dysfunction, do not. Moreover, it is hoped that; by demonstrating that uraemia 3 does not prevent or attenuate the myocardial protection afforded by ischaemic preconditioning, the recruitment of patients with CKD will be encouraged to clinical trials of both ischaemic preconditioning and other therapies to limit myocardial infarction.

Cardiovascular diseases are responsible for approximately a third of all death worldwide, with hypertension being a major risk factor for many of those. Hypertension can lead to left ventricle hypertrophy and diastolic and systolic dysfunction. Myocardial deformation parameters have been shown to have high sensitivity at the early stage of contractile dysfunction. They can be derived from myocardial tagging, considered to be the goldstandard method, or from routinely acquired cine images using feature tracking (FT) techniques. This work aimed to validate FT as a post processing technique. Three FT software packages were used to measure strain parameters in healthy subjects and hypertensive patients in order to assess agreement. Intra- and inter-observer reproducibility was also investigated. The CVI42 software was found to have the best reproducibility. Good agreement across the three software packages and both groups was also observed for circumferential strain calculated from mid-ventricle short axis and longitudinal strain parameters. CVI42 was also compared to the reference tagging analysis by applying both techniques to a healthy and hypertensive patient cohort. Although tagging could discriminate between the two populations (longitudinal strain), no statistically significant differences were found by CVI42. The final validation step was to generate simulation models mimicking simplified cardiac views to compare the experimental results against a true gold-standard for which strain values are known. Two commercial FT software packages were used to analyze the simulated cine images with increasing complexity levels. Both showed inaccurate tracking and high errors compared to analytical values. This indicated that more realistic and complex numerical models should be investigated. Although FT is a relatively new and promising technique, the results demonstrated that it still requires going through standardization to better understand inter-vendor variability.

Background: Previous studies that have examined functional status in relation to vascular events have focused on the short term after events and have measured functional status a limited number of times. The trajectories of functional status before and after vascular events are not well characterized, and the factors influencing these trajectories are not well known. Methods: A comprehensive, structured, narrative review was performed on the topic of trajectories of disability and cognition surrounding vascular events. Then using 2 large population-based epidemiologic cohorts, the Northern Manhattan Study (NOMAS) and the Cardiovascular Health Study (CHS), trajectories of functional status were examined. In Analysis A, in NOMAS, the effect of inflammatory biomarkers (interleukin-6 [IL6], tumor necrosis factor receptor-1 [TNFR1], C-reactive protein [CRP], and lipoprotein-associated phospholipase-A2 [LpPLA2]) on the intercept and slope of functional status was determined over a median of 13 years, measured with yearly assessments by the Barthel index. In Analysis B, in NOMAS, a similar modeling strategy was used to examine whether subclinical ischemic disease on brain MRIs, measured by subclinical brain infarct (SBI) and white matter hyperintensity volume (WMHV), was associated with functional trajectories. In Analysis C, in CHS, participants had yearly assessments of disability with a combined activities of daily living (ADL) and instrumental ADL scale. The slope of change in disability was compared before and after vascular events (stroke and myocardial infarction [MI]). Results: In Analysis A, CRP (-0.41 BI points per 1 SD increase, 95% CI -0.82 to 0.002) and LpPLA2 (-0.40, 95% CI -0.75 to -0.04) were associated with baseline BI but not change over time. TNFR1 was associated with baseline BI (-0.93, 95% CI -1.59 to -0.26) and change over time (-0.36 BI points per year, 95% CI -0.69 to -0.03). In Analysis B, functional change was -0.85 BI points per year (95%CI -1.01 to -0.69); among those with SBI there were -0.88 additional points annually (-1.44 to -0.32). In WMHV models, annual functional change was -1.04 points (-1.2 to -0.88), with -0.74 additional points annually per SD WMHV increase (-0.99 to -0.49). In Analysis C, stroke (0.88, 95% CI 0.57-1.20, p<0.0001) was associated with a greater acute increase in disability than MI (0.20, 0.06-0.35, p=0.006). The annual increase in disability before stroke (0.06 points per year, 0.002-0.12, p=0.04) more than tripled after stroke (0.15 additional points per year, 0.004-0.30, p=0.04). The annual increase in disability before MI (0.04 points per year, 0.004-0.08, p=0.03) did not change significantly after MI (0.02 additional points per year, -0.07-0.11, p=0.7). Conclusions: In these large population-based studies with repeated measures of functional status and disability over long-term follow-up, several trajectories were found. In Analysis A, TNFR1 predicted worse overall functional status as well as accelerated decline over time. In Analysis B, both SBI and WMHV were associated with accelerated decline. In Analysis C, there was a steeper decline in function after stroke but not MI. These findings help to elucidate the course and potential etiologies of long-term functional decline related to vascular events, and they suggest directions for future research in this area.

Peripheral arterial disease (PAD) affects approximately 200 million individuals worldwide. It is characterized by a reduction in blood flow to the lower extremities due to atherosclerosis. This can result in leg pain, tissue loss, and ultimately amputation. Revascularization procedures aim to restore blood flow, but up to 50% of patients require another intervention within a year. Revascularization monitoring and early detection of failure are crucial in preventing limb loss and adverse cardiovascular events. However, current evaluation methods do not directly measure perfusion and are limited in a significant segment of PAD patients, such as those with diabetes and renal insufficiency. Diffuse optical imaging (DOI) techniques are promising tools to overcome these limitations. Employing near-infrared light, they are non-invasive, non-ionizing, contrast-free, and cost-effective methods that are sensitive to hemodynamic parameters such as changes in oxy-, deoxy-, and total hemoglobin concentration, making DOI ideal for revascularization monitoring. In this dissertation, I investigate and develop DOI systems for the purpose of monitoring lower extremity revascularization procedures in PAD patients. We utilize a contact-based diffuse optical spectroscopy (DOS) system to monitor localized foot perfusion in an ongoing clinical study of 100 patients undergoing lower extremity angiography. I demonstrate the utility of DOS measurements to provide valuable insights into revascularization related hemodynamic remodeling and to predict revascularization success. Furthermore, I also develop a clinic friendly contact-free diffuse optical tomography (DOT) system that is better-suited for PAD patients with ulcers. I show that this system can provide spatial maps of perfusion within the foot. Collectively, this work establishes diffuse optical imaging as a valuable imaging modality for the evaluation of lower extremity perfusion.

Efferocytosis, the clearance of apoptotic cells including apoptotic neutrophils by macrophage phagocytosis, is a key cellular mechanism for resolution of inflammation and tissue repair. Cyclin-dependent kinases (CDKs) 7 and 9 phosphorylate RNA polymerase II that is vital for neutrophil transcriptional capacity. CDK inhibitors such as R-roscovitine, and the more selective inhibitor AT7519, induce neutrophil apoptosis and promote resolution of several mouse models of inflammation including acute lung inflammation. The hypothesis investigated here was that AT7519 would promote neutrophil apoptosis (i) in the infarcted heart, leading to macrophage polarisation, angiogenesis, reduced infarct expansion and retention of cardiac function and (ii) in the peritoneum, enhancing resolution of sterile peritonitis. AT7519 (1μM) induced apoptosis of mouse unstimulated-bone marrow derived neutrophils and thioglycollate-stimulated neutrophils in vitro in a time- and caspase-dependent manner, but did not alter activation assessed by calcium flux in response to the synthetic formyl peptide (fMLF) or platelet-activating factor (PAF). Only high concentrations of AT7519 (10 μM) induced monocyte/macrophage apoptosis and this was likely due to saturated phagocytosis of apoptotic neutrophils induced by high concentration of AT7519. Myocardial infarction (MI) was induced by coronary artery ligation in adult male mice and infarct volume was assessed 7 or 21 days later by in vitro optical projection tomography (OPT). The novel use of OPT for this purpose was validated by demonstrating correlation with infarct volume obtained by late-gadolinium enhanced magnetic resonance imaging in vivo and with infarct area assessed by histological staining (Masson’s Trichrome) in tissue sections. AT7519 (30 mg/kg i.p.) increased the number of apoptotic neutrophils (cleaved caspase-3 and Ly6G +ve) in the heart when administered after MI, but this was not associated with any subsequent alteration in macrophage polarisation, vessel density, infarct expansion or structural and functional remodelling of the left ventricle. In contrast, induction of neutrophil apoptosis by AT7519 (30mg/kg i.p.) successfully promoted macrophage polarisation and the resolution of inflammation associated with peritonitis elicited by either 10% thioglycollate or by 1mg zymosan. AT7519 treatment also reduced the number of CD19+ B cells, Foxp3+CD4+ T cells and eosinophils in peritoneal lavage, and prolonged the phase of monocyte recruitment in zymosan-induced peritonitis. In conclusion, AT7519 successfully induced mouse neutrophil apoptosis in vitro, as well as in vivo in experimental MI and peritonitis. Subsequent promotion of inflammation resolution in peritonitis was not matched by improved outcome following MI. Unexpected effects of CDK inhibition on monocytes, T cells and eosinophils that are necessary for myocardial infarct repair may have compromised any beneficial effects resulting from promotion of in situ neutrophil apoptosis. CDK inhibition may therefore have therapeutic potential for the treatment of peritonitis, but not for prevention of infarct expansion and detrimental ventricular remodelling after MI.

Atherosclerosis is a multifactorial, chronic inflammatory condition characterised by endothelial dysfunction, hyperlipidaemia and the accumulation of fatty deposits within the tunica intima of medium-to-large sized muscular arteries. This disease can prove fatal with patients suffering lethal myocardial infarction or stroke. Recently, two studies investigating the role of G-protein-coupled receptor 55 (GPR55) in atherosclerosis reported conflicting results; one reported a pro-atherogenic role for GPR55 and the other, an anti-atherogenic role for this receptor. Interestingly, another study demonstrated that the activation of GPR55 by lysophosphatidylinositol (LPI) in cultured rat neonatal ventricular cardiomyocytes provokes distinct cellular functions that are dependent on the location of GPR55, leading to suggestions that GPR55 may regulate cardiomyocyte function at two cellular sites and be a potential therapeutic target for cardiac disorders. While it has been demonstrated that GPR55 is important in the maintenance of cardiac function of healthy mice, what is currently unknown is if GPR55 has a role in the cardiovascular remodelling and cardiac function of atherosclerosis prone mice. To address this, the present studies were conducted to investigate 1) the role of GPR55 in atherogenesis, 2) if GPR55 has a role in the cardiac function of mice suffering from atherosclerosis, 3) the signalling pathway by which LPI activates cardiomyocytes, 4) the impact of GPR55 activation on the outcome of myocardial ischaemia/reperfusion (I/R) injury and, 5) the signalling mechanisms by which GPR55 elicits any observed effects on the myocardium in response to such injury. Using C57BL/6 (wildtype; WT), apolipoprotein E knockout (ApoE-/-; mouse model of atherosclerosis), GPR55 knockout (GPR55-/-) and novel ApoE-/-/GPR55-/- mice, this study has established that in the presence of high fat feeding (to accelerate atherosclerosis), GPR55 has a complex role whereby it both regulates risk factors associated with atherosclerosis (i.e. body weight and fat mass) yet promotes the development of fatty streaks within the vasculature, via a lipid independent mechanism. In terms of cardiac function, GPR55 exerted a protective role by maintaining the systolic function of high fat fed ApoE-/- mice, yet negatively affected the contractile reserve of these mice. With regard to infarct size, the present study established that LPI-induced activation of GPR55 (pre-global ischaemia) exacerbates myocardial tissue injury via a Rho-associated protein kinase (ROCK) dependent mechanism. Finally, this study established that LPI signals through the same signalling pathway as it did in the isolated heart, in both mouse and human-induced pluripotent stem cell-derived cardiomyocytes thus suggesting a translational role for GPR55 in the human heart. In conclusion, despite further research being required, the data presented within this thesis provides evidence that GPR55 may have the potential to be targeted for therapeutic gains in atherosclerosis and myocardial I/R injury.

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Orientador: Marcos Ferreira Minicucci / Coorientador: Sergio Alberto Rupp de Paiva / Coorientador: Paula Schmidt Azevedo Gaiolla / Banca: Leonardo Antonio Mamede Zornoff / Banca: Helio Vannucchi / Resumo: Introdução: A insuficiência cardíaca é uma frequente complicação após o infarto agudo do miocárido (IAM), sendo que a remodelação cardíaca apresenta papel de destaque nesse cenário. O aumento do estresse oxidativo e do processo inflamatório estão associados com a remodelação cardíaca após o IAM. Devido ao grande impacto sócio econômico e às altas taxas de mortalidade, torna-se relevante a identificação de outros fatores que modulem o processo de remodelação cardíaca e podemos destacar a suplementação de alimentos com propriedades antioxidantes, como o tomate (Lycopersicon esculentum), e um de seus principais constituintes, o licopeno. Objetivo: Avaliar a influência da suplementação de tomate e licopeno na remodelação cardíaca após o IAM. Materiais e métodos: Ratos Wistar machos, com peso entre 200 e 250g, foram submetidos ao infarto experimental ou à cirurgia simulada e alocados em seis grupos: 1) grupo Sham (animais submetidos à cirurgia simulada) alimentado com dieta padrão (grupo- SC); 2) grupo Sham alimentado com dieta suplementada com licopeno 1mg/kg peso corporal/dia (grupo-SL); 3) grupo Sham alimentado com dieta suplementada com tomate (grupo-ST); 4) grupo infartado (animais submetidos ao infarto experimental) alimentado com dieta padrão (grupo-IC); 5) grupo infartado alimentado com dieta suplementada com licopeno 1mg/kg de peso corporal/dia (grupo-IL); 6) grupo infartado alimentado com dieta suplementada com tomate (grupo-IT). O licopeno e o tomate das dietas foram diluídos em óleo de milho para serem adicionados à ração (0,5ml de óleo/kg de peso corporal/dia) e os grupos controles tiveram a mesma quantidade de óleo adicionado. Após três meses de observação os animais foram submetidos ao estudo funcional, morfométrico, e bioquímico. Os valores obtidos foram apresentados em média ± desvio padrão. As variáveis que não preencheram os critérios de normalidade e de... / Abstract: Introduction: Heart failure is a common complication after the acute myocardial infaction (AMI), and cardiac remodeling has a prominent role in this scenario. Increased oxidative stress and inflammation are associated with cardiac remodeling after AMI. Due to the great economic and social and high mortality rates, it's important to identify other factors that modulate the process of cardiac remodeling and among this factors are the supplementation of foods with antioxidant properties, such as tomato (Lycopersicon esculentum), and of its primary constituents, the lycopene. Objectives: Evaluate the influence of tomato and lycopene supplementation in cardiac remodeling after AMI. Methods: Male Wistar rats, weighing between 200 and 250g, were submitted to the experimental infarction or sham surgery and divided into six groups: 1) Sham group (animals undergoing sham surgery) fed a standard diet (SC group); 2) Sham group fed diet supplemented with 1 mg lycopene/kg body/day (SL group); 3) Sham group fed diet supplemented with tomato (ST group); 4) infarcted group (animals submitted to experimental infarction) fed a standard diet (IC group); 5) infarcted group fed diet supplemented with 1 mg lycopene/kg of body weight/day (IL group); 6) infarcted group fed diet supplemented with tomato (IT group). The lycopene and the tomato were dilute in corn oil to be add into the diet (0.5 ml of corn oil/kg body weight/day) and the standard group received the same oil. After three months of observation the animals underwent functional, morphometric and biochemical analysis. The values were expressed as mean ± standard deviation. The variables that did not meet the criteria of normality and equal variance were normalized before analysis. Comparisons between groups were made by two-way analysis of variance (ANOVA). For non-normalized data, we used Kruskal-Wallis test (comparison between the Sham groups, SC, SL and ... / Mestre

No Brasil, as doenças cardiovasculares constituem-se nas principais causas de mortalidade, sendo o infarto agudo do miocárdio a entidade nosológica mais freqüente dentre as doenças isquêmicas do coração. Os fatores de risco que predispõem as pessoas a essa doença estão relacionados a hábitos do estilo de vida e história familiar. Assim, esta investigação, de natureza descritiva, pretende identificar os fatores de risco relacionados ao meio ambiente, à biologia humana, estilo de vida, e sistema de saúde de pacientes internados em um hospital privado, até 48 horas após a ocorrência de infarto agudo do miocárdio, identificar o conhecimento quanto aos fatores de risco para o desenvolvimento de novos problemas de saúde e verificar se algumas variáveis, relacionadas aos fatores de risco de pacientes infartados em hospital público e privado, são semelhantes. O referencial teórico foi o Modelo de Campo de Saúde que compõe elementos relacionados ao meio ambiente, biologia humana, estilo de vida e sistema de saúde. Foram entrevistados 31 pacientes internados, em um hospital privado de uma cidade do interior do Estado de São Paulo, no período de janeiro a julho de 2003, após assinatura do termo de consentimento informado. Os resultados revelam que, quanto ao meio ambiente, a maioria dos pacientes era alfabetizada, 11 (35,5%) tinha o primeiro grau completo, 10 (32,2%) eram aposentados e donas-de-casa, 24 (77,4%) trabalhavam em torno de 8 a 10 horas por dia e tinham somente um emprego, e a renda familiar mensal, para 19 (61,3%), encontrava-se na faixa de 5 a 15 ou mais salários-mínimos, 22 (70,9%) eram casados e 15 (48,3%) tinham três ou mais filhos, 21 (67,7%) eram procedentes de Ribeirão Preto e região e todos residiam em zona urbana. Em relação à biologia humana, 19 (61,3%) eram do sexo masculino, aproximadamente metade 17 (54,8%) encontrava-se na faixa etária de 40 a 59 anos, 18 (58,1%) encontravam-se com sobrepeso ou obesidade classes I e II. Quanto aos antecedentes familiares, os dados mais expressivos apontam que 23 (74,2%) apresentavam hipertensão arterial sistêmica, 15 (48,3%) diabetes melittus, 17 (54,8%) infarto agudo do miocárdio e 6 (19,3%) acidente vascular cerebral. Das mulheres entrevistadas, 7 (22,6%) faziam uso algum tipo de terapia de reposição hormonal. No tocante ao estilo de vida relacionado aos hábitos alimentares, 29 (93,6%) utilizavam frituras nas refeições, 14 (45,2%) ingeriam doces e refrigerantes diariamente e 13 (41,9%) tomavam três xícaras ou mais de café ao dia, 18 (58,1%) faziam uso de bebidas alcoólicas, 10 (32,2%) eram fumantes, 9 (29,0%) ex-fumantes e 18 (58,1%) sedentários. Quanto ao estresse, 12 (38,7%) sentiam-se estressados no local de trabalho e 19 (61,3%) dormiam menos que oito horas por noite. Em relação ao sistema de saúde, 16 (51,6%) conheciam o diagnóstico, 12 (38,7%) apresentaram dúvidas acerca da doença, 21 (67,7%) utilizavam os serviços de saúde oferecidos pelo plano de saúde e 17 (54,8%) realizavam tratamento de hipertensão arterial sistêmica e diabetes melittus. Os dados revelam que os pacientes infartados estão expostos a hábitos autocriados que são passiveis de modificação havendo a necessidade de iniciar este processo educativo inclusive no período de internação hospitalar. / The cardiovascular diseases in Brazil, constitute nowadays death’s first cause and myocardial infarction is the most frequent nosological entity amonmg heart isquemical diseases. Among risk factors which predispose people committed by this disease are their life style’s and familiar history’s habits. This descriptive investigation intended to identify the risk factors related to the environment, human biology, life style and health systems of patients admitted in a private hospital, until 48 hours after the myocardial infarction; identify the knowledge’s blanket concerning to the risk factors related to new health problems’ development and verify if some variables are related to the risk factors which are similar to those of admitted patients in private and public hospitals. The theoretical referential used was the Health Model Field which constitutes the elements linked to the environment, human biology, life style an health system. We interviewed 31 internee patients in a private hospital in São Paulo’s interior, from January through July, 2003. Concerning to the environment 93,5% of the patients were literate; among them 11 (35,5%) had completed high school; related to their occupation 10 (32,2%) were retired and housewives; concerning to their working hours and job numbers, 24 (77,4%) work around 8 or 10 hours a day and have only one job; when referring to their familiar monthly income, 19 (61,3%) obtained from 5 to or more minimum salaries; 22 (70,9%) were married and 15 (48,3%) had three or more children; 21 (67,7%) were from Ribeirão Preto and its region and all of them lived in urban areas. When referring to the human biology, 19 (61,3%) were masculine and their ages varied between 40 and 59 years old; 18 (58,1%) were over weighted or fat, belonging to classes I and II; concerned to the familiar preceding, the most expressive data showed that 23 (74,2%) presented systemic arterial hypertension; 15 (48,3%) mellitus diabetes; 17 (54,8%) myocardial infarction and 6 (19,3%) cerebral vascular accident; 7 (22,6%) were feminine and were using hormones. Concerned to their life style, related to the feeding habits, 29 (93,6%) were accustomed to eat fried food; 14 (45,2%) used to eat sweeties and drink soft drinks daily; 13 (41,9%) used to drink 3 or more cups of coffee a day. When referring to the use of alcoholic drinks, 18 (58,1%) used to drink it; 10 (32,2%) were smokers and 9 (29,0%) were ex-smokers; 18 (58,1%) were sedentary. When referring to the stressing environment and sleeping patterns, 12 (38,7%) mention the work place and 19 (61,3%) sleep less than 8 hours a day. Concerning to the health system, 16 (51,6%) knew their diagnosis; 12 (38,7%) presented doubts about their diseases; 21 (67,7%) used the health services offered by their health insurance and 17 (54,8%) were under arterial hypertension and mellitus diabetes treatment. The data showed the patients who suffered by myocardial infarction are exposed to “selfcreated” habits, which may be modified and it is important to mention the necessity of raising educative programs including the patient’s permanence at the hospital.

This diploma thesis deals with the role of nutrition in the prevention and treatment of cardiovascular diseases. The theoretical part describes basic knowledge about cardiovascular diseases, prevalence, risk factors and the importance of nutrition in their prevention and treatment. The theoretical part describes in detail the effect of intake of carbohydrates, fiber, describes the role of glycemic index of foods, fat intake and their chemical composition, minerals, alcohol and coffee. One part of the theoretical part also describes the role of nutrition in the treatment. The research part is devoted to the dietary habits of patients who have already had an acute myocardial infarction. The aim of the research is to find out whether patients follow current recommendations for the prevention and treatment of CVD, or how the actual diets of these patients differ from recommendations. The data were collected using a questionnaire filled in during interviews with selected patients. It was found out that patients hospitalized for acute myocardial infarction have insufficient knowledge to build a balanced diet, or that nutritional recommendations are consciously violated. Problematic is especially the choice of fats, the unbalanced composition of the diet, the frequent consumption of too fat and sweet...