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.

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...

<p>Validerat; 20101217 (root)</p>

Clinical and preclinical studies revealed that heart failure induces depression. Injury of myocardial tissue initiates an inflammation cascade that extends to the CNS and might contribute to depression following myocardial infarction (MI). Sex differences were noticed in the progression of heart failure and depression in clinical studies. We hypothesized that depression-like behavior induced by HF post-MI is influenced by sex through modulation of inflammation pathway. First, we evaluated sex differences in depression-like behavior in male and female rats at 8-10 weeks post-MI, as well as circulating cytokines, the extent of inflammation in the PFC, PVN, and amygdala, and mBDNF levels in the PFC and amygdala that are affected by neuroinflammation. Then we evaluated the effect of ovariectomy (OVX) and whether estrogen replacement with 17β-estradiol (E2) prevents post-MI induced depression-like behavior through inhibiting neuroinflammation. Thirdly we evaluated the role of inflammation for cardiac dysfunction and development of depression-like behavior in OVX female rats post-MI by oral treatment with pentoxifylline (PTX). Male rats developed depression-like behavior by ten weeks post-MI but not females as assessed by sucrose preference test (SPT) and forced swim test (FST). Both developed similar cardiac dysfunction and a comparable increase in plasma and PVN cytokine levels, but cytokine levels increased and mBDNF levels decreased only in the PFC of male rats post-MI. OVX per se decreased sucrose consumption and induced passive behavior assessed by SPT and FST, respectively.The combination of MI and OVX aggravated depression-like behvaiour. E2 treatment prevented the development of mild depression-like behavior in OVX and severe symptoms in OVX female rats post-MI. E2 had no effect on cardiac dysfunction in OVX female rats at 10 weeks post-MI. Despite the similar increase in circulating cytokines in OVX ± E2 at 10 weeks post-MI, E2 decreased the proinflammatory cytokines and increased IL-10 (anti-inflammatory cytokine) in the PFC. Finally, we evaluated the role of neuroinflammation in depression-like behavior in OVX female rats post-MI through inhibiting cytokine production by administering oral PTX. PTX prevented depression-like behavior in OVX female rats post-MI and reduced cytokines levels in plasma, PVN and PFC. However, PTX did not affect the progression of cardiac dysfunction at 10 weeks post-MI. Sex determines the development of depression-like behavior in HF post-MI and neuroinflammation appears to play a critical pathway that is affected by sex and can be inhibited by hormonal replacement or anti-inflammatory agents.

Successful treatment of myocardial infarction requires anearly and accurate diagnosis. Recent studies have shown thatacute myocardial scintigraphy has a high predictive value forprognosis of myocardial events. Three dimensional (3D)perfusion data obtained with SPECT are however very rare in theemergency department (ED). We have developed a mobile tomographic system for myocardialscintigraphy, which can be used in the ED. The objectives ofthe studies presented were:     To develop software and hardware for a mobile tomographicgamma camera system: the Cardiotom     To demonstrate that a mobile tomographic system can beused in a clinical situation     To evaluate the limitations of Ectomography when usingfiltered back projection for reconstruction     To develop a method of reconstruction that compensatesfor the incomplete data acquisition associated with theacquisition geometry of Ectomography Three prototypes of a mobile tomographic gamma camera systemhave been designed and built at the Division of MedicalEngineering, which all have been used in a clinical setting.The systems are based on Ectomography, a limited view anglemethod, also developed by us. Instead of rotating the entiregamma camera detector around the patient as in SPECT, a slanthole collimator is rotated in front of a stationary detector.Since short imaging times are important in the ED and the heartonly occupies a small area of the detector, system sensitivityhas been increased by dividing the collimator into segmentswith different projection directions. In myocardial imaging, 4segments are used and within 10 minutes from the start ofacquisition, reconstructed short axis view sections areavailable for interpretation. Using the Cardiotom in an experimental animal study, weverified that the system could be used to quantify myocardialarea at risk and final infarct size. This conclusion was madefrom a comparison of images obtained from the Cardiotom andpathological staining of the myocardium, analysedpost-mortem. Inherent limitations of Ectomography were evaluated withboth phantom studies and computer simulated data, reconstructedusing filtered back-projection Results show that moderatedeviation from optimal position of the detector with respect tothe myocardium will have little or no influence on thediagnostic information when assessed from short axis sectionimages and polar tomograms. However, long axis section imagesappear elongated when reconstructed using filteredback-projection. We have shown that this elongation distortion can besuppressed using iterative reconstructions techniques, and wehave implemented such an algorithm, called three-dimensionalTotal Variation Expectation Maximisation (3DTV-EM). Resultswere that elongation distortion was reduced and depthresolution improved. The reconstruction technique was alsoevaluated for SPECT reconstruction and was found to decreasethe noise in reconstructed images, when compared to thetwo-dimensional TV-EM algorithm. Noise pattern were also foundto be more uniform for the 3DTV-EM algorithm compared totwo-dimensional TV-EM. In conclusion, we have shown that the Cardiotom may beuseful in a clinical acute setting, providing valuablediagnostic information. Rapid positioning is possible, sincemoderate deviation from optimal positioning will cause few orno artefacts. Image quality can be improved if iterativetechniques are used for image reconstruction instead offiltered back-projection. <b>Keywords</b>: acute studies, myocardial infarction,scintigraphy, mobile gamma camera, tomography.

The incidence of stroke and re-infarction is noticeably high in the first few days following acute myocardial infarction. This finding has raised questions whether the systemic inflammatory reaction secondary to myocardial necrosis is involved. The inflammation might affect the activation of platelets leading to insufficient effect of the antiplatelet treatment given. Furthermore, the importance of platelet reactivity and inflammation in terms of long-term prognosis is not fully understood. The prognostic importance of C-reactive protein (CRP) in relation to clinical variables also needs to be clarified. The present studies are aimed at describing the dynamics of platelet function during the first days of an acute myocardial infarction, in relation to diabetes and inflammation. We also investigated whether increased platelet reactivity or the increased concentration of CRP in blood were related to a worse outcome. Finally, we examined if CRP levels contributed to a predictive model using clinical variables known to affect outcome in patients with AMI.  We used two novel platelet function tests to measure platelet reactivity; the PA-200 (a laser light aggregometer) and the PFA-100 (measures primary haemostasis in whole blood). Platelet aggregation increased during the initial course of an acute myocardial infarction. The increase in platelet aggregation was most pronounced in diabetics and in patients showing higher systemic inflammatory reaction, assessed by measuring the concentration of CRP in blood. The pronounced platelet aggregation occurred despite ongoing antiplatelet and antithrombotic treatment. There was a significant association between the levels of CRP and the degree of platelet reactivity. However, while the CRP levels were associated with a worse outcome (AMI, stroke and death), the results of the platelet function tests were not. The importance of CRP in predicting prognosis depended on which adjustments were made for confounding factors. CRP and prognostic variables in a statistical model predicting death, however, showed that CRP was excluded. Thus CRP did not predict outcome beyond clinical prognostic variables. The results of these studies reinforce the importance of clinical variables such as heart failure, age, atrial fibrillation, smoking status, diabetes and impaired kidney function - all of which were associated with worse prognosis in multivariable analysis.

Optical methods can provide useful tissue characterization tools. For this project, two-photon microscopy and polarized light examinations (polarimetry) were used to assess the organizational state of myocardium in healthy, infarcted, and stem-cell regenerated states. Two-photon microscopy visualizes collagen through second-harmonic generation and myocytes through two-photon excitation autofluorescence, providing information on the composition and structure/organization of the tissue. Polarimetry measurements yield a value of linear retardance that can serve as an indicator of tissue anisotropy, and with a dual-projection method, information about the anisotropy axis orientation can also be extracted. Two-photon microscopy results reveal that stem-cell treated tissue retains more myocytes and structure than infarcted myocardium, while polarimetry findings suggest that the injury caused by temporary ligation of a coronary artery is less severe and more diffuse that than caused by a permanent ligation. Both these methods show potential for tissue characterization.

Optical methods can provide useful tissue characterization tools. For this project, two-photon microscopy and polarized light examinations (polarimetry) were used to assess the organizational state of myocardium in healthy, infarcted, and stem-cell regenerated states. Two-photon microscopy visualizes collagen through second-harmonic generation and myocytes through two-photon excitation autofluorescence, providing information on the composition and structure/organization of the tissue. Polarimetry measurements yield a value of linear retardance that can serve as an indicator of tissue anisotropy, and with a dual-projection method, information about the anisotropy axis orientation can also be extracted. Two-photon microscopy results reveal that stem-cell treated tissue retains more myocytes and structure than infarcted myocardium, while polarimetry findings suggest that the injury caused by temporary ligation of a coronary artery is less severe and more diffuse that than caused by a permanent ligation. Both these methods show potential for tissue characterization.