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Influência do gene da enzima conversora de angiotensina sobre as respostas metabólicas induzida pelo treinamento físico aeróbio em camundongos diabéticos / Influence of angiotensin converting enzime gene on metabolic responses induced by aerobic physical training in diabetic miceBergamo, Fábio Carvalho 24 February 2011 (has links)
O objetivo do presente estudo foi avaliar os efeitos do treinamento físico (TF) sobre as alterações do metabolismo energético induzidas pelo diabetes em camundongos com 1 e 3 cópias do gene da enzima conversora de angiotensina (ECA). Para isso, camundongos machos C57BL/6 geneticamente modificados com 1 e 3 cópias do gene da ECA foram induzidos ao diabetes por estreptozotocina (STZ), e separados em 4 grupos de acordo com a realização ou não de TF com natação: 1 cópia sedentário (1S, n=14), 1 cópia treinado (1T, n=15), 3 cópias sedentário (3S, n=10), e 3 cópias treinado (3T, n=11). Os principais resultados foram: não houve diferença no ganho de peso corporal, porém o peso do depósito de gordura retroperitoneal e diâmetro de adipócito foram menores no grupo 3T comparado ao 1S, 1T e 3S; menor consumo de ração diária do 1S comparado ao 1T, 3S e 3T; maior consumo de oxigênio de repouso do 3S comparado ao 1T e 3T; melhor capacidade de realizar exercício físico e menor glicemia de jejum do 1T comparado ao 1S e 3S (1T=305±34 vs. 1S=479±47 e 3S=496±49 mg/dl); maior concentração de leptina no 1T comparado ao 1S (1T=5,65±0,33 vs 1S=4,07±0,43 ng/ml) xi e maior atividade lipolítica no 1T comparada aos grupos 1S, 3S e 3T (1T=288±50 nmol/106cels/h vs. 1S=79±37, 3S=123±37 e 3T=50±20 nmol/106cels/h); Não houve diferença estatística entre os grupos na tolerância à glicose, na atividade da enzima lipogênica ácido graxo sintase, na atividade da enzima citrato sintase, na tipagem de fibras e na razão capilar/fibra muscular do músculo sóleo. Esses resultados demonstraram que as adaptações metabólicas promovidas pelo TF no diabetes são parcialmente associadas ao genótipo da ECA / The main purpose of this study was to evaluate the effects of physical training (PT) on changes in energy metabolism induced by diabetes in mice harboring 1 and 3 copies of angiotensin converting enzyme (ACE) gene. For this, transgenic adult male mice (C57BL/6) with 1 or 3 copies of ACE gene were induced to diabetes by Streptozotocin (STZ) and separated into groups sedentary or physical trained with swimming: 1 copy sedentary (1S, n = 14), 1 copy trained (1T, n = 15), 3 copies sedentary (3S, n = 10) and 3 copies trained (3T, n = 11). The main results were: body weight gain was not different among groups, but 3T group reduced retroperitoneal fat pad and adipocyte diameter compared to 1S, 1T and 3S groups; daily food intake was lower in 1S compared to 1T, 3S and 3T groups; resting oxygen uptake was higher in 3S compared to 1T and 3T; physical exercise ability increased and fasting glucose decreased only in 1T group compared to 1S and 3S (1T=305±34 vs. 1S=479±47 e 3S=496±49 mg/dl); serum leptin increased in 1T compared to 1S (1T=5,65±0,33 vs 1S=4,07±0,43 ng/ml), and lipolytic activity was higher in 1T compared to 1S, 3S and 3T groups (1T=288±50 nmol/106cels/h vs. 1S=79±37, 3S=123±37 e 3T=50±20 nmol/106cels/h). There were no statistical differences among groups in glucose tolerance, lipogenic activity of fat acid synthase, activity of citrate synthase enzyme, fibre type composition and capillary-to-fibre ratio of soleous muscle. These results demonstrated that metabolic adaptations promoted by PT in diabetes are partially associated with ACE genotype
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Déterminants du pronostic de la maladie coronarienne stable / Determinants of the prognosis of stable coronary artery diseaseSorbets, Emmanuel 18 September 2017 (has links)
Les patients coronariens stables ou stabilisés sont à haut risque d’évènements cardiovasculaires. Ils représentent une population hétérogène avec une présentation clinique, un terrain et un pronostic pouvant être extrêmement variables d’un patient à l’autre. Pourtant, d’après les recommandations internationales, tous doivent bénéficier d’une prise en charge relativement comparable basée sur des essais cliniques réalisés dans des sous-populations restreintes de patients stables et instables, pour la plupart anciens, et ne correspondant plus à la prise en charge actuelle des patients. Préciser les déterminants du pronostic de cette population, et notamment les stratégies thérapeutiques, est un enjeu majeur.Les antagonistes du système rénine-angiotensine (IEC/ARA2) font partie de l’arsenal médicamenteux de tout patient coronarien. Pourtant leur intérêt, en association aux antiagrégants plaquettaires et statines, est incertain chez les patients sans dysfonction ventriculaire gauche qui constituent un sous-groupe important parmi les patients stables.Le registre international REACH a évalué l’impact des IEC/ARA2 dans cette population avec 4 ans de suivi. La méthodologie statistique utilisée a été une analyse observationnelle avec ajustement ou avec appariement selon le score de propension. Il n’a pas été mis en évidence de bénéfice des IEC/ARA2 sur le critère de jugement principal composite associant décès cardiovasculaire – IDM – AVC, de même que sur le critère de jugement secondaire associant décès cardiovasculaire – IDM – AVC – Hospitalisation pour évènement athéro-thrombotique ou sur les critères tertiaires comprenant individuellement chacun des critères de jugement secondaire ainsi que sur la mortalité toute cause. Enfin il n’est pas ressorti non plus de bénéfice franc dans les sous-groupes d’analyse. Les résultats ont été concordants lorsque les analyses ont été réalisées pour les IEC seuls ou pour les ARA2 seuls, et ont été confortés par diverses analyses de sensibilité.Ces données méritent confirmation dans une cohorte indépendante. C’est l’un des objectifs du registre CLARIFY, registre de 32703 patients coronariens stables ou stabilisés, dont le suivi à 5 ans est terminé. Dans ce registre contemporain international, le taux global à 5 ans de mortalité toute cause a été de 7,9%, de mortalité non cardiovasculaire de 5% et de mortalité cardiovasculaire de 2,9%. Un évènement cardiovasculaire comprenant infarctus du myocarde (fatal ou non), angor instable, revascularisation coronaire par angioplastie ou pontage est survenu chez 15,9% des patients.Tout comme les IEC/ARA2, l’impact des bétabloquants dans la prise en charge du coronarien stable ou stabilisé, sans dysfonction ventriculaire est également controversé. Cette classe médicamenteuse est en cours d’évaluation dans CLARIFY. L’analyse tient compte du type de bétabloquant, de la dose prescrite, des éventuelles intolérances amenant à modifier leur utilisation, de la présence et de l’ancienneté d’un infarctus du myocarde et la fraction d’éjection ventriculaire gauche.CLARIFY a également pour objectif d’approfondir les déterminants du pronostic de la maladie coronarienne stable, avec une analyse spécifiquement focalisée sur la présence de symptômes angineux, d’ischémie myocardique et sur leur combinaison, en fonction de l’utilisation des méthodes de revascularisation myocardiques, pour mieux comprendre les mécanismes responsables des évènements cardiovasculaires et évoluer vers une prise en charge plus personnalisée. / Stable or stabilized coronary artery disease patients are at high risk for cardiovascular events. They represent a heterogeneous population. The clinical presentation, the context and the prognosis can be extremely variable from one patient to another. However, according to the international guidelines, those patients should be given a relatively comparable treatment based on clinical trials realized in restricted subpopulations of stable and unstable patients. Most of these trials are old, and no longer correspond to the current management. Specifying the determinants of the prognosis of this population, and in particular the therapeutic strategies, is a major challenge.The antagonist receptors of renin-angiotensin system (ACEI/ARB) are a part of the treatment of any coronary artery disease patient. Yet their interest in the prognosis of this population without left ventricular dysfunction in association with antiplatelet agents and statins is uncertain.The contemporary REACH registry has assessed the impact of ACEI/ARB in this population with a 4-year of follow-up. The statistical methodology used was based on the propensity score. After adjustment or matching with the propensity score, there was no benefit of ACEI/ARB on the primary endpoint of cardiovascular death - MI - stroke. No benefit was found on the secondary endpoint of cardiovascular death - MI - stroke - hospitalization for atherothrombotic events. No benefit was found on the tertiary criteria including individually each of the secondary endpoints and on any cause mortality. Finally,there was no clear benefit in the analyzes subgroups. These results were consistent when the analyzes were performed for ACEI alone or for ARB alone. They were also supported by sensitivity analyzes.These data should be confirmed or reversed in an independent cohort. This will be one of the many objectives of the CLARIFY registry, that enrolled 32,703 stable or stabilized coronary artery disease patients. The 5-year follow-up is complete. In this international contemporary registry, the overall 5-year rate of total mortality was 7.9%, non-cardiovascular mortality was 5% and cardiovascular mortality was 2.9%. A cardiovascular event including myocardial infarction (fatal or not), unstable angina, coronary revascularization by angioplasty or bypass surgery occured in 15.9% of patients.Like ACEI/ARB, the impact of betablockers on the management of stable or stabilized coronary artery disease without left ventricular dysfunction is also controversial. This drug class is being evaluated in CLARIFY. The analyzis takes into account the type of beta-blocker, the prescribed dose, any intolerance leading to changes in their use, the history of a myocardial infarction, and the left ventricular ejection fraction.CLARIFY will help to more define the determinants of the prognosis of stable coronary artery disease, with a more particular focus on symptomatic or not, ischemic or not, and revascularized or not, in order to better understand the mechanisms responsible for cardiovascular events, and evolve towards a more personalized and cost-effective care.
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Factors influencing the risk of diabetic nephropathy : analyses of genes, smoking and dietMöllsten, Anna January 2006 (has links)
Diabetic long-term complications, despite intensive treatment, cause serious handicaps at relatively young age in diabetic patients. Diabetic nephropathy (DN) develops in up to 30% of patients with type 1 diabetes (T1D). Besides the eventual loss of kidney function, with need for dialysis treatment and transplantation, this complication also increases the risk of early death from cardiovascular disease. In addition to hyperglycaemia, the risk of developing DN is influenced by a number of life-style related factors, such as smoking and diet, but the mechanisms of action of these factors are largely unknown. The incidence of DN is not linearly related to diabetes duration. There is a peak incidence of DN at 15-20 years and this, together with results from family studies, shows that genetic factors are important contributors. Possible candidate genes are those involved in regulation of intraglomerular pressure and blood pressure, oxidative stress and inflammation. The main aims of this thesis were: ● To investigate the risk of DN associated with polymorphisms in; A) the endothelial NO-synthase gene (NOS3) and genes in the renin-angiotensin-system (RAAS) (all involved in the regulation of intraglomerular pressure). B) the manganese superoxide dismutase gene (SOD2) (involved in the regulation of oxidative stress). C) the ICAM1 gene (involved in activation and migration of lymphocytes) ● To investigate gene-smoking interactions ● To investigate the influence of normal diet on risk of microalbuminuria. The aims were addressed in different case-control settings, including 347 T1D patients from Sweden and 1163 patients from Finland, with or without DN, defined as; overt DN – having albumin excretion rate (AER) ≥200 μg/min, incipient DN – AER between 20 and 200 μg/min, non-DN controls – having AER <20 μg/min and at least 20 years of diabetes duration. In one study also non-diabetic healthy individuals were included to asses the risk of T1D associated with the ICAM1 gene. Results: The RAAS genes were investigated in the Swedish sample set and there was an association between a polymorphism in the angiotensin II type 1 receptor (AGTR1) gene and overt DN, when adjusting for age, duration of diabetes, HbA1c, sex and smoking (adjusted OR=3.04, 99% CI=1.02-9.06). Also a synergistic interaction with smoking was indicated. The ICAM1 gene was investigated in the Swedish sample set, but no association with DN was found. There were, however, associations between T1D and two polymorphisms in this gene, rs281432 (OR=1.64, 95% CI=1.14-2.38) and rs5498 (OR=2.46, 95% CI=1.59-3.80). In the combined Swedish/Finnish sample set, the Glu/Glu genotype of the Glu298Asp polymorphism in the NOS3 gene was associated with DN when age at diabetes onset, duration of diabetes, HbA1c, blood pressure, sex and smoking were taken into account (adjusted OR=1.46, 95% CI=1.12-1.91). There was also association between a polymorphism in the MnSOD gene and DN in this sample set. Homozygosity for the valine-allele of the Val16Ala polymorphism was associated with increased risk of DN in a model including age at diabetes onset, duration of diabetes, HbA1c, sex and smoking (adjusted OR=1.32, 95% CI=1.00-1.74). Smoking was associated with DN (OR=2.00, 95% CI=1.60-2.50) and in the Swedish sample set there were indications of interactions between smoking and the NOS3 and SOD2 genes, but these results could not be confirmed in the Finnish sample set. A high protein intake can enhance glomerular filtration rate and accelerate progression to DN, also other dietary components such as fat, fibres, vitamins and the ratio red/white meat have been discussed as important for DN development. In a nested case-control study including young T1D patients, the normal dietary intakes of protein and other nutrients were assessed using a semiquantitative questionnaire. The results showed that T1D patients consuming more than 6.5 g fish protein (>75th percentile) per day were at slightly lower risk to have microalbuminuria in both crude (OR=0.49, 95% CI=0.25-0.97) and adjusted analyses (OR=0.26, 95% CI=0.09-0.76, adjusted for age, duration of diabetes, sex, HbA1c, mean arterial pressure, BMI, region, smoking, energy intake and fish fat intake). Conclusions: The risk of having diabetic nephropathy is influenced by at least two genes controlling blood pressure and one gene protecting against oxidative stress. Smoking also increases the risk of DN and our findings indicate that smoking may accentuate the effect of the AGTR1, NOS3 and SOD2 genes. Normal dietary intake of protein was not associated with risk of having microalbuminuria in young T1D patients, on the other hand, an intake of fish protein above the 75th percentile decreased the risk of microalbuminuria.
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Angiotensin II Proteomic Signature in Human Proximal Tubular Cells as a Predictor of Renin Angiotensin System Activity in Kidney DiseasesKonvalinka, Ana 22 July 2014 (has links)
Angiotensin II (AngII), the major effector of the renin angiotensin system, mediates kidney disease progression by signalling through AT-1 receptor (AT-1R), but there are no specific measures of renal AngII activity. Accordingly, we sought to define an AngII-regulated proteome in primary human proximal tubular cells (PTEC) in order to identify potential AngII activity markers in the kidney. We utilized stable isotope labelling with amino acids (SILAC) in PTECs to compare proteomes of AngII-treated and control cells. Of 4618 quantified proteins, 83 were differentially regulated. SILAC ratios for 18 candidates were confirmed by Selected Reaction Monitoring (SRM) assays. Both SILAC and SRM revealed the nuclear factor erythroid 2-related 2 (Nrf2) target protein, heme oxygenase-1 (HO-1) as the most significantly upregulated protein in response to AngII stimulation. AngII-dependent regulation of HO-1 gene and protein was further verified by qRT-PCR and ELISA in PTECs. In order to extend these in vitro observations, we utilized a systems biology approach. We thus overlaid a network of significantly enriched gene ontology (GO) terms from our AngII-regulated proteins with a dataset of differentially expressed kidney genes from AngII-treated wild type mice and AT-1R knock-out mice. Five GO terms were enriched both in vitro and in vivo, and all included HO-1. Furthermore, four additional Nrf2 target proteins were functionally important in vitro and in vivo. We then studied HO-1 kidney expression and urinary excretion in AngII-treated wild type mice and mice with PTEC-specific AT-1R gene deletion. Deletion of the AT-1R gene in PTECs lowered both kidney expression and urine excretion of HO-1, confirming AngII/AT-1R mediated regulation of HO-1. In summary, our in vitro experiments identified novel molecular markers of AngII activity in PTECs and the animal studies demonstrated that these markers also reflect AngII activity in PTECs in vivo. These interesting proteins hold promise as specific markers of renal AngII activity in patients and in experimental models.
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Influência do gene da enzima conversora de angiotensina sobre as respostas metabólicas induzida pelo treinamento físico aeróbio em camundongos diabéticos / Influence of angiotensin converting enzime gene on metabolic responses induced by aerobic physical training in diabetic miceFábio Carvalho Bergamo 24 February 2011 (has links)
O objetivo do presente estudo foi avaliar os efeitos do treinamento físico (TF) sobre as alterações do metabolismo energético induzidas pelo diabetes em camundongos com 1 e 3 cópias do gene da enzima conversora de angiotensina (ECA). Para isso, camundongos machos C57BL/6 geneticamente modificados com 1 e 3 cópias do gene da ECA foram induzidos ao diabetes por estreptozotocina (STZ), e separados em 4 grupos de acordo com a realização ou não de TF com natação: 1 cópia sedentário (1S, n=14), 1 cópia treinado (1T, n=15), 3 cópias sedentário (3S, n=10), e 3 cópias treinado (3T, n=11). Os principais resultados foram: não houve diferença no ganho de peso corporal, porém o peso do depósito de gordura retroperitoneal e diâmetro de adipócito foram menores no grupo 3T comparado ao 1S, 1T e 3S; menor consumo de ração diária do 1S comparado ao 1T, 3S e 3T; maior consumo de oxigênio de repouso do 3S comparado ao 1T e 3T; melhor capacidade de realizar exercício físico e menor glicemia de jejum do 1T comparado ao 1S e 3S (1T=305±34 vs. 1S=479±47 e 3S=496±49 mg/dl); maior concentração de leptina no 1T comparado ao 1S (1T=5,65±0,33 vs 1S=4,07±0,43 ng/ml) xi e maior atividade lipolítica no 1T comparada aos grupos 1S, 3S e 3T (1T=288±50 nmol/106cels/h vs. 1S=79±37, 3S=123±37 e 3T=50±20 nmol/106cels/h); Não houve diferença estatística entre os grupos na tolerância à glicose, na atividade da enzima lipogênica ácido graxo sintase, na atividade da enzima citrato sintase, na tipagem de fibras e na razão capilar/fibra muscular do músculo sóleo. Esses resultados demonstraram que as adaptações metabólicas promovidas pelo TF no diabetes são parcialmente associadas ao genótipo da ECA / The main purpose of this study was to evaluate the effects of physical training (PT) on changes in energy metabolism induced by diabetes in mice harboring 1 and 3 copies of angiotensin converting enzyme (ACE) gene. For this, transgenic adult male mice (C57BL/6) with 1 or 3 copies of ACE gene were induced to diabetes by Streptozotocin (STZ) and separated into groups sedentary or physical trained with swimming: 1 copy sedentary (1S, n = 14), 1 copy trained (1T, n = 15), 3 copies sedentary (3S, n = 10) and 3 copies trained (3T, n = 11). The main results were: body weight gain was not different among groups, but 3T group reduced retroperitoneal fat pad and adipocyte diameter compared to 1S, 1T and 3S groups; daily food intake was lower in 1S compared to 1T, 3S and 3T groups; resting oxygen uptake was higher in 3S compared to 1T and 3T; physical exercise ability increased and fasting glucose decreased only in 1T group compared to 1S and 3S (1T=305±34 vs. 1S=479±47 e 3S=496±49 mg/dl); serum leptin increased in 1T compared to 1S (1T=5,65±0,33 vs 1S=4,07±0,43 ng/ml), and lipolytic activity was higher in 1T compared to 1S, 3S and 3T groups (1T=288±50 nmol/106cels/h vs. 1S=79±37, 3S=123±37 e 3T=50±20 nmol/106cels/h). There were no statistical differences among groups in glucose tolerance, lipogenic activity of fat acid synthase, activity of citrate synthase enzyme, fibre type composition and capillary-to-fibre ratio of soleous muscle. These results demonstrated that metabolic adaptations promoted by PT in diabetes are partially associated with ACE genotype
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Efeitos sequenciais do treinamento aeróbio sobre o sistema renina angiotensina plasmático e cardíaco de SHR: análise do estresse oxidativo, perfil inflamatório e remodelamento cardíaco. / Sequential effects of aerobic training on the plasma and cardiac renin angiotensin system in SHR. Analysis of oxidative stress, inflammatory profile and cardiac remodeling.Sebastião Donato Silva Júnior 08 July 2016 (has links)
A hipertensão arterial é acompanhada de hiperatividade do sistema renina angiotensina (SRA). Demonstramos em ratos SHR que a hiperativação do SRA plasmático antecede o cardíaco. A hiperatividade do SRA foi acompanhada de aumento do estresse oxidativo, perfil inflamatório, hipertrofia cardíaca e deposição de colágeno no ventrículo esquerdo (VE) de SHR. O treinamento aeróbio de baixa a moderada promoveu pronta redução do SRA cardíaco e plasmático seguido por normalização do estresse oxidativo e redução da inflamação no VE. Embora não houve alteração na hipertrofia cardíaca, observamos redução da deposição de colágeno no VE de SHR treinados. Sugerimos que a redução do SRA foi determinante na modulação dos parâmetros analisados contribuindo para a manutenção das estruturas cardíacas e evitando remodelamento cardíaco deletério nos SHR treinados. / The hypertension is followed by renin angiotensin system hyperactivity (RAS). We have showed in SHR rats that plasma RAS hyperactivity precedes the cardiac RAS hyperactivity. Furthermore the RAS hyperactivity was followed by oxidative stress and inflammation increase as well as left ventricle (LV) collagen deposition in SHR. The aerobic training promoted prompt cardiac and plasma RAS activity reduction. It was followed by oxidative stress normalization and inflammatory reduction. Although we did not observe cardiac hypertrophy change, the collagen deposition was reduced in SHR trained group. We suggest the RAS activity reduction as a determinant condition to the beneficial adaptations occurred in the parameters analyzed. Thus contributing to maintenance of cardiac structures and avoids the deleterious cardiac remodeling in SHR.
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Ação concomitante da irradiação e quimioterapia no coração de ratas Wistar / Concurrent Action of Irradiation and Chemotherapy at Wistar Rats HeartsCamila Salata 15 July 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O Câncer de mama (CM) é hoje o tipo de câncer mais incidente entre as mulheres, com a estimativa de 53 mil novos casos para o ano de 2013, segundo o Instituto Nacional do Câncer (INCA). É considerada uma doença de bom prognóstico, principalmente quando diagnosticada na sua fase mais precoce. A evolução no diagnóstico, e nas técnicas de tratamento para o CM, que incluem a quimioterapia e/ou radioterapia, aumentaram a expectativa de sobrevida para este tipo de câncer. Uma das complicações tardias induzidas pelo tratamento desta doença é a cardiotoxicidade. O termo cardiotoxicidade abrange uma série de efeitos colaterais, que incluem arritmias, alterações na pressão arterial, isquemia do miocárdio, trombose ou insuficiência cardíaca. É, por isso, fundamental entender os mecanismos envolvidos no desenvolvimento da toxicidade cardíaca para o sucesso do tratamento dos pacientes com CM. Este trabalho teve como objetivo avaliar os efeitos cardíacos tardios induzidos pela irradiação e quimioterapia, simulando um tratamento para o CM, em ratas Wistar. Ratas Wistar, com aproximadamente 3 meses de idade, foram divididas em: grupo controle, grupo que recebeu quimioterapia + irradiação (TC+IR), e grupo que recebeu apenas irradiação (IR). A quimioterapia foi administrada em 4 ciclos, com intervalo de 1 semana entre eles. A irradiação na região do coração foi realizada em dose única, de 20Gy, em um campo de 2x2 cm2. Os ratos foram submetidos à eutanásia 5 meses após o término dos tratamentos, para que os efeitos tardios pudessem ser avaliados. Vários estudos foram conduzidos: ecocardiografia para observar as alterações funcionais do coração; PCR em tempo real para detectar alterações no nível mRNA de procolágeno tipo I, TGF-β1, angiotensinogênio, renina, ECA, AT1, VEGF e razão Bax/;bcl2, no tecido do ventrículo esquerdo (VE); Além de ensaios histológicos para avaliar o aspecto do tecido cardíaco do VE. Resultados e discussão Os resultados obtidos indicam um processo de remodelamento cardíaco após os tratamentos para o CM. Sugere-se que este remodelamento inicie-se com a diminuição de vasos no VE, causada pelos tratamentos, conforme os resultados da estereologia e do PCR para VEGF. Em seguida mostrou-se hipertrofia dos cardiomiócitos, o aumento da expressão de procolágeno e TGF-β1 e de tecido conjuntivo neste tecido. E associado a estes resultados, mostrou-se a participação dos sistema renina angiotensina cardíaco neste processo de remodelamento. Porém, apesar de todas estas alterações terem ocorrido em ambos os grupos tratados, apenas o grupo que recebeu irradiação e quimioterapia concomitantemente apresentou alteração da função cardíaca, na ecocardiografia. Sugere-se, desta forma, que a associação destas terapias seja mais lesiva ao coração, do que a irradiação aplicada exclusivamente. Conclusão Os objetivos do trabalho foram alcançados, e pode-se entender melhor as vias envolvidas na cardiotoxicidade. Este é um estudo inédito, o assunto abordado é recente, e de sumo importância para o desenvolvimento de novas estratégias de tratamento para o CM, onde sejam consideradas as complicações cardíacas tardias envolvidas. / Breast cancer (BC) is today the most frequent type of cancer among women, there were estimated 53 000 new cases for the year 2013, according to the National Cancer Institute (INCA). It is considered a disease of good prognosis, especially when diagnosed in early stages. The developments in the diagnosis, and treatment techniques for the BC, which include chemotherapy and/or radiotherapy, increased the survival rates for this type of cancer. One late complication induced by BC treatment is the cardiotoxicity. The cardiotoxicity term comprises different cardiotoxic side effects, which includes arrhythmia, blood pressure alterations, myocardial ischemia, thrombosis or congestive heart failure. It is, therefore, essential to understand the mechanisms involved in the development of cardiac toxicity for the successful treatment of patients with BC. This study aimed to evaluate the late cardiac effects induced by irradiation and chemotherapy, simulating a treatment for BC in Wistar rats. Wistar rats, about 3 months old, were divided into control group; a group receiving chemotherapy + irradiation (TC+IR), and a group that received only irradiation (IR). Chemotherapy was administered in 4 cycles, with an one week interval between them. The irradiation at the heart area was performed in a single dose of 20 Gy, and a field of 2x2 cm2. The rats were euthanized 5 months after the end of treatments, so the late effects could be evaluated. Several studies were conducted: echocardiography to observe the heart functional changes, real-time PCR to detect alterations in mRNA level of procollagen type I, TGF-β1, angiotensinogen, renin, ACE, AT1, VEGF and Bax/bcl2 ratio, in the left ventricle (LV) tissue; The LV cardiac tissue was also evaluated by assays. The results indicate a process of cardiac remodeling after the BC. It is suggested that this remodeling starts with a reduction of the cardiac vessels, induced by treatments, according the results of stereology, and the PCR for VEGF. Then, it was showed a cardiomyocyte hypertrophy, an increased expression of TGF-β1 and procollagen, and increased connective tissue in the LV. Associated with these results, it was indicated the involvement of the cardiac renin-angiotensin system in the remodeling process. However, even though all these changes have occurred in both treated groups, only the group receiving concurrent radiation and chemotherapy had a decrease in the cardiac function, showed by echocardiography. It is suggested that the combination of these therapies to the heart is more detrimental than the irradiation applied alone. The aims of this work were achieved, and it is possible to better understand the pathways involved in cardiotoxicity. This is a novel study, the subject issue is recent, and of high impact in the development of new treatment strategies for BC where the involved cardiac complications are considered.
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Papel do Sistema Renina-Angiotensina (SRA) na hipertrofia cardíaca induzida por lesão renal isquêmicaAbrahão, Mariana Vieira January 2015 (has links)
Orientadora: Profa. Dra.Marcela Sorelli Carneiro Ramos / Tese (doutorado) - Universidade Federal do ABC, Programa de Pós-Graduação em Biossistemas, 2015. / Recentemente, dados na literatura demonstram a estreita interacao patofisiologica existente entre os rins e o coracao. Conhecida como sindrome cardio-renal, essa patologia e capaz de promover hipertrofia e falencia cardiaca a partir de um quadro de lesao renal. Sabe-se que a lesao renal isquemica (LRI) promove a liberacao de diferentes citocinas inflamatorias que tem o coracao como tecido alvo e sao capazes de promover a instalacao do quadro hipertrofico, agindo, por exemplo, por meio de receptores semelhantes ao Toll (toll-like receptors - TLR). Alem de mediadores inflamatorios, trabalhos presentes na literatura ja comprovaram a direta relacao entre alteracoes no sistema renina-angiotensina (SRA) e nos niveis de Angiotensina II (Ang II) com o aumento da massa cardiaca. O presente estudo objetivou investigar o papel do SRA com a hipertrofia cardiaca (HC) induzida por um modelo experimental de LRI em camundongos tratados ou nao com bloqueadores do SRA, Losartan (Los) e Enalapril (Ena). O quadro de LRI foi induzido cirurgicamente atraves da oclusao do pediculo renal esquerdo por 60 minutos seguido de reperfusao. Apos 12, 15 ou 20 dias os tecidos foram removidos para a realizacao de analises macromorfometricas, moleculares e funcionais. Os principais resultados indicam que a cirurgia de isquemia renal e reperfusao foi capaz de gerar um quadro de falencia renal e induzir HC de maneira independente de aumento na pressao arterial. Ainda, no periodo analisado, observou-se aumento nos niveis sericos de TNF-¿¿ e Ang II, elevados niveis de expressao genica ou proteica de AT1, ECA-2, TLR-2, TLR-4 e NFk¿À, sugerindo relacao
desses componentes com a HC. Os tratamentos com Los e Ena reverteram completamente a HC observada e aboliram o aumento na expressao cardiaca de TLRs, AT1R e ECA-2 e modularam diferencialmente os niveis sericos de Ang II e citocinas inflamatorias. Juntos, os dados sugerem um papel crucial do SRA na regulacao do quadro patologico neste modelo,
atuando juntamente com o sistema imune inato na regulacao da patogenese da HC atraves da modulacao de seus principais componentes. / Recently published data demonstrate the close pathophysiological interaction
between the kidneys and the heart. Known as cardio-renal syndrome, this
pathology is capable of promoting hypertrophy and heart failure starting from
renal injury. It is known that ischemic renal injury (IRI) promotes the release
of various inflammatory cytokines that have the heart as a target tissue and
are capable of promoting hypertrophy acting through the Toll-like receptors
(TLR). In addition to inflammatory mediators, literature has extensively
demonstrated the direct correlation between changes in the renin-angiotensin
system (RAS) and the levels of angiotensin II (Ang II) within the increase in
cardiac mass. This study aimed to investigate the role of the RAS with
cardiac hypertrophy (CH) induced by an experimental model of IRI in mice
treated or not with RAS blockers, Losartan (Los) and Enalapril (Ena). The IRI
was surgically induced by occlusion of the left renal pedicle for 60 minutes
followed by reperfusion. After 12, 15 or 20 days, tissues were removed and
morphological, molecular, and functional analysis were performed. The
leading results indicate that renal ischemia and reperfusion surgery was
capable of generating renal failure which subsequently induced HC in a
blood-pressure independent manner. Also, over this period, there was an
increase in serum levels of TNF-á and Ang II, high levels of gene or protein
expression of AT1, ACE-2, TLR-2, TLR-4 and NFkâ, suggesting a cross-talk
within these components and CH development. Treatment with Los or Ena
has completely reversed the CH and abolished the increase observed in
cardiac expression of TLRs, NFkâ, ACE-2 and AT1R, and also differentially
modulated Ang II and inflammatory cytokines serum levels. Together, the
data suggest a critical role for RAS in the regulation of the pathological
condition in this model, acting together with the innate immune system in the
pathogenesis of CH through modulation of its main components.
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Reparo ósseo peri-implantar em tíbias de ratos espontaneamente hipertensos (SHR) tratados com losartan: análise biomecânica, molecular, microtomográfica, dinâmica óssea por fluorocromos, imunoistoquímica e histológica / Peri-implant bone healing in the tibia of spontaneously hypertensive rats (SHR) treated with losartan: a biomechanical, molecular, microtomography, bone dynamics by fluorochromes, immunohistochemical and histological analysisSantos, Gabriel Mulinari dos [UNESP] 09 February 2018 (has links)
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Previous issue date: 2018-02-09 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Introdução: A hipertensão está associada a doenças cardiovasculares, mas também com
alterações na qualidade óssea. A hipertensão, portanto, pode ser um fator de risco para a
osseointegração. Estudos pré-clínicos sugerem que o losartan, um bloqueador dos receptores
da angiotensina II amplamente utilizado para tratar a hipertensão, tem um efeito benéfico na
consolidação do enxerto. No entanto, o efeito da hipertensão e do losartan na osteointegração
permanece desconhecido.
Material e Métodos: Aqui utilizamos ratos ratas espontaneamente hipertensivos (SHR) e ratos
Wistar albinus normotensos que receberam losartan (30 mg / kg, p.o.) ou não tratados. Após
uma semana, mini-implantes de titânio foram inseridos na tíbia. Sessenta dias após a
implantação, a estabilidade do implante foi avaliada pela medição de torque de remoção
considerada o ponto final primário. A tomografia computadorizada micro e a análise
histomorfométrica foram parâmetros secundários.
Resultados: o Losartan aumentou o torque de remoção no grupo SHR hipertenso para os níveis
dos controles Wistar. Enquanto os parâmetros corticais da osseointegração permaneceram
inalterados, losartan aumentaram a formação do osso medular. A micro tomografia
computorizada revelou maior volume ósseo por volume de tecido e espessura trabecular nos
ratos SHR tratados com losartan. A análise histomorfométrica mostrou ainda que o losartan
aumentou significativamente a espessura do osso recém-formado na área medular em ratos
SHR hipertensos. O losartan não alterou significativamente os parâmetros de osseointegração
em ratos normotensos.
Conclusões: Os dados apresentados sugerem que o antagonista dos receptores da
angiotensina II losartan aumenta os parâmetros medulares da osseointegração no modelo da
tíbia de ratos espontaneamente hipertensos. / Background: Hypertension is associated with cardiovascular diseases but also with alterations in bone
quality. Hypertension therefore might be a risk factor for osseointegration. Preclinical studies suggest
that losartan, an angiotensin II receptor blocker widely used to treat hypertension, has a beneficial
effect in graft consolidation. However, the effect of hypertension and losartan on osseointegration
remains unknown.
Methods: Here we used spontaneously hypertensive rats (SHR) and normotensive Wistar albinus rats
receiving losartan (30 mg/kg, p.o.) or left untreated. After one week, titanium miniscrews were inserted
into the tibia. Sixty days after implantation, implant stability was evaluated by removal torque
measurement considered the primary endpoint. Micro computed tomography and histomorphometric
analysis were secondary endpoints.
Results: Losartan increased the removal torque in the hypertensive SHR group to levels of the Wistar
controls. While the cortical parameters of osseointegration remained unchanged, losartan increased
medullary bone formation. Micro computed tomography revealed a higher bone volume per tissue
volume and trabecular thickness in the SHR rats treated with losartan. Histomorphometric analysis
further showed that losartan significantly increased the thickness of newly formed bone in medullary
area in hypertensive SHR rats. Losartan did not significantly alter the parameters of osseointegration in
normotensive rats.
Conclusions: The data presented suggest that the angiotensin II receptor antagonist losartan increases
the medullary parameters of osseointegration in a tibia model of spontaneously hypertensive rats. / 16/03245-2
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Ação concomitante da irradiação e quimioterapia no coração de ratas Wistar / Concurrent Action of Irradiation and Chemotherapy at Wistar Rats HeartsCamila Salata 15 July 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O Câncer de mama (CM) é hoje o tipo de câncer mais incidente entre as mulheres, com a estimativa de 53 mil novos casos para o ano de 2013, segundo o Instituto Nacional do Câncer (INCA). É considerada uma doença de bom prognóstico, principalmente quando diagnosticada na sua fase mais precoce. A evolução no diagnóstico, e nas técnicas de tratamento para o CM, que incluem a quimioterapia e/ou radioterapia, aumentaram a expectativa de sobrevida para este tipo de câncer. Uma das complicações tardias induzidas pelo tratamento desta doença é a cardiotoxicidade. O termo cardiotoxicidade abrange uma série de efeitos colaterais, que incluem arritmias, alterações na pressão arterial, isquemia do miocárdio, trombose ou insuficiência cardíaca. É, por isso, fundamental entender os mecanismos envolvidos no desenvolvimento da toxicidade cardíaca para o sucesso do tratamento dos pacientes com CM. Este trabalho teve como objetivo avaliar os efeitos cardíacos tardios induzidos pela irradiação e quimioterapia, simulando um tratamento para o CM, em ratas Wistar. Ratas Wistar, com aproximadamente 3 meses de idade, foram divididas em: grupo controle, grupo que recebeu quimioterapia + irradiação (TC+IR), e grupo que recebeu apenas irradiação (IR). A quimioterapia foi administrada em 4 ciclos, com intervalo de 1 semana entre eles. A irradiação na região do coração foi realizada em dose única, de 20Gy, em um campo de 2x2 cm2. Os ratos foram submetidos à eutanásia 5 meses após o término dos tratamentos, para que os efeitos tardios pudessem ser avaliados. Vários estudos foram conduzidos: ecocardiografia para observar as alterações funcionais do coração; PCR em tempo real para detectar alterações no nível mRNA de procolágeno tipo I, TGF-β1, angiotensinogênio, renina, ECA, AT1, VEGF e razão Bax/;bcl2, no tecido do ventrículo esquerdo (VE); Além de ensaios histológicos para avaliar o aspecto do tecido cardíaco do VE. Resultados e discussão Os resultados obtidos indicam um processo de remodelamento cardíaco após os tratamentos para o CM. Sugere-se que este remodelamento inicie-se com a diminuição de vasos no VE, causada pelos tratamentos, conforme os resultados da estereologia e do PCR para VEGF. Em seguida mostrou-se hipertrofia dos cardiomiócitos, o aumento da expressão de procolágeno e TGF-β1 e de tecido conjuntivo neste tecido. E associado a estes resultados, mostrou-se a participação dos sistema renina angiotensina cardíaco neste processo de remodelamento. Porém, apesar de todas estas alterações terem ocorrido em ambos os grupos tratados, apenas o grupo que recebeu irradiação e quimioterapia concomitantemente apresentou alteração da função cardíaca, na ecocardiografia. Sugere-se, desta forma, que a associação destas terapias seja mais lesiva ao coração, do que a irradiação aplicada exclusivamente. Conclusão Os objetivos do trabalho foram alcançados, e pode-se entender melhor as vias envolvidas na cardiotoxicidade. Este é um estudo inédito, o assunto abordado é recente, e de sumo importância para o desenvolvimento de novas estratégias de tratamento para o CM, onde sejam consideradas as complicações cardíacas tardias envolvidas. / Breast cancer (BC) is today the most frequent type of cancer among women, there were estimated 53 000 new cases for the year 2013, according to the National Cancer Institute (INCA). It is considered a disease of good prognosis, especially when diagnosed in early stages. The developments in the diagnosis, and treatment techniques for the BC, which include chemotherapy and/or radiotherapy, increased the survival rates for this type of cancer. One late complication induced by BC treatment is the cardiotoxicity. The cardiotoxicity term comprises different cardiotoxic side effects, which includes arrhythmia, blood pressure alterations, myocardial ischemia, thrombosis or congestive heart failure. It is, therefore, essential to understand the mechanisms involved in the development of cardiac toxicity for the successful treatment of patients with BC. This study aimed to evaluate the late cardiac effects induced by irradiation and chemotherapy, simulating a treatment for BC in Wistar rats. Wistar rats, about 3 months old, were divided into control group; a group receiving chemotherapy + irradiation (TC+IR), and a group that received only irradiation (IR). Chemotherapy was administered in 4 cycles, with an one week interval between them. The irradiation at the heart area was performed in a single dose of 20 Gy, and a field of 2x2 cm2. The rats were euthanized 5 months after the end of treatments, so the late effects could be evaluated. Several studies were conducted: echocardiography to observe the heart functional changes, real-time PCR to detect alterations in mRNA level of procollagen type I, TGF-β1, angiotensinogen, renin, ACE, AT1, VEGF and Bax/bcl2 ratio, in the left ventricle (LV) tissue; The LV cardiac tissue was also evaluated by assays. The results indicate a process of cardiac remodeling after the BC. It is suggested that this remodeling starts with a reduction of the cardiac vessels, induced by treatments, according the results of stereology, and the PCR for VEGF. Then, it was showed a cardiomyocyte hypertrophy, an increased expression of TGF-β1 and procollagen, and increased connective tissue in the LV. Associated with these results, it was indicated the involvement of the cardiac renin-angiotensin system in the remodeling process. However, even though all these changes have occurred in both treated groups, only the group receiving concurrent radiation and chemotherapy had a decrease in the cardiac function, showed by echocardiography. It is suggested that the combination of these therapies to the heart is more detrimental than the irradiation applied alone. The aims of this work were achieved, and it is possible to better understand the pathways involved in cardiotoxicity. This is a novel study, the subject issue is recent, and of high impact in the development of new treatment strategies for BC where the involved cardiac complications are considered.
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