L’obésité est devenue un véritable problème de santé publique. Elle est fréquemment associée à plusieurs anomalies cardiométaboliques telles que l’hypertension artérielle, l’insulinorésistance et les dyslipidémies qui font le lit du diabète de type 2 et des maladies cardiovasculaires. Cependant la fréquence de ces anomalies varie considérablement parmi les sujets obèses faisant de cette maladie chronique une situation clinique très hétérogène. A ce titre un nouveau concept a émergé, impliquant une population de patients sans facteurs de risque apparents, appelé « obèse métaboliquement sain » ou « metabolically healthy obese » (MHO). Des efforts sont en cours pour comprendre les mécanismes sous-jacents à ce phénotype et ses conséquences à long terme. L’objectif principal de cette thèse était d’étudier le lien entre le phénotype MHO et diverses pathologies chroniques connues pour être associées à l’obésité. Les données provenant des cohortes Whitehall II et GAZEL ont été utilisées pour examiner les associations entre le phénotype MHO et la mortalité, les maladies cardiovasculaires, le diabète de type 2 et la dépression. En comparaison aux sujets de poids normal métaboliquement sains, les individus MHO ont un risque accru de mortalité globale et cardiovasculaire, de diabète de type 2 et de maladies cardiovasculaires mais pas de dépression. Comparés aux sujets obèses avec anomalies métaboliques, les individus MHO ont un risque similaire de mortalité et de maladies cardiovasculaires, mais un moindre risque de diabète de type 2 et dépression. Nos résultats suggèrent que l’obésité à profil cardiométabolique normal n’est pas une condition bénigne. Une meilleure compréhension de ce phénotype contribuera à améliorer la décision thérapeutique et aidera peut-être à identifier des cibles thérapeutiques nouvelles. / Obesity has become a major public health concern. It is frequently associated with several cardiometabolic abnormalities such as hypertension, insulin resistance and dyslipidemia leading to type 2 diabetes and cardiovascular disease. However, the frequency of these abnormalities varies widely among obese subjects, making this chronic condition a very heterogeneous clinical situation. As such a new concept has emerged, involving a population of patients without metabolic risk, called "metabolically healthy obese" (MHO). Intense interest surrounds the MHO phenotype with on-going efforts to understand the mechanisms underlying this phenotype and its long-term consequences. The main objective of this thesis was to study the relationship between the MHO phenotype and various chronic diseases known to be associated with obesity. Data from the Whitehall II and GAZEL cohorts were used to examine associations between this phenotype and mortality, cardiovascular diseases, type 2 diabetes, and depression. Compared to metabolically healthy normal weight subjects, MHO individuals have an increased risk of overall and cardiovascular mortality, type 2 diabetes and cardiovascular diseases, but not depression. Compared to metabolically unhealthy obese subjects, MHO individuals have a similar risk of mortality and cardiovascular disease, but a lower risk of type 2 diabetes, and depression. Our results suggest that obesity with normal cardiometabolic profile is not a benign condition. A better understanding of this phenotype will enhance therapeutic decision making and possibly help to identify new therapeutic targets.

Le diabète de type 2 (DT2) est une maladie chronique associée à de graves et coûteuses complications. Dans un contexte de restriction budgétaire, il est nécessaire de pouvoir estimer les ressources à affecter à la prise en charge des maladies chroniques et donc de suivre l’évolution épidémiologique et économique d’une telle maladie. Une base de données a été construite à partir des données médico-administratives de l’assurance maladie luxembourgeoise. Elle comprenait les consommations de soins, associées au diabète et ses complications, des patients diabétiques de type 2 traités entre 2000 et 2006. L’objectif était d’étudier les champs d’utilisation de ces données et leurs applications possibles pour les décisions en santé publique. Cette thèse en donne quelques exemples. En 2006, la prévalence du DT2 au Luxembourg était de 3,79% (N= 17 070). Un algorithme a permis d’identifier trois stades de la néphropathie diabétique (3,77% des cas de DT2 en 2006). L’analyse de l’adhérence aux recommandations européennes de bonnes pratiques médicales a mis en évidence une situation critique associée à certains facteurs (médecin traitant, type de traitement, région de résidence…). Les dépenses moyennes d’un patient en hémodialyse a été estimé à 116 647€/patient en 2006. Enfin, une analyse médico-économique a montré la dominance coût-efficace d’une stratégie d’implémentation de la dialyse péritonéale sur la situation actuelle. Malgré les difficultés à évaluer leur qualité, les données médico-administratives offrent une source d’informations précieuses pour les décideurs publics et les professionnels de la santé, dans le but d’améliorer la prise en charge des patients. / Type 2 diabetes (T2D) is a chronic disease associated with many severe and costly complications. In a context of budgetary constraint, it is necessary to obtain an estimate the amount of resources to allocate to the management of chronic diseases. This includes monitoring the epidemiologic and economic evolutions. A database was built from medico-administrative databases of the national health insurance of Luxembourg. It included the healthcare consumptions associated with diabetes and its complications, of all type 2 diabetic patients treated in Luxembourg between 2000 and 2006. The objectives were to study the fields of use of this database and the possible applications for public health decision-making. This thesis gives some examples. In 2006, T2D prevalence in Luxembourg was 3.79% (N= 17070). An algorithm was built and permitted to identify three stages of diabetic nephropathy (3.77% of T2D cases in 2006). The analysis of the adherence to European follow-up guidelines showed a critical situation associated to several factors (treating physician, type of treatment, living region…). The mean costs associated with patients in dialysis were estimated at 116 647€/patient in 2006. Finally, a health-economic evaluation showed the dominance of a strategy promoting peritoneal dialysis in Luxembourg over the present situation.

Diabetes mellitus tipo 2 (DM2) está associado a um estado de inflamação crônica e ativação do estresse do retículo endoplasmático (ERE). Nesse contexto, são necessários estudos para encontrar alternativas que melhorem o quadro inflamatório, como os ácidos graxos poli-insaturados ômega 3 (n-3 PUFA), um conhecido agente anti-inflamatório. Esse estudo teve por objetivo avaliar o efeito da suplementação do ácido alfa-linolênico (ALA, um n-3 PUFA) no estresse do retículo endoplasmático e no estado inflamatório no tecido adiposo subcutâneo abdominal (TASC) em pacientes com DM2. Foi conduzido um estudo duplo-cego, prospectivo, placebo-controlado. Vinte pacientes com DM2 foram randomizados para suplementação com 3g/dia de ALA ou placebo durante 60 dias. O tecido adiposo foi coletado através de punção aspirativa por agulha fina do abdome antes e após a suplementação e os genes e proteínas foram avaliados através de PCR em tempo real e western blot. Foi encontrada, após suplementação, uma redução da expressão gênica do XBP1 (20%), sXBP1 (70%) e aumento da expressão gênica do GRP78 (150%), confirmado na expressão proteica. Além disso, foi encontrado aumento da expressão gênica da adiponectina (90%) e redução da expressão gênica do IL-6 (80%) e IRS-1 (60%), sem correlação com a expressão proteica, no tempo pós-suplementação com ALA. Portanto, foi demonstrado que o ALA pode modular o ERE através da via da IRE1/XBP, levando ao aumento das chaperonas (BIP/GRP78), além de um efeito adicional na expressão gênica da adiponectina, IL-6 e IRS-1, o que pode demonstrar um potencial terapêutico do ALA em pacientes com DM2. / Type 2 diabetes mellitus (T2DM) is a state of chronic inflammation and activation of endoplasmic reticulum stress (ERS). In this context, studies are necessaries to find new possibilities to improve this inflammation such as the n-3 polyunsaturated fatty acid (n-3 PUFA) acting as an anti-inflammatory agent. In this study, we aimed to evaluate the effect of n-3 PUFA alpha-linolenic acid (ALA, a n-3 PUFA) supplementation in T2DM patients on the molecular expression of ERS genes in abdominal subcutaneous adipose tissue (SAT). We performed a placebo-controlled study, in a double-blind design with 20 T2DM patients, receiving, randomly, 3g/day of ALA or placebo for 60 days. The adipose tissue was collected by fine-needle aspiration in abdomen before and after the supplementation and the genes and proteins were evaluated by real-time PCR and western blot. It was seen, after the supplementation, a reduction in XBP1 (20%), sXBP1 (70%) and an increase in Grp78 (150%) gene expression, likewise same results in protein concentration. Furthermore, it was observed an increase in adiponectina (90%) gene expression and reduction in IL-6 (80%) and IRS-1 (60%) gene expression, with no correlation to protein expression after supplementation of ALA. Therefore, we have provided evidence that ALA may modulate ERS by the IRE1/XBP pathway leading to an increase in chaperones (BIP/GRP78), additionally its effect on adiponectina, IL-6 and IRS-1 gene expression can demonstrate a therapeutic potential in T2DM.

L’insuline et la sérotonine (5-HT) sont deux acteurs majeurs du maintien de l’homéostasie énergétique, fonction placée sous le contrôle de l’hypothalamus. En ciblant cette région, l’insuline remplit de nombreuses fonctions métaboliques via l’activation de la voie PI3K/Akt. La 5-HT exercent des effets biologiques similaires mais les voies de signalisation impliquées dans ces processus étaient jusqu’alors mal connues. De plus, il avait été démontré que la 5-HT est capable d’activer la voie PI3K/Akt/GSK3β dans l’hippocampe, mécanisme sous-tendant potentiellement les effets antidépresseurs du neurotransmetteur. Les principaux objectifs de cette thèse étaient d’étudier 1/ l’activation de la voie PI3K/Akt par la 5-HT dans l’hypothalamus de rats diabétiques (modèle Goto-Kakizaki) et chercher un potentiel dialogue avec l’insuline and 2/ les mécanismes sous-tendant l’induction de la dépression par une alimentation hyperlipidique, par l’analyse de la phosphorylation d’Akt et GSK3β sous l’action de l’insuline, de la leptine et de la 5-HT dans l’hippocampe de rat.Ici on montre que 1/ la 5-HT stimule la voie PI3K/Akt dans l’hypothalamus et que la phosphorylation d’Akt induite par la 5-HT est atténuée dans des conditions d’insulino-résistance, suggérant l’existence d’un dialogue entre les voies de signalisation de l’insuline et de la 5-HT. Par ailleurs, nos résultats indiquent qu’une alimentation hyperlipidique induit un comportement dépressif réversible chez le rat, qui pourrait impliquer la voie PI3K/Akt/GSK3β dans les neurones subgranulaires du gyrus denté. La mise en évidence d’un dialogue entre les voies de signalisation de la 5-HT, de la leptine et de l’insuline au niveau central enrichit nos connaissances sur le rôle de ces facteurs dans la régulation de l’homéostasie énergétique et de l’humeur, et propose un lien moléculaire entre diabète de type 2, obésité et dépression / Insulin and serotonin (5-HT) are two key players in the maintenance of energy homeostasis which is controlled by the hypothalamus. In this brain region, insulin mediates numerous metabolic effects via the activation of the PI3K/Akt signaling pathway. 5-HT exerts similar biological properties by acting in the hypothalamus but the signaling pathways accountable for these effects are still unclear. Moreover, it has been reported that 5-HT induces the activation of the PI3K/Akt pathway in the hippocampus and the inhibition of GSK3β, suggesting this action as a potential mechanism for the antidepressant effects of this neurotransmitter.The main objectives of this thesis were to study 1/ the serotonin-induced activation of the PI3K/Akt in the hypothalamus of wild type and diabetic rats (Goto-Kakizaki model) and search a potential cross-talk with insulin and, 2/ the mechanisms underlying the high-fat diet induced depression by investigating the role of the phosphorylation of Akt and GSK3β by 5-HT, insulin and leptin in the hippocampus of rats.Here, we show that 5-HT triggers the PI3K/Akt signaling pathway in the rat hypothalamus, and that this activation is attenuated in insulin-resistant conditions, suggesting a cross-talk between insulin and 5-HT. Moreover, we reported that high-fat diet feeding induces a reversible depressive-like behavior, which may involve the PI3K/Akt/GSK3β pathway in subgranular neurons of the dentate gyrus. In conclusion, the activation of the PI3K/Akt pathway and its target GSK3β by 5-HT in the hypothalamus and in the dentate gyrus, respectively, can be impaired in insulin-/leptin-resistant states, which may underlie a link between metabolic diseases and depression.

Made available in DSpace on 2014-06-11T19:30:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-25Bitstream added on 2014-06-13T21:01:31Z : No. of bitstreams: 1 fernandes_ra_dr_rcla.pdf: 1297724 bytes, checksum: 896dd66dcf9341e251f414b66fbe846a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Introdução: A prevalência da prática regular de atividades físicas na população adulta brasileira ainda é desconhecida, principalmente em cidades do interior dificultando assim a elaboração de campanhas efetivas na promoção de sua prática. Objetivo: Portanto, o objetivo deste trabalho foi analisar, em adultos de ambos os sexos no Estado de São Paulo, a prevalência da prática regular de atividades físicas e suas associações com as doenças cardio-metabólicas. Métodos: Por meio de amostragem aleatória em diferentes estágios, uma amostra de 2720 adultos (idade > 18 anos) foi selecionada em oito cidades do Estado de São Paulo. As entrevistas foram feitas nos domicílios dos entrevistados através de questionários sobre: (i) Atividade física atual no lazer (fisicamente ativo se ≥180min/sem de atividades moderadas ou vigorosas a mais de 4 meses); (ii) Barreiras pessoais; (iii) Atividade física na infância e adolescência; (iv) Doenças e excesso de peso; (v) Informações gerais (sexo, escolaridade e idade). O teste qui-quadrado analisou associações entre os dados categóricos e a regressão logística analisou a magnitude das mesmas. Resultados: No lazer, homens foram mais ativos do que as mulheres (p= 0,001), bem como, grupos com maior escolaridade (p= 0,007) e menor idade (p= 0,002) foram mais ativos. Moradores da capital foram menos ativos do que moradores do litoral e interior do estado (p= 0,001). Tanto na capital, como no interior e litoral, quanto maior o número de barreiras pessoais, menor a prática de atividades no lazer (p= 0,001 para todos). Adultos que praticaram atividades esportivas na infância e adolescência apresentaram 1,6 vezes mais chances de serem ativos no lazer (p= 0,001). Além disso, indivíduos que foram ativos ao longo da vida apresentaram 45% (p= 0,013), 35% (p= 0,010) e 49% (p= 0,011) menos chance de relatar hipertensão arterial... / Background: Physical activity level in Brazilian adults is unknown, mainly in non-capital cities and this absence of data difficult the implementation of effective promotion programs. Objectives: To analyze, in adults of both genders living in Sao Paul State, the physical activity level and its associations with some diseases. Methods: A sample of 2720 adults has been selected in eight cities of the Sao Paulo State through a multistage random process. Questionnaires were applied through home interviews: (i) current physical activity (physically active: ≥180min/wk of either moderate or vigorous activities for at lest 4 months before the interview); (ii) Personal barriers; (iii) Early physical activity; (iv) Diseases and overweight; (v) general information (gender, schooling and age). Chi-square test analyzed associations among categorical data and logistic regression indicated the magnitude of it. Results: In leisure time, men were more physically active than women (p= 0.001), as well as, groups of higher schooling (p= 0.007) and lower age (p= 0.002). People living in Capital reported lower physical activity practice than those one from coast and non-capital cities (p= 0.001). In all cities, higher number of personal barriers was associated with lower leisure time physical activity (p= 0.001 for all). Adults engaged in sport activities during childhood and adolescence had 1.6 more likely to be active in leisure time (p= 0.001). Moreover, persons persistently active through life had 45% (p= 0.013), 35% (p= 0.010) and 49% (p= 0.011) less likely to report arterial hypertension, dyslipidemia and obesity, respectively. Area residents of places with higher number of public parks were more physically actives (p= 0.005), but not in the Capital (p= 0.982). Conclusions: physical activity level is higher in coast and non-capital cities, as well as, in the Capital there were more personal... (Complete abstract click electronic access below)

Orientador: Angelina Zanesco / Banca: Maria Claudia Costa Irigoyen / Banca: Katia de Angelis / Banca: Henrique Luiz Monteiro / Banca: Rodolfo Franco Puttini / Resumo: Introdução: A prevalência da prática regular de atividades físicas na população adulta brasileira ainda é desconhecida, principalmente em cidades do interior dificultando assim a elaboração de campanhas efetivas na promoção de sua prática. Objetivo: Portanto, o objetivo deste trabalho foi analisar, em adultos de ambos os sexos no Estado de São Paulo, a prevalência da prática regular de atividades físicas e suas associações com as doenças cardio-metabólicas. Métodos: Por meio de amostragem aleatória em diferentes estágios, uma amostra de 2720 adultos (idade > 18 anos) foi selecionada em oito cidades do Estado de São Paulo. As entrevistas foram feitas nos domicílios dos entrevistados através de questionários sobre: (i) Atividade física atual no lazer (fisicamente ativo se ≥180min/sem de atividades moderadas ou vigorosas a mais de 4 meses); (ii) Barreiras pessoais; (iii) Atividade física na infância e adolescência; (iv) Doenças e excesso de peso; (v) Informações gerais (sexo, escolaridade e idade). O teste qui-quadrado analisou associações entre os dados categóricos e a regressão logística analisou a magnitude das mesmas. Resultados: No lazer, homens foram mais ativos do que as mulheres (p= 0,001), bem como, grupos com maior escolaridade (p= 0,007) e menor idade (p= 0,002) foram mais ativos. Moradores da capital foram menos ativos do que moradores do litoral e interior do estado (p= 0,001). Tanto na capital, como no interior e litoral, quanto maior o número de barreiras pessoais, menor a prática de atividades no lazer (p= 0,001 para todos). Adultos que praticaram atividades esportivas na infância e adolescência apresentaram 1,6 vezes mais chances de serem ativos no lazer (p= 0,001). Além disso, indivíduos que foram ativos ao longo da vida apresentaram 45% (p= 0,013), 35% (p= 0,010) e 49% (p= 0,011) menos chance de relatar hipertensão arterial... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Background: Physical activity level in Brazilian adults is unknown, mainly in non-capital cities and this absence of data difficult the implementation of effective promotion programs. Objectives: To analyze, in adults of both genders living in Sao Paul State, the physical activity level and its associations with some diseases. Methods: A sample of 2720 adults has been selected in eight cities of the Sao Paulo State through a multistage random process. Questionnaires were applied through home interviews: (i) current physical activity (physically active: ≥180min/wk of either moderate or vigorous activities for at lest 4 months before the interview); (ii) Personal barriers; (iii) Early physical activity; (iv) Diseases and overweight; (v) general information (gender, schooling and age). Chi-square test analyzed associations among categorical data and logistic regression indicated the magnitude of it. Results: In leisure time, men were more physically active than women (p= 0.001), as well as, groups of higher schooling (p= 0.007) and lower age (p= 0.002). People living in Capital reported lower physical activity practice than those one from coast and non-capital cities (p= 0.001). In all cities, higher number of personal barriers was associated with lower leisure time physical activity (p= 0.001 for all). Adults engaged in sport activities during childhood and adolescence had 1.6 more likely to be active in leisure time (p= 0.001). Moreover, persons persistently active through life had 45% (p= 0.013), 35% (p= 0.010) and 49% (p= 0.011) less likely to report arterial hypertension, dyslipidemia and obesity, respectively. Area residents of places with higher number of public parks were more physically actives (p= 0.005), but not in the Capital (p= 0.982). Conclusions: physical activity level is higher in coast and non-capital cities, as well as, in the Capital there were more personal... (Complete abstract click electronic access below) / Doutor

Made available in DSpace on 2014-07-29T15:25:18Z (GMT). No. of bitstreams: 1 Tese Ana Clara M e S Carvalho - Patologia Clinica.pdf: 1557137 bytes, checksum: 899de7fc14fbe34def669ae52588c5f8 (MD5) Previous issue date: 2012-02-27 / Introduction: The dietary fiber, particularly soluble, are assigned the physiological effects that are important for the treatment of patients with type 2 diabetes mellitus. Objective: To evaluate the effect of supplementing wheat dextrin in insulin sensitivity, glycemic control and lipid, and nutritional status of patients with type 2 diabetes mellitus. Methodology: This is a trial blind, randomized, lasting 12 weeks.The sample consisted of 27 type 2 diabetic subjects of both sexes with a BMI ≥ 25.00 kg/m2 and sedentary. These subjects were randomized into two groups, test (n = 14) and placebo (n = 13). The test group was supplemented daily with 200 ml of orange flavor beverage without the addition of sugar and added 10 g of wheat dextrin, 30 minutes before the lunch. The control group received the same drink daily, but without the addition of fiber. Participants were instructed to maintain their lifestyle (diet and physical activity). Fasting plasma glucose, glycated hemoglobin (A1c), insulin sensitivity, lipid profile, the level of physical activity, intestinal function, food intake, and anthropometric indicators were assessed at baseline, 45 and 90 days intervention. Results: The A1c, fasting glucose and lipid profile showed no significant differences within and between groups. There was an increase in the values of HOMA-IR (p = 0.0163) and fasting insulin (p = 0.0406) at 45 days in the placebo group, with significant difference. The increase in HOMA-IR and fasting insulin resulted in decreased insulin sensitivity in the placebo group. In the test group showed no changes in insulin sensitivity. The test group showed improvement in bowel function. The fiber intake was below the recommendation for the diabetic.Food intake, body weight, BMI and waist circumference (WC) also showed no significant change. The percentage of body fat increased in the placebo group at 45 days (p = 0.0342) and decreased in the test group compared to placebo (p = 0.0216 and 0.0285). The basal metabolic rate (BMR) increased in the test group and decreased in placebo (p = 0.0198 and 0.005). Conclusion: Wheat dextrin in 10g/dia dosage did not improve insulin sensitivity, glycemic control and lipid, did not reduce body weight and WC and does not cause changes in the consumption of energy and macronutrients. There was increased consumption of fiber for the minimum of the recommendation, regulate bowel function, reduced body fat and increased the BMR. / Introdução: À fibra dietética, especialmente a fibra solúvel, são atribuídos efeitos fisiológicos que são importantes para o tratamento do paciente com diabetes mellitus tipo 2. Objetivo: Avaliar o efeito da suplementação de dextrina de trigo na sensibilidade à insulina, controle glicêmico e lipídico, e estado nutricional de portadores de diabetes mellitus tipo 2. Metodologia: Trata-se de um ensaio clínico cego, randomizado com duração de 12 semanas. A amostra foi composta por 27 indivíduos diabéticos tipo 2 de ambos os sexos, com IMC ≥ 25,00 kg/m2 e sedentários. Estes indivíduos foram randomizados em dois grupos, teste (n=14) e placebo (n=13). O grupo teste foi suplementado diariamente com 200 ml de bebida sabor laranja sem adição de açúcar e adicionada de 10 g de dextrina de trigo, 30 minutos antes do almoço. O grupo placebo recebeu diariamente a mesma bebida, mas sem adição de fibra. Os participantes foram orientados a manter seu estilo de vida (hábitos alimentares e de atividade física). A glicemia de jejum, a hemoglobina glicada (A1c), a sensibilidade à insulina, o perfil lipídico, o nível de atividade física, o funcionamento intestinal, o consumo alimentar, e os indicadores antropométricos foram avaliados no início, aos 45 e aos 90 dias de intervenção. Resultados: A A1c, a glicemia de jejum e o perfil lipídico não apresentaram diferenças significativas intra e entre grupos. Houve aumento nos valores de HOMA-IR (p=0,0163) e insulina de jejum (p=0,0406) aos 45 dias no grupo placebo, com diferença significativa. O aumento de HOMA-IR e insulina de jejum resultou em diminuição da sensibilidade à insulina do grupo placebo. No grupo teste não apresentou mudanças na sensibilidade à insulina. O grupo teste apresentou melhora no funcionamento intestinal. O consumo de fibras foi inferior a recomendação para o diabético. O consumo alimentar, o peso corporal, o IMC e a circunferência de cintura (CC) também não apresentaram mudanças significativas. A porcentagem de gordura corporal aumentou no grupo placebo aos 45 dias (p=0,0342) e diminuiu no grupo teste quando comparado ao grupo placebo (p=0,0216 e 0,0285). A Taxa de Metabolismo Basal (TMB) aumentou no grupo teste e diminuiu no placebo (p=0,0198 e 0,005). Conclusão: A dextrina de trigo na dosagem de 10g/dia não promoveu melhora na sensibilidade à insulina, no controle glicêmico e lipídico; não reduziu o peso corporal e CC e, não gerou mudanças no consumo de energia e de macronutrientes. Houve aumentou do consumo de fibra, para o mínimo da recomendação; regularização do funcionamento intestinal, redução da gordura corporal e aumento da TMB.

INTRODUÇÃO: O polimorfismo dentro do gene TCF7L2, rs7903146, é, até o momento, o marcador genético mais significantemente associado ao risco de diabetes mellitus tipo 2, sendo também associado à doença arterial coronariana. Contudo, pouco ainda se conhece sobre o papel funcional desse polimorfismo na patologia dessas doenças. O objetivo desse projeto foi investigar esse papel funcional, no fenótipo de células vasculares de músculo liso de 92 indivíduos, usando abordagens de comparação de níveis de expressão gênica e de comparação de correlações de expressão gênica, de modo que tais comparações fossem representadas visualmente como redes de interação gênica. MÉTODOS: Inicialmente, foram comparados os níveis de expressão de 41 genes (genes que possuem ou estão perto de variantes genéticas associadas ao diabetes mellitus tipo 2 e outros genes relacionados às vias de sinalização de diabetes mellitus tipo 2 ou às vias de proliferação celular) entre indivíduos com o alelo associado ao risco de diabetes mellitus tipo 2 (CT e TT) e indivíduos sem o alelo de risco (CC) do rs7903146. Com a finalidade de se observar se os genes estavam se relacionando de modo diferente entre os grupos genotípicos, foram comparados os padrões de correlação de expressão dos 41 genes. RESULTADOS: Quanto às comparações de níveis de expressão entre os grupos, cinco formas de splicing do gene TCF7L2 e os genes CDKAL1, IGF2BP2, JAZF1, CDKN2B, CAMK1D, JUN, CDK4, ATP2A2, e FKBP1A apresentaram níveis de expressão significativamente diferentes. Quanto às comparações de correlação de expressão entre os grupos, os genes RXR?, CALM1, CALR e IGF2BP2 foram os que mostraram os mais diferentes padrões de correlação com os outros genes. CONCLUSÃO: Deste modo, o alelo de risco analisado é apontado como tendo influência em cis na regulação da expressão de determinadas formas de splicing do gene TCF7L2 em células vasculares de músculo liso; além de parecer influenciar nas expressões e nas interações de genes relacionados à homeostase glicolítica e/ou proliferação celular. Sendo assim, através de nossas análises identificaram-se possíveis candidatos-alvos no tratamento de redução do risco em indivíduos com alto risco de desenvolvimento de diabetes mellitus tipo 2 e de doença arterial coronariana, especialmente os indivíduos que possuem os genótipos de risco analisados do gene TCF7L2 / INTRODUCTION: The SNP within the TCF7L2 gene, rs7903146, is, to date, the most significant genetic marker associated with type 2 diabetes mellitus risk, well as being associated with coronary artery disease. Nonetheless, its functional role in these diseases pathology is poorly understood. The aim of the present study was to investigate this role, in vascular smooth muscle cells from 92 patients undergoing aortocoronary bypass surgery, using expression levels and expression correlation comparison approaches, which were visually represented as gene interaction networks. METHODS: Initially, the expression levels of 41 genes (seven TCF7L2 splice forms and other 40 relevant genes) were compared between rs7903146 wild-type (CC) and type 2 diabetes mellitus risk (CT + TT) genotype groups. Next, the expression correlation patterns of the 41 genes were compared between genotypic groups in order to observe if the relationships between genes were different. RESULTS: Five TCF7L2 splice forms and CDKAL1, IGF2BP2, JAZF1, CDKN2B, CAMK1D, JUN, CDK4, ATP2A2 and FKBP1A genes showed significant expression differences between groups. RXR?, CALM1, CALR and IGF2BP2 genes were pinpointed as showing the most different expression correlation pattern with other genes. CONCLUSION: Therefore, type 2 diabetes mellitus risk alleles appear to be influencing TCF7L2 splice form\'s expression in vascular smooth muscle cells; besides it can be influencing expression and interactions of genes related to glucose homeostasis and/or cellular proliferation. Thereby, through our analysis were identified possible treatment target candidates for risk reduction in individuals with high-risk of developing type 2 diabetes mellitus and coronary artery disease, especially individuals harboring TCF7L2 risk genotypes

Le diabète de type 2 (DT2) est devenu de plus en plus une maladie métabolique chronique fréquente, associée à de nombreuses complications micro et macro-vasculaires. Les patients diabétiques ont environ deux fois plus de risque de mort subite d'origine cardiaque (MSC) que ceux normaux. Les interventions pharmacologiques (anti-plaquettaires, anti-hypertenseurs, anti-diabétiques et hypolépimiants) nous semblent les candidats les plus efficaces, accessibles et économiques pour prévenir cet événement à long terme, par contre leurs effets sur la MSC n'ont pas été bien connus. Nous visons à estimer leur impact sur la santé publique et à optimiser leur utilisation chez les DT2, grâce à des études d'analyse, de synthèse et de modélisation.Ce travail inclut trois étapes: premièrement, de construire un score de risque permettant de prédire le risque de MSC dans le DT2 en utilisant les bases de données INDANA. Deuxièmement, d'effectuer des méta-analyses/revues systématiques de différentes stratégies thérapeutiques afin d'estimer leurs effets sur le risque de MSC. Enfin, de simuler différentes stratégies sur une population virtuelle réaliste (PVR) des diabétiques français et d'intégrés les résultats obtenus sur cette plate-forme pour estimer le risque de MSC avec et sans traitements. Cette simulation permet d'estimer leurs bénéfices absolus, par le nombre d'événements prévus (Number of Events Prevented, NEP) et le nombre de patients à traiter pour prévenir une MSC (Number Needed to Treat, NNT). Nous avons construit un score incluant 7 facteurs de risque de MSC chez les patients atteints d'hypertension artérielle (+/- diabète) et collecté les meilleures estimations sur l'effet des médicaments. Notre simulation sur la PVR générée a suggéré que chez 10% des patients ayant le risque de MSC prédit le plus haut, la co-prescription de l'inhibiteurs de l'enzyme de conversion-l'aspirine-l'empagliflozine permettait de prévenir une MSC sur 57 individus traités dans les 5 ans. Le chiffre correspondant pour toute la PVR était 135. Nous concluons que cette approche pourrait aider à mieux transposer les résultats des essais cliniques à la pratique ; et à faciliter la décision clinique aux niveaux populationnel et individuel / Type 2 diabetes (T2D) has increasingly become a common metabolic condition, associated with numerous micro and macro-vascular complications. Diabetic patients are at about two-time higher risk of sudden cardiac death (SCD), compared to non-diabetic ones. Pharmacologic intervention (anti-platelet, anti-hypertensive, lipid lowering, and to a lesser extent, anti-diabetic agents) appear to be the most efficient and economic candidate to prevent this event at long term, yet treatment effects have not well addressed. We aimed to optimize their use and estimate their impact on public health via analysis, synthesis and modeling studies.This work engaged three phases: First, to construct a risk score to predict SCD risk in T2D from the INDANA database. Second, to perform the meta-analyses/systematic reviews of different therapeutic strategies in order to estimate their effects on SCD risk. Finally, to simulate therapeutic strategies on a generated French diabetic realistic virtual population (RVP) of T2D, by estimating the occurrence of SCD with and without treatments, thus their absolute benefits, through the Number of Events Prevented (NEP) due to treatment, and the Number of patients Needed to be Treated to prevent one SCD (NNT).We built a 7-risk factor to predict 5-year risk of SCD in patients with hypertension (+/-diabetes) and collected the best evidence on drugs’ effects. Integrating and simulating altogether on a generated French diabetic RVP suggested that for every 57 individuals of the 10% highest predicted SCD risk, the co-prescription of angiotensin converting enzyme inhibitor-aspirin-empagliflozin could prevent one SCD in 5 years. For the whole population, the corresponding number was 135. In perspectives, this approach could help better transposing clinical trial results into practice and facilitating clinical decision at both public health and individual levels

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