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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Estudo de variantes da leptina do receptor de leptina: impacto sobre as características relacionadas com a obesidade / Study of the leptin and the leptin receptor gene variants: impact on characteristics related with obesity

Oliveira, Raquel de 17 June 2008 (has links)
Neste estudo, foi avaliada a relação entre polimorfismos dos genes da leptina (LEP) e receptores da leptina (LEPR) e parâmetros antropométricos, leptinemia glicemia e lipídeos séricos, em indivíduos da população brasileira. Foram incluídos 238 indivíduos com idade entre 30 e 80 anos. Foram medidos o índice de massa corporal (IMC), a cintura abdominal (CA) e a razão cintura quadril (RCQ). Amostras de sangue periférico foram obtidas para análise do perfil bioquímico e extração de DNA. Os polimorfismos de nuleotideo único (SNPs) LEP G-2548A e LEPR Lys109Arg, Gln223Arg e Lys656Asn foram detectados por PCR-RFLP. Os SNPs LEPR Lys109Arg e Gln223Arg foram associados com obesidade e com IMC e CA aumentados (p<0.05). Estes polimorfismos também foram associados com leptina e glicose elevada (p<0,05). O perfil lipídico sérico foi influenciado pelo polimorfismo LEPR Lys109Arg (p<0.05). A relação entre os SNPs LEPR Lys109Arg e Gln223Arg e o perfil lipídico foi modificada pelo gênero. Os haplótipos LEP G-2548/ LEPR Lys109Arg foram relacionados com diferenças no IMC de obesos. Os haplotipos LEPR Lys109Arg/Gln223Arg foram associados com diferenças na CA e glicemia e lipídeos séricos. Em conclusão, os polimorfismos LEPR Lys109Arg e Gln223Arg estão associados com obesidade e alterações de leptina, glicose e lipídeos circulantes de forma dependente do gênero. / We have assessed the relationship between polymorphisms of the leptin (LEP) and the leptin receptor (LEPR) genes and anthropometric parameters, plasma leptin and glucose and serum lipids in individuals of the Brazilian population. We included 238 individuais with 30 to 80 years. Body mass index (BMI), abdominal circumference (AC) and waist-to-hip ratio (WHR) were measured. Peripheral blood samples were collected for analysis of the biochemical profile and DNA extraction. The single nucleotide polymorphisms (SNP) LEP G-2548A and LEPR Lys109Arg, Gln223Arg and Lys656Asn were detected by PCR-RFLP. The SNPs LEPR Lys109Arg and Gln223Arg were associated with obesity and with increased BMI and AC (p <0.05). These polymorphisms were also associated with increase leptin and glucose (p<0,05). The serum lipid profile was influenced by the LEPR Lys 1 09Arg (p<0.05). The relationship between the SNPs LEPR Lys 1 09Arg and Gln223Arg and the lipid profile was modified by gender. The haplotypes LEP G-2548A1 LEPR Lys109Arg were related with differences on BMI in obese group. The haplotypes LEPR Lys109Arg/Gln223Arg were associated with differences on AC, glucose and serum lipids. In conclusion, the LEPR Lys109Arg and Gln223Arg polymorphisms are associated with obesity and alterations in blood leptin, glucose and lipids in a gender-dependent manner.
162

Prática da atividade física e a prevalência de doenças cardio-metabólicas no estado de São Paulo

Fernandes, Rômulo Araújo [UNESP] 25 February 2011 (has links) (PDF)
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)
163

Prática da atividade física e a prevalência de doenças cardio-metabólicas no estado de São Paulo /

Fernandes, Rômulo Araújo. January 2011 (has links)
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
164

The Diabetes Risk Assessment study: Elucidating the inflammatory profile of the Metabolically Healthy Obese

Perreault, Maude 27 August 2013 (has links)
This thesis investigates the complexity of the obesity phenotype by characterizing the inflammatory status of Metabolically Healthy Obese (MHO) individuals. More specifically, this work has examined circulating inflammatory markers in MHO individuals and compared it to Lean Healthy (LH) and Metabolically Abnormal Obese (MAO) subjects. Thirty participants (n=10/group) were recruited as part of the Diabetes Risk Assessment (DRA) study, and classified according to adiposity and metabolic status. Despite a similar level of adiposity compared to MAO individuals, MHO subjects presented a more favourable inflammatory profile. Specifically, MHO individuals had levels of hsCRP and IL-6 comparable to LH subjects and lower than MAO subjects. Also, MHO subjects presented similar levels of high molecular weight adiponectin as the MAO group, but PDGF-ββ levels were intermediate to those of the LH and MAO groups. Overall, the distinct inflammatory profile observed in MHO subjects demonstrates the unique status of these individuals, reinforcing that obesity is a complex and heterogeneous phenotype. / Public Health Agency of Canada, Ontario Graduate Scholarships, Queen Elizabeth II Graduate Scholarships in Science and Technology, Canada Foundation for Innovation
165

La collaboration médecin-pharmacien en soins de première ligne pour la gestion des dyslipidémies : un essai clinique contrôlé et randomisé en grappe (étude TEAM)

Villeneuve, Julie 07 1900 (has links)
L’hypothèse de cette thèse est qu’une pratique collaborative médecins de famille-pharmaciens communautaires (PCMP) où le pharmacien fournit des soins pharmaceutiques avancés avec ajustement posologique d’une statine permettrait aux patients avec une dyslipidémie une réduction plus importante de leur LDL et augmenterait le nombre de patients atteignant leurs cibles lipidiques. Dans une étude clinique contrôlée et randomisée en grappe visant à évaluer une PCMP pour des patients ayant une dyslipidémie (l’étude TEAM), une journée de formation basée sur un protocole de traitement et des outils cliniques a été offerte aux pharmaciens PCMP pour les préparer à fournir des soins pharmaceutiques avancés. Les connaissances des pharmaciens sur les dyslipidémies étaient faibles avant la formation mais se sont améliorées après (moyenne de 45,8% à 88,2%; p < 0,0001). Après la formation, les pharmaciens avaient un haut niveau d’habiletés cliniques théoriques et pratiques. Bref, une journée de formation basée sur un protocole de traitement et des outils cliniques était nécessaire et adéquate pour préparer les pharmaciens à fournir des soins pharmaceutiques avancés à des patients ayant une dyslipidémie dans le contexte d’une étude clinique. Dans l’étude TEAM, 15 grappes de médecins et de pharmaciens (PCMP : 8; soins habituels (SH) : 7) ont suivi pendant un an, 225 patients (PCMP : 108; SH : 117) à risque modéré ou élevé de maladie coronarienne qui débutaient ou étaient déjà traités par une monothérapie avec une statine mais qui n’avaient pas atteint les cibles lipidiques. Au départ, par rapport aux patients SH, les patients PCMP avaient un niveau de LDL plus élevé (3,5 mmol/L vs 3,2 mmol/L) et recevaient moins de statine à puissance élevée (11,1 % vs 39,7 %). Après 12 mois, la différence moyenne du changement de LDL entre les groupes était égale à -0,2 mmol/L (IC95%: -0,3 à -0,1) et -0,04 (IC95%: -0,3 à 0,2), sans ajustement et avec ajustement, respectivement. Le risque relatif d’atteindre les cibles lipidiques était 1,10 (IC95%: 0,95 à 1,26) et 1,16 (1,01 à 1,32), sans ajustement et avec ajustement, respectivement. Les patients PCMP ont eu plus de visites avec un professionnel de la santé et d’analyses de laboratoire et étaient plus enclins à rapporter des changements de style de vie. La PCMP a amélioré l’adhésion aux lignes directrices en augmentant la proportion de patients aux cibles lipidiques. Les données intérimaires de l’étude TEAM (PCMP : 100 patients; SH : 67 patients) ont permis d’évaluer les coûts directs annuels du suivi du pharmacien du groupe PCMP (formation, visites, laboratoire), du médecin (visites, laboratoire) et du traitement hypolipémiant. Le suivi du pharmacien a coûté 404,07$/patient, incluant 320,67$ pour former les pharmaciens. Le coût global incrémental était 421,01$/patient. Une pratique collaborative pour des patients ayant une dyslipidémie engendre un coût raisonnable. / The hypothesis was that a family physician-community pharmacist collaborative care (PPCC) model where the pharmacist provides advanced pharmaceutical care including statin dosage adjustment would provide a greater LDL reduction to dyslipidemia patients and increase the number of patients reaching their target lipid levels. . In a cluster randomised controlled trial to evaluate a PPCC model for patients with dyslipidemia (TEAM study), a one-day workshop based on a treatment protocol and specific clinical tools was offered to prepare PPCC pharmacists to provide advanced pharmaceutical care to dyslipidemia patients. Pharmacists knowledge on dyslipidemia was low before the workshop but significantly improved thereafter (overall score from 45,8% to 88,2%; p < 0,0001). After the workshop, pharmacists showed a high level of theoretical and practical skills. Finally, a one-day workshop based on a treatment protocol and clinical tools was necessary and adequate to prepare pharmacists to provide advanced pharmaceutical care to patients with dyslipidemia in the context of a clinical trial. In the TEAM study, 15 clusters of physicians and pharmacists (PPCC: 8; usual care (UC) : 7) followed for 1 year, 225 patients (PPCC: 108; UC:117) at moderate or high risk of coronary heart disease who initiated or were already treated with a statin monotherapy but who did not achieved target lipid levels. At baseline, compared to UC patients, PPCC patients had a higher level of LDL (3.54 mmol/L vs 3.22 mmol/L) and were prescribed less high-potency statin (11,1% vs 39,7%). At 12 months, the crude and adjusted between group-differences in the mean change in LDL-C were equal to -0.2 mmol/L (95%CI: -0.3 to -0.1) and -0.04 (95%CI: -0.3 to 0.2), respectively. The crude and the adjusted relative risk of achieving lipid targets were equal to 1.10 (95%CI: 0.95 to 1.26) and 1.16 (1.01 to 1.32), respectively. PPCC patients had more health-professional visits and laboratory tests, were more likely to have their lipid-lowering treatment changed, and to report lifestyle changes. PPCC improved adherence to treatment-guideline recommendations with higher proportion of patients achieving their target lipid levels. From an interim analysis of the TEAM study (PPCC: 100 patients; UC: 67 patients) the annual direct costs for the pharmacist follow-up in the PPCC group (training, visits, laboratories), physician follow-up (visits, laboratories) and lipid-lowering treatment were evaluated. The cost for the pharmacist follow-up was $404.07/patient, including $320.67 to train pharmacists. The incremental overall cost was $421.01/patient. Finally, a PPCC for patients with dyslipidemia entails a reasonable cost.
166

Intestin et défauts métaboliques dans la résistance à l'insuline

Grenier, Émilie 12 1900 (has links)
En lien avec l’augmentation constante de l’obésité, de plus en plus de personnes sont atteintes de résistance à l’insuline ou de diabète de type 2. Ce projet doctoral s’est surtout intéressé à l’une des conséquences majeures des pathologies cardiométaboliques, soit la dyslipidémie diabétique. À cet égard, les gens présentant une résistance à l’insuline ou un diabète de type 2 sont plus à risque de développer des perturbations lipidiques caractérisées essentiellement par des taux élevés de triglycérides et de LDL-cholestérol ainsi que de concentrations restreintes en HDL-cholestérol dans la circulation. Les risques de maladies cardiovasculaires sont ainsi plus élevés chez ces patients. Classiquement, trois organes sont connus pour développer l’insulino-résistance : le muscle, le tissu adipeux et le foie. Néanmoins, certaines évidences scientifiques commencent également à pointer du doigt l’intestin, un organe critique dans la régulation du métabolisme des lipides postprandiaux, et qui pourrait, conséquemment, avoir un impact important dans l’apparition de la dyslipidémie diabétique. De façon très intéressante, des peptides produits par l’intestin, notamment le GLP-1 (glucagon-like peptide-1), ont déjà démontré leur potentiel thérapeutique quant à l’amélioration du statut diabétique et leur rôle dans le métabolisme intestinal lipoprotéinique. Une autre évidence est apportée par la chirurgie bariatrique qui a un effet positif, durable et radical sur la perte pondérale, le contrôle métabolique et la réduction des comorbidités du diabète de type 2, suite à la dérivation bilio-intestinale. Les objectifs centraux du présent programme scientifique consistent donc à déterminer le rôle de l’intestin dans (i) l’homéostasie lipidique/lipoprotéinique en réponse à des concentrations élevées de glucose (à l’instar du diabète) et à des peptides gastro-intestinaux tels que le PYY (peptide YY); (ii) la coordination du métabolisme en disposant de l’AMPK (AMP-activated protein kinase) comme senseur incontournable permettant l’ajustement précis des besoins et disponibilités énergétiques cellulaires; et (iii) l’ajustement de sa capacité d’absorption des graisses alimentaires en fonction du gain ou de la perte de sa sensibilité à l’insuline démontrée dans les spécimens intestinaux humains prélevés durant la chirurgie bariatrique. Dans le but de confirmer le rôle de l’intestin dans la dyslipidémie diabétique, nous avons tout d’abord utilisé le modèle cellulaire intestinal Caco-2/15. Ces cellules ont permis de démontrer qu’en présence de hautes concentrations de glucose en basolatéral, telle qu’en condition diabétique, l’intestin absorbe davantage de cholestérol provenant de la lumière intestinale par l’intermédiaire du transporteur NPC1L1 (Niemann Pick C1-like 1). L’utilisation de l’ezetimibe, un inhibiteur du NPC1L1, a permis de contrecarrer cette augmentation de l’expression de NPC1L1 tout comme l’élévation de l’absorption du cholestérol, prouvant ainsi que le NPC1L1 est bel et bien responsable de cet effet. D’autre part, des travaux antérieurs avaient identifié certains indices quant à un rôle potentiel du peptide intestinal PYY au niveau du métabolisme des lipides intestinaux. Toutefois, aucune étude n’avait encore traité cet aspect systématiquement. Pour établir définitivement l’aptitude du PYY à moduler le transport et le métabolisme lipidique dans l’intestin, nous avons utilisé les cellules Caco-2/15. Notre étude a permis de constater que le PYY incubé du côté apical est capable de réduire significativement l’absorption du cholestérol et le transporteur NPC1L1. Puisque le rôle de l'AMPK dans l'intestin demeure inexploré, il est important non seulement de définir sa structure moléculaire, sa régulation et sa fonction dans le métabolisme des lipides, mais aussi d'examiner l'impact de l’insulino-résistance et du diabète de type 2 (DT2) sur son statut et son mode d’action gastro-intestinal. En employant les cellules Caco-2/15, nous avons été capables de montrer (i) la présence de toutes les sous-unités AMPK (α1/α2/β1/β2/γ1/γ2/γ3) avec une différence marquée dans leur abondance et une prédominance de l’AMPKα1 et la prévalence de l’hétérotrimère α1/β2/γ1; (ii) l’activation de l’AMPK par la metformine et l’AICAR, résultant ainsi en une phosphorylation accrue de l’enzyme acétylCoA carboxylase (ACC) et sans influence sur l'HMG-CoA réductase; (iii) la modulation négative de l’AMPK par le composé C et des concentrations de glucose élevées avec des répercussions sur la phosphorylation de l’ACC. D’autre part, l’administration de metformine au Psammomys obesus, un modèle animal de diabète et de syndrome métabolique, a conduit à (i) une régulation positive de l’AMPK intestinale (phosphorylation de l’AMPKα-Thr172); (ii) la réduction de l'activité ACC; (iii) l’augmentation de l’expression génique et protéique de CPT1, supportant une stimulation de la β-oxydation; (iv) une tendance à la hausse de la sensibilité à l'insuline représentée par l’induction de la phosphorylation d'Akt et l’inactivation de la phosphorylation de p38; et (v) l’abaissement de la formation des chylomicrons ce qui conduit à la diminution de la dyslipidémie diabétique. Ces données suggèrent que l'AMPK remplit des fonctions clés dans les processus métaboliques de l'intestin grêle. La preuve flagrante de l’implication de l’intestin dans les événements cardiométaboliques a été obtenue par l’examen des spécimens intestinaux obtenus de sujets obèses, suite à une chirurgie bariatrique. L’exploration intestinale nous a permis de constater chez ceux avec un indice HOMA élevé (marqueur d’insulinorésistance) (i) des défauts de signalisation de l'insuline comme en témoigne la phosphorylation réduite d'Akt et la phosphorylation élevée de p38 MAPK; (ii) la présence du stress oxydatif et de marqueurs de l'inflammation; (iii) la stimulation de la lipogenèse et de la production des lipoprotéines riches en triglycérides avec l’implication des protéines clés FABP, MTP et apo B-48. En conclusion, l'intestin grêle peut être classé comme un tissu insulino-sensible et répondant à plusieurs stimuli nutritionnels et hormonaux. Son dérèglement peut être déclenché par le stress oxydatif et l'inflammation, ce qui conduit à l'amplification de la lipogenèse et la synthèse des lipoprotéines, contribuant ainsi à la dyslipidémie athérogène chez les patients atteints du syndrome métabolique et de diabète de type 2. / In relation with the constant increase in obesity, more and more people suffer from insulin resistance and type 2 diabetes (DT2). This doctoral research program especially emphasizes lipid disorders, one of the major consequences of cardiometabolic diseases. In this respect, people with insulin resistance or DT2 are at higher risk of developing lipid disturbances characterized mainly by high levels of triglycerides and LDL-cholesterol concentrations and HDL cholesterol in the blood circulation. The risks of cardiovascular disease are higher in these patients. Classically, three organs are known to develop insulin resistance: muscle, adipose tissue and liver. Nevertheless, important studies begin to point out the small intestine as a major organ in the regulation of postprandial lipids, which may have a significant impact on the development of diabetic dyslipidemia. In addition, the intestine produces peptides, including GLP-1 (glucagon-like peptide-1), that have already demonstrated their therapeutic potential with regard to diabetic status and intestinal lipoprotein metabolism. Further evidence is also is provided by the advent of bariatric surgery that has a positive effect on radical and sustainable weight loss, metabolic control and reduction of comorbidities of DT2, following biliopancreatic diversion. The central objectives of this scientific program are therefore to determine the role of the intestine in (i) lipid/ lipoprotein homeostasis in response to high concentrations of glucose (mimicking diabetes) and to gastrointestinal peptides such as PYY; (ii) the coordination of metabolism by involving AMPK (AMP-activated protein kinase) as an essential sensor for fine tuning of cellular energy needs; and (iii) adjusting absorption capacity of dietary fat in the gain or loss of insulin sensitivity demonstrated in intestinal specimens collected during bariatric surgery. In order to confirm the role of the intestine in diabetic dyslipidemia, we first used the intestinal Caco-2/15 cell model. The use of this epithelial cell line has shown a marked stimulation of cholesterol uptake via the transporter NPC1L1 (Niemann-Pick C1-like 1) in the presence of high glucose concentrations (as is the case in diabetic conditions) in basolateral compartment (compared to apical). The use of ezetimibe, an inhibitor of NPC1L1, helped to counteract this elevation of cholesterol absorption, thus proving that NPC1L1 is indeed behind this effect. If previous reports have identified some clues as to the potential role of intestinal PYY (peptide YY) in lipid metabolism disorders, no study has yet addressed this issue systematically. To definitively establish the ability of PYY to modulate lipid transport and metabolism in the intestine, we have used Caco-2/15 cells. Our recent investigation has shown that PYY (administered in the apical compartment) is able to significantly reduce cholesterol absorption via NPC1L1 transporter. Since the role of AMPK in the intestine remains unexplored, it is important to define not only its molecular structure, regulation and function in lipid metabolism, but also its impact on insulin resistance and T2D on its status and mode of action in the gastrointestinal tract. Using Caco-2/15 cells, we have been able to show (i) the presence of all AMPK subunits (α1/α2/β1/β2/γ1/γ2/γ3) with a marked difference in their abundance, but with a predominance of AMPKα1 and the prevalence of α1/β2/γ1 heterotrimer; (ii) the activation of AMPK by metformin and AICAR, resulting in increased phosphorylation of the downstream target acetylCoA carboxylases (ACC) without no influence on HMG-CoA reductase; (iii) the negative modulation of AMPK by compound C and glucose concentrations with high impact on ACC phosphorylation. On the other hand, administration of metformin to Psammomys obesus with insulin resistance and T2D led to (a) an upregulation of intestinal AMPK signaling pathway essentially typified by ascending AMPKα-Thr172 phosphorylation; (b) a reduction in ACC activity; (c) an elevation in the gene and protein expression of CPT1, supporting a stimulation of β-oxidation; (d) a trend of increase in insulin sensitivity portrayed by augmentation of Akt and GSK3β phosphorylation; (e) an inactivation of the stress-responsive p38-MAPK and /ERK1/2 exemplified by their phosphorylation lessening; and (f) a decrease in diabetic dyslipidemia following lowering of intracellular events that govern lipoprotein assembly. Therefore these data suggest that AMPK fulfills key functions in metabolic processes in the small intestine. The clear evidence for the involvement of the gut in cardiometabolic events has been obtained through the scrutiny of intestinal specimens obtained from obese subjects after bariatric surgery. Intestine of insulin-resistant subjects shows defects in insulin signaling as demonstrated by reduced Akt phosphorylation but increased p38 MAPK phosphorylation. These defects were accompanied with increased oxidative stress and inflammation markers in intestine of insulin-resistant subjects. Enhanced de novo lipogenesis rate and apo B-48 biogenesis along with increased triglyceride-rich lipoprotein production was also observed in the intestine of insulin-resistant subjects. Concomitantly, fatty acid binding proteins (FABP) and microsomal transfer protein (MTP) expression was increased in the intestine of insulin-resistant subjects. In conclusion, the small intestine may be classified as an insulin-sensitive tissue. Its deregulation, possibly triggered by oxidative stress and inflammation, may lead to amplification of lipogenesis and lipoprotein synthesis and may therefore represent a key mechanism for atherogenic dyslipidemia in patients with metabolic syndrome and T2D.
167

Mitochondrial dysfunction in survivors of acute lymphoblastic leukemia

Leahy, Jade 08 1900 (has links)
No description available.
168

Comparação entre 2 protocolos para indução do DM2 e avaliação do efeito do exercício físico moderado sobre a lipotoxicidade e os eicosanóides / Comparison between 2 protocols for T2D induction and evaluation of the effect of moderate physical exercise on lipotoxicity and eicosanoids

Lima, Kamila Lauany Lucas 26 October 2018 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-11-19T11:23:59Z No. of bitstreams: 2 Dissertação - Kamila Lauany Lucas Lima - 2018.pdf: 1815959 bytes, checksum: bc2167df3f3d8cab7e32728d28ff5a43 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-11-19T11:32:54Z (GMT) No. of bitstreams: 2 Dissertação - Kamila Lauany Lucas Lima - 2018.pdf: 1815959 bytes, checksum: bc2167df3f3d8cab7e32728d28ff5a43 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-11-19T11:32:54Z (GMT). No. of bitstreams: 2 Dissertação - Kamila Lauany Lucas Lima - 2018.pdf: 1815959 bytes, checksum: bc2167df3f3d8cab7e32728d28ff5a43 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-10-26 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The present study aimed to test whether: 1) the high fat diet can induce T2D without the administration of streptozotocin (STZ); 2) the high fat caloric intake causes metabolic, behavioral and morphological changes, similar to t2D and; 3) the practice of moderate physical exercise is effective to reverse the metabolic changes caused by T2D and of the high fat diet. To test these hypotheses, we used 57 Wistar 8 week old rats. They were splited into the five experimental groups: group D (N = 25) who received a single intraperitoneal dose of streptozotocin (STZ diluted in citrate buffer, pH 4.5-25mg / kg body weight of the animal) and were fed with high fat diet. To test the effect only of the high fat diet, the HL group (N = 8) was fed with high fat diet but did not receive the STZ injection. Animals with similar ages were used as control (CO, N = 24) and fed with a balanced diet. At the end of the third week, animals of CO and D and HL groups were subdivided into two other groups: sedentary (SE) and exercised (EF). EF groups were submitted to swimming for 6 weeks. The D-SE, D-EF and HL-SE groups presented significant changes in body weight gain, abdominal fat gain, caloric intake, food efficiency, lipid profile and fasting and capillary glucose levels, when compared to control groups. There was no significant difference in the concentrations of arachidonic acid products and the renal tissue did not present morphological alterations. Physical exercise increased high density lipoproteins (HDL), but did not change others evaluated parameters. We conclude that consumption of the high fat diet when associated with sedentary behavior may cause metabolic alterations similar to T2D and that physical exercise was efficient to improve the lipid profile. / Os objetivos do presente estudo foram investigar as seguintes hipóteses: 1) a dieta hiperlipídica pode induzir o Diabetes Mellitus tipo 2 (DM2) sem a administração de streptozotocina (STZ); a ingestão de dieta hiperlipídica e hipercalórica causam alterações metabólicas, comportamentais e morfológicas, similares ao DM2 e; 3) a prática de exercício físico moderado tem potencial sobre as alterações metabólicas causadas pelo DM2 e pela dietahiperlipídica. Para testarmos essas hipóteses foram utilizados 57 ratos Wistar com 8 semanas de idade, distribuídos nos seguintes grupos experimentais: grupo D (N=25) que receberam uma única injeção intraperitoneal de estreptozotocina (STZ diluído em tampão de citrato, pH 4,5 - 25mg/kg de peso corporal do animal) e foram alimentados com dieta hiperlipídica. Para testar o efeito somente da dieta hiperlipídica, o grupo HL (N=8), recebeu uma dieta hiperlipídica, mas não recebeu a injeção de STZ. Animais com idades similares foram utilizados como controle (CO, N=24) e alimentados com dieta balanceada. No final da terceira semana, animais dos grupos CO e D e HL foram subdivididos em dois grupos: sedentário (SE) e exercitado (EF). Os grupos EF foram submetidos a um protocolo de natação durante 6 semanas. Após o protocolo experimental, os grupos D-SE, D-EF e HL-SE apresentaram alterações significativas no ganho de massa, gordura abdominal, ingestão calórica, eficiência alimentar, perfil lipídico e glicemia em jejum e capilar quando comparados aos animais controles. Não houve diferença significativa nas concentrações dos produtos do ácido araquidônico e o tecido renal não apresentou alterações morfológicas. O exercício físico aumentou as lipoproteínas de alta densidade (HDL), mas não alterou os demais parâmetros avaliados. Concluímos que o consumo da dieta hiperlipídica quando associada ao comportamento sedentário pode causar alterações metabólicas similares ao DM2 e que o exercício físico foi eficiente para melhorar o perfil lipídico.
169

Estudo de variantes da leptina do receptor de leptina: impacto sobre as características relacionadas com a obesidade / Study of the leptin and the leptin receptor gene variants: impact on characteristics related with obesity

Raquel de Oliveira 17 June 2008 (has links)
Neste estudo, foi avaliada a relação entre polimorfismos dos genes da leptina (LEP) e receptores da leptina (LEPR) e parâmetros antropométricos, leptinemia glicemia e lipídeos séricos, em indivíduos da população brasileira. Foram incluídos 238 indivíduos com idade entre 30 e 80 anos. Foram medidos o índice de massa corporal (IMC), a cintura abdominal (CA) e a razão cintura quadril (RCQ). Amostras de sangue periférico foram obtidas para análise do perfil bioquímico e extração de DNA. Os polimorfismos de nuleotideo único (SNPs) LEP G-2548A e LEPR Lys109Arg, Gln223Arg e Lys656Asn foram detectados por PCR-RFLP. Os SNPs LEPR Lys109Arg e Gln223Arg foram associados com obesidade e com IMC e CA aumentados (p<0.05). Estes polimorfismos também foram associados com leptina e glicose elevada (p<0,05). O perfil lipídico sérico foi influenciado pelo polimorfismo LEPR Lys109Arg (p<0.05). A relação entre os SNPs LEPR Lys109Arg e Gln223Arg e o perfil lipídico foi modificada pelo gênero. Os haplótipos LEP G-2548/ LEPR Lys109Arg foram relacionados com diferenças no IMC de obesos. Os haplotipos LEPR Lys109Arg/Gln223Arg foram associados com diferenças na CA e glicemia e lipídeos séricos. Em conclusão, os polimorfismos LEPR Lys109Arg e Gln223Arg estão associados com obesidade e alterações de leptina, glicose e lipídeos circulantes de forma dependente do gênero. / We have assessed the relationship between polymorphisms of the leptin (LEP) and the leptin receptor (LEPR) genes and anthropometric parameters, plasma leptin and glucose and serum lipids in individuals of the Brazilian population. We included 238 individuais with 30 to 80 years. Body mass index (BMI), abdominal circumference (AC) and waist-to-hip ratio (WHR) were measured. Peripheral blood samples were collected for analysis of the biochemical profile and DNA extraction. The single nucleotide polymorphisms (SNP) LEP G-2548A and LEPR Lys109Arg, Gln223Arg and Lys656Asn were detected by PCR-RFLP. The SNPs LEPR Lys109Arg and Gln223Arg were associated with obesity and with increased BMI and AC (p <0.05). These polymorphisms were also associated with increase leptin and glucose (p<0,05). The serum lipid profile was influenced by the LEPR Lys 1 09Arg (p<0.05). The relationship between the SNPs LEPR Lys 1 09Arg and Gln223Arg and the lipid profile was modified by gender. The haplotypes LEP G-2548A1 LEPR Lys109Arg were related with differences on BMI in obese group. The haplotypes LEPR Lys109Arg/Gln223Arg were associated with differences on AC, glucose and serum lipids. In conclusion, the LEPR Lys109Arg and Gln223Arg polymorphisms are associated with obesity and alterations in blood leptin, glucose and lipids in a gender-dependent manner.
170

Signification des plis palmaires orangés dans l’évaluation des dyslipidémies

Roy, Nathalie 12 1900 (has links)
Après un bref rappel des facteurs de risque cardiovasculaires et une revue du métabolisme des lipides, de la classification des dyslipidémies et de la pathophysiologie des xanthomes, sera abordée la dysbêtalipoprotéinémie (anciennement la dyslipidémie de type III). Cette dyslipidémie caractérisée par l’accumulation de particules de remnants, généralement secondaire à une apolipoprotéine E anormale, est hautement athérogène, tant au niveau vasculaire périphérique que coronarien. Jusqu’à présent, les plis palmaires orangés, définis comme étant une coloration jaune à orangée (parfois brunâtre) des plis palmaires ainsi que digitaux, ont été considérés pathognomoniques de cette dyslipidémie. Par l’étude d’une population caucasienne adulte du Saguenay –Lac Saint-Jean, nous avons pu démontrer une prévalence de 18,8% des plis palmaires orangés chez les patients atteints d’une dysbêtalipoprotéinémie. Également, cette étude a permis de mettre en lumière l’absence des critères de dysbêtalipoprotéinémie chez 10,7% des sujets présentant ce type de xanthome. Les données suggèrent que l’expression de plis palmaires orangés est associée à la présence d’une accumulation soutenue ou récurrente de remnants. L’accumulation de ces remnants est possible dans un large spectre de maladies lipidiques où il y a interférence dans l’hydrolyse ou la clairance des remnants, dont la dyslipidémie post-prandiale, la chylomicronémie, le déficit partiel en lipoprotéine lipase (LPL) et dans l’hypercholestérolémie familiale (HF) sévère, principalement chez les individus homozygotes. La recherche en clinique des plis palmaires orangés pourrait apporter des éléments complémentaires dans l’évaluation du risque cardiovasculaire en tant que marqueur d’une accumulation de remnants qui, pour leur part, ont été démontrés conférer un risque cardiovasculaire augmenté, tant en prévention primaire que secondaire. / After a brief review of cardiovascular risk factors and lipid metabolism, classification of dyslipidemias, the pathophysiology of xanthomas as well as dysbetalipoproteinemia will be discussed. This dyslipidemia which is characterized by the accumulation of remnants particules, generally secondary to an abnormal apolipoprotein E, is highly atherogenic, both at the peripheral vascular and coronary levels. The striated palmar xanthomas, defined as a yellow to orange (sometimes brownish) coloration of the palmar and digital folds, are considered pathognomonic of this formerly called type III dyslipidemia. By studying an adult Caucasian population from the Saguenay–Lac Saint-Jean region, we were able to demonstrate a prevalence of 18.8% of orange palmar folds in patients with dysbetalipoproteinemia. Also, this study allowed to shed light on the absence of criteria for dysbetalipoproteinemia in 10.7% of subjects with this type of xanthoma. These data suggest that the expression of striated palmar xanthomas is associated with the presence of a sustained or recurrent accumulation of remnants. The accumulation of these remnants is possible in a broad spectrum of lipid disorders where there is interference in the hydrolysis or clearance of the remnants, including postprandial dyslipidemia, chylomicronemia, partial lipoprotein lipase deficiency and familial hypercholesterolemia mainly in homozygotes. Clinical research of striated palmar xanthomas could provide additional information in the evaluation of cardiovascular risk as a marker of an accumulation of remnants which, for their part, have been shown to confer an increased cardiovascular risk, both in primary prevention and secondary.

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