Para avaliar o efeito de uma refeição-teste rica em lipídeos, assim mimetizando o estado pós-prandial durante o dia, nos parâmetros metabólicos e na reatividade vascular, foram estudados quatro grupos de pacientes do sexo masculino, assim divididos: com diabetes mellitus Tipo 2 e sem doença arterial coronariana (DM, n = 10), com doença arterial coronariana e com diabetes mellitus Tipo 2 (DM + DAC, n = 11), com doença arterial coronariana e sem diabetes mellitus (DAC, n = 11) e Controle (n = 7). Todos os pacientes, após receberem uma dieta rica em gordura (60g) e pobre em hidratos de carbono (14g), foram avaliados em termos de perfil lipídico antes (0h) e 2h, 4h, 6h e 8h após a ingestão e realizada a avaliação da reatividade vascular nos tempos 0h, 4h e 8h. A reatividade vascular foi estudada por ultra-som de alta resolução, medindo-se a resposta vasodilatadora da artéria braquial durante hiperemia reativa (vasodilatação endotélio-dependente) e após administração de nitroglicerina (endotélio-independente). HbA1c não foi diferente entre os grupos do estudo, exceto, como seria de se esperar, nos Controles, que foi normal (média ± DP) (DAC: 6,3 ± 0,6% vs DM + DAC: 7,6 ± 1,6% vs DM: 6,8 ± 1,7% vs Controle: 5,43 ± 0,45%). Por outro lado, a glicemia e insulina de jejum foram significativamente menores dos DAC e grupo Controle, sendo similar nos dois grupos. Dos outros parâmetros metabólicos, apenas o ácido úrico foi significativamente maior no grupo DAC (p = 0,025) em comparação aos outros. Vasodilatação da artéria braquial pós-isquemia antes do teste de sobrecarga foi semelhante entre os grupos (DAC: 7,44 ± 4,30% vs 7,01 ± 4,53% no DM vs 10,34 ± 5,10% no DM+DAC vs 9,91 ± 2,97% no grupo Controle. A vasodilatação após administração de nitrato (realizada no dia anterior ao teste de sobrecarga lipídica) também se manteve dentro da normalidade nos quatro grupos, sem diferença entre eles (DAC: 19,85 ± 8,66% vs 15,68 ± 11,43% no DM vs 21,24 ± 11,82% no DM+DAC e 20,05 ± 3,73% no grupo Controle). HOMAIR (Homeostasis Model for Assessment of insulin resistance) aumentou progressivamente nos grupos DAC, DM e DM+DAC, respectivamente, sendo significativamente menor no grupo Controle. Após sobrecarga, os níveis de triglicerídeos aumentaram significativamente nos quatro grupos, com pico nos tempos 4h e 6h (p < 0,001 nos quatro grupos para 2h, 4h, 6h e 8h vs 0h). O colesterol total apresentou aumento, com p < 0,001 para 4h e 6h e p = 0,0019 para 8h, em comparação com 0h, nos quatro grupos. O LDL-colesterol (p = 0,001) e o HDL-colesterol (p < 0,001) apresentaram decréscimo em todos os tempos após o teste em relação ao basal. Não houve diferença significativa entre os quatro grupos no perfil lipídico após sobrecarga de gordura. A glicemia foi significativamente mais baixa nos grupos DAC e Controle do que nos grupos DM e DM+DAC. Nos grupos DAC e Controle, a glicemia manteve-se inalterada durante o teste. Os grupos DM e DM+DAC apresentaram um decréscimo significativo nos níveis glicêmicos nos tempos 4h, 6h e 8h. (p<0,001 para todos os grupos em relação ao tempo 0h). O comportamento da insulinemia foi semelhante entre os grupos e todos mostraram elevação nos tempos 2h (p<0,001) vs 0h, havendo progressiva queda no decorrer dos tempos, chegando aos níveis basais na oitava hora. A reatividade vascular foi semelhante entre os quatro grupos e não houve diferença nas medidas após sobrecarga. No grupo DM ocorreu uma redução limítrofe na reatividade vascular após a ingestão da sobrecarga lipídica (p = 0,0556). A vasodilatação pós-nitroglicerina também foi semelhante entre os grupos, assim como os resultados obtidos antes e após sobrecarga quando comparados entre si. Este estudo permitiu concluir que a hiperlipemia pós-sobrecarga lipídica nos grupos DAC, DM, DM+DAC e Controle resultou em hiperinsulinemia sem elevação glicêmica, mas sem efeito significativo da reatividade vascular, tanto quando avaliada pela hiperemia reativa (endotélio-dependente), quanto quando estimulada com vasodilatador (endotélio-independente) / To assess the effect of a high-fat meal to simulate to post-prandial state during the day, on the metabolic parameters and endothelial function, four groups of male patients with Coronary Heart Disease and without Diabetes Mellitus (DAC, n= 11); with known Type 2 Diabetes Mellitus and no Coronary Heart Disease (DM, n= 10); and with both Type 2 Diabetes and Coronary Heart Disease (DM+DAC, n = 11) as well as seven healthy controls (Control n = 7) were evaluated before and after receiving a high fat (60g) low carbohydrate (14g) meal test. Lipid profile (basal and 2, 4, 6 and 8 hours after the meal-test) and Vascular reactivity (2, 4 and 8h) were measured. Vascular reactivity was evaluated using high-resolution ultrasound and assessing brachial artery\'s vasodilatory responses during reactive hyperemia (endothelium-dependent vasodilatation), and after nitroglycerin administration, an endotheliumindependent vasodilator. Mean ± SD HbA1c was not significantly by different between groups (DAC: 6.3 ± 0.6% vs DM + DAC: 7.6 ± 1.6% vs DM: 6.8 ± 1,7%) except, as expected in the Control (5.43 ± 0.45%). Furthermore, fasting plasma glucose and insulin were significantly lower in the DAC and Control being however similar in both groups. DAC group had significant by higher uric acid levels than the other three groups (p = 0.025). Post-ischemia brachial artery vasodilation was similar among groups before lipid overload (DAC: 7.44 ± 4.30% vs 7.01 ± 4.53% no DM vs 10.34 ± 5.10% no DM+DAC vs 9.91 ± 2.97% in the Control). Basal change in the brachial artery diameter after sublingual nitrate, performed the day before the fat test, was also within the accepted normal range in all four groups, with no difference in between them (DAC: 19.85 ± 8.66% vs 15.68 ± 11.43 in DM vs 21.24 ± 11.82% in DM+DAC and 20.05 ± 3.73% in the Control). Homeostasis Model for Assessment of insulin sensitivity (HOMAIR) increased significantly and progressively from DAC to DM and to DM+DAC groups, however being significantly lower in the Control. After the fat overload test all four groups had a major increase in triglyceride levels peaking at 4h and 6h after the ingestion (p<0.001) for four groups for 2h, 4h, 6h and 8h vs 0h). Total cholesterol had a increase at all times of sampling (p < 0.001), while LDL-cholesterol (p < 0.001) and HDL-cholesterol (p = 0.001) decreased after the test-meal. Overall, there were no statistical differences among the four groups regarding post load-lipid profile. Glycemia was statistically lower in DAC and Control versus DM and DM+DAC groups. In DAC and Control glicemia was unchanged during testing, DM and DM+DAC groups had a considerable glycemic decrease at times 4h, 6h and 8h after fat-load (p<0.001, for both groups vs 0h). Insulin behaviors was similar among all four groups all of which showed higher levels at 2h (p<0.001 vs 0h, there being a progressive decrease during the test becoming within the basal range at the 8th hour. Vascular reactivity was similar within the four groups and there was no difference through the different measures after fat-loading. In the diabetic group without coronary hearth disease there was a borderline reduction in vascular reactivity after the fat load (p = 0.0556). Vasodilation after nitroglycerin was comparable among the groups again with no differences in the response before and after fat-loading. In conclusion this study showed than the post-load hyperlipemia in DAC,DM, DM+DAC and Control groups resulted in hyperinsulinemia without hyperglycemia and had no significant effects on vascular reactivity both endothelial dependent (hyperemia reactivity) and independent

Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-06-14T17:35:19Z No. of bitstreams: 1 DanyloMelo.pdf: 745489 bytes, checksum: c5ad51adb0decdb7d8050bcf5074660b (MD5) / Made available in DSpace on 2017-06-14T17:35:19Z (GMT). No. of bitstreams: 1 DanyloMelo.pdf: 745489 bytes, checksum: c5ad51adb0decdb7d8050bcf5074660b (MD5) Previous issue date: 2016-09-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ) / Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico e Tecnológico do Maranhão (FAPEMA) / Synthetic glucocorticoids (GCs) induce several adverse effects when administered in high doses and/or prolonged, as peripheral insulin resistance, glucose intolerance, and alterations in lipid metabolism, especially hypertriglyceridemia. There are few studies on the metabolic impact caused by long-term treatments with different synthetic GCs, especially with prednisone, GC of intermediate action and first choice in its pharmacologic class. Therefore, we seek to verify the metabolic alterations caused by sub chronic treatment with prednisone in rats and compare them with existing and in acute model of insulin resistance induced by dexamethasone effects. For this, Wistar rats with of 90 days were treated with dexamethasone (D5) (1 mg/kg, i.p.) for 5 consecutive days and, its controls (C5) with saline, and Wistar rats of 60 days old were treated with prednisone (80 mg/kg, orally) for 15 days (P15) and 30 days (P30) consecutive and their respective controls (C15 and C30), received vehicle solution. The D5 results a decreased body weight (12.3%) and lower weight of retroperitoneal fat (38%), increased serum fasting glucose (12%) and fed (30%), insulin (80%) and triglycerides (339%) (p <0.05). Total fat and triglycerides liver were 29% and 52% higher in rats D5, compared to the C5 rats (p <0.05). The P15 rats had increased weight 61% less, reduction of retroperitoneal fat (29%) and increased plasma triglyceride concentrations (60%) compared to the C15 rats (p <0.05). As long as P30 rats had increased weight 44% less, reduction of retroperitoneal fat (25%) and increased serum triglycerides (78%) and liver total fat (26%) compared to the C30 rats (p <0,05). In vivo tests revealed the presence of impaired glucose tolerance (oGTT) in rats D5 and P30, and reduced insulin sensitivity (ipITT, HOMA, TYG) in D5 animals (p <0.05). Ex vivo test showed greater sensitivity in the pancreatic islets front glucose only in D5 rats. In conclusion, the sub chronic administration of prednisone promoted finer metabolic changes in glucose homeostasis, compared to acute administration of dexamethasone, suggesting the preferential use of prednisone when it is intended to minimize the adverse metabolic effects associated with the use of GCs. / Os glicocorticoides (GCs) sintéticos podem induzir diversos efeitos adversos, quando administrados em doses elevadas e/ou por tempo prolongado, como resistência insulínica periférica, intolerância à glicose, e alterações no metabolismo lipídico, especialmente hipertrigliceridemia. Porém existem poucos estudos sobre o impacto metabólico promovido por tratamentos prolongados com diferentes GCs sintéticos, especialmente com a prednisona, GC de ação intermediária e de primeira escolha em sua classe farmacológica. Diante disso, buscou-se verificar as alterações metabólicas ocasionadas pelo tratamento subcrônico com prednisona em ratos e compará-las aos efeitos presentes e conhecidos em modelo agudo de indução de resistência insulínica pela dexametasona. Para tal, ratos Wistar com noventa dias de vida foram tratados com dexametasona (D5) (1 mg/Kg, i.p.) durante 5 dias consecutivos e, os seus controles (C5) com salina, e ratos Wistar com 60 dias de vida foram tratados com prednisona (80 mg/Kg, v.o.) durante 15 dias (P15) e 30 dias (P30) consecutivos e, os seus respectivos controles (C15 e C30), receberam veículo. Os ratos D5 apresentaram redução do peso corpóreo (12,3%) e menor peso da gordura retroperitoneal (38%), aumento das concentrações séricas de glicose em jejum (12%) e alimentado (30%), insulina (80%) e triglicerídeos (339%) (p<0,05). O conteúdo de gordura total hepático, bem como triglicerídeos foram 29% e 52% maiores nos ratos D5, em relação aos ratos C5 (p<0,05). Os ratos P15 apresentaram um ganho de peso 61% menor, redução da gordura retroperitoneal (29%) e aumento nas concentrações plasmáticas de triglicerídeos (60%), em relação aos ratos C15 (p<0,05). Enquanto os ratos P30 apresentaram um ganho de peso 44% menor, redução da gordura retroperitoneal (25%) e aumento nas concentrações séricas de triglicerídeos (78%) e gordura total hepática (26%), em relação aos ratos C30 (p<0,05). Os testes in vivo revelaram a presença de intolerância à glicose (GTT) nos ratos D5 e P30 e redução da sensibilidade à insulina (ITT, HOMA, TyG) nos animais D5 (p<0,05). O teste ex vivo revelou maior sensibilidade nas ilhotas pancreáticas frente à glicose somente nos ratos D5. Em conclusão, a administração subcrônica de prednisona promoveu alterações metabólicas mais sutis na homeostasia da glicose, quando comparada à administração aguda de dexametasona, sugerindo assim, o uso preferencial da prednisona quando se pretende minimização dos efeitos adversos metabólicos associados ao uso de GCs.

Objetivo Avaliar, em indivíduos com diabetes (DM), a resposta de glicose e triglicerídeos duas horas após a ingestão de uma carga alimentar (CA) e sua associação com características clínicas e a presença de doenças crônicas. Metodologia Foram incluídos 915 indivíduos com DM, participantes da linha de base do estudo ELSA-Brasil. Coleta de sangue foi realizada em jejum e duas horas após o consumo da CA, contendo 455 kcal; 14 g de gordura saturada e 47 g de carboidratos. Regressão linear foi utilizada para investigar preditores dos níveis de excursão (diferença entre níveis pós-carga e de jejum) de glicemia e trigliceridemia (variáveis dependentes). Regressão logística foi realizada para descrever a associação da excursão de glicemia e trigliceridemia (variáveis independentes) e a presença de complicações do DM (doença coronariana, infarto, angina, acidente vascular cerebral, ou insuficiência cardíaca). Resultados A mediana da glicemia de jejum foi de 150 (123–198) mg/dL e da excursão de glicose foi 45 (16–79) mg/dL, enquanto que a trigliceridemia de jejum foi de 140 (103–199) mg/dL e a excursão de triglicerídeos foi de 26 (11–45) mg/dL. Maiores excursões de glicemia foram associadas com duração do DM (incremento de 5,7 mg/dL, IC95% 3,7–7,6, a cada 5 anos de doença), uso de insulina (58,5 mg/dL, IC95% 45,43–71,55), outro medicamento para DM (13,6 mg/dL, IC95% 2,5–24,8), idade (4,1 mg/dL, IC95% 0,43–7,69, a cada 10 anos), nível de glicose basal (5,2 mg/dL, IC95% 1,0–4,1, a cada 25 mg/dL); o índice de massa corporal associou-se a menor excursão (-6,8 mg/dL, IC95% -9,7 a -3,85, a cada 5 kg/m²). Maior excursão de trigliceridemia esteve associada com glicemia em jejum (2,5 mg/dL, IC95% 1,64–3,38, a cada 25 mg/dL), e menor excursão associada com triglicerídeos de jejum (-2,97 mg/dL, IC95% -3,24 – -2,69, a cada 25 mg/dL). Conclusão A resposta pós-prandial esteve associada ao tempo de doença, à necessidade de insulina ou outro medicamento para DM, ao índice de massa corporal, além da idade e níveis basais de glicose e triglicerídeos. As excursões de glicose e triglicerídeos estiveram associadas a presença de comorbidades potencialmente tidas como complicações do DM. / Objective We aimed to assess, in individuals with diabetes (DM), the excursions of glucose and triglyceride levels two hours after consumption of a food load (FL) and their association with clinical characteristics and the presence of chronic diseases. Design and Methods We included 915 subjects with DM, participants of in the ELSA-Brazil cohort. Blood sampling was performed at fasting and two hours after consumption of a 455 kcal, 14 g saturated fat and 47 g carbohydrate FL. Linear regression was used to investigate predictors of levels of excursion (difference between post-load and fasting levels) of glucose and triglycerides (dependent variables). Logistic regression was performed to describe the association of glucose excursion and triglycerides excursion (independent variables) and the presence of DM complications (coronary heart disease, myocardial infarction, angina pectoris, stroke, or heart failure). Results The median fasting glucose was 150 (123-198) mg/dL and glucose excursion was 45 (16-79) mg/dL, whereas fasting triglycerides was 140 (103-199) mg/dL and triglycerides excursion was 26 (11-45) mg/dL. Increase of glucose excursion were associated with DM duration (increase of 5.7 mg/dL, 95% CI 3.7 to 7.6, each 5 years of disease), insulin use (58.5 mg/dL, 95% CI 45.43 to 71.55), use of another drug for DM (13.6 mg/dL , 95% CI 2.5 to 24.8), age (4.1 mg/dL, 95% CI 0.43 to 7.69, each 10 years), fasting glucose (5.2 mg/dL, 95% CI 1.0 to 4.1, each 25 mg/dL) and body mass index (-6.8 mg/dL, 95% CI -9.7 to -3.85, each 5 kg/m²). The triglycerides excursion was associated with fasting glucose (2.5 mg/dL, 95% CI 1.64 to 3.38, each 25 mg/dL) and fasting triglycerides (-2.97 mg/dL, 95% CI -3.24 to -2.69, each 25 mg/dL). In logistic regression models adjusting for gender, age, fasting glucose, duration of diabetes, use of insulin and/or other drug for DM, the excursion of glucose was marginally associated with the presence of any complication of diabetes and coronary heart disease. Conclusion Greater glycemic postprandial response was positively associated with indicators of less pancreatic reserve and negatively associated with obesity, while and the size of the response in triglycerides presented only minimal associations. Associations of excursion size with diabetes complications were present.

Individuals with high levels of plasma triglycerides are at high risk to develop cardiovascular disease (CVD), currently one of the major causes of death worldwide. Recent epidemiological studies show that loss-of-function mutations in the APOC3 gene lower plasma triglyceride levels and reduce the incidence of coronary artery disease. The APOC3 gene encodes for apolipoprotein (APO) C3, known as an inhibitor of lipoprotein lipase (LPL) activity. Similarly, a common gain-of-function mutation in the LPL gene is associated with reduced risk for CVD. LPL is central for the metabolism of lipids in blood. The enzyme acts at the endothelial surface of the capillary bed where it hydrolyzes triglycerides in circulating triglyceride-rich lipoproteins (TRLs) and thereby allows uptake of fatty acids in adjacent tissues. LPL activity has to be rapidly modulated to adapt to the metabolic demands of different tissues. The current view is that LPL is constitutively expressed and that the rapid modulation of the enzymatic activity occurs by some different controller proteins. Angiopoietin-like protein 4 (ANGPTL4) is one of the main candidates for control of LPL activity. ANGPTL4 causes irreversible inactivation through dissociation of the active LPL dimer to inactive monomers. Other proteins that have effects on LPL activity are the APOCs which are surface components of the substrate TRLs. APOC2 is a well-known LPL co-factor, whereas APOC1 and APOC3 independently inhibit LPL activity. Given the important role of LPL for triglyceride homeostasis in blood, the aim of this thesis was to find small molecules that could increase LPL activity and serve as lead compounds in future drug discovery efforts. Another aim was to investigate the molecular mechanisms for how APOC1 and APOC3 inhibit LPL activity. Using a small molecule screening library we have identified small molecules that can protect LPL from inactivation by ANGPTL4 during incubations in vitro. Following a structure-activity relationship study we have synthesized lead compounds that more efficiently protect LPL from inactivation by ANGPTL4 in vitro and also have dramatic triglyceride-lowering properties in vivo. In a separate study we show that low concentrations of fatty acids possess the ability to prevent inactivation of LPL by ANGPTL4 under in vitro conditions. With regard to APOC1 and APOC3 we demonstrate that when bound to TRLs, these apolipoproteins prevent binding of LPL to the lipid/water interface. This results in decreased lipolysis and in an increased susceptibility of LPL to inactivation by ANGPTL4. We demonstrate that hydrophobic amino acid residues that are centrally located in the APOC3 molecule are critical for attachment of this protein to lipid emulsion particles and consequently for inhibition of LPL activity. In summary, this work has identified a lead compound that protects LPL from inactivation by ANGPTL4 in vitro and lowers triglycerides in vivo. In addition, we propose a molecular mechanism for inhibition of LPL activity by APOC1 and APOC3.

Objetivo Avaliar, em indivíduos com diabetes (DM), a resposta de glicose e triglicerídeos duas horas após a ingestão de uma carga alimentar (CA) e sua associação com características clínicas e a presença de doenças crônicas. Metodologia Foram incluídos 915 indivíduos com DM, participantes da linha de base do estudo ELSA-Brasil. Coleta de sangue foi realizada em jejum e duas horas após o consumo da CA, contendo 455 kcal; 14 g de gordura saturada e 47 g de carboidratos. Regressão linear foi utilizada para investigar preditores dos níveis de excursão (diferença entre níveis pós-carga e de jejum) de glicemia e trigliceridemia (variáveis dependentes). Regressão logística foi realizada para descrever a associação da excursão de glicemia e trigliceridemia (variáveis independentes) e a presença de complicações do DM (doença coronariana, infarto, angina, acidente vascular cerebral, ou insuficiência cardíaca). Resultados A mediana da glicemia de jejum foi de 150 (123–198) mg/dL e da excursão de glicose foi 45 (16–79) mg/dL, enquanto que a trigliceridemia de jejum foi de 140 (103–199) mg/dL e a excursão de triglicerídeos foi de 26 (11–45) mg/dL. Maiores excursões de glicemia foram associadas com duração do DM (incremento de 5,7 mg/dL, IC95% 3,7–7,6, a cada 5 anos de doença), uso de insulina (58,5 mg/dL, IC95% 45,43–71,55), outro medicamento para DM (13,6 mg/dL, IC95% 2,5–24,8), idade (4,1 mg/dL, IC95% 0,43–7,69, a cada 10 anos), nível de glicose basal (5,2 mg/dL, IC95% 1,0–4,1, a cada 25 mg/dL); o índice de massa corporal associou-se a menor excursão (-6,8 mg/dL, IC95% -9,7 a -3,85, a cada 5 kg/m²). Maior excursão de trigliceridemia esteve associada com glicemia em jejum (2,5 mg/dL, IC95% 1,64–3,38, a cada 25 mg/dL), e menor excursão associada com triglicerídeos de jejum (-2,97 mg/dL, IC95% -3,24 – -2,69, a cada 25 mg/dL). Conclusão A resposta pós-prandial esteve associada ao tempo de doença, à necessidade de insulina ou outro medicamento para DM, ao índice de massa corporal, além da idade e níveis basais de glicose e triglicerídeos. As excursões de glicose e triglicerídeos estiveram associadas a presença de comorbidades potencialmente tidas como complicações do DM. / Objective We aimed to assess, in individuals with diabetes (DM), the excursions of glucose and triglyceride levels two hours after consumption of a food load (FL) and their association with clinical characteristics and the presence of chronic diseases. Design and Methods We included 915 subjects with DM, participants of in the ELSA-Brazil cohort. Blood sampling was performed at fasting and two hours after consumption of a 455 kcal, 14 g saturated fat and 47 g carbohydrate FL. Linear regression was used to investigate predictors of levels of excursion (difference between post-load and fasting levels) of glucose and triglycerides (dependent variables). Logistic regression was performed to describe the association of glucose excursion and triglycerides excursion (independent variables) and the presence of DM complications (coronary heart disease, myocardial infarction, angina pectoris, stroke, or heart failure). Results The median fasting glucose was 150 (123-198) mg/dL and glucose excursion was 45 (16-79) mg/dL, whereas fasting triglycerides was 140 (103-199) mg/dL and triglycerides excursion was 26 (11-45) mg/dL. Increase of glucose excursion were associated with DM duration (increase of 5.7 mg/dL, 95% CI 3.7 to 7.6, each 5 years of disease), insulin use (58.5 mg/dL, 95% CI 45.43 to 71.55), use of another drug for DM (13.6 mg/dL , 95% CI 2.5 to 24.8), age (4.1 mg/dL, 95% CI 0.43 to 7.69, each 10 years), fasting glucose (5.2 mg/dL, 95% CI 1.0 to 4.1, each 25 mg/dL) and body mass index (-6.8 mg/dL, 95% CI -9.7 to -3.85, each 5 kg/m²). The triglycerides excursion was associated with fasting glucose (2.5 mg/dL, 95% CI 1.64 to 3.38, each 25 mg/dL) and fasting triglycerides (-2.97 mg/dL, 95% CI -3.24 to -2.69, each 25 mg/dL). In logistic regression models adjusting for gender, age, fasting glucose, duration of diabetes, use of insulin and/or other drug for DM, the excursion of glucose was marginally associated with the presence of any complication of diabetes and coronary heart disease. Conclusion Greater glycemic postprandial response was positively associated with indicators of less pancreatic reserve and negatively associated with obesity, while and the size of the response in triglycerides presented only minimal associations. Associations of excursion size with diabetes complications were present.

Para avaliar o efeito de uma refeição-teste rica em lipídeos, assim mimetizando o estado pós-prandial durante o dia, nos parâmetros metabólicos e na reatividade vascular, foram estudados quatro grupos de pacientes do sexo masculino, assim divididos: com diabetes mellitus Tipo 2 e sem doença arterial coronariana (DM, n = 10), com doença arterial coronariana e com diabetes mellitus Tipo 2 (DM + DAC, n = 11), com doença arterial coronariana e sem diabetes mellitus (DAC, n = 11) e Controle (n = 7). Todos os pacientes, após receberem uma dieta rica em gordura (60g) e pobre em hidratos de carbono (14g), foram avaliados em termos de perfil lipídico antes (0h) e 2h, 4h, 6h e 8h após a ingestão e realizada a avaliação da reatividade vascular nos tempos 0h, 4h e 8h. A reatividade vascular foi estudada por ultra-som de alta resolução, medindo-se a resposta vasodilatadora da artéria braquial durante hiperemia reativa (vasodilatação endotélio-dependente) e após administração de nitroglicerina (endotélio-independente). HbA1c não foi diferente entre os grupos do estudo, exceto, como seria de se esperar, nos Controles, que foi normal (média ± DP) (DAC: 6,3 ± 0,6% vs DM + DAC: 7,6 ± 1,6% vs DM: 6,8 ± 1,7% vs Controle: 5,43 ± 0,45%). Por outro lado, a glicemia e insulina de jejum foram significativamente menores dos DAC e grupo Controle, sendo similar nos dois grupos. Dos outros parâmetros metabólicos, apenas o ácido úrico foi significativamente maior no grupo DAC (p = 0,025) em comparação aos outros. Vasodilatação da artéria braquial pós-isquemia antes do teste de sobrecarga foi semelhante entre os grupos (DAC: 7,44 ± 4,30% vs 7,01 ± 4,53% no DM vs 10,34 ± 5,10% no DM+DAC vs 9,91 ± 2,97% no grupo Controle. A vasodilatação após administração de nitrato (realizada no dia anterior ao teste de sobrecarga lipídica) também se manteve dentro da normalidade nos quatro grupos, sem diferença entre eles (DAC: 19,85 ± 8,66% vs 15,68 ± 11,43% no DM vs 21,24 ± 11,82% no DM+DAC e 20,05 ± 3,73% no grupo Controle). HOMAIR (Homeostasis Model for Assessment of insulin resistance) aumentou progressivamente nos grupos DAC, DM e DM+DAC, respectivamente, sendo significativamente menor no grupo Controle. Após sobrecarga, os níveis de triglicerídeos aumentaram significativamente nos quatro grupos, com pico nos tempos 4h e 6h (p < 0,001 nos quatro grupos para 2h, 4h, 6h e 8h vs 0h). O colesterol total apresentou aumento, com p < 0,001 para 4h e 6h e p = 0,0019 para 8h, em comparação com 0h, nos quatro grupos. O LDL-colesterol (p = 0,001) e o HDL-colesterol (p < 0,001) apresentaram decréscimo em todos os tempos após o teste em relação ao basal. Não houve diferença significativa entre os quatro grupos no perfil lipídico após sobrecarga de gordura. A glicemia foi significativamente mais baixa nos grupos DAC e Controle do que nos grupos DM e DM+DAC. Nos grupos DAC e Controle, a glicemia manteve-se inalterada durante o teste. Os grupos DM e DM+DAC apresentaram um decréscimo significativo nos níveis glicêmicos nos tempos 4h, 6h e 8h. (p<0,001 para todos os grupos em relação ao tempo 0h). O comportamento da insulinemia foi semelhante entre os grupos e todos mostraram elevação nos tempos 2h (p<0,001) vs 0h, havendo progressiva queda no decorrer dos tempos, chegando aos níveis basais na oitava hora. A reatividade vascular foi semelhante entre os quatro grupos e não houve diferença nas medidas após sobrecarga. No grupo DM ocorreu uma redução limítrofe na reatividade vascular após a ingestão da sobrecarga lipídica (p = 0,0556). A vasodilatação pós-nitroglicerina também foi semelhante entre os grupos, assim como os resultados obtidos antes e após sobrecarga quando comparados entre si. Este estudo permitiu concluir que a hiperlipemia pós-sobrecarga lipídica nos grupos DAC, DM, DM+DAC e Controle resultou em hiperinsulinemia sem elevação glicêmica, mas sem efeito significativo da reatividade vascular, tanto quando avaliada pela hiperemia reativa (endotélio-dependente), quanto quando estimulada com vasodilatador (endotélio-independente) / To assess the effect of a high-fat meal to simulate to post-prandial state during the day, on the metabolic parameters and endothelial function, four groups of male patients with Coronary Heart Disease and without Diabetes Mellitus (DAC, n= 11); with known Type 2 Diabetes Mellitus and no Coronary Heart Disease (DM, n= 10); and with both Type 2 Diabetes and Coronary Heart Disease (DM+DAC, n = 11) as well as seven healthy controls (Control n = 7) were evaluated before and after receiving a high fat (60g) low carbohydrate (14g) meal test. Lipid profile (basal and 2, 4, 6 and 8 hours after the meal-test) and Vascular reactivity (2, 4 and 8h) were measured. Vascular reactivity was evaluated using high-resolution ultrasound and assessing brachial artery\'s vasodilatory responses during reactive hyperemia (endothelium-dependent vasodilatation), and after nitroglycerin administration, an endotheliumindependent vasodilator. Mean ± SD HbA1c was not significantly by different between groups (DAC: 6.3 ± 0.6% vs DM + DAC: 7.6 ± 1.6% vs DM: 6.8 ± 1,7%) except, as expected in the Control (5.43 ± 0.45%). Furthermore, fasting plasma glucose and insulin were significantly lower in the DAC and Control being however similar in both groups. DAC group had significant by higher uric acid levels than the other three groups (p = 0.025). Post-ischemia brachial artery vasodilation was similar among groups before lipid overload (DAC: 7.44 ± 4.30% vs 7.01 ± 4.53% no DM vs 10.34 ± 5.10% no DM+DAC vs 9.91 ± 2.97% in the Control). Basal change in the brachial artery diameter after sublingual nitrate, performed the day before the fat test, was also within the accepted normal range in all four groups, with no difference in between them (DAC: 19.85 ± 8.66% vs 15.68 ± 11.43 in DM vs 21.24 ± 11.82% in DM+DAC and 20.05 ± 3.73% in the Control). Homeostasis Model for Assessment of insulin sensitivity (HOMAIR) increased significantly and progressively from DAC to DM and to DM+DAC groups, however being significantly lower in the Control. After the fat overload test all four groups had a major increase in triglyceride levels peaking at 4h and 6h after the ingestion (p<0.001) for four groups for 2h, 4h, 6h and 8h vs 0h). Total cholesterol had a increase at all times of sampling (p < 0.001), while LDL-cholesterol (p < 0.001) and HDL-cholesterol (p = 0.001) decreased after the test-meal. Overall, there were no statistical differences among the four groups regarding post load-lipid profile. Glycemia was statistically lower in DAC and Control versus DM and DM+DAC groups. In DAC and Control glicemia was unchanged during testing, DM and DM+DAC groups had a considerable glycemic decrease at times 4h, 6h and 8h after fat-load (p<0.001, for both groups vs 0h). Insulin behaviors was similar among all four groups all of which showed higher levels at 2h (p<0.001 vs 0h, there being a progressive decrease during the test becoming within the basal range at the 8th hour. Vascular reactivity was similar within the four groups and there was no difference through the different measures after fat-loading. In the diabetic group without coronary hearth disease there was a borderline reduction in vascular reactivity after the fat load (p = 0.0556). Vasodilation after nitroglycerin was comparable among the groups again with no differences in the response before and after fat-loading. In conclusion this study showed than the post-load hyperlipemia in DAC,DM, DM+DAC and Control groups resulted in hyperinsulinemia without hyperglycemia and had no significant effects on vascular reactivity both endothelial dependent (hyperemia reactivity) and independent

Objetivo Avaliar, em indivíduos com diabetes (DM), a resposta de glicose e triglicerídeos duas horas após a ingestão de uma carga alimentar (CA) e sua associação com características clínicas e a presença de doenças crônicas. Metodologia Foram incluídos 915 indivíduos com DM, participantes da linha de base do estudo ELSA-Brasil. Coleta de sangue foi realizada em jejum e duas horas após o consumo da CA, contendo 455 kcal; 14 g de gordura saturada e 47 g de carboidratos. Regressão linear foi utilizada para investigar preditores dos níveis de excursão (diferença entre níveis pós-carga e de jejum) de glicemia e trigliceridemia (variáveis dependentes). Regressão logística foi realizada para descrever a associação da excursão de glicemia e trigliceridemia (variáveis independentes) e a presença de complicações do DM (doença coronariana, infarto, angina, acidente vascular cerebral, ou insuficiência cardíaca). Resultados A mediana da glicemia de jejum foi de 150 (123–198) mg/dL e da excursão de glicose foi 45 (16–79) mg/dL, enquanto que a trigliceridemia de jejum foi de 140 (103–199) mg/dL e a excursão de triglicerídeos foi de 26 (11–45) mg/dL. Maiores excursões de glicemia foram associadas com duração do DM (incremento de 5,7 mg/dL, IC95% 3,7–7,6, a cada 5 anos de doença), uso de insulina (58,5 mg/dL, IC95% 45,43–71,55), outro medicamento para DM (13,6 mg/dL, IC95% 2,5–24,8), idade (4,1 mg/dL, IC95% 0,43–7,69, a cada 10 anos), nível de glicose basal (5,2 mg/dL, IC95% 1,0–4,1, a cada 25 mg/dL); o índice de massa corporal associou-se a menor excursão (-6,8 mg/dL, IC95% -9,7 a -3,85, a cada 5 kg/m²). Maior excursão de trigliceridemia esteve associada com glicemia em jejum (2,5 mg/dL, IC95% 1,64–3,38, a cada 25 mg/dL), e menor excursão associada com triglicerídeos de jejum (-2,97 mg/dL, IC95% -3,24 – -2,69, a cada 25 mg/dL). Conclusão A resposta pós-prandial esteve associada ao tempo de doença, à necessidade de insulina ou outro medicamento para DM, ao índice de massa corporal, além da idade e níveis basais de glicose e triglicerídeos. As excursões de glicose e triglicerídeos estiveram associadas a presença de comorbidades potencialmente tidas como complicações do DM. / Objective We aimed to assess, in individuals with diabetes (DM), the excursions of glucose and triglyceride levels two hours after consumption of a food load (FL) and their association with clinical characteristics and the presence of chronic diseases. Design and Methods We included 915 subjects with DM, participants of in the ELSA-Brazil cohort. Blood sampling was performed at fasting and two hours after consumption of a 455 kcal, 14 g saturated fat and 47 g carbohydrate FL. Linear regression was used to investigate predictors of levels of excursion (difference between post-load and fasting levels) of glucose and triglycerides (dependent variables). Logistic regression was performed to describe the association of glucose excursion and triglycerides excursion (independent variables) and the presence of DM complications (coronary heart disease, myocardial infarction, angina pectoris, stroke, or heart failure). Results The median fasting glucose was 150 (123-198) mg/dL and glucose excursion was 45 (16-79) mg/dL, whereas fasting triglycerides was 140 (103-199) mg/dL and triglycerides excursion was 26 (11-45) mg/dL. Increase of glucose excursion were associated with DM duration (increase of 5.7 mg/dL, 95% CI 3.7 to 7.6, each 5 years of disease), insulin use (58.5 mg/dL, 95% CI 45.43 to 71.55), use of another drug for DM (13.6 mg/dL , 95% CI 2.5 to 24.8), age (4.1 mg/dL, 95% CI 0.43 to 7.69, each 10 years), fasting glucose (5.2 mg/dL, 95% CI 1.0 to 4.1, each 25 mg/dL) and body mass index (-6.8 mg/dL, 95% CI -9.7 to -3.85, each 5 kg/m²). The triglycerides excursion was associated with fasting glucose (2.5 mg/dL, 95% CI 1.64 to 3.38, each 25 mg/dL) and fasting triglycerides (-2.97 mg/dL, 95% CI -3.24 to -2.69, each 25 mg/dL). In logistic regression models adjusting for gender, age, fasting glucose, duration of diabetes, use of insulin and/or other drug for DM, the excursion of glucose was marginally associated with the presence of any complication of diabetes and coronary heart disease. Conclusion Greater glycemic postprandial response was positively associated with indicators of less pancreatic reserve and negatively associated with obesity, while and the size of the response in triglycerides presented only minimal associations. Associations of excursion size with diabetes complications were present.

Objetivo. Evaluar el efecto de una bebida alta en fibra a base de linaza, ajonjolí, avena y piña sobre los niveles de triglicéridos en pacientes adultos de un Hospital de Lima Perú. Materiales y método. Ensayo clínico controlado no aleatorizado, se enroló a 60 participantes adultos con diagnóstico de hipertrigliceridemia de un Hospital de Lima-Perú, y se asignó a tres grupos: a un grupo de 23 participantes se le administró una bebida alta en fibras en el hospital, 27 participantes consumieron la bebida alta en fibras en sus casas y a 10 participantes se le prescribió sólo dieta, la bebida y la dieta se administró por 05 días seguidos y se midió los niveles de triglicéridos al inicio y al final de la intervención. Resultados. El 60% fueron del sexo femenino y la edad media 51.11 DS= 13.51, el sexo masculino fue el 40% y la edad media fue 55.29, DS=10.0. El efecto de la bebida alta en fibra fue beneficiosa al reducir significativamente los niveles de triglicéridos en el subgrupo de pacientes que recibió el preparado en el hospital reduciendo los niveles de triglicéridos en 109.87 mg/dL p< 0.05) y en el subgrupo que preparó la bebida en sus casa los niveles de triglicéridos redujeron en 118.48 mg/dL, p< 0.05).En el subgrupo de pacientes que solo recibieron dieta los niveles de triglicéridos también disminuyeron en 80.90 mg/dL con un p<0.05. Cuando se comparó el grupo preparado en hospital y el grupo preparado por ellos mismos hubo (diferencia negativa de 8.6119, un error típico de 20.97, un p valor de 0,911 no significativo) pero con un mejor promedio para aquellos que recibieron la bebida en sus hogares. Conclusión. El efecto de la bebida alta en fibra fue beneficiosa al reducir significativamente los niveles de triglicéridos en el subgrupo de pacientes que recibió el preparado en el hospital y en el grupo que recibió la bebida en sus hogares, pero la diferencia entre ambos grupos no fue significativa. / Objective. To evaluate the effect of a high-fiber drink based on linseed, sesame, oats, and pineapple on triglyceride levels in adult patients at a hospital in Lima, Peru. Materials and methods. Non-randomized controlled clinical trial, 60 adult participants diagnosed with hypertriglyceridemia were enrolled from a hospital in Lima, Peru. They were assigned to three groups: A group of 23 participants was given a high-fiber drink at the hospital, 27 participants consumed the high-fiber drink at home, and 10 participants were prescribed diet only, the drink and diet were administered for 05 consecutive days, and triglyceride levels were measured at the beginning and end of the intervention. Results. 60% (36) were female and the mean age was 51.11 SD=13.51, and 40% (24) were male and the mean age was 55.29, SD=10.0. The effect of the high-fiber drink (based on linseed, sesame, oats, and pineapple) was beneficial in significantly reducing triglyceride levels by 109.87 mg/dL p<0.05 in the subgroup of patients who received the preparation at the hospital, and by 118.48 mg/dL, p<0.05 in the subgroup of patients who prepared the drink at home. In the subgroup of patients who only received diet, triglyceride levels also decreased by 80.90 mg/dL with a p<0.05. When comparing the group who received the preparation at the hospital and the group who prepared the drink themselves, there was a negative difference of 8.6119, a typical error of 20.97, a non-significant p-value of 0.911, but a better average for those who received the drink at home. Conclusion. The effect of the high-fiber drink was beneficial in significantly reducing triglyceride levels in the subgroup of patients who received the preparation at the hospital and in the group of patients who received the drink at home, but the difference between the two groups was not significant. / Tesis

L’hypertriglycéridémie (hyperTG) est une dyslipidémie fréquente, caractérisée par une augmentation de la concentration plasmatique en triglycérides (TG). L’hyperTG est considérée comme un facteur de risque indépendant de la maladie cardiovasculaire, particulièrement de la maladie coronarienne athérosclérotique. Plusieurs facteurs environnementaux et génétiques ont été associés avec l’hyperTG. Cependant, près de 90% des cas d’hyperTG primaire sont encore incomplètement caractérisés au niveau moléculaire. Dernièrement, la protéine GPIHBP1 (glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1), qui a un rôle clef dans le métabolisme des TG, a été associée à l’expression d’hyperTG sévère et rare chez l’humain. Ce mémoire présente les résultats de nos travaux qui ont été effectués afin d’identifier de nouvelles bases moléculaires associées à l’expression de l’hyperTG dans le locus du gène GPIHBP1. Nous avons observé que le polymorphisme GPIHBP1 g.-469G>A (rs72691625), dont la fréquence de l’allèle mineure a été évaluée à 19,6% dans notre échantillon, serait associé à l’expression d’hyperTG (TG ≥ 2mmol/L) dans une population canadienne-française. Ce polymorphisme est associé à un risque 1,67 fois plus grand d’exprimer une triglycéridémie ≥ 2mmol/L chez les porteurs hétérozygotes et 5,7 fois plus grand chez les porteurs homozygotes, comparativement aux non-porteurs. Ce risque d’hyperTG serait exacerbé par la présence concomitante d’une mutation hypertriglycéridémiante dans le gène codant pour la lipoprotéine lipase. La présence de ce polymorphisme serait particulièrement associée à l’expression de la dysbêtalipoprotéinémie familiale et de l’hypertriglycéridémie familiale endogène. GPIHBP1 g.-469G>A est le premier polymorphisme fréquent identifié dans le promoteur du gène à être associé avec l’expression d’hyperTG. GPIHBP1 émerge de plus en plus comme un gène candidat intéressant pour la recherche de nouvelles bases moléculaires pouvant expliquer certaines formes d’hyperTG primaire fréquente. / Hypertriglyceridemia (hyperTG) is a frequent dyslipidemia referring to an increased fasting plasma triglyceride (TG) level ≥ 2 mmol/L. HyperTG is an independent risk factor for cardiovascular disease, such as coronary artery diseases. Several environmental and genetic factors have been associated with hyperTG. Although several gene factors were associated with hyperTG, nearly 90% of cases of primary hyperTG are still incompletely characterized at the molecular level. Recently, few cases of rare and severe hyperTG have been associated with some rare polymorphisms in the gene coding for GPIHBP1 (glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1). This manuscript resumes our research regarding the identification of new molecular bases associated with the expression of frequent hyperTG subtypes in the gene locus GPIHBP1. Our results show that the GPIHBP1 g.-469G>A polymorphism (rs72691625), whose the minor allele frequency was estimated to 19.6% in our sample, was associated with the expression of hyperTG (TG ≥ 2 mmol/L) in a French-Canadian population. Subjects heterozygous and homozygous for this polymorphism respectively had a 1.67-fold and 5.70-fold increased risk to exhibit plasma TG levels ≥ 2mmol/L as compared to non-carriers. This increased risk of hyperTG observed in g.-469A carriers seems to be exacerbated by the concomitant presence of a frequent loss-of-function lipoprotein lipase gene variant. This polymorphism seems also particularly associated with dysbetalipoproteinemia and familial hypertriglyceridemia. The g.-469G>A polymorphism is the first common polymorphism in the GPIHBP1 gene promoter to be associated with the expression of hyperTG. GPIHBP1 emerges as a significant candidate for the molecular based of primary hyperTG.

L’hypertriglycéridémie (HTG) correspond à une accumulation des lipoprotéines riches en triglycérides (LRTG) dans la circulation plasmatique, conséquence d’une augmentation de leur synthèse ou plus classiquement décrit, d’une diminution de leur catabolisme. Dans près de 50% des cas, aucune cause génétique n’est identifiée chez les patients présentant une présentant une HTG sévère, aussi bien dans le cadre du syndrome de chylomicronémie familiale (FCS) que dans celui du syndrome de chylomicronémie multifactorielle (MCS). Pour améliorer nos connaissances et la caractérisation de ces patients, la conduction de corrélations phénotypes-génotypes précises grâce à une collaboration clinico-biologique étroite, ainsi que le développement d’outils de diagnostic moléculaire performants, demeurent un enjeu majeur. Premièrement, l’évaluation de la concentration pré-héparinique en LPL et l’activité post-héparinique 60 minutes après l’injection d’héparine chez 62 patients MCS caractérises génétiquement a permis la mise en évidence deux sous-groupes chez ces patients. Deuxièmement, le développement d’une stratégie séquençage de nouvelle génération permettant d’explorer simultanément les 9 gènes les plus prévalents dans les hypercholestérolémies, les hypocholestérolémies et les hypertriglycéridémies, a permis de détecter les variants nucléotidiques avec une sensibilité équivalente au séquençage Sanger mais aussi de détecter des grands réarrangements. L’ensemble des résultats souligne la complexité des mécanismes de régulation du métabolisme des LRTG et l’intérêt de l’étude des interactions gène-gène. Ainsi, ces travaux ont permis de mettre en évidence de nouvelles hypothèses à explorer pour la compréhension des mécanismes physiopathologiques des HTG sévères et d’améliorer les outils disponibles pour les études de corrélation génotype-phénotype / Hypertriglyceridemia (HTG) correspond to an increase of triglyceride-rich lipoproteins (TGRL) circulating concentration, as a consequence of an increase in the synthesis of or a decrease in their catabolism, most classically described. In nearly 50% of patients with severe hypertriglyceridemia (HTG), no genetic cause is identified, either in familial chylomicronemia syndrome (FCS) or in multifactorial chylomicronemia syndrome (MCS). To gain new insights and to improve patient’s characterization, it remains important to conduct accurate phenotype-genotype association studies through close collaboration with referent lipidologists, and to develop high-performance tools for molecular diagnosis. Firstly, the assessment of pre-heparin LPL concentration as well as LPL activity 60 minutes after heparin injection, enabled the identification of two subgroups within 62 genotyped MCS patients Secondly, the development of a new sequencing generation workflow exploring simultaneously the 9 most prevalent genes in dyslipidemia, allowed the detection of single nucleotide variations with sensitivity equivalent to Sanger sequencing, but also allowed the detection of copy number variations. Collective consideration of the results underlines the complexity of the regulation mechanisms of TGRL metabolism and the interest of gene-gene interactions study. Thus, the studies presented herein bring new hypothesis to explore for understanding the pathophysiological mechanisms of severe HTG and to improve molecular diagnosis tools available for phenotype-genotype association studies