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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.
91

Avaliação do efeito do pó liofilizado da casca de jabuticaba (Myrciaria jaboticaba (Vell.) Berg) sobre o estresse oxidativo, tratamento da obesidade e parâmetros de saúde in vivo / Effect of freeze-dried jaboticaba (Myrciaria jaboticaba (Vell.) Berg) peel on oxidative stress, treatment of obesity and health parameters in vivo

Lenquiste, Sabrina Alves, 1987- 19 August 2018 (has links)
Orientador: Mario Roberto Marostica Júnior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-19T17:44:21Z (GMT). No. of bitstreams: 1 Lenquiste_SabrinaAlves_M.pdf: 1146475 bytes, checksum: 3b7f25b2155d7b54ff4652b672de9aff (MD5) Previous issue date: 2012 / Resumo: O objetivo do presente estudo foi avaliar o efeito da casca de jabuticaba liofilizada (CJL) adicionada à dieta hiperlipídica no desenvolvimento da obesidade, perfil lipídico e hormonal e resistência à insulina, bem como sobre a peroxidação lipídica e modulação das enzimas com atividade antioxidante. Para tanto, ratos Sprague-Dawley foram alimentados com dieta Controle, dieta hiperlipídica (HF) e dietas HF adicionadas de 1, 2 e 4% de CJL. Ingestão energética, ganho de peso e composição corporal, além de glicose sérica e perfil lipídico e hormonal foram determinados. A resistência à insulina (RI) foi determinada pelo Teste de Tolerância à Glicose (GTT), Teste de Tolerância à Insulina (ITT) e cálculo do indicador de HOMA-IR. Para avaliar o status antioxidante, os níveis de TBARS e isoprostanos, bem como as concentrações de glutationa total, glutationa redutase, glutationa peroxidase, catalase e superóxido dismutase foram mensuradas no plasma dos animais. No tecido hepático, foram mensurados os níveis de TBARS e hidroperóxidos. Todos os resultados foram submetidos ao teste estatístico de ANOVA e teste de Tukey (p<0,05). A CJL adicionada à dieta HF não reverteu o ganho de peso e não alterou o colesterol total, perfil hormonal e glicose sérica. Contudo, o consumo de 1, 2 e 4% de CJL reduziu significativamente a insulina sérica e o indicador de HOMA-IR nos animais experimentais. Além disso, os animais alimentados com 2% de CJL mostraram níveis de HDL-colesterol similares ao grupo Controle (aumento de 41,65% comparado com o grupo HF). No status antioxidante, a CJL adicionada à dieta HF não reverteu a peroxidação lipídica no plasma e fígado dos animais. Porém, os níveis das enzimas glutationa redutase, catalase e superóxido dismutase foram aumentadas no plasma dos animais. Assim, o consumo de CJL pode promover aumento do HDL-colesterol, melhorar a RI e modular positivamente a atividade dessas enzimas, promovendo aumento no potencial antioxidante e prevenindo o desenvolvimento de doenças cardiovasculares, diabetes melitos tipo 2 e outras doenças relacionadas com o estresse oxidativo / Abstract: The objective of this study was to evaluate the effect of freeze-dried jaboticaba peel (FJP) added to high-fat diet on the development of obesity, lipid and hormonal profile and insulin resistance, as on lipid peroxidation and modulation of enzymes with antioxidant activity. For this purpose, Sprague-Dawley rats were fed a control diet, high-fat control diet and high-fat diets added to 1, 2 and 4% of FJP. Energy intake, weight gain and body composition, as serum glucose, lipid and hormonal profile were determined. The Insulin Resistance (IR) was determined by glucose tolerance test (GTT), insulin tolerance test (ITT) and calculation of HOMA-IR index. To evaluate the antioxidant status, the levels of TBARS and isoprostane, well as the concentrations of total glutathione, glutathione reductase, glutathione peroxidase, catalase and superoxide dismutase were measured in plasma of animals. Levels of TBARS and hydroperoxides were measured in liver tissue. All results were submitted to statistical analysis ANOVA and Tukey's test (p<0.05). The FJP added to the diet did not reverse the weight gain and did not alter the total cholesterol, hormonal profile and serum glucose. However, consumption of 1, 2 and 4% FJP reduced serum insulin and HOMA-IR index of the experimental animals. In addition, animals fed with 2% FJP showed HDL-cholesterol levels similar to control group (increase 41.65% compared to HF group). In antioxidant status, the FJP added to HF diet did not reverse the lipid peroxidation in plasma and liver of animals. However, the levels of enzymes glutathione reductase, catalase and superoxide dismutase were increased in plasma of animals. Thus, the consumption of FJP can increases HDL-cholesterol, improvement insulin resistance and modulate positively the activity these enzymes, promoting an increase in antioxidant potential and preventing the development of cardiovascular diseases, type 2 diabetes mellitus and other diseases related with oxidative stress / Mestrado / Nutrição Básica Experimental e Aplicada à Tecnologia de Alimentos / Mestre em Alimentos e Nutrição
92

Análise do perfil metabólico e cardiovascular de ratos alimentados com dieta hiperlipídica por quatro semanas / Metabolic and cardiovascular analysis in rats fed with high-fat diet during four weeks

Crege, Danilo Roberto Xavier de Oliveira, 1981- 20 August 2018 (has links)
Orientador: Dora Maria Grassi Kassisse / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T10:02:32Z (GMT). No. of bitstreams: 1 Crege_DaniloRobertoXavierdeOliveira_D.pdf: 1062657 bytes, checksum: 6d99ee0443e8bca419a135928e80df63 (MD5) Previous issue date: 2012 / Resumo: A mudança no estilo de vida, principalmente por conta do sedentarismo e da ingestão de dietas com grandes quantidades calóricas, tem aumentado significativamente a prevalência de doenças crônico-degenerativas na população. Diversas pesquisas mostram que a obesidade é responsável por predispor uma grande variedade de distúrbios metabólicos que muitas vezes aparecem combinados levando a chamada síndrome metabólica. A síndrome metabólica é caracterizada pela presença de um grupo de fatores de risco como obesidade central, resistência à insulina, aumento da pressão arterial e esteatose hepática. Nosso laboratório realiza desde 1996, estudos envolvendo a utilização de dietas hiperlipídicas e as implicações nestes tecidos, a fim de contribuir para o esclarecimento de como cardiopatias e alterações metabólicas são instaladas nestes modelos. O objetivo deste trabalho foi avaliar as alterações metabólicas e cardiovasculares em ratos submetidos ao tratamento com dieta hiperlipídica por quatro semanas e comparar com outros modelos estudados no laboratório. Para análise das alterações metabólicas nos ratos que fizeram ingesta da dieta hiperlipídica foram utilizadas técnicas de: clamp euglicêmicohiperinsulinêmico, isolamento de adipócitos do panículo epididimal para verificação da captação de glicose e produção de lactato e glicerol, além da análise morfométrica destes adipócitos. A análise das alterações cardiovasculares foi realizada utilizando parâmetros eletrocardiográficos e procedimentos de histologia cardíaca. Nossos resultados mostraram que ratos, que fizeram ingesta da dieta hiperlipídica por quatro semanas, apresentaram resistência à insulina verificada pela redução na taxa de infusão de glicose durante o clamp euglicêmico-hiperinsulinêmico. Além disso, a captação de glicose pelos adipócitos isolados da região epididimal também foi significativamente menor. A redução na captação de glicose, provavelmente, foi responsável pela diminuição na produção de lactato por estes adipócitos isolados dos ratos hiperlipidêmicos. A lipólise basal não foi alterada, entretanto, a estimulada por agonistas adrenérgicos apresentou-se diminuída, sendo que estas alterações não comprometeram a morfometria dos adipócitos epididimais. Os ratos dislipidêmicos também apresentaram alterações cardíacas, como a hipertrofia, avaliada pela análise histológica do coração. Estes resultados demonstram que a ingesta de dieta hiperlipídica por quatro semanas é capaz de promover alterações metabólicas, sugerindo instalação do quadro de resistência à insulina, sem causar alterações na glicemia, além de levar a hipertrofia cardíaca, sendo, portanto, um modelo útil para o estudo de complicações iniciais decorrentes da ingestão de dieta hiperlipídica / Abstract: Changes in lifestyle, especially due to sedentarism and intake of high caloric diets have significantly increased the prevalence of chronic diseases in the population. Many researches show that obesity is responsible to a huge variety of metabolic disorders that usually appears combined leading to a disease known as the metabolic syndrome. Metabolic syndrome is characterized by the presence of a group of risk factors such as central obesity, insulin resistance, increase in blood pressure and hepatic steatosis. Our laboratory conducts, since 1996, studies involving the use of high-fat diet and the implications in these tissues in order to contribute to the comprehension of how cardiopathies and metabolic disorders are installed in these models. The aim of this study was to evaluate the metabolic and cardiovascular disorders in rats fed with highfat diet during four weeks and to compare this information with other models used in our laboratory. To analyze the metabolic changes in rats that were fed with high-fat diet, we used the following techniques: euglycemic-hyperinsulinemic clamp, adipocytes isolation from epididymal panniculus, for the verification of glucose uptake, lactate and glycerol production, besides morphometric analysis of these adipocytes. The analyses of cardiovascular disorders were performed using electrocardiographic parameters and cardiac histology procedures. Our results demonstrated that, rats, fed with high-fat diet during four weeks showed insulin resistance, verified by reduction in the rate of glucose infusion, during euglycemic-hyperinsulinemic clamp. In addition, glucose uptake by isolated adipocytes from epididymal tissue was significantly lower. The reduction in glucose uptake probably was the responsible for diminish lactate production by these isolated adipocytes of hyperlipidemic rats. Basal lipolysis was not altered, however, the one stimulated by adrenergic agonists was reduced, and these changes did not affect the morphometry of epididymal adipocytes. The dislipidemic rats also showed cardiac alterations, such as hypertrophy, observed in a hystologic analyses of the heart. These results demonstrate that the intake of high-fat diet during for weeks is able to promote metabolic disorders, suggesting insulin resistance development, however, without promotes glycemic alterations, besides leads to cardiac hypertrophy, and is therefore, a useful model to study these initial complications resulting from the ingestion of high-fat diet / Doutorado / Fisiologia / Doutor em Biologia Funcional e Molecular
93

Expressão de enzimas envolvidas na produção de triacilglicerol em tecidos adiposo e hepático isolados de ratos normo e hiperlipidêmicos / Expression of enzymes involved in the production of triacylglycerol in adipose and liver isolated tissue from normo and hyperlipidemic rats

Bellenzani, Marcela Palomo Pieroni, 1984- 20 August 2018 (has links)
Orientador: Dora Maria Grassi Kassisse / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-20T14:23:50Z (GMT). No. of bitstreams: 1 Bellenzani_MarcelaPalomoPieroni_M.pdf: 6472856 bytes, checksum: e473a96a17b23ee1d9a456d9ac7a4602 (MD5) Previous issue date: 2012 / Resumo: A pandemia da obesidade é evidente no início do século XXI. O fator desencadeante mais relevante é a alimentação hipercalórica associada ao sedentarismo. Modelos de estudo em ratos para investigar as etapas que precedem o desenvolvimento desta doença são fundamentais para propor terapias de prevenção. No modelo de indução da dislipidemia pela dieta por quatro semanas, os ratos apresentam hipercolesterolemia, hipertrigliceridemia e hiperinsulinemia e com seis semanas de administração da dieta observa-se um aumento no peso dos panículos adiposos da região epididimal e peri-renal e sem alteração no depósito da região mesentérica. Assim sendo, objetivamos, nesta tese, analisar as vias metabólicas envolvidas no processo de metabolização da glicose e triacilgliceróis nos tecidos adiposo branco e hepático em ratos hiperlipidêmicos e para tal estudamos as vias lipogênica, lipolítica e neoglicogênica, pela quantificação da expressão gênica das enzimas chaves envolvidas nestes processos. A dislipidemia foi induzida pelo oferecimento de dieta hiperlipídica (grupo dieta, D) ao longo de quatro semanas a ratos jovens e a instalação do quadro foi verificada pelas análises plasmáticas ao final do tratamento e após jejum de 16h. Amostras de tecidos hepático e adiposo foram coletadas para análise histológica e quantificação da expressão gênica sendo estas analisadas por qRT-PCR. Observou-se que ratos que ingerem dieta hiperlipídica (+129+10,13 g) ganham peso de forma semelhante aos ratos controle (C: +148+8,8 g) mesmo ingerindo quantidade significativamente menor de dieta (C: 20,8+0,62 g vs D: 14,87+0,66 g). As análises histológicas ilustram aumento no teor de depósitos de lipídeos no tecido hepático. A expressão gênica no tecido hepático de ratos dieta foi aumentada significativamente para as enzimas lipoproteína lipase, piruvato desidrogenase quinase 4 e fosfofrutoquinase 1 e diminuição significativa na expressão de glicose 6-fosfatase sem alteração na quantificação da expressão de acetil-CoA carboxilase alpha, gliceroquinase, piruvato desidrogenase fosfatase 2. Em relação ao tecido adiposo observamos que a expressão das enzimas acetil-CoA carboxilase e piruvato desidrogenase fosfatase 2 não foi significativamente alterada em nenhum dos depósitos adiposos. A lipase hormônio-sensível não apresentou alterações no tecido adiposo epididimal, porém teve sua expressão significativamente aumentada nos tecidos mesentérico e peri-renal. A expressão da lipoproteína lipase por sua vez, não se alterou no panículo adiposo epididimal nem no panículo adiposo mesentérico estando diminuída no panículo adiposo peri-renal. E por fim, a piruvato desidrogenase quinase 4 também não apresentou alterações nos depósitos epididimal e mesentérico porém no peri-renal sua expressão encontrou-se aumentada. Estes resultados, em conjunto, indicam que a dieta administrada por 4 semanas, mesmo não apresentando todas as alterações observadas com 6 semanas, pode ser útil para os estudos iniciais do quadro de dislipidemia que antecedem as disfunções metabólicas / Abstract: The pandemic of obesity is evident in the twenty-first century. The most important and triggering factor is the high-calorie diet associated with physical inactivity. Study models in rats to investigate the steps that precede the development of this disease are essential to propose preventive therapies. In the model of induction of dyslipidemia by diet for four weeks, the mice exhibit hypercholesterolemia, hypertriglyceridemia, and hyperinsulinemia and there is an increase in weight of the panniculus region of epididymal and peri-renal depot and no change in the mesenteric region. Therefore, we aimed to analyze the metabolic pathways involved in the metabolism of glucose and triglycerides in white adipose tissue, and liver in hyperlipidemic rats and to study the ways that lipogenic, lipolytic and glyconeogenic for the quantification of gene expression of key enzymes involved in these processes. Dyslipidemia was induced by offering high-fat diet (diet group, D) over four weeks to young rats and onset of condition was verified by analysis at the end of the plasma treatment and after fasting for 16 hours. Samples of liver and adipose tissue were collected for histological analysis and quantification of gene expression and these were analyzed by qRT-PCR. It was observed that mice eat high-fat diet (+129 +10.13 g) gain weight similarly to control rats (C: +8.8 +148 g) even eating significantly less diet (C: 20.8 +0.62 g vs D: 14.87 +0.66 g). Histological analysis illustrate the content of lipid deposits in liver tissue. Gene expression in liver tissue of rats diet was significantly increased for the enzymes lipoprotein lipase, pyruvate dehydrogenase kinase 4 and 1 and Phosphofructokinase significant decrease in the expression of glucose 6-phosphatase no change in the quantification of the expression of acetyl-CoA carboxylase alpha, Gliceroquinase, pyruvate dehydrogenase phosphatase 2. In relation to the adipose tissue we observed that the expression of the enzyme acetyl-CoA carboxylase and pyruvate dehydrogenase phosphatase 2 was not significantly altered in any of the fatty deposits. The hormone-sensitive lipase showed no changes in epididymal adipose tissue but its expression was significantly increased in mesenteric tissue and peri-renal. Lipoprotein lipase, in turn, did not change in the mesenteric or epididymal being reduced in the peri-renal. And finally, the pyruvate dehydrogenase kinase 4 also showed no changes in epididymal and mesenteric but the peri-renal expression is increased. These results, together, indicate that the diet for 4 weeks, even not showing all changes observed within 6 weeks, can be useful for the initial studies of hyperlipidemia that precede the metabolic dysfunctions / Mestrado / Fisiologia / Mestre em Biologia Funcional e Molecular
94

Efeito do consumo de bebidas ricas em polifenóis sobre a função e integridade do tecido hepático de ratos alimentados com dieta hiperlipídica

Bedê, Teresa Palmisciano 28 March 2017 (has links)
Submitted by Biblioteca da Faculdade de Farmácia (bff@ndc.uff.br) on 2017-03-28T17:01:20Z No. of bitstreams: 1 Bedê, Teresa Palmisciano [Dissertação, 2015].pdf: 1365884 bytes, checksum: 2fb9e05630c2ebc5ce56e4099bbd7366 (MD5) / Made available in DSpace on 2017-03-28T17:01:20Z (GMT). No. of bitstreams: 1 Bedê, Teresa Palmisciano [Dissertação, 2015].pdf: 1365884 bytes, checksum: 2fb9e05630c2ebc5ce56e4099bbd7366 (MD5) / Introdução: A busca da população por melhor qualidade de vida contribui para os estudos acerca de alimentos com propriedades funcionais e de prevenção de doenças. Destacam-se o suco de uva tinto integral (SUTI) e o vinho tinto (VT) que, ricos em polifenóis, vem demonstrando potente ação antioxidante e antinflamatória. Objetivo: Avaliar os efeitos do consumo de SUTI, de VT e de solução de resveratrol (SR) sobre a função e integridade hepática de ratos alimentados com dieta hiperlipídica. Materiais e Métodos: Foi realizado ensaio biológico com 50 Rattus Novergicus Wistar Albino, fêmeas adultas, divididas em 5 grupos: controle (GC)- ração caseína + água; hiperlipídico (GH)- ração hiperlipídica + água; vinho tinto (GV)- ração hiperlipídica + 10mL/dia de VT; suco de uva (GS)- ração hiperlipídica + 15mL/dia de SUTI e, resveratrol (GR)- ração hiperlipidica + 15mL/dia de SR. Durante 60 dias, ração e água foram ofertados em livre demanda e o peso corporal, o consumo alimentar e a pressão arterial foram verificados e registrados. Ao final do estudo, os animais foram sacrificados, amostras de sangue foram coletadas para análises bioquímicas e o fígado foi retirado para avaliações histológicas. Para comparação das médias entre grupos foi utilizado Anova one-way e Tukey como pós-teste, considerando um nível de significância de 5%. Resultados: A concentração de polifenóis totais (mg EAG -1) e de trans-resveratrol (mg/L) foi menor (p<0,05) no SUTI do que nas demais bebidas, mas a capacidade antioxidante não diferiu entre elas. Não houve diferença no peso corporal e no consumo alimentar dos grupos. A pressão arterial sistólica (mmHg) foi menor (p<0,05) no GS e GC. O GH apresentou maior (p<0,05) variação de glicemia (mg/dL) e o GR foi o único que apresentou diminuição de glicemia ao longo do estudo. A concentração (mg/dL) de colesterol total foi menor (p<0,05) no GS do que no GC, mas não houve diferença na concentração (mg/dL) de lipoproteína de alta densidade – HDL e, a concentração (mg/dL) de triglicerídeos foi maior (p<0,05) no GC. Não houve diferença na concentração (U/L) de aspartatotransaminase, mas o GS foi o único que apresentou-se dentro do intervalo de normalidade. Todos tiveram concentração (U/L) de alaninatransaminase acima do recomendado, mas o GS apresentou concentração numericamente menor e, a concentração de fosfatase alcalina (U/L) do GR foi menor (p<0,05) do que o GH e GV. A concentração de interleucina 6 (pg/mL) foi menor (p<0,05) no GS do que no GV. O peso do fígado (g/100gPC) foi semelhante entre os grupos, mas a concentração de gordura hepática (g%) foi menor (p<0,05) no GS e GC, e o teor de proteínas no fígado (g%) do GS foi menor (p<0,05) do que no GV e GR. A área dos núcleos dos hepatócitos (μm²) foi menor (p<0,05) no GC do que no GH, GV e GS, mas o IOD mostrou-se menor (p<0,05) no grupo GC, seguido pelo GS e maior no GH e GV. Conclusões: O consumo de SUTI parece ser capaz de minimizar os efeitos da dieta hiperlipídica sobre o tecido hepático. Mesmo diante do menor teor de polifenóis, o SUTI pode ter conferido proteção sobre certos parâmetros bioquímicos avaliados, assim como sobre o desenvolvimento de hipertensão arterial e da doença hepática gordurosa não alcoólica, o que não foi observado com o VT e a SR / Introduction: The search for people for better quality of life contributes to the studies of food with properties functional and disease prevention. Stand out from the full red grape juice (JG) and red wine (RW) that are rich in polyphenols, has demonstrated potent antioxidant action and antinflammatory. Objective: To evaluate the effects of consumption of JG, RW and resveratrol solution (SR) on liver function and integrity of mice fed high-fat diet. Materials and Methods: This was a biological assay with 50 Rattus Novergicus Wistar Albino adult females divided into 5 groups: control (GC) - casein diet + water; hyperlipidic (GH) - fat diet + water; red wine (GW) - fat diet + 10 mL of RW / day; juice (GJ) - fat diet + 15mL of JG / day and resveratrol (GR) - fat diet + 15 mL of SR / day. During 60 days, feed and water were offered on free demand and, body weight, food intake and blood pressure were checked and recorded. At the end of the study, the animals were sacrificed, blood samples were collected for biochemical analysis and the liver was removed for histological evaluation. To compare the means between groups we used one-way ANOVA and Tukey as post-test, considering a 5% significance level. Results: The concentration of total polyphenols (mg EAG -1) and trans-resveratrol (mg/ L) was lower (p<0.05) in JG than the other drinks, but the antioxidant capacity did not differ between them. There was no difference in body weight and food consumption groups. Systolic blood pressure (mmHg) was lower (p<0.05) in the GJ and GC. GH had higher (p<0.05) blood glucose change (mg/ dL), and GR is the only one that decreases in blood glucose throughout the study. Concentration (mg / dL) of total cholesterol was lower (p<0.05) in GJ than in the GC, but there was no difference in the concentration (mg/ dL) of high-density lipoprotein - HDL and the concentration (mg/ dL) triglyceride was higher (p<0.05) in GC. There was no difference in the concentration (U/L) aspartatotransaminase, but the GJ was the one who introduced himself within normal range. All had concentration (U/L) alaninatransaminase above recommended, but the GJ presented numerically lowest concentration, and the concentration of alkaline phosphatase (U/L) of GR was smaller (p<0.05) than GH and GW. The concentration of interleukin-6 (pg/mL) was lower (p<0.05) in GJ than in the GW. Liver weight (g /100g body weight) was similar between the groups, but the concentration of liver fat (g%) was lower (p<0.05) in the GJ and GC, and the protein content in the liver (g%) GJ was lower (p <0.05) than the GW and GR. The area of the nuclei of hepatocytes (μm²) was lower (p<0.05) in the GC than in the GH, GW and GJ, but the IOD was lower (p <0.05) in the GC, followed by GJ and higher in GH and GW. Conclusions: Consumption of JG seems to be able to minimize the effects of high fat diet on liver tissue. Even with the lower polyphenol content, the JG may have conferred protection on certain biochemical parameters, as well as on the development of hypertension and non-alcoholic fatty liver disease, which was not observed with RW and SR
95

Effect of a high fat diet on a mouse model of Alzheimer's disease

Knight, Elysse January 2011 (has links)
Alzheimer's disease (AD) is a progressive neurodegenerative disorder, characterised by deficits in language, behaviour and memory. Increasing evidence suggests that mid-life obesity and a diet high in fat are risk factors for AD. In contrast, life-threatening weight loss occurs and worsens as the disease progresses, despite adequate or increased food intake. A greater understanding of energy balance in AD may therefore uncover novel targets for therapy. The aim of this thesis was to test the hypothesis that 3xTgAD mice display altered energy balance and that experimental changes to this balance will alter cognition. To address this hypothesis, three key objectives were set up; to characterise the energy balance profile, characterise behaviour and memory, and evaluate the response to an high fat (HF) diet in a triple transgenic (3xTgAD) model, an experimental mouse model of AD. Energy balance was characterised in non-transgenic (Non-Tg) control and 3xTgAD mice, demonstrating altered body weight, food intake and metabolic rate in the 3xTgAD mouse model of AD. At 2-month of age male 3xTgAD mice displayed greater food intake and body weight, but no difference in metabolic rate, whereas from 12 months of age 3xTgAD mice weighed less, despite eating more, and had a higher metabolic rate than Non-Tg control mice. This provides evidence that there is a shift towards a hypermetabolic state from 12 months of age in 3xTgAD mice, which may represent a key stage in advancement of the disease process. Behaviour and memory were characterised in Non-Tg control and 3xTgAD mice in a battery of tests at different ages. 3xTgAD mice showed changes in open-field activity/anxiety from 3 months of age. Memory impairments were first detected in 3xTgAD mice at 3 months of age as deficits in odour recognition memory, mirroring early impairments seen in AD patients. Deficits in spatial memory were then observed in both the Y-maze spontaneous alternation and Morris water maze tests from 5 months of age. Finally, deficits in non-spatial visual object memory were observed in 3xTgAD mice in the novel object recognition test at 8 months of age. Energy balance, behaviour and memory were assessed in Non-Tg control and 3xTgAD mice in response to an HF diet. Non-Tg control and 3xTgAD mice displayed similar energy balance profiles in response to an HF diet. The HF diet was found to worsen memory in Non-Tg mice in odour recognition at 3-4 and 7-8 months of age, in the Morris water maze at 7-8 months of age and in novel object recognition and spontaneous alternation at 11-12 and 15-16 months of age. Similarly, the HF diet worsened memory in 3xTgAD mice in odour discrimination at 3-4 and 7-8 months of age, the Morris water maze at 7-8 and 11-12 months of age, and in spontaneous alternation at 15-16 months of age. As an HF diet induced memory impairments, in both Non-Tg control and 3xTgAD mice, it suggests that diet-induced deficits may therefore, not be specific to AD, but rather to cognition in general. Overall, these data demonstrate that 3xTgAD mice show AD-like age-dependent changes in energy balance, behaviour and memory. Furthermore, an HF diet produced impairments in memory in 3xTgAD mice, but these effects were not specific to AD, as an HF diet also led to deficits in control animals. These data support a role for energy balance in the progression of AD, although the underlying mechanisms remain poorly understood. 3xTgAD mice may therefore represent a good model to examine energy balance during AD and to evaluate targets for future therapies.
96

Effects of a high-fat diet in health and in Alzheimer's disease : a gender comparison study

Antunes Martins, Isaura January 2015 (has links)
The prevalence of obesity is growing worldwide partly due to an increase in consumption of diets high in fat. Obesity is known as a risk factor for developing Alzheimer’s disease (AD) later in life. Both obesity and AD are associated with cognitive deficits and experimental high-fat diets can impair memory in cognitively normal rodents but also worsen memory deficits in AD mouse models. What is still unclear is the molecular mechanisms behind the detrimental effects of a high-fat diet on memory and if sex can influence its effect. Data in this thesis demonstrated that compared to females, male control non-transgenic (Non-Tg) mice had earlier deficits in memory after a high-fat diet that were associated with hyperinsulinemia. However, female Non-Tg mice were more vulnerable to ultrastructural changes in mitochondria morphology and loss of synapses after 6 months of a high-fat diet, changes that were similar to those observed in control-fed female triple-transgenic mice (3xTgAD). Finally, the memory deficits observed after a high-fat diet in cognitively normal mice were not associated with obesity and adiposity, as treatment with resveratrol (RSV) an anti-obesogenic compound, attenuated body weight gain and adipose tissue but failed to reverse memory impairment. In control fed 3xTgAD mice, RSV rescued memory deficits. In all experiments a high-fat diet had no detectable effect on cognitive impairment in 3xTgAD mice. In conclusion, the present thesis demonstrates that the sex-dependent differences in the effect a high-fat diet on memory are likely due to hyperinsulinemia and mitochondrial impairment and do not depend on obesity phenotype. These results demonstrate the importance of gender when studying both obesity and AD and are relevant for future clinical trials.
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Dieta hiperlipídica, inflamação e programação metabólica : efeitos na sinalização de insulina em camundongos recém-desmamados e adultos / High-fat diet, inflammation and metabolic programming : effects on insulin signaling in newly weaned and adult offspring of mice

Fante, Thaís de, 1990- 27 August 2018 (has links)
Orientadores: Adriana Souza Torsoni, Marciane Milanski / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Aplicadas / Made available in DSpace on 2018-08-27T16:45:13Z (GMT). No. of bitstreams: 1 Fante_Thaisde_M.pdf: 3029616 bytes, checksum: 5e68ab17d3076784e4f20c127d76838f (MD5) Previous issue date: 2015 / Resumo: O estilo de vida moderno tem levado ao aumento na prevalência de obesidade e suas co-morbidades em gestantes e na população cada vez mais jovem. Muitos dos efeitos do consumo direto de dieta hiperlipídica (DH) no metabolismo de glicose e lipídios já são bem estabelecidos. No entanto, considera-se importante avaliar se o consumo de DH durante períodos críticos do desenvolvimento seria capaz de ativar mecanismos epigenéticos, perpetuando mudanças no metabolismo da prole e criando um ciclo vicioso que não poderia ser interrompido. O objetivo desse estudo foi avaliar o efeito potencial da programação metabólica em prejudicar a sinalização de insulina na prole recém desmamada de mães alimentadas com dieta hiperlipídica durante a gestação e lactação. Além disso, investigamos se a exposição precoce a um ambiente obesogênico seria capaz de exacerbar o prejuízo no metabolismo de glicose na vida adulta de animais reexpostos à dieta hiperlipídica. Para isso, camundongos fêmeas da linhagem Swiss foram alimentados com dieta controle ou DH durante os períodos de adaptação, gestação e lactação, e os tecidos da prole macho foram analisados nos dias 28 e 82. Os resultados mostram que a prole de mães obesas (HC-O) apresentou maior ganho de peso, adiposidade e ingestão alimentar que a prole de mães controle (CC-O). Além do mais, apresentou prejuízos na sinalização de insulina em tecidos periféricos como fígado, adiposo e músculo, e centrais, como o hipotálamo, provavelmente devido à maior ativação de vias inflamatórias. A reexposição à DH parece agir como um fator agravante para o desenvolvimento do fenótipo obeso, levando a resistência sistêmica à insulina e hiperleptinemia. É válido ressaltar que o tecido adiposo parece ser o tecido mais afetado na prole adulta após a reexposição da dieta (HH-O), o que pode contribuir para a desregulação metabólica observada. Em conjunto, nossos resultados sugerem que o consumo materno de dieta hiperlipídica durante a gestação e lactação pode ocasionar alterações no metabolismo glicídico da prole tanto em animais recém desmamados quanto adultos. Por fim, a obesidade materna leva à maior susceptibilidade ao desenvolvimento de obesidade e prejuízos na sinalização de insulina na prole que não podem ser revertidos pelo consumo de uma dieta controle, no entanto, podem ser agravados especialmente quando os animais são reexpostos à DH / Abstract: Modern lifestyle has resulted in an increase in the prevalence of obesity and its comorbidities in pregnancy and young population. Many effects from direct consumption of a high-fat diet (HFD) on glucose and lipid metabolism are well established. However, it is important to assess whether maternal consumption of HFD during critical periods of development can trigger epigenetic mechanisms, perpetuating changes in offspring metabolism and creating a vicious circle that cannot be broken. This study evaluated the potential effect of metabolic programming in impairing the insulin signaling in recently weaned offspring of obese dams. In addition, we investigated if early exposure to obesogenic environment is able to exacerbate the impairment of glucose metabolism in adult life in response to a high-fat diet. For this, Swiss female mice were fed with Stardard chow (SC) or HFD before and during mating, gestation and lactation. Tissues from male offspring were obtained at d28 and d82 to analyze activation of key proteins of inflammatory and insulin signaling pathways by Western Blot. Offspring of obese dams (HC-O) showed greater weight gain, adiposity and food intake than offspring of control dams (CC-O). Furthermore, they showed impairment in insulin signaling in central and peripheral tissues, associated to increased activation of inflammatory pathways. The HFD re-exposure seems to be an aggravating factor in development of obese phenotype leading to systemic insulin resistance and hyperleptinaemia. Moreover, adipose tissue was ultimately the most affected tissue in adult offspring after HFD rechallenged (HH-O) which may have contributed to the metabolic deregulation observed. Together our results suggest that maternal consumption of high-fat diet during pregnancy and lactation can cause changes in glucose metabolism of offspring in both weaned and adult animals. Additionally, maternal obesity leads to increase susceptibility to the development of obesity and impairment in insulin signaling in offspring that cannot be reversed by SC consumption, but can be aggravated especially when re-exposed to HFD / Mestrado / Metabolismo e Biologia Molecular / Mestra em Ciências da Nutrição e do Esporte e Metabolismo
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Evaluation of an Organic Mineral Complex on the Development of Cardiovascular Disease Risk Following a 10-week High-Fat Diet

January 2020 (has links)
abstract: According to the World Health Organization, obesity has nearly tripled since 1975 and forty-one million children under the age of 5 are overweight or obese (World Health Organization, 2018). Exercise is a potential intervention to prevent obesity-induced cardiovascular complications as exercise training has been shown to aid nitric oxide (NO) production as well as preserving endothelial function in obese mice (Silva et al., 2016). A soil-derived organic mineral compound (OMC) has been shown to lower blood sugar in diabetic mice (Deneau et al., 2011). Prior research has shown that, while OMC did not prevent high fat diet (HFD)-induced increases in body fat in male Sprague-Dawley rats, it was effective at preventing HFD-induced impaired vasodilation (M. S. Crawford et al., 2019). Six-weeks of HFD has been shown to impair vasodilation through oxidative-stress mediated scavenging of NO as well as upregulation of inflammatory pathways including inducible nitric oxide synthase (iNOS) and cyclooxygenase (Karen L. Sweazea et al., 2010). Therefore, the aim of the present study was to determine whether OMC alters protein expression of iNOS and endothelial NOS (eNOS) in the vasculature of rats fed a control or HFD with and without OMC supplementation. Six-week old male Sprague-Dawley rats were fed either a standard chow diet (CHOW) or a HFD composed of 60% kcal from fat for 10 weeks. The rats were administered OMC at doses of 0 mg/mL (control), 0.6 mg/mL, or 3.0 mg/mL added to their drinking water. Following euthanasia with sodium pentobarbital (200 mg/kg, i.p.), mesenteric arteries and the surrounding perivascular adipose tissue were isolated and prepared for Western Blot analyses. Mesenteric arteries from HFD rats had more uncoupled eNOS (p = 0.006) and iNOS protein expression (p = 0.027) than rats fed the control diet. OMC was not effective at preventing the uncoupling of eNOS or increase in iNOS induced by HFD. Perivascular adipose tissue (PVAT) showed no significant difference in iNOS protein expression between diet or OMC treatment groups. These findings suggest that OMC is not likely working through the iNOS or eNOS pathways to improve vasodilation in these rats, but rather, appears to be working through another mechanism. / Dissertation/Thesis / Masters Thesis Biology 2020
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The Effects of Adolescent High Fat Diet on Adult Prefrontal Cortex-Dependent Behavior, Stress Responsivity, and Microglial Reactivity,

Lloyd, Kelsey 29 September 2021 (has links)
No description available.
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Metabolické účinky chronického podávání metforminu u obézních myší v závislosti na složení vysokotukové diety / Metabolic effects of chronic metformin administration in obese mice depending on the composition of high-fat diet

Roubalová, Jana January 2011 (has links)
Obesity leads to many severe metabolic disorders, e.g. dyslipidemia, insulin resistance, ectopic fat accumulation in the liver and skeletal muscles, non-alcoholic fatty liver disease and finally diabetes mellitus type 2. Metformin (1,1-dimethylbiguanide) is the most favored medicament for the treatment and prevention of these disorders. It stimulates cellular glucose uptake and normalizes blood levels of lipid metabolites without triggering insulin secretion. Research on insulin resistance and diabetes is often realized through developing diet- induced obesity in laboratory animals. The aim of this project is to compare metabolic effects of two different high-fat diets named HFD and HSD. The HFD diet consists chiefly of n-6 polyunsaturated fatty acids (corn oil) and starch (100% glucose). The HSD diet contains mainly saturated fatty acids (lard) and sucrose (50% glucose and 50% fructose). I also studied metabolic effects of metformin by adding it continuously to the drinking water given to obese mice fed with the HFD or the HSD diet. Methods: Intraperitoneal glucose tolerance test (IPGTT), blood and tissue levels of lipid metabolites assessment, radio-immunological assessment of blood levels of insulin, assessment of AMPK activity in liver by western blotting. Results: Increased consumption of the...

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