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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.
1

Lipase-catalyzed acidolysis of algal oils with a medium-chain fatty acid, capric acid /

Hamam, Fayez, January 2003 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2003. / Bibliography: leaves 93-108. Also available online.
2

Processo simplificado de fabricação de margarinas com reduzidos teores de ácidos graxos saturados utilizando a tecnologia de estruturação de óleos / Simplified process for production of reduced saturated fatty acids margarines using oil structuring technology

Chaves, Kamila Ferreira, 1989- 07 July 2014 (has links)
Orientador: Daniel Barrera Arellano / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-25T11:28:26Z (GMT). No. of bitstreams: 1 Chaves_KamilaFerreira_M.pdf: 1834021 bytes, checksum: 17ab04d365f81e6b3faf3237da71b9f0 (MD5) Previous issue date: 2014 / Resumo: A redução do consumo de ácidos graxos saturados (AGS) na dieta, a fim de reduzir o risco de doenças cardiovasculares, tornou indispensável a busca por substitutos desse tipo de gordura, mediante novas alternativas tecnológicas, como a dos organogéis. O uso de estruturantes em sistemas lipídicos é visto como uma alternativa promissora, pois altera as propriedades físicas de óleos vegetais, sem que ocorram modificações químicas e aumento do teor de AGS, abrindo novas possibilidades para a produção de margarinas e spreads low sat e livres de ácidos graxos trans. O objetivo desse trabalho foi produzir margarinas utilizando a tecnologia de estruturação de óleos para reduzir a quantidade de AGS em comparação às margarinas comerciais convencionais. As matérias-primas, óleo de girassol alto oleico (OGAO), óleo de soja (OS), gordura interesterificada (GI), cera de candelilla (CC) e monoacilgliceróis (M), foram caracterizadas quanto a composição, qualidade e propriedades térmicas. O processo de elaboração das margarinas teste foi realizado em escala de bancada (1 kg), a fase lipídica foi fundida a 80ºC e misturada com a fase aquosa a uma temperatura de 60ºC, sob agitação de 300 rpm. O resfriamento até 30ºC ocorreu sob agitação a 37 rpm em uma sorveteira elétrica com parede de isolamento duplo, previamente resfriada em estufa B.O.D. a 5ºC. As margarinas comerciais avaliadas apresentaram composição de AGS entre 20,52 e 23,93% e teores de lipídios de 70 a 82%. A redução do teor de AGS foi calculada considerando a diferença da quantidade de AGS das margarinas teste em comparação com a média das margarinas comerciais. Foi possível notar através do planejamento experimental que quanto menores os teores de GI, CC e M nas formulações, maior a redução de AGS. As margarinas teste apresentaram melhor estabilidade da emulsão para as temperaturas avaliadas em comparação com as margarinas comerciais. Ocorreu maior exsudação de óleo nas margarinas comerciais em comparação às margarinas desenvolvidas conforme o planejamento experimental na temperatura de 35ºC por 48 horas. As margarinas testadas com OGAO e OS apresentaram menor valor na luminosidade (*L) em comparação às margarinas comerciais. A consistência e a espalhabilidade das margarinas testadas foram significativamente iguais a pelo menos 2/3 das margarinas comerciais avaliadas e a dureza foi estatisticamente igual para todas as margarinas testadas quando comparadas com as margarinas comerciais. Conclui-se que é possível produzir margarinas, mediante a tecnologia de estruturação de óleos, utilizando CC, M e GI como estruturantes, com redução do teor de AGS de 17,3 a 36,6% para as margarinas produzidas com OS e OGAO, respectivamente, em comparação com margarinas comerciais / Abstract: Reduce the consumption of saturated fatty acids (SFA) in the diet in order to reduce the risk of cardiovascular diseases, has made indispensable the search for substitutes for this kind of fat, through new technological alternatives, such as organogels. The use of structuring agents in lipid systems has been presented as a promising alternative, once that they change physical properties without any chemical modification or increase on the amount of SFA, which open new possibilities to the production of low sat and trans free margarines and spreads. The aim of this study was to produce margarines using oil structuring technology in order to reduce the amount of SFA compared to commercial margarines. Raw materials such as high oleic sunflower oil (HOSO), soybean oil (SO), interesterified fat (IF), candelilla wax (CW) and monoacylglycerols (M), were characterized due to their quality parameters, chemical composition and thermal properties. The processing of margarines were conducted in workbench scale (1kg per batch), the oil phase was melted, heating up to 80°C, and then mixed with an aqueous phase at 60°C, under controlled speed at 300 RPM. Cooling up to 30°C occurred under shear at 37 rpm using an electrical ice cream machine with a double wall isolated cube, previously cooled to 5°C. Commercial margarines with a SFA content between 20.52 and 23.93% and 70 to 82% amount of lipids were used as comparative standars. The reduction of SFA was calculated considering the amount of SFA on trial margarines and commercial comparative standards. It was possible to notice, through an experimental design, that smaller amounts of IF, CW and M on the formulations, resulted on reduction of SFA. Trial margarines presented better emulsion stability that commercial products. A higher oil exudation occurred for commercial margarines compared to the trial samples at 35°C for 48 hours. Tested margarines using HOSO and SO presents lower luminosity values (*L) when compared to commercial ones. Consistency and spreadability of trial margarines were statistically equal to, at least, 2/3 of the commercial margarines evaluated and hardness presented no statistical difference among all trial margarines when compared to commercial margarines. In conclusion, margarines produced by oil structuring technology using CW, M and IF as structuring agents, reduced the amount of SFA from 17.3 up to 36.6% in trial margarines with SO and HOSO, respectively when compared to commercial margarines / Mestrado / Tecnologia de Alimentos / Mestra em Tecnologia de Alimentos
3

The effect of saturated and unsaturated fatty acids on HEPG2 cells and the trehalose protection of HEPG2 cells on palmitate induced toxicity

Wu, Yifei. January 2008 (has links)
Thesis (M.S.)--Michigan State University. Dept. of Chemical Engineering and Material Science, 2008. / Title from PDF t.p. (viewed on July 29, 2009) Includes bibliographical references (p. 34-41). Also issued in print.
4

The Role of High Saturated Fatty Acid Diets on Skeletal Muscle Metabolism and Inflammation

Haynie, Kimberly Rebekah 22 December 2011 (has links)
The purpose of this study was to examine the relationship between metabolic adaptive response to 5 days of high SFA feeding, independent of positive energy balance, and diet-induced agonism of pro-inflammatory pathways. A secondary aim was to determine if the metabolic adaptive response in skeletal muscle to a single, high fat meal was altered by 5 days of high saturated fat feeding. Twelve college-age, non-obese males were studied and skeletal muscle samples were obtained prior to and concluding the consumption of a high SFA diet. In a subset of volunteers (N=6), we fed participants a high fat meal after the initial skeletal muscle biopsy and measured changes in postprandial endotoxin concentrations for four hours following the meal challenge. A second biopsy was obtained four hours after the meal challenge. Skeletal muscle samples were used to measure fatty acid oxidation, glucose oxidation, oxidative enzyme activities, mRNA expression of metabolic targets, and phosphorylation and total content of inflammatory proteins. In response to five days of high SFA feeding, skeletal muscle glucose and complete palmitate oxidation were significantly reduced as was the ratio of complete to incomplete fatty acid oxidation. Five days of high SFA feeding also attenuated the meal challenge-induced up-regulation of oxidative genes while augmenting postprandial increases in plasma endotoxin concentrations. To assess the relationship between metabolic adaptability and diet-induced inflammatory response we categorized volunteers by the diet induced percent change in fatty acid oxidation. Volunteers who were the least capable to adapt to high SFA feeding displayed the most robust increases in phosphorylation of inflammatory proteins. Lastly, we measured the correlation between the meal challenge associated percent change in oxidative and inflammatory markers in samples obtained prior to and following five days of high SFA feeding. We observed positive associations between the percent change in oxidative and inflammatory markers in samples obtained prior to the high SFA diet that were not observed following five days of high SFA feeding. These findings suggest that diet induced inflammatory response is involved in the regulation of adaptive response to high SFA feeding and that this relationship becomes dysregulated with chronic high SFA intake. / Ph. D.
5

Efeitos de suplementaÃÃo oral com mistura de Ãleos Ãmega 3; 6 e 9, com elevada relaÃÃo Ãmega 9/Ãmega 6 e baixa relaÃÃo Ãmega 6/Ãmega 3, sobre as adipocinas plasmÃticas em camundongos com Diabetes Mellitus / Effects of oral supplementation with omega oil blend 3, 6 and 9, with a high ratio 9/Ãmega omega 6 and low omega relationship 6/Ãmega 3 on plasma adipokines in mice with Diabetes Mellitus

Rosana Quezado 13 November 2012 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / O diabetes mellitus tipo 2 (DM2), doenÃa multifatorial, heterogÃnica, resulta de suscetibilidade genÃtica associada a fatores ambientais, especialmente sedentarismo e dieta rica em gorduras saturadas, e a obesidade. Caracteriza-se por resistÃncia à insulina (RI) e pela diminuiÃÃo da secreÃÃo desse hormÃnio. InflamaÃÃo moderada e crÃnica no tecido adiposo branco disfuncional, denominada âmeta-inflamaÃÃoâ, parece ser o elo entre obesidade, RI e DM2. Papel de adipocinas produzidas pelo tecido adiposo nessas afecÃÃes vem sendo investigado. Objetiva-se neste estudo verificar se suplementaÃÃo oral (SO) de mistura de Ãleos (MXO) com relaÃÃo de Ãmega 9 / Ãmega 6 (ω9/ω6) elevada e de Ãmega 6 / Ãmega 3 (ω6/ω3) baixa, de diferentes fontes de ω3, interfere em adipocinas plasmÃticas de camundongos com DM2. Depois de alimentados ad libitum com dieta da AIN-93G atà ficarem adultos, camundongos Swiss (CSW) machos receberam, por onze semanas, dieta AIN-93HA, hiperlipÃdica adaptada, para induÃÃo de DM2, confirmado em 90% deles. Mantida a dieta AIN-93HA, os CSW com DM2 receberam, em grupos, por sete dias, SO com MXO: GA: H₂O (controle nulo); GB: MXO [ω9:ω3 0,4:1;ω6:ω3 8:1 (controle neutro)]; GC: MXO [ω9:ω3 3,7:1; ω6:ω3-ALA 1,4:1]; GD: MXO [ω9:ω3 3,7:1;ω6:ω3-EPA+DHA de peixe 1,4:1]; GE: MXO [ω9:ω3 3,7:1; ω6:ω3-DHA de algas 1,4:1]. Por imunoensaios, realizou-se dosagem plasmÃtica de insulina e de adipocinas, fator de necrose tumoralâalfa (TNF-α); interleucina-6 (IL-6); interleucina-1 beta (IL-1β); fator ativador de monÃcitos (MCP-1); resistina (RES); leptina (LEP); inibidor do fator ativador de plasminogÃnio 1 (PAI-1) e adiponectina (AdipoQ). Constatou-se diferenÃa estatÃstica significante de adipocinas do grupo GE (ω3-DHA de algas), em relaÃÃo aos outros grupos, com aumento de IL-6 em relaÃÃo ao GC e GD; diminuiÃÃo de LEP em relaÃÃo ao GA; aumento de TNF-α em relaÃÃo aos grupos GB, GC e GD; e diminuiÃÃo de AdipoQ em relaÃÃo ao GB; assim como de RES entre os grupos GC (ω3-ALA) e GD (ω3-EPA+DHA). NÃo houve diferenÃa estatÃstica significante em nenhuma das variÃveis entre grupos controles. Continuidade de dieta rica em gordura saturada pode ter comprometido a eficÃcia da suplementaÃÃo de MXO ricos em ω3 e ω9. O âestado da arteâ demanda outros estudos para esclarecer o papel do DHA na âmeta-inflamaÃÃoâ. / Diabetes mellitus type 2 (DM2), a multifactorial disease, heterogenic results of associated genetic susceptibility to environmental factors, especially sedentary lifestyle and a diet rich in saturated fats, and obesity. It is characterized by insulin resistance (IR) and by decreasing the secretion of this hormone. Moderate and chronic inflammation in white adipose tissue dysfunctional, called "meta-inflammation," seems to be the link between obesity, IR and DM2. Role of adipokines produced by adipose tissue in these diseases has been investigated. Objective of this study was to verify whether oral supplementation (SO) of oil blend (MXO) compared with omega 9 / omega 6 (ω9/ω6) and high omega 6 / omega 3 (ω6/ω3) low, from different sources of ω3 interferes with adipokines plasma of mice with T2DM. After fed ad libitum with AIN-93G diet until they become adult Swiss mice (CSW) males received by eleven weeks AIN-93HA, hyperlipidic adapted to induce DM2 confirmed in 90% of them. Maintained the AIN-93HA, the CSW with T2DM were in groups of seven days, with MXO SO: GA: H ₂ O (null control) GB: MXO [ω9: ω3 0.4:1; ω6: ω3 8: 1 (neutral control)]; GC: MXO [ω9: 3.7:1 ω3, ω6: ω3-ALA 1.4:1]; GD: MXO [ω9: 3.7:1 ω3, ω6: ω3-EPA + DHA from fish 1.4:1]; GE: MXO [ω9: ω3 3.7:1; ω6: ω3, DHA from algae 1.4:1]. Why immunoassays, held measurement of plasma insulin and adipokines, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-1 beta (IL-1β), monocyte activating factor ( MCP-1), resistin (RES), leptin (LEP), an inhibitor of plasminogen activator 1 (PAI-1) and adiponectin (ADIPOQ). It found a statistically significant difference of adipokines group GE (ω3-DHA from algae), compared to the other groups, with increased IL-6 compared to GC and GD, fewer LEP compared to GA; increase of TNF- α in relation to groups GB, GC and GD, and ADIPOQ decrease compared to GB, as well as RES between GC (ω3-ALA) and GD (ω3-EPA + DHA). There was no statistically significant difference in any of the variables between control groups. Continuity diet high in saturated fat may have compromised the effectiveness of supplementation MXO rich in ω3 and ω9. The "state of the art" demand further studies to clarify the role of DHA in the "meta-inflamaÃÃoDM2, Adipokines, saturated fatty acids, omega fatty acids 3, 6 and 9 and" meta-inflammation
6

A molecular genetic approach to reducing the saturated fatty acid content of canola oil

Bondaruk, Mandy, University of Lethbridge. Faculty of Arts and Science January 2003 (has links)
Brassica napus is known to contain an endogenous and soluble stearoyl-acyl carrier protein (^918:0-ACP) desaturase, but does not express a palmitic (16:0)-ACP desaturase. Levels of 16:0 are low in canola oil and are associated with enhanced cholesterol biosynthesis in humans. In an attempt to further reduce the saturated fatty acid (SFA) content of canola oil, B. Napus L. cv Westar was transformed with a cDNA encoding a ^916:0-ACP desaturase from cat's claw (Doxantha unguis-cati L.). Arabidopsis thaliana was also transformed with this cDNA. Transformation of both oilseeds resulted in increased production of palmitoleic acid (^16:1) and many other effects of fatty acid composition. Overall, the SFA content did not decrease in either oilseed and investigation to why this effect occurred was examined using transgenic B. napus. Molecular genetic testing on second generation B. napus also determined the plants contained the cDNA of interest and were transcribing the cDNA. / xxi, 155 leaves : ill. ; 29 cm.
7

Implementation of Standard and Modified Soy Oils as Substitutes for Fish Oil in Feeds for Nile Tilapia

Mulligan, Bonnie Lynn 01 May 2013 (has links)
Seafood is the number one source of essential fatty acids, particularly, long-chain polyunsaturated fatty acids (LC-PUFA) in the human diet. As global population growth eventually surpasses what the world's wild commercial stocks can provide, reliance on the aquaculture industry to expand production will continue to increase in order to meet the demands of consumers worldwide. Currently, fluctuations in supply and cost coupled with environmental sustainability and contaminant concerns have motivated the aquaculture industry to research alternative lipid sources and feeding strategies in order to reduce the reliance on marine-derived resources. For most cultured species, replacing fish oil with terrestrial plant-based lipid sources is a minor dietary modification that has little consequence on production performance. However, fish raised on these plant-based lipid alternatives contain considerably higher medium chain polyunsaturated fatty acids (MC-PUFA) and n-6 fatty acids and less beneficial LC-PUFA and n-3 fatty acids within the fillets, thus negatively impacting the nutritional value of cultured seafood to the consumer. In order to alleviate this problem, producers can employ finishing strategies to restore fillet LC-PUFA content prior to harvest. As a complement to this approach, provision of dietary saturated fatty acids (SFA) and/or monounsaturated fatty acids (MUFA) in lieu of MC-PUFA appears to maximize the retention of LC-PUFA deposition during the grow-out period and may increase deposition during finishing. Accordingly, my objectives were to 1) assess whether the SFA, MUFA, and MC-PUFA content of the alternative lipid affected LC-PUFA levels in Nile Tilapia fed reduced fish oil feeds; and 2) using the optimal alternative lipid identified in the first objective, assess increasing fish oil replacement rates in conjunction with finishing to maximize product nutritional value and minimize fish oil usage in Nile Tilapia culture. To address the first objective, I assessed production performance and tissue composition of Nile Tilapia fed diets containing fish oil or blends of fish oil and various soybean-derived alternative lipids. Quadruplicate tanks of juvenile Nile Tilapia were fed diets containing fish oil (FISH, high in LC-PUFA) or a 50:50 blend of fish oil and standard (STD-SO, high in MC-PUFA), saturated fatty acid-enriched (SFA-SO, high in SFA), low α-linolenic (LO-ALA-SO, high in MC-PUFA), or hydrogenated (HYD-SO, high in MUFA) soybean oil for 16 weeks. Partial replacement of fish oil with soybean oils did not significantly affect production performance with the exception of the HYD-SO diet which yielded significantly reduced growth efficiency in comparison with some of the experimental diets, though not the FISH control. Despite distinctly different dietary fatty acid profiles, fillet fatty acid composition was similar among fish fed the FISH, SFA-SO, and HYD-SO diets. However, feeding the STD-SO and LO-ALA-SO diets resulted in significant enrichment of less desirable MC-PUFA and n-6 fatty acids within the fillet. Fillet LC-PUFA levels were equivalent among all groups despite the 50% reduction in dietary LC-PUFA intake among fish fed the soybean oil-based feeds. Based on these results, incorporation of STD-SO, SFA-SO, or LO-ALA-SO could be used as partial replacements for fish oil in Nile Tilapia feeds without impairing production performance, though SFA-rich soybean oils appeared to be the best alternative for maintaining a more "fish oil"-associated fillet fatty acid profile. Accordingly, the SFA-enriched soybean oil was selected for further study in the second objective trial that evaluated the effects of graded levels of fish oil replacement without or without implementation of finishing periods on production performance and fillet fatty acid composition. Nile Tilapia were fed feeds containing 100% fish oil (100-FO), the previously assessed SFA-enriched soybean oil (100-SFA-SO), or blends of fish oil and SFA-enriched soybean oil (50-SFA-SO, 75-SFA-SO). Triplicate groups of fish were fed the aforementioned diets exclusively throughout the feeding trial (100-SFA-SO unfinished, 75-SFA-SO unfinished, 50-SFA-SO unfinished) or in conjunction with 4 or 8 weeks of finishing with the 100-FO feed (100-SFA-SO + 4 wks, 100-SFA-SO + 8 wks, 75-SFA-SO + 4 wks, 75-SFA-SO + 8 wks, 50-SFA-SO + 4 wks, 50-SFA-SO + 8 wks) for a total of 20 weeks. Production performance was unaffected by dietary inclusion of SFA-enriched soybean oil when fed exclusively or in combination with fish oil, though growth performance was lower than observed in the previous trial and likely confounded by behavioral interactions and frequent spawning. After 12 weeks of consuming the SFA-enriched soybean oil grow-out diets, fillet levels of n-3 LC-PUFA were not statistically different from 100-FO control levels despite different levels of dietary inclusion. However, the high dietary levels of SFA in the experimental feeds did not translate into increased fillet SFA content, suggesting selective retention of LC-PUFA at the expense of fillet SFA. Finishing for 4 or 8 weeks increased fillet n-3 LC-PUFA content in all groups, though it appears that the 50- and 75-SFA-SO diets were more successful in maintaining acceptable health promoting n-3:n-6 ratios. Based on these results, SFA-enriched soybean oil-based feeds can be used as a cost-saving measure during grow-out, and the effects of these feeds on fillet fatty acid profile can be reversed to a considerable extent in as little as 4 weeks by implementing a finishing period prior to harvest. This approach is a promising strategy for minimizing fish oil usage while maximizing product value of cultured Nile Tilapia.
8

The Role of Fatty Acids on Toll-like Receptor 4 Regulation of Substrate Metabolism with Obesity

McMillan, Ryan P. 04 August 2009 (has links)
Growing evidence suggests that obesity and associated metabolic dysregulation occurs in concert with chronic low-grade inflammation. Toll-like receptors (TLR) are transmembrane receptors that play an important role in innate immunity and the induction of inflammatory responses. Our laboratory has observed that TLR4 expression is elevated in the skeletal muscle of obese humans and is associated with reduced fatty acid (FA) oxidation and increased lipid synthesis. Additionally, activation of this pathway by lipopolysaccharide (LPS), ex vivo, results in a shift in substrate metabolism favoring glucose as an energy substrate and preferential storage of FA in intracellular lipid depots. The purpose of this study was to examine the effects of saturated vs. monounsaturated FA on TLR4 transcription and signaling using ex vivo and in vivo models. C2C12 myotubes were incubated in FA-enriched growth medium with varying ratios of palmitate and oleate for 12 hours. Following FA treatment, cells were either collected for measures of mRNA and protein levels of TLR4 or challenged with LPS (500 ng/mL) for 2 hours to assess TLR4 mediated changes in interleukin-6 (IL-6) and glucose and fatty acid metabolism. TLR4 mRNA and protein content were increased in stepwise fashion with higher palmitate concentration (p<0.05). This was associated with an exacerbated LPS effect on IL-6 mRNA and protein levels, and glucose and fatty acid metabolism. To determine if these effects are translated to an in-vivo model, C57BL/6 mice were fed high saturated fat (HSF), high monounsaturated fat (HMF), and control diets for 10 weeks. Following the dietary intervention, animals were challenged with I.P. injections of either saline or LPS (~25μg/mouse), sacrificed 4 hours post-injection, and red and white gastrocnemius muscle were harvested for measures of expression and protein levels of TLR4 and IL-6, and glucose and fatty acid metabolism. TLR4 mRNA and protein levels were not altered with either the HSF or HMF diets. However, there was a heightened LPS response with regards to increases in IL-6 and TNF-α, and enhanced shifts in substrate metabolism following the HSF diet (p<0.05). These effects were not observed in response to the HMF diet. In conclusion, these data demonstrate that a milieu of high saturated fatty acids results in elevated sensitization of the TLR4 pathway in skeletal muscle. These results provide insight into how a westernized diet, one enriched in saturated fat, may link chronic inflammation with obesity-associated metabolic abnormalities. / Ph. D.
9

Efeito do consumo isocalórico da ração hiperlipídica e da administração da erva-mate (Ilex paraguariensis) sobre a expressão de proteínas envolvidas na via de sinalização da insulina no músculo sóleo de ratos Wistar / Effect of isocaloric high-fat diet consumption and the yerba mate (Ilex paraguariensis) administration on expression of proteins envolved in the insulin signaling pathway in soleus muscle of Wistar rats.

Tatiane Mieko de Meneses Fujii 14 May 2013 (has links)
Introdução: A ingestão de lipídios saturados está relacionada ao aumento da adiposidade, seja em humanos ou em modelos animais. O excesso de gordura corporal promove quadro de inflamação crônica e de baixa intensidade, condição esta associada à alteração no metabolismo da glicose, à resistência a ação da insulina e ao desenvolvimento de doenças crônicas não transmissíveis (DCNT). No tecido muscular, o aumento da atividade das proteínas quinases designadas quinase do inibidor do fator nuclear B (IKK)- e a c-Jun N-terminal quinase (JNK) contribui para o quadro de hiperglicemia por meio da redução da ativação do substrato 1 do receptor de insulina (IRS-1) e da proteína quinase B (Akt/PKB). A administração da erva-mate (EM), que possui compostos bioativos (CBA) com atividade anti-inflamatória, pode atuar na redução do processo inflamatório induzido pela elevada ingestão de ácidos graxos saturados. Objetivo: Investigar os efeitos do consumo isocalórico da ração hiperlipídica e da administração da erva-mate (Ilex paraguariensis) sobre a expressão de proteínas envolvidas na via de sinalização da insulina no músculo sóleo de ratos Wistar. Métodos: O delineamento experimental foi realizado em 2 momentos. Inicialmente, 36 ratos Wistar, machos foram distribuídos em dois grupos, os quais ingeriram ração controle (CON) (n= 18) ou hiperlipídica (HL) (n= 18), durante 12 semanas, caracterizando os grupos baseline CONBL e HLBL, respectivamente. Após esse período, 6 animais de cada grupo sofreram eutanásia, enquanto o restante dos animais de cada grupo foi distribuído em grupos que receberam, ou não, por gavagem, o extrato aquoso de erva-mate (EAEM) na dose de 1 g/kg de massa corporal, durante 4 semanas. Os animais foram submetidos ao teste oral de tolerância à glicose (oGTT) e ao teste intraperitoneal de tolerância à insulina (ipITT) na primeira, décima segunda e décima sexta semana do protocolo experimental. A partir do sangue, foram determinadas as concentrações de glicose, insulina, ácidos graxos não esterificados totais, adiponectina e proteína C reativa. A composição corporal foi avaliada por meio da carcaça dos animais. A partir do músculo sóleo, foi avaliada a expressão das proteínas JNK, IKK-, AKT e IRS1, nas suas formas totais e fosforiladas, e do fator de transcrição nuclear NFB, na sua forma fosforilada. Também foi realizada a avaliação histológica nesse tecido. Resultados: A ingestão isocalórica da ração HL não promoveu aumento de adiposidade, contudo, o grupo HLBL apresentou maior peso do coxim retroperitoneal em relação ao CONBL (p<0,05). O grupo HLBL mostrou hiperglicemia, resistência à ação da insulina, aumento das concentrações plasmáticas de colesterol total, colesterol não-HDL e de proteína C reativa em comparação ao grupo CONBL (p<0,05). No músculo sóleo, verificou-se aumento da razão fosfo:total IKK- no grupo HLBL em comparação ao CONBL (p=0,02). A administração do EAEM promoveu diminuição de 1 por cento (p<0,05) do ganho de peso corporal do grupo HL suplementado (HL+EM) em relação ao HL não suplementado, o qual apresentou 2 por cento de ganho de peso quando comparado ao HL+EM. Nos tempos de 5 e de 10 minutos após a carga insulínica, as glicemias dos animais HL+EM foram menores que as do grupo HL (p<0,05). Conclusão: A ingestão isocalórica da ração HL promoveu alterações metabólicas importantes, sugerindo possível ativação do processo inflamatório inclusive no tecido muscular. A administração da EM reduziu o ganho de peso, melhorou a sensibilidade à insulina e o perfil lipídico, contribuindo para a redução do risco cardiovascular / Introduction: The ingestion of saturated lipids is related to increase adiposity in humans or in animal models. The excess of fat improve the chronic and low grade of inflammation, condition associated with glucose metabolism disorders, insulin resistance and development of non-communicable diseases (NCD). In muscle tissue, the increase of proteins quinases activities, such as kinase inhibitor of B (IKK)- and c-Jun N terminal kinase (JNK) contributes for hyperglycemia thought the reduction of insulin receptor substrate (IRS)-1 and protein quinase B (AKT/PKB) activation. The administration of yerba mate (YM), which contain bioactive compounds with anti-inflammatory activity, can act on the reduction of inflammatory process induced by saturated fatty acid consumption. Objective: To investigate the effects of isocaloric high-fat diet consumption and Yerba mate (Ilex paraguariensis) administration on the expression of proteins involved in the insulin signaling pathway in Wistar rats soleus muscle. Methods: The experimental design was accomplished in 2 moments. Firstly, 36 Wistar rats, male, were distributed into two groups that ingested control (CON) (n=18) or high-fat (HF) (n=18) diets, during 12 weeks, characterizing baseline groups CONBL and HFBL, respectively. After this period, 6 animals from each group were euthanized, while the others were distributed in groups which received, or not, by oral gavage, yerba mate aqueous extract (YMAE) dose of 1 g/Kg of body weight), for 4 weeks. The rats were submitted to the oral glucose tolerance test (oGTT) and to the intraperitoneal insulin tolerance test (ipITT) on the first, twelfth and sixteenth week of experimental protocol. From the blood, were determined the concentrations of glucose, insulin, free fatty acids, adiponectin and C reactive protein. The body composition was available from the animal\'s carcass. From the soleus muscle, it was available the protein expression of JNK, IKK-, AKT and IRS-1, in total and phosphorylated forms and NF-B at the phosphorylated form. Also, it was realized the histology analysis in this tissue. Results: The ingestion of HF diet did not increase adiposity, however, the HFBL group presented retroperitoneal pad weight higher than CONBL (p<0,05). The HFBL group showed hyperglycemia, insulin resistance and elevated plasmatic concentrations of total cholesterol, HDL non-cholesterol and C reactive protein compared to CONBL group (p<0,05). On the soleus muscle, verified increase of phospho:total IKK- ratio in HFBL group in relation to CONBL (p=0,02). The supplementation with AEYM diminished 1 per cent (p<0,05) of weight gain in HL supplemented group in relation to HF not supplemented that presented 2 per cent of weight gain when compared to HF+YM. In times of 5 and 10 minutes after the insulin load, the glycemia of HF+YM were lesser than the HF group (p<0,05). Conclusion: The isocaloric high-fat diet intake promoted important metabolic changes, suggesting a possible activation of inflammatory process including in skeletal muscle. The administration of YM reduced the weight gain, improved the insulin sensibility and the lipid profile, contributing for the reduction of cardiovascular risk
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Efeito do consumo isocalórico da ração hiperlipídica e da administração da erva-mate (Ilex paraguariensis) sobre a expressão de proteínas envolvidas na via de sinalização da insulina no músculo sóleo de ratos Wistar / Effect of isocaloric high-fat diet consumption and the yerba mate (Ilex paraguariensis) administration on expression of proteins envolved in the insulin signaling pathway in soleus muscle of Wistar rats.

Fujii, Tatiane Mieko de Meneses 14 May 2013 (has links)
Introdução: A ingestão de lipídios saturados está relacionada ao aumento da adiposidade, seja em humanos ou em modelos animais. O excesso de gordura corporal promove quadro de inflamação crônica e de baixa intensidade, condição esta associada à alteração no metabolismo da glicose, à resistência a ação da insulina e ao desenvolvimento de doenças crônicas não transmissíveis (DCNT). No tecido muscular, o aumento da atividade das proteínas quinases designadas quinase do inibidor do fator nuclear B (IKK)- e a c-Jun N-terminal quinase (JNK) contribui para o quadro de hiperglicemia por meio da redução da ativação do substrato 1 do receptor de insulina (IRS-1) e da proteína quinase B (Akt/PKB). A administração da erva-mate (EM), que possui compostos bioativos (CBA) com atividade anti-inflamatória, pode atuar na redução do processo inflamatório induzido pela elevada ingestão de ácidos graxos saturados. Objetivo: Investigar os efeitos do consumo isocalórico da ração hiperlipídica e da administração da erva-mate (Ilex paraguariensis) sobre a expressão de proteínas envolvidas na via de sinalização da insulina no músculo sóleo de ratos Wistar. Métodos: O delineamento experimental foi realizado em 2 momentos. Inicialmente, 36 ratos Wistar, machos foram distribuídos em dois grupos, os quais ingeriram ração controle (CON) (n= 18) ou hiperlipídica (HL) (n= 18), durante 12 semanas, caracterizando os grupos baseline CONBL e HLBL, respectivamente. Após esse período, 6 animais de cada grupo sofreram eutanásia, enquanto o restante dos animais de cada grupo foi distribuído em grupos que receberam, ou não, por gavagem, o extrato aquoso de erva-mate (EAEM) na dose de 1 g/kg de massa corporal, durante 4 semanas. Os animais foram submetidos ao teste oral de tolerância à glicose (oGTT) e ao teste intraperitoneal de tolerância à insulina (ipITT) na primeira, décima segunda e décima sexta semana do protocolo experimental. A partir do sangue, foram determinadas as concentrações de glicose, insulina, ácidos graxos não esterificados totais, adiponectina e proteína C reativa. A composição corporal foi avaliada por meio da carcaça dos animais. A partir do músculo sóleo, foi avaliada a expressão das proteínas JNK, IKK-, AKT e IRS1, nas suas formas totais e fosforiladas, e do fator de transcrição nuclear NFB, na sua forma fosforilada. Também foi realizada a avaliação histológica nesse tecido. Resultados: A ingestão isocalórica da ração HL não promoveu aumento de adiposidade, contudo, o grupo HLBL apresentou maior peso do coxim retroperitoneal em relação ao CONBL (p<0,05). O grupo HLBL mostrou hiperglicemia, resistência à ação da insulina, aumento das concentrações plasmáticas de colesterol total, colesterol não-HDL e de proteína C reativa em comparação ao grupo CONBL (p<0,05). No músculo sóleo, verificou-se aumento da razão fosfo:total IKK- no grupo HLBL em comparação ao CONBL (p=0,02). A administração do EAEM promoveu diminuição de 1 por cento (p<0,05) do ganho de peso corporal do grupo HL suplementado (HL+EM) em relação ao HL não suplementado, o qual apresentou 2 por cento de ganho de peso quando comparado ao HL+EM. Nos tempos de 5 e de 10 minutos após a carga insulínica, as glicemias dos animais HL+EM foram menores que as do grupo HL (p<0,05). Conclusão: A ingestão isocalórica da ração HL promoveu alterações metabólicas importantes, sugerindo possível ativação do processo inflamatório inclusive no tecido muscular. A administração da EM reduziu o ganho de peso, melhorou a sensibilidade à insulina e o perfil lipídico, contribuindo para a redução do risco cardiovascular / Introduction: The ingestion of saturated lipids is related to increase adiposity in humans or in animal models. The excess of fat improve the chronic and low grade of inflammation, condition associated with glucose metabolism disorders, insulin resistance and development of non-communicable diseases (NCD). In muscle tissue, the increase of proteins quinases activities, such as kinase inhibitor of B (IKK)- and c-Jun N terminal kinase (JNK) contributes for hyperglycemia thought the reduction of insulin receptor substrate (IRS)-1 and protein quinase B (AKT/PKB) activation. The administration of yerba mate (YM), which contain bioactive compounds with anti-inflammatory activity, can act on the reduction of inflammatory process induced by saturated fatty acid consumption. Objective: To investigate the effects of isocaloric high-fat diet consumption and Yerba mate (Ilex paraguariensis) administration on the expression of proteins involved in the insulin signaling pathway in Wistar rats soleus muscle. Methods: The experimental design was accomplished in 2 moments. Firstly, 36 Wistar rats, male, were distributed into two groups that ingested control (CON) (n=18) or high-fat (HF) (n=18) diets, during 12 weeks, characterizing baseline groups CONBL and HFBL, respectively. After this period, 6 animals from each group were euthanized, while the others were distributed in groups which received, or not, by oral gavage, yerba mate aqueous extract (YMAE) dose of 1 g/Kg of body weight), for 4 weeks. The rats were submitted to the oral glucose tolerance test (oGTT) and to the intraperitoneal insulin tolerance test (ipITT) on the first, twelfth and sixteenth week of experimental protocol. From the blood, were determined the concentrations of glucose, insulin, free fatty acids, adiponectin and C reactive protein. The body composition was available from the animal\'s carcass. From the soleus muscle, it was available the protein expression of JNK, IKK-, AKT and IRS-1, in total and phosphorylated forms and NF-B at the phosphorylated form. Also, it was realized the histology analysis in this tissue. Results: The ingestion of HF diet did not increase adiposity, however, the HFBL group presented retroperitoneal pad weight higher than CONBL (p<0,05). The HFBL group showed hyperglycemia, insulin resistance and elevated plasmatic concentrations of total cholesterol, HDL non-cholesterol and C reactive protein compared to CONBL group (p<0,05). On the soleus muscle, verified increase of phospho:total IKK- ratio in HFBL group in relation to CONBL (p=0,02). The supplementation with AEYM diminished 1 per cent (p<0,05) of weight gain in HL supplemented group in relation to HF not supplemented that presented 2 per cent of weight gain when compared to HF+YM. In times of 5 and 10 minutes after the insulin load, the glycemia of HF+YM were lesser than the HF group (p<0,05). Conclusion: The isocaloric high-fat diet intake promoted important metabolic changes, suggesting a possible activation of inflammatory process including in skeletal muscle. The administration of YM reduced the weight gain, improved the insulin sensibility and the lipid profile, contributing for the reduction of cardiovascular risk

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