Dissertations / Theses: 'Fatty Acids, Omega-6'

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Purwaha, Preeti. "Effect of Dietary Omega-3 and Omega-6 Polyunsaturated Fatty Acids on Alcoholic Liver Disease." Diss., North Dakota State University, 2012. https://hdl.handle.net/10365/26488.

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PUFAs have been shown to modulate ALD by several mechanisms, including free radical generation from hepatic lipid peroxidation. However, how they modulate lipid peroxidation and generation of bioactive metabolites in ALD is poorly understood and it is still not clear which PUFAs (?-3 or ?-6) are beneficial or detrimental in ALD. Thus, our objective was to study the effect of ?-3/?-6 PUFAs on lipid peroxidation and ethanol mediated steatosis and inflammation. Using standard liquid diet (LDC), LDC with fish oil (rich in ?-3) and safflower oil (rich in ?-6), we studied the generation of bioactive metabolites, such as eicosanoids and free radicals generated via lipid peroxidation. In addition, we determined the effect of PUFAs on several inflammatory and fibrotic factors, e.g. gene as well as protein expression, using western blot and RT-PCR, respectively. We also investigated the effect of PUFA diets on novel targets, such as hepatic membrane transporters with potential role in liver inflammation. Our results suggest that ?-3 diet prevented while ?-6 based diets promoted the development of fatty liver and inflammation. ?-3 PUFA reduced AA-peroxidation by lowering hepatic AA concentration and expression of peroxidation enzymes, COX-2 and 5-LOX, resulting in lower generation of pro-inflammatory AA-derived PGs (Series-2), HETEs and free radicals, along with increase in anti-inflammatory EPA and DHA-derived PGs (Series-3). ?-3 diet might also reduce liver inflammation by preventing activation of NF-?B and induction of TNF-?. Rats fed with ?-3 diet showed high protein expression of efflux transporters, MRP-2 and ABCA1, indicating elimination of peroxidation metabolites and triglycerides from the liver and decreased inflammation. In contrast, ?-6 diets led to increase in AA-peroxidation and generation of AA-derived pro-inflammatory metabolites. ?-6 based diets also promoted fatty liver and inflammation by activating NF-?B, inducing TNF-? and downregulation of efflux transporters, MRP-2 and ABCA1. This study not only provides new insights into the effects and possible mechanisms by which ?-3 and ?-6 PUFAs may alter hepatic steatosis and inflammation, but also put forward new targets of research, such as hepatic membrane transporters in relation to liver pathology in ALD.

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Novak, Elizabeth Marie. "Dietary omega-3 and omega-6 fatty acids and neonatal liver metabolism." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/36743.

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It is well-known that the n-3 fatty acids are important regulators of fat and glucose metabolism in adult liver; however, to date most research on the importance of n-3 fatty acids in early development has focused on the brain, with little consideration of effects on other organs. This research addressed the importance of the essential n-3 and n-6 fatty acids for the liver during early development. A series of studies were conducted to address the impact of the amount, balance, and types of n-6 and n-3 fatty acids in the maternal diet and infant milk diet on lipids, protein abundance, gene expression, and relevant metabolites in the developing liver. Using milk-formula fed piglets, the first study demonstrated that the supply of n-6 and n-3 fatty acids impacts infant liver fatty acids, with high dietary n-6 fatty acids decreasing hepatic n-3 fatty acids in a pattern similar to n-3 fatty acid deficiency. Using the rat to address the impact of maternal fatty acid nutrition in gestation and lactation on the infant liver, the second study showed that adding n-3 fatty acids to the maternal diet lead to higher long chain n-3 fatty acids in neonatal liver, and this was associated with higher expression of enzymes of fatty acid oxidation and lower expression of enzymes of glycolysis and amino acid catabolism, with altered amino acid patterns when compared to n-3 fatty acid deficiency. In the third study, providing long chain n-3 fatty acids in the maternal diet led to marked increase in long chain n-3 fatty acids in milk and in the liver of the milk-fed rat pups, and this was associated with lower gene expression for enzymes of fatty acid synthesis and glycolysis and higher gene expression for an enzyme of ketogenesis in the neonatal liver. These studies provide new knowledge to show that the amount, types and balance of n-3 and n-6 fatty acids in the maternal and infant diet are relevant to hepatic metabolic regulation in the early postnatal period. Nutrition support of young infants should consider the needs and functions of n-3 fatty acids beyond the brain.

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Wang, Lei. "MODULATION OF ENDOTHELIAL CELL ACTIVATION BY OMEGA-6 AND OMEGA-3 FATTY ACIDS." UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_diss/573.

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Endothelial activation is considered to be an early and critical event in the pathology of atherogenesis which can be modified by environmental factors such as diet, pollutants, and lifestyle habits. Dietary andamp;ugrave;-6 and andamp;ugrave;-3 fatty acids have been reported to either amplify or diminish inflammatory responses related to atherosclerosis development. However, the interactions of andamp;ugrave;-6 and andamp;ugrave;-3 fatty acids with inflammatory cytokines or organic pollutants on endothelial cell activation are not well understood. The studies presented in this dissertation tested the hypothesis that andamp;ugrave;-6 and andamp;ugrave;-3 fatty acids alone, or in varying ratios can differently modulate pro-atherogenic mediators and inflammatory responses that are initiated by tumor necrosis factor- andamp;aacute; (TNF-andamp;aacute;) or polychlorinated biphenyls (PCBs) in endothelial cells. Exposure to TNF-andamp;aacute; induced oxidative stress, p38 MAPK, NF-andamp;ecirc;B, COX-2 and PGE2, which was amplified by pre-enrichment with linoleic acid but blocked or reduced by andamp;aacute;-linolenic acid. Furthermore, TNF-andamp;aacute;-induced caveolin-1 up-regulation and the co-localization of TNF receptor-1 with caveolin-1 was markedly increased in the presence of linoleic acid and diminished by andamp;aacute;-linolenic acid. Silencing of the caveolin-1 gene completely blocked TNF-andamp;aacute;-induced production of COX-2 and PGE2 and significantly reduced the amplified response of linoleic acid plus TNF-andamp;aacute;. These data suggest that omega-6 and omega-3 fatty acids can differentially modulate TNF-andamp;aacute;-induced inflammatory stimuli and that caveolae and its fatty acid composition play a regulatory role in these observed metabolic events. Besides cytokines, lipophilic environmental contaminants such as PCBs can also trigger inflammatory events in endothelial cells. Our data suggest that increasing the relative amount of andamp;aacute;-linolenic acid to linoleic acid can markedly decrease oxidative stress and NF-andamp;ecirc;B-responsive genes. The inhibitor study revealed that the modulation effect of andamp;ugrave;-6 and andamp;ugrave;-3 fatty acids on PCB toxicity was mainly through the oxidative stress sensitive transcription factor, NF-andamp;ecirc;B. In conclusion, our studies demonstrate that different dietary fats can selectively modulate vascular cytotoxicity caused by TNF-andamp;aacute; as well as by persistent organic pollutants such as PCBs. We also demonstrated the important relevance of substituting dietary andamp;ugrave;-3 fatty acids such as andamp;aacute;-linolenic acid for andamp;ugrave;-6 fatty acid such as linoleic acid in reducing cardiovascular diseases.

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Orchard, Tonya Sue. "Fatty Acids and Risk of Fracture in Postmenopausal Women." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306513275.

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Lewis, Amanda Gloria. "Treatment of Hypertriglyceridemia with Omega-3 Fatty Acids: A Systematic Review." Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd458.pdf.

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Ross, Trinette Noel. "Evaluation of bone biochemical markers and inflammatory markers in yearlings fed varying ratios of omega-6 and omega-3 polyunsaturated fatty acids." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1036.

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Franko, Bettina. "Use of Dietary Supplementation of Unsaturated Fatty Acids to Delay Onset of Learning and Memory Deficits in TgCRND8 Mice." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31933.

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Alzheimer’s disease (AD) is a complex neurodegenerative disorder, involving metabolic dysfunction, pathogenic aggregation of amyloid beta, and deteriorating cognitive function. Patients exhibit deficiency in omega-3,-6,-9 unsaturated fatty acids (UFAs) in plasma and brain membrane phospholipids, suggesting aberrant fatty acid metabolism influences pathology. Cognitive benefits of omega UFAs in AD remain unknown. Here, I examined effects of a four-month dietary supplementation with UFAs for capacity to alter learning and memory behaviour in an AD mouse model. Cognitive impairment in a fifth generation backcross (N5) C57BL/6Crl X C3H/HeJ TgCRND8 (Tg) mice was compared to control (NonTg) littermates, with respect to both males and females, at six months of age using the Morris Water Maze (MWM). Impairment differed between sexes; female Tg mice were severely impaired, whereas male Tg mice displayed delayed learning. A reduced visual acuity in Tg and NonTg mice, shown by adapted SLAG reflex test, did not impair spatial navigation in cued MWM. A four-month omega-6/-9 UFA oral treatment (75 mg/kg/day) improved learning and memory of Tg mice as compared to vehicle and untreated controls. Omega-3 UFAs, or vehicle alone, did not alter learning and memory of Tg and NonTg mice. Thus, dietary supplementation, particularly when enriched in omega-6/9 UFAs, can affect neural function, and delay conversion from a presymptomatic to symptomatic state in the TgCRND8 mouse model.

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Arnold, Andrew Richard. "Lipid oxidation in a model system and in meat." Thesis, University of St Andrews, 1989. http://hdl.handle.net/10023/14168.

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Lipid oxidation is the main factor which limits the shelf-life of meat when held under frozen storage. Research undertaken used pork phospholipid liposomes as a model for studying lipid oxidation in meat. Oxidation was followed by monitoring the decrease in the phospholipid unsaturated fatty acyl chains. It was found that the greater the level of unsaturation of the phospholipid fatty acyl chain the greater was their susceptibility to peroxidation. However, the results were not consistent and several reasons for the variation in rate are provided. At ambient temperatures copper (II) was found to be pro-oxidant in the peroxidation of liposomes. At temperatures below 0°C the prooxidant activity of copper (II) was significantly reduced. However copper again became highly pro-oxidant if sodium chloride was present. It is suggested that salt controls the copper ion concentration at sub-zero temperatures as the pro-oxidant activity of copper (II) is reduced on increasing the copper (II) concentration from 0.9 to 90 ppm. Other experiments found sodium nitrite and pholyphosphate to act as antioxidant and that liposome structure was an important factor in the rate of peroxidation. Four storage trials on pork burgers were undertaken to determine whether salt was also pro-oxidant in the stability of pork when held under frozen storage. The oxidative deterioration of the meat was followed by the following methods of analysis:- 1. The decrease in the unsaturated acyl chains of both total lipid and phospholipid. 2. The change in the colour parameters of the meat using reflectance spectroscopy. 3. The analysis of neutral lipid oxidation products by HPLC. 4. The organoleptic qualities of the pork using a trained panel of food assessors. The results from these storage trails showed that the deterioration of pork was minimised by storing the burgers at lower temperatures within the range 0 to -30°C. Salt was found to accelerate the oxidative deterioration of both uncooked and cooked pork when stored at -20°C. Nitrite was found to exhibit some antioxidant behaviour and reduce the pro-oxidant effect of salt.

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Galles, Deborah Pedroso. "Importância da relação dos ácidos graxos omega-6/omega-3 na alimentação." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-14052015-095032/.

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O experimento foi realizado no Biotério Experimental da USP em Pirassununga - SP. Na primeira fase foram utilizados 42 coelhos machos em crescimento da raça Nova Zelândia mantidos individualmente durante todo o experimento. O ensaio biológico totalizou 150 dias. Na Fase 1 os animais receberam dietas com indução de hipercolesterolemia (0,5% de colesterol), com desequilíbrio na proporção de Omega-6/Omega-3 (n-6:n-3) de 15:1 e vice versa e balanço na proporção de n-6:n-3 de 4:1 (controle), totalizando 6 ensaios, os quais foram divididos aleatoriamente em 7 grupos de 6 coelhos cada. Óleos de girassol e de peixe foram utilizados como fontes de ácidos graxos poli-insaturados n-6 e n-3, respectivamente. Na Fase 2, os animais remanescentes continuaram recebendo as mesmas dietas, exceto no grupo B (hipercolesterolemia) que passou a receber o tratamento controle para verificar o efeito. No final da Fase 1, três animais de cada grupo foram eutanasiados com retirada da artéria aorta para determinação de placas lipídicas, histopatológica, colesterol total e imunohistoquímica para verificação da expressão da enzima LDL-receptor e determinação histopatológica do tecido hepático. Em soro foram realizadas determinações de perfil de ácidos graxos, colesterol total, LDL e HDL-colesterol e triacilgliceróis. Células endoteliais aórticas de coelhos foram isoladas para a realização do teste dose resposta com óleo de peixe para identificar a melhor relação do consumo destes ácidos graxos comparando com o experimento in vivo. O objetivo deste trabalho foi monitorar os efeitos do fornecimento de cada dieta sobre o teor de colesterol total, LDLcolesterol, HDL-colesterol e triacilgliceróis em sangue de coelhos. No geral, o perfil de ácidos graxos no soro correspondeu diretamente com a dieta consumida. Os principais efeitos dos ácidos graxos poli-insaturados Omega 3 foi a redução dos lipídios séricos quando os coelhos remanescentes da dieta hipercolesterolêmica (0,5% de colesterol e n-6:n-3 de 2:1) passaram a receber o equilíbrio da relação de ácidos graxos 4:1 de n-6:n-3. O teor de colesterol total no soro, artérias e o crescimento dos ateromas foram influenciados pelo elevado consumo de ácidos graxos n-6 e n-3 associados à adição de colesterol nas dietas. Por outro lado verificamos que o excesso de Omega 3 associado ou não ao colesterol contribuiu para o agravamento das placas ateroscleróticas inclusive deposição de cálcio nas mesmas e paredes endoteliais. Provavelmente, o excesso de n-3 tenha ocasionado efeito contrário às suas funções anti-inflamatória, antiagregatória e anti-trombótica. Dietas hipercolesterolêmicas provocaram esteatose hepática e o elevado consumo de Omega-6 em detrimento do baixo consumo de Omega -3 induziram hepatite crônica. Já o consumo elevado de Omega-3, sem colesterol, regrediu a esteatose hepática nos animais. O consumo equilibrado de n-6:n-3 reduziu a expressão da enzima LDL-receptor no grupo que anteriormente recebeu dieta hipercolesterolêmica. Ressaltando-se a importância do consumo equilibrado destes ácidos graxos já que esta enzima é controlada pelo colesterol livre circulante. No teste dose-resposta em células endoteliais da aorta de coelhos foi evidenciado que a melhor proporção de n-6:n-3 seria de 9 vezes mais do que a concentração de Omega 3 recomendada de 5:1.
The experiment was conducted at the Experimental Biotery by USP in Pirassununga - SP. In the first phase were used 42 male rabbits growing New Zealand breed individually maintained throughout the experiment. The biological assay amounted to 150 days. In phase 1, the animals received diets induced hypercholesterolemia (0.5% cholesterol) with imbalance in the ratio of Omega-6 / Omega-3 (n-6 / n-3) 15:1 and vice versa, and balance the ratio of n-6 / n-3 of 4:1 (control), totaling six tests, which were randomly divided into 7 groups of six rabbits each. Sunflower and fish oils were used as sources of fatty acids polyunsaturated n-6 and n-3, respectively. In Phase 2, the remaining animals continued to receive the same diets except in group B (hypercholesterolemia) who went on to receive the control treatment to check the effect. At the end of Phase 1, three animals from each group were sacrificed with the aorta artery removed for determination of lipid plaques, histopathology, immunohistochemistry and total cholesterol to verify the expression of LDL-receptor enzyme and determination of histopathological liver tissue. In serum profile were made determinations of fatty acids, total cholesterol, LDL and HDL cholesterol and triglycerides. Aortic endothelial cells of rabbits were isolated to perform the dose response test with fish oil to identify the best value for the consumption of these fatty acids compared to the in vivo experiment. The objective of this work was to monitor the effects of provision for each diet on total cholesterol, LDL-cholesterol, HDLcholesterol and triglycerides in the blood of rabbits. In general, the profile of fatty acids in serum corresponded directly with the diet consumed. The main effects of polyunsaturated Omega 3 fatty acids was the reduction of serum lipids when the remaining rabbits with hypercholesterolemic diet (0.5% cholesterol and n-6: n-3 2:1) have received the balance of the relationship fatty acid 4:1 n-6: n-3. The total cholesterol content in serum, the growth of arteries and atheroma were influenced by a high intake of n-6 fatty acids and n-3 associated with the addition of cholesterol in diets. On the other hand we verified that the excess of Omega 3 with or without cholesterol contributed to the aggravation of the atherosclerotic plaques including deposition of calcium in them and endothelial walls. Probably the excess of n-3 has caused the opposite effect to their anti-inflammatory, anti-thrombotic and anti-aggregatory functions. Hypercholesterolemic diets caused hepatic steatosis and high intake of Omega-6 to the detriment of low consumption of Omega -3 induced chronic hepatitis. High consumption of Omega-3, no cholesterol, decreased hepatic steatosis in animals. Highlighting the importance of the balanced intake of this fatty acids, since this enzyme is controlled by circulating free cholesterol. In dose-response test in endothelial cells of the rabbits aorta was evident that the best ratio of n-6: n-3, nine times more than the recommended concentration of Omega 3 to 5:1.

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Lopes, Débora Cristina Nichelle. "Óleo de linhaça na dieta de frangos de corte." Universidade Federal de Pelotas, 2012. http://repositorio.ufpel.edu.br/handle/ri/2607.

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Made available in DSpace on 2014-08-20T14:38:47Z (GMT). No. of bitstreams: 1 tese_debora_cristina_nichelle_lopes.pdf: 1786515 bytes, checksum: d80cc96f59e6d05a91186e55422d1bfe (MD5) Previous issue date: 2012-03-22
A trial was conducted to evaluate the effects of replacing soybean oil by linseed oil on performance, carcass traits, physicochemical characteristics, sensory properties of meat and plasma biochemical profile of poultry. A total of 448 one day old male birds (Cobb 500) where randomly allotted to 4 treatments and 8 replications in a completely randomized assay for 35 days. The following treatments were tested: T1 = 100% soybean oil (SO) as the main dietary energy source; T2 = 50% SO and 50% linseed oil (LO); T3 = 25% SO and 75% LO; and T4 = 100% LO. Performance of birds was not affected (P>0.05) when LO replaced SO in the diets during the whole experimental period. Additionally, no significant difference (P>0.05) was observed in carcass traits of birds fed diets containing LO. Moreover, plasma biochemical profile was not affected (P>0.05) as the level of LO increased in the diets. Omega-3 fatty acids (n3-PUFA) increased in the meat, omega-6 fatty acids (n6-PUFA) and meat n6:n3 decreased as the dietary level of LO was increased. Reduction of drumstick fat was observed increasing levels of LO in the diet (P<0,05). No significant differences (P>0.05) were observed for dry matter, protein, fat and cholesterol in the meat. Also, no significant differences (P>0.05) were found for physicochemical characteristics and sensory properties of meat. Replacing SO by LO in the diet might be carried out with no effect on performance, carcass traits and biochemical profile of poultry. Dietary LO enriched poultry meat with C18:3n3, C20:3n3 e C20:5n3 and reduced n6:n3 ratio without any negative effects on chemical composition and physicochemical characteristics and sensory properties of meat.
O presente estudo foi realizado com o objetivo de avaliar os efeitos da substituição do óleo de soja pelo óleo de linhaça sobre o desempenho produtivo, características de carcaça, características químicas, instrumentais, sensoriais e perfil de ácidos graxos da carne além do perfil bioquímico sérico de frangos de corte. Utilizou-se 448 frangos da linhagem Cobb 500, machos, de um dia de idade, distribuídos em 4 tratamentos, com 8 repetições, em um delineamento completamente casualizado, por um período de 35 dias. Os tratamentos utilizados foram: T1 = 100% de óleo de soja (OS) como principal fonte energética; T2 = 50% de OS e 50% de óleo de linhaça (OL); T3 = 25% de OS e 75% de OL; e T4 = 100% de OL. A substituição do OS pelo OL na dieta não afetou (P>0,05) o desempenho produtivo dos frangos durante todo o período experimental. Também não foram observadas diferenças significativas (P>0,05) sobre as características de carcaça das aves que receberam OL na dieta. Da mesma forma, os níveis plasmáticos dos frangos não diferiram significativamente (P>0,05) com o aumento de óleo de linhaça na dieta. O aumento do OL na dieta promoveu o incremento de ácidos graxos da família ômega-3 (3n-AGPI), a redução de ácidos graxos da família ômega-6 (6n-AGPI) e da relação 6n-AGPI:3n-AGPI na carne. Houve redução no teor de gordura da sobrecoxa com o aumento de OL na dieta (P<0,05). Não foram observadas diferenças significativas (P>0,05) no percentual de matéria seca, proteína, gordura e colesterol na carne. Também não foram observadas diferenças significativas (P>0,05) sobre as características físicoquímicas e sensoriais da carne. A substituição do OS pelo OL na dieta de frangos de corte pode ser realizada sem afetar o desempenho produtivo, características de carcaça e perfil bioquímico. O OL na dieta de frangos de corte promoveu o enriquecimento da carne com C18:3n3, C20:3n3 e C20:5n3 e a redução na relação 6n- AGPI:3n-AGPI, sem afetar a composição química e as características físicoquímicas e sensoriais da carne.

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Nikravan, Ramin. "Antioxidant and omega-3 fatty acid intake in the modulation of respiratory illness & asthma in children." Thesis, Curtin University, 2011. http://hdl.handle.net/20.500.11937/689.

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Background and aim: Asthma is one of the major public health problems in Australia with prevalence in West Australian children reported up to 31%. The rise in asthma prevalence in Western societies may be related to changes in dietary habits, as diets are often low in antioxidant nutrients and omega-3 fatty acids (n-3) and high in omega-6 fatty acids (n-6).The association between antioxidants, fatty acids and asthma is however controversial and there is a need for further investigation to clarify the role of these nutrients on asthma.The aim of this study was to investigate the dietary exposures of n-3, n-6 and antioxidant nutrients proposed to have protective effects against asthma symptoms. Data gathered over fourteen years in a prospective pregnancy cohort study were analysed. We hypothesised that n-3 fatty acids and antioxidant nutrients (vitamins A, C, E, β-carotene antioxidants manganese and zinc) would be protective against asthma symptoms.Methods: The Western Australian Pregnancy Cohort (Raine) study is a longitudinal study following 2868 children from birth to 14 years of age. This project consisted of two analyses as part of the overall study. Study One was a cross-sectional analysis of 1531 children at age 14 identified as having current asthma (n=167) or no asthma (n=1364). Study Two was a longitudinal analysis from a subset of the overall study whereby children were identified as having current asthma or no asthma at eight (n=335) and 14 (n=242) years of age. Dietary information was collected from food frequency questionnaires (FFQ) in both studies and red blood cell fatty acid content was measured in children for Study One. Student’s t-tests and ANOVA allowed comparisons of food and nutrient intakes between children with asthma or no asthma for both studies. In Study One depending on the outcome of interest, multinominal or binary logistic regression was performed. In Study Two, food and nutrients that showed a significant difference between asthma groups in ANOVA analyses (p<0.05) were included in analysis of covariance (ANCOVA) to determine whether they made an independent contribution after adjustment for age, sex, BMI and total energy intake. The Bonferroni post hoc test was applied to control for false positive results.Results of Study One: The participants were 50.8% male (n=778) and 49.2% female (n=753). One hundred and sixty seven adolescents (10.9%) had asthma categorised as mild (4.0%), moderate (4.4%) or severe (2.5%). Two hundred and eighteen adolescents (14.2%) had current wheeze. The most common allergy outcome was atopy (44.5%) n= 682. The least common allergy outcome was eczema (10.7%).The large majority of dietary antioxidants and fatty acids tested were unrelated to asthma and asthmatic symptoms. However, after performing regression analysis and adjusting for potential confounders (BMI, age, gender and total daily energy intake) increased intake of vitamin C showed protective association with asthma (adjusted OR= 0.997, 95% CI= 0.994–0.999) and increased consumption of berry fruits showed protective effects on atopy (adjusted OR= 0.988, 95% CI= 0.976–0.999).Increased level of docosahexaenoic acid (22:6n3) in RBC membrane showed protective effects on BHR (adjusted OR= 0.814, 95% CI= 0.669–0.989). The adjusted ratio of n6:n3 showed detrimental association with asthma (OR= 1.072, 95% CI= 1.009–1.139) and wheezing episodes (OR= 1.064, 95% CI= 1.007–1.124).Results of Study Two: None of the antioxidant nutrients were shown to be associated with asthma. Unadjusted ANOVA analysis demonstrated a significant association between asthma diagnosis and arachidonic acid (20:4n6) (p=0.039). However, after performing ANCOVA and controlling for the confounders (age, sex, BMI and total energy) the association became non-significant (p=0.330). In crude analyses the n6:n3 ratio was higher for asthmatic adolescents at eight and 14 years (3.38) compared to those with no asthma (2.78) (p=0.013). This ratio remained significant after adjusting for the confounders (p=0.030)Conclusions: Study One and Two provide some evidence on protective effects of antioxidants and fruits on asthmatic symptoms in adolescents. We found that while controlling for potential confounders, increasing intake of vitamin C by 1 mg/day results in a 0.3% reduction in the risk of developing asthma. We demonstrated that for every 1 g/day increased intake of berry fruits there was 1.2% reduction in the risk of having atopy. We showed that by increasing 1 mmol/L in the level of docosahexaenoic acid in RBC membrane there was 18.6% reduction in the risk of having BHR. We also demonstrated that for every 1 unit increase in n6:n3 ratio, there was 6.4% increase in the risk of developing wheezing episodes and 7.2% increase in the risk of having asthma. Therefore, Our study suggests that the ratio of n6:n3 in diet may play a modulatory role in the expression of asthma, suggesting that promotion of increased total n-3 and reduced n-6 may protect against asthmatic traits in childhood and early adolescence.

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Howard, Alicia Dawn. "Indices of stress in exercising horses fed diets containing varying amounts of omega-6 and omega-3 polyunsaturated fatty acids." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2517.

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Dietary omega-3 polyunsaturated fatty acids have shown substantial benefits in humans including lowered serum cholesterol, blood pressure and indices of stress. The caloric and extracaloric benefits of feeding fat supplemented diets to performance horses are well documented (Webb et al., 1987; Meyers et al., 1989; Julen et al., 1995). However, omega-3 polyunsaturated fatty acids have not been studied to any great extent. This study was conducted to determine the efficacy of feeding omega-3 fatty acids on indices of stress and serum cholesterol in horses. Nine three- and four-year old horses were assigned to diet treatments according to sex, age and athletic ability. Concentrate diets consisted of: control (A), fatsupplemented diet with corn oil (B) and fat-supplemented diet with extruded/expelled soybean oil (C; N-3). Overall, heart rates were lower in horses fed the fat-supplemented diets compared to the control diet. On reining and cutting exercise days, heart rates were lower (P<.05) in horses fed fat-supplemented diets vs. the control diet. There were no differences (P>.05) in heart rates during exercise on reining and cutting days between horses fed the two fat-supplemented diets. Recovery heart rates following the SET from the end of exercise to 60 minutes recovery (R), were significantly quicker in horses fed diet C. Plasma cortisol concentrations were lowest in horses fed the soy oil-supplemented diet and highest in horses fed the corn oil-supplemented diet. Across treatments, plasma cortisol concentrations during the SET rose due to the onset of exercise and remained significantly higher (P<.05) than baseline during the SET. Serum cholesterol concentrations were higher in horses fed corn oil-supplemented diets than in the control or the soy oil-supplemented diets. There was no significant change (P>.05) in body weight between horses consuming these three diets. However, when compared to consuming diets B and C the horses fed diet A had higher (P<.05) concentrate intakes. There was no significant difference in hay intake (P>.05) between horses consuming the three diets.

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Rajendiran, Ethendhar. "The differential effects of omega-6 and omega-3 polyunsaturated fatty acids on intestinal microbial ecology and host redox responses." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43596.

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The gastrointestinal tract harbors complex bacteria which plays an important role in health and disease. Gut microbial antigens, in conjunction with ingested dietary components, are important in intestinal immune homeostasis. High omega-6 polyunsaturated fatty acid (n6 PUFA) can induce oxidative stress and inflammation in the gut. In contrast, omega-3 (n3 PUFAs) supplementation can cure several inflammatory diseases. However, the relationship between dietary PUFAs and the intestinal microbiota remain unknown. Our study was to determine the effect of high fat diets with varying n6 and n3 PUFA on mice microbiota and host responses. We used 20% wt/wt corn oil (high n6 PUFA), corn + fish oil (19% wt/wt corn oil added to 1% wt/wt fish oil; high n6 PUFA + long chain n3 PUFA), 20% wt/wt canola oil (low n6 PUFA) as diets keeping 5% wt/wt corn oil as a chow control. After feeding mice the high fat diets for 5 weeks, Quantitative Polymerase Chain Reaction (qPCR) was used to examine the gut microbiota.Immunofluorescence was carried out to examine immune and redox responses. All high fat diets,regardless of composition, significantly reduced Bacteroides spp. and increased in intestinal epithelial cell death. Mice fed 20% corn oil had high levels of bacteria from the Clostridium and Enterobacteriaceae; associated with inflammatory bowel disease (IBD). In contrast, mice fed corn oil diets supplemented with fish oil, had enriched beneficial microbe Lactobacillus and lower levels of Enterobacteriaceae and Clostridia species. Fish oil also reduced neutrophil infiltration as well suggesting that n3 PUFA is anti-inflammatory. In addition, unexpectedly, fish oil supplementation induced oxidative stress in the colon evident by the increased presence of 4-hydroxy-2-nonenal, a lipid peroxide product, and dual oxidase 2, which generates H₂O₂. In addition, catalase, an antioxidant was also low in the fish oil group. Canola oil, which contains n3, n6 PUFAs and a monounsaturated fat oleic acid, alters the microbiota similar to the corn oil group. Overall, our research suggests that n6 PUFA alters the microbial composition, enriching it with detrimental microbes. Fish oil supplementation can reverse this effect. However, we also provide evidence of fish oil supplementation increasing oxidative stress.

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Eljach, Mosquera Sara. "Purslane (Portulaca oleracea L.) an excellent source of omega-3 and omega-6 fatty acids with abatement of risk factors." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=123256.

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Wild plants are usually not consumed in daily diets, but represent a great source of nutrients for humans. Purslane, a plant known as a common weed, is known to have elevated concentration of fatty acids (ω-3 and ω-6), essential compounds for human health. The objective of this study was to determine how the nitrogen and photoperiod affected the concentration of fatty acids in purslane, as well as the concentration of oxalic acid (component with a slightly negative effect on human health). Nine accessions of purslane from Canada, Afghanistan, Saudi Arabia, Syria and Iran were studied in controlled environment growth chambers. Two ratios of nitrate:ammonium (50:50 and 25:75) fertilizers and two photoperiods (12 and 16 hours) were studied. Statistical analysis was performed using a factorial model with three levels. The leaves and stems of purslane plants that were grown under 12 hours photoperiod and 50:50 N03:NH4+ had the highest concentrations of linoleic acid and ⍺-linolenic acid, and the lowest concentration of oxalic acid. Among the accessions studied, an accession from Quebec epitomized the most viable selection for human consumption.
Les plantes sauvages, généralement non-consommés dans l'alimentation quotidienne, pourraient représenter une grande source d'éléments nutritifs pour les humains; le pourpier est une plante connue comme une mauvaise herbe, il est connu pour avoir une concentration élevée d'acides gras (α-3 and α -6), des composants essentiels pour la santé de l'Homme. L'objectif de cette étude était de déterminer comment l'azote et la photopériode affectent la concentration des acides gras du pourpier, ainsi que la concentration de l'acide oxalique (composant avec un effet légèrement négatif sur la santé de des humains). Neuf accessions de pourpier en provenance du Canada, d'Afghanistan, d'Arabie Saoudite, de Syrie et d'Iran ont été étudiées, des chambres de croissance ont été utilisées pour assurer un environnement de croissance maîtrisée. Deux ratios de nitrate d'ammonium: (50:50 et 25:75) ont été étudiés associés à deux photopériodes (12 et 16 heures). L'analyse statistique a été réalisée à l'aide d'un modèle factoriel à trois niveaux. Les résultats indiquent que les plantes cultivées en dessous de 12 heures de photopériode et 50:50 N03: NH4 + ont eu les plus grandes valeurs de concentration de l'acide linoléique et l'acide ⍺-linolénique et la plus faible concentration de l'acide oxalique, en terme de feuilles et de tiges de pourpier. Parmi toutes les accessions étudiées, l'accession du Québec représentait la culture la plus viable pour la consommation humaine.

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Vierheller, Pamela Diane. "Polyunsaturated Fatty Acids in the Human Diet: Implications for Cognition, Mood, and Neural Development." Cincinnati, Ohio University of Cincinnati, 2007. http://www.ohiolink.edu/etd/view.cgi?ucin1179332516.

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Thesis (M.A.)--University of Cincinnati, 2007.
Title from electronic thesis title page (viewed July 19, 2007). Includes abstract. Keywords: Polyunsaturated fatty acids; PUFA; omega-3; omega-6; cognition; mood; neural development Includes bibliographical references.

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Smolinski, Justin Bruce. "Dietary Chemoprevention Studies in Preclinical Models of Prostate Cancer: Bioactive Lipids and Vitamin D." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1282069758.

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Quezado, Rosana. "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." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=9149.

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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 Ã 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 atÃ 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

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Ghandour, Rayane. "Effet des acides gras polyinsaturés sur la conversion des adipocytes blancs en adipocytes brites." Thesis, Nice, 2016. http://www.theses.fr/2016NICE4010/document.

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Il existe deux populations d’adipocytes thermogéniques, les adipocytes bruns du tissu adipeux bruns et les adipocytes ‘’brites’’ qui apparaissent au sein du tissu adipeux blanc. Récemment, la caractérisation d’adipocytes bruns et brites fonctionnels chez l’homme adulte a permis d’envisager de nouvelles approches nutritionnelles et thérapeutiques pour traiter l’obésité. Mon projet de thèse a porté sur l’étude des effets des acides gras polyinsaturés ω6 et ω3 d’origine alimentaire sur la conversion des adipocytes blancs en brites, d’abord chez l’homme in vitro puis chez les rongeurs in vivo. Nous avons pu ainsi démontrer que l'acide arachidonique ω6 à l’origine de nombreux métabolites oxygénés, exerce 1) un effet inhibiteur sur la formation des adipocytes brites grâce aux prostaglandines E2 et F2α, et 2) un effet inducteur via la prostacycline. En effet, celle-ci active la conversion des adipocytes blancs en brites par une voie impliquant le récepteur membranaire IP et les récepteurs nucléaires PPARs. En nous basant sur les recommandations nutritionnelles actuelles chez l’Homme, qui ont pris en considération l’insuffisance de l’apport en acides garsω3 par rapport à l’excès des ω6, nous avons pu montrer chez la souris qu’une supplémentation en acides gras ω3 dans le régime alimentaire était capable d’inhiber l’effet néfaste des acides gras ω6 et d’activer le tissu adipeux brun. Nos résultats démontrent l’importance de la biodisponibilité de l’acide arachidonique dans la biologie du tissu adipeux et permettent de renforcer l’idée que le rééquilibrage du ratio ω6/ω3 est un outil de choix dans la prévention du surpoids et de l’obésité et les maladies métaboliques associées
There are two types of thermogenic adipocytes able to use fatty acids and glucose to produce heat. We distinguish brown adipocytes from the brown adipose tissue and ‘’brite’’ adipocytes which occur into the white adipose tissue. Recently, the characterization of functional brown and brite adipocytes in adult humans has led to the consideration of their use to treat obesity by increasing energy expenditure. My thesis project was to study the effect of dietary polyunsaturated fatty acids, on the conversion of white into brite adipocytes, in vitro and in vivo, in humans and rodents respectively. We demonstrated that arachidonic acid ω6, precursor of prostaglandins, has 1) an inhibitory effect on the recruitment of brite adipocytes via prostaglandins E2 and F2α and 2) an activatory effect via prostacyclin. In fact, prostacyclin induces the conversion of white into brite adipocytes through the IP receptor and the PPARs signaling pathways. Based on human present nutritional recommendations, we demonstrated that a supplementation of ω3 fatty acids in mice diet was able to inhibit the negative effect of ω6 fatty acids and activate brown adipose tissue. Our data highlights the importance of arachidonic acid bioavailability on the biology of adipose tissue and reinforce the idea that an equilibrate ω6/ω3 ratio is a tool that can be used to prevent overweight obesity and associated metabolic disorders

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Hughes, Jaime. "The effect of dietary omega-3 and -6 polyunsaturated fatty acids on ovine ovarian function and the pre-implantation embryo." Thesis, University of Nottingham, 2011. http://eprints.nottingham.ac.uk/11800/.

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There is considerable interest in the beneficial role of dietary polyunsaturated fatty acids (PUFA) on reproduction in ruminants. Detailed information regarding the mechanisms behind this beneficial effect is limited. The main objective of this thesis was to test the effects of dietary supplementation with omega-3 (n-3) or -6 (n-6) PUFA on gene expression, fatty acid (FA) composition and steroidogenesis in granulosa and theca cells and pre-implantation embryo development. A previous study in our laboratory reported increased follicular-fluid progesterone concentrations in ewes fed an n-3 compared to an n-6 PUFA-enriched diet, but detected no differential effect of n-3 and n-6 PUFA enriched high-density lipoproteins (HDL) on granulosa cell steroidogenesis in vitro. Also, n-6 PUFA enriched HDL reduced early embryo development, but in the absence of a net uptake of FA. In view of these observations it was hypothesised that (i) effects of n-3 PUFA on ovarian steroidogenesis are mediated by theca rather than granulosa cells and (ii) during embryo culture lipids are acquired solely from the albumin fraction of serum, so that albumin delivered n- 3 and n-6 PUFA would exert a greater differential effect on embryo development than either LDL or HDL delivered PUFA. Initial investigations into granulosa cell gene expression profiles using an ovine gonad-targeted cDNA macroarray were unsuccessful, highlighted by subsequent qRTPCR analysis. A thorough investigation confirmed that inconsistencies were due to poor array hybridisation. In vitro data confirmed that n-3 PUFA, via delivery by HDL, increase progesterone production solely in theca cells and that this is associated with an increase in STAR transcript expression. We also demonstrate that albumin is the only serum fraction that leads to a net uptake of FA during embryo culture. PUFA enriched serum and albumin accelerated the development of embryos and increased the yield of morphologically poorer quality blastocysts with increased transcript expression for the antioxidant enzyme SOD1. Important differential effects of n-3 and n-6 PUFA on ovarian steroidogenesis acting solely on theca cells are identified, but differentially effects of PUFA on embryo development are less apparent.

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Xavier, Roberta Araújo Navarro [UNIFESP]. "Modelos Experimentais de inflamação: Ação preventiva de dietas ricas em óleo de Soja ou Peixe na asma e nova estratégia para identificar drogas com proproedades pró-resolução." Universidade Federal de São Paulo (UNIFESP), 2009. http://repositorio.unifesp.br/handle/11600/9819.

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Made available in DSpace on 2015-07-22T20:50:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-09-30
A asma é uma doença crônica das vias aéreas caracterizada por obstrução do fluxo aéreo e intenso processo inflamatório, no qual, muitas células estão envolvidas, principalmente os eosinófilos. O processo inflamatório na asma pode induzir o aparecimento de alterações estruturais caracterizadas por fibrose subepitelial, hiperplasia da musculatura lisa das vias aéreas, neoformação vascular e remodelamento das vias aéreas. O aumento na prevalência da asma tem sido associado ao elevado consumo de ácidos graxos poliinsaturados do tipo Omega 6. A melhora dos sintomas apresentados por indivíduos asmáticos, por outro lado, foi observada em pacientes tratados com ácidos graxos poliinsaturados Omega 3. No mesmo segmento, alguns trabalhos da literatura têm relacionado efeitos antiinflamatórios benéficos à utilização de dietas enriquecidas com ácidos graxos poliinsaturados Omega 3, em processos inflamatórios agudos e crônicos. Nosso grupo não encontrou evidências do efeito pró-inflamatório dos ácidos graxos poliinsaturados Omega 6, previamente sugerido por vários autores. Nossos dados demonstram que a dieta rica em ácidos graxos poliinsaturados Omega 3, bem como a dieta rica em ácidos graxos poliinsaturados Omega 6, exercem efeito antiinflamatório sobre a inflamação aguda induzida por carragenina. Esse efeito antiinflamatório foi associado aos elevados níveis de corticosterona encontrados nesses animais. Neste trabalho, avaliamos a resposta inflamatória e a liberação de mediadores inflamatórios envolvidos na asma, em ratos alimentados com dietas enriquecidas com óleo de soja, ácidos graxos poliinsaturados Omega 6, ou óleo de peixe, ácidos graxos poliinsaturados Omega 3. Os resultados obtidos demonstram que, a dieta rica em ácidos graxos poliinsaturados Omega 6 não foi pró-inflamatória. Ao contrário, foi tão antiinflamatória quanto a dieta rica em ácidos graxos poliinsaturados Omega 3. Ambas diminuiram o infiltrado celular no lavado broncoalveolar, citocinas associadas ao perfil Th2, redução dos níveis de bradicina e aumento dos níveis de óxido nítrico. Além disso, a dieta rica em óleo de soja, aumentou os níveis de corticosterona e lipoxina A4 no pulmão dos animais alimentados com essa dieta. Com base nesses resultados, acreditamos que essas dietas possam contribuir para o estudo de terapias alternativas ou complementares, atuando em conjunto com as drogas utilizadas para o tratamento da asma.
TEDE
BV UNIFESP: Teses e dissertações

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Burkey, Carren Nyambare. "Bioprocessing of soybean seed-coats for production of proteins & omega-3 fatty acids using Pythium isolates." Bowling Green State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu159361093538274.

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Pappiani, Caroline. "Efeito dos ácidos graxos ômega-3, ômega-6 e ômega-9 sobre o risco cardiovascular de indivíduos adultos: estudo clínico de prevenção primária." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/6/6138/tde-02062016-145648/.

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INTRODUÇÃO: As doenças cardiovasculares (DCV) são a principal causa de morte no mundo, sendo muitos dos fatores de risco passíveis de prevenção e controle. Embora as DCV sejam complexas em sua etiologia e desenvolvimento, a concentração elevada de LDL-c e baixa de HDL-c constituem os fatores de risco modificáveis mais monitorados na prática clínica, embora não sejam capazes de explicar todos os eventos cardiovasculares. Portanto, investigar como intervenções farmacológicas e nutricionais podem modular parâmetros oxidativos, físicos e estruturais das lipoproteínas pode fornecer estimativa adicional ao risco cardiovascular. Dentre os diversos nutrientes e compostos bioativos relacionados às DCV, os lipídeos representam os mais investigados e descritos na literatura. Nesse contexto, os ácidos graxos insaturados (ômega-3, ômega-6 e ômega-9) têm sido foco de inúmeros estudos. OBJETIVOS: Avaliar o efeito da suplementação com ômega-3, ômega-6 e ômega-9 sobre os parâmetros cardiometabólicos em indivíduos adultos com múltiplos fatores de risco e sem evento cardiovascular prévio. MATERIAL E MÉTODOS: Estudo clínico, randomizado, duplo-cego, baseado em intervenção nutricional (3,0 g/dia de ácidos graxos) sob a fórmula de cápsulas contendo: ômega-3 (37 por cento de EPA e 23 por cento de DHA) ou ômega-6 (65 por cento de ácido linoleico) ou ômega-9 (72 por cento de ácido oleico). A amostra foi composta por indivíduos de ambos os sexos, com idade entre 30 e 74 anos, apresentando pelo menos um dos seguintes fatores de risco: Dislipidemia, Diabetes Mellitus, Obesidade e Hipertensão Arterial Sistêmica. Após aprovação do Comitê de Ética, os indivíduos foram distribuídos nos três grupos de intervenção. No momento basal, os indivíduos foram caracterizados quanto aos aspectos demográficos (sexo, idade e etnia) e clínicos (medicamentos, doenças atuais e antecedentes familiares). Nos momentos basal e após 8 semanas de intervenção, amostras de sangue foram coletadas após 12h de jejum. A partir do plasma foram analisados: perfil lipídico (CT, LDL-c, HDL-c, TG), apolipoproteínas AI e B, ácidos graxos não esterificados, atividade da PON1, LDL(-) e auto-anticorpos, ácidos graxos, glicose, insulina, tamanho e distribuição percentual da LDL (7 subfrações e fenótipo A e não-A) e HDL (10 subfrações). O efeito do tempo, da intervenção e associações entre os ácidos graxos e aspectos qualitativos das lipoproteínas foram testados (SPSS versão 20.0, p <0,05). RESULTADOS: Uma primeira análise dos resultados baseada em um corte transversal demonstrou, por meio da análise de tendência linear ajustada pelo nível de risco cardiovascular, que o maior tercil plasmático de DHA se associou positivamente com HDL-c, HDLGRANDE e tamanho de LDL e negativamente com HDLPEQUENA e TG. Observou-se também que o maior tercil plasmático de ácido linoleico se associou positivamente com HDLGRANDE e tamanho de LDL e negativamente com HDLPEQUENA e TG. Esse perfil de associação não foi observado quando foram avaliados os parâmetros dietéticos. Avaliando uma subamostra que incluiu indivíduos tabagistas suplementados com ômega-6 e ômega-3, observou-se que ômega-3 modificou positivamente o perfil lipídico e as subfrações da HDL. Nos modelos de regressão linear ajustados pela idade, sexo e hipertensão, o DHA plasmático apresentou associações negativas com a HDLPEQUENA. Quando se avaliou exclusivamente o efeito do ômega-3 em indivíduos tabagistas e não tabagistas, observou-se que fumantes, do sexo masculino, acima de 60 anos de idade, apresentando baixo percentual plasmático de EPA e DHA (<8 por cento ), com excesso de peso e gordura corporal elevada, apresentam maior probabilidade de ter um perfil de subfrações de HDL mais aterogênicas. Tendo por base os resultados acima, foi comparado o efeito do ômega-3, ômega-6 e ômega-9 sobre os parâmetros cardiometabólicos. O ômega-3 promoveu redução no TG, aumento do percentual de HDLGRANDE e redução de HDLPEQUENA. O papel cardioprotetor do ômega-3 foi reforçado pelo aumento na incorporação de EPA e DHA, no qual indivíduos com EPA e DHA acima de 8 por cento apresentaram maior probabilidade de ter HDLGRANDE e menor de ter HDLPEQUENA. Em adição, observou-se também que o elevado percentual plasmático de ômega-9 se associou com partículas de LDL menos aterogênicas (fenótipo A). CONCLUSÃO: Ácidos graxos plasmáticos, mas não dietéticos, se correlacionam com parâmetros cardiometabólicos. A suplementação com ômega-3, presente no óleo de peixe, promoveu redução no TG e melhoria nos parâmetros qualitativos da HDL (mais HDLGRANDE e menos HDLPEQUENA). Os benefícios do ômega-3 foram particularmente relevantes nos indivíduos tabagistas e naqueles com menor conteúdo basal de EPA e DHA plasmáticos. Observou-se ainda que o ômega-9 plasmático, presente no azeite de oliva, exerceu impacto positivo no tamanho e subfrações da LDL.
INTRODUCTION: Cardiovascular diseases (CVD) are the leading cause of death worldwide and many of the risk factors are likely to prevention and control. While CVD are complex in their etiology and development, a high concentration of LDL-c and low HDL-c are the most investigated modifiable risk factors in clinical practice, although they are not able to explain all cardiovascular events. So investigate how nutritional and pharmacological interventions can modulate oxidative, physical and structural parameters of lipoproteins can provide additional estimate for cardiovascular risk. Among the many nutrients and bioactive compounds related to CVD, lipids represent the most investigated and described in the literature. In this context, the unsaturated fatty acids (omega-3, omega-6 and omega-9) have been focus of numerous studies. OBJECTIVES: To evaluate the effect of supplementation with omega-3, omega-6 and omega-9 on cardiometabolic parameters in adults with multiple risk factors and without previous cardiovascular event. MATERIAL AND METHODS: Clinical trial, randomized, double-blind, based on nutritional intervention (3.0 g/day of fatty acids) containing: omega-3 (37 per cent EPA and 23 per cent DHA) or omega-6 (65 per cent linoleic acid) or omega-9 (72 per cent of oleic acid). Subjects of both sexes, aged between 30 and 74 years old, with at least one of the following risk factors: hyperlipidemia, diabetes mellitus, obesity and hypertension were included. After Ethics Committee approval, the subjects were distributed on the three intervention groups. At baseline the demographic (gender, age and ethnicity) and clinical (medications, current diseases and family history) data were evaluated. At baseline and after 8 weeks of intervention, blood samples were collected after 12 hours of fasting. From the plasma were analyzed: lipid profile (TC, LDLc, HDL-c, TG), apolipoproteins AI and B, non esterified fatty acid, PON1 activity, LDL (-) and autoantibodies, fatty acids, glucose, insulin, size and distribution of LDL (7 subfractions and phenotype) and HDL (10 subfractions). The effect of time, intervention and associations between fatty acids and qualitative aspects of lipoproteins were evaluated (SPSS version 20.0, p <0.05). RESULTS: A first analysis of the results based on a cross sectional study showed through the linear trend analysis, adjusted by the level of cardiovascular risk, that the highest tertile of plasma DHA was positively associated with HDL-c, HDLLARGE and LDL size and inversely with HDLSMALL and TG. The highest tertile of plasma linoleic acid was positively associated with HDLLARGE and LDL size and negatively with HDLSMALL and TG. This association was not observed when we evaluated the dietary parameters. A sample including smokers supplemented with omega-6 and omega-3 showed that omega-3 positively modify the lipid profile and HDL subfractions. In linear regression models adjusted for age, sex and hypertension, plasma DHA showed negative associations with HDLSMALL. When only assessed the effect of omega-3 in smokers and non-smokers, the results showed that smokers, male, over 60 years old, with low percentage of EPA and DHA (<8 per cent ), overweight and/or obese and high body fat have an increased chance to have HDL subfractions profile less cardioprotective. Based on the above results, we compared the effect of omega-3, omega-6 and omega-9 on cardiometabolic parameters. The omega-3 decreased TG, increase the percentage of HDLLARGE and decrease HDLSMALL. The cardioprotective role of the omega-3 was enhanced by increasing the incorporation of EPA and DHA, in which subjects with more than 8 per cent of EPA and DHA were more likely to have HDLLARGE and lower HDLSMALL. In addition, it was also observed that higher omega-9 plasma levels was associated with less atherogenic LDL particles (phenotype A). CONCLUSION: Plasma fatty acids, but not dietary, correlate with cardiometabolic parameters. Supplementation with omega-3, present in fish oil, promoted reduction in TG and improved the qualitative parameters of HDL (more HDLARGE and less HDLSMALL). The benefits of omega-3 were particularly significant in smokers and those with lower baseline content of EPA and DHA. It was also observed that omega-9, present in olive oil, had a positive impact on the size of LDL.

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Loucaides, George N. "The effects of Omega-3, Omega-6 Polyunsaturated Fatty Acids (PUFAs) and Vitamin E on patients with the remitting-relapsing (RR) form of Multiple Sclerosis (MS) in Cyprus." Thesis, London Metropolitan University, 2016. http://repository.londonmet.ac.uk/1169/.

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Multiple sclerosis is an inflammatory and demyelinating multifactorial disease that results from the interplay between environmental factors and a susceptible genetic background. Omega (ω)-3/ω-6 polyunsaturated fatty acids (PUFAs) and some vitamins have been shown to reduce the number and severity of relapses and the overall progression of disability in multiple sclerosis patients, however clinical trials remain inconclusive due to a plethora of reasons. In this randomized, double blinded, placebo controlled trial aiming to provide concrete conclusions for the role of PUFAs and vitamins A and E (both gamma (γ) and alpha (α)) in multiple sclerosis. By measuring the incorporation and changes of the lipid composition in red blood cell (RBC) membranes before and after the dietary intervention, and by correlating the efficacy of the different interventions with disease progression, it was shown that supplementation with these specific molecules (that can either act on their own or synergistically) could probably cause the decrease of arachidonic acid (AA) and linoleic acid (LA) from the RBC membranes and the subsequent substitution by eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These events parallel the clinical observations where this can be correlated with the increased number of relapse activity occurring in the first six months of treatment and later with a prolonged period of remission. Supplementation with the mixture of PUFAs (both ω3 and ω6), vitamin E as gamma tocopherol significantly reduced the annualised relapse rate (ARR) and the risk of sustained disability progression without any reported serious adverse events.

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López, Vicario Cristina. "La importancia del balance en ácidos grasos omega-3 y omega-6 en la esteatohepatitits no alcohólica asociada a la obesidad." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/396210.

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INTRODUCCIÓN: Los ácidos grasos poliinsaturados (PUFA) son lípidos de membrana que confieren propiedades estructurales y fisiológicas a la célula. Los PUFA son considerados ácidos grasos esenciales porque nuestro organismo los obtiene a través de la dieta. Se clasifican en dos grandes famílias: omega-6 y omega-3. Ambas comparten 3 rutas biosintéticas para la formación de medidadores lipídicos de la inflamación: ciclooxigenasas, lipoxigenasas y citocromo P450 (CYP). La competencia existente entre los omega-6 y los omega-3 por las mismas vías puede generar desequilibrios metabólicos. Una relación omega-6/omega-3 elevada consecuente de un exceso de omega-6 en la dieta puede contribuir al desarrollo de enfermedades que cursan con inflamación. Los ratones fat-1 representan un modelo animal transgénico con una relación omega-6/omega-3 equilibrada debido a la presencia del gen fat-1 procedente del nematodo C. elegans. Este gen, ausente en mamíferos, codifica para la enzima omega-3 desaturasa que cataliza la conversión de los omega-6 en omega-3 permitiendo el enriquecimiento de los tejidos con omega-3. La enfermedad del hígado graso de origen no alcohólico (EHGNA) es un síndrome con etiología multifactorial que incluye un amplio espectro de anormalidades hepáticas que van desde la esteatosis hasta la esteatohepatitis no alcohólica (EHNA), y en algunos casos puede progresar a cirrosis hepática. La prevalencia de EGHNA está aumentando a nivel mundial paralelamente con el aumento de la obesidad. Desde que la obesidad es un problema emergente de salud pública, la identificación de nuevas estrategias terapéuticas es primordial para la prevención y el tratamiento de enfermedades metabólicas asociadas a la obesidad. OBJETIVOS: El objetivo esencial de este trabajo es investigar la efectividad de un balance equilibrado entre los PUFA omega-6 y omega-3 en la prevención de la EHGNA asociada a la obesidad mediante la utilización del modelo de ratón transgénico fat-1. RESULTADOS: Los resultados del primer estudio indican que el enriquecimiento tisular con omega-3 mediante la expresión transgénica del gen fat-1 representa efectos protectores frente a la EHNA. El restablecimiento del balance omega-6/omega-3 acompañado de intervenciones farmacológicas dirigidas a enzimas específicas delta-5/delta-6/delta-9 desaturasas producen un efecto protector sobre la esteatosis hepática y la inflamación. Los resultados del segundo estudio demuestran que la estabilización de los epóxidos derivados de los omega-3 generados a partir del CYP mediante la inhibición de la epóxido hidrolasa soluble (sEH) ejerce efectos beneficiosos en contrarrestar los desórdenes metabólicos asociados con la obesidad. Además, este estudio lanza más luz sobre el papel de la sEH en la homeostasis celular mostrando evidencias que los epóxidos de los omega-3 y la inhibición de la sEH regula la autofagia en los tejidos sensibles a la insulina, especialmente en el hígado. CONCLUSIÓN: Este proyecto de investigación pone de manifiesto que la modulación de la composición tisular en mediadores lipídicos derivados de los omega-3 para reestablecer el balance omega-6/omega-3 representa una estrategia prometedora en la prevención y la terapia de las comorbilidades relacionadas con la obesidad, como es el caso de la esteatohepatitis no alcohólica.
Polyunsaturated fatty acids (PUFA) are membrane lipids that confer structural and physiological properties to the cell. PUFA are considered essential fatty acids because are obtained through the diet. PUFA are classified in omega-6 and omega-3 and both types share the same pathways for the synthesis of lipid mediators: ciclooxygenases, lipoxygenases and cytochrome P450 (CYP). The competition between omega-3 and omega-6 for the same pathways could lead to metabolic unbalance. High intakes of the inflammatory omega-6 accompanied by a decrease in the amount of the anti-inflammatory omega-3 in the diet could contribute to the progression of inflammatory diseases. Fat-1 mice have a balanced omega-6/omega-3 ratio because they express the fat-1 gene from C.elegans. This gene encodes an omega-3 desaturase that catalyzes the conversion of omega-6 fatty acids into the omega-3. Nonalcoholic fatty liver disease (NAFLD) is a multifactorial disorder that includes a wide spectrum of hepatic manifestations ranging from fatty liver or hepatic steatosis to nonalcoholic steatohepatitis (NASH) in which hepatic steatosis is accompanied by inflammation. Obesity and insulin resistance are the best known risk factors for NAFLD. Since prevalence of obesity is an emerging public health issue, identifying novel targets in NAFLD is of paramount importance in the prevention of metabolic liver disease. The aim of this work is to investigate the effect of a balanced omega-6/omega-3 ratio in the prevention of obesity-induced NAFLD by using transgenic fat-1 mice. The results of the first study indicate that omega-3 tissue enrichment represent protective actions against NASH. The restoration of the omega-6/omega-3 ratio accompanied by pharmacological interventions of delta-5/delta-6/delta-9 desaturases produces anti-steatotic and anti-inflammatory effects. The results of the second study demonstrate that stabilization of CYP metabolites derived from omega-3 fatty acids through inhibition of the enzyme soluble epoxide hydrolase exerts beneficial actions in cellular homeostasis by regulation autophagy and endoplasmic reticulum stress in insulin-sensitive tissues, especially liver and adipose tissue. In conclusion, these findings strongly support that modulation of tissue lipid composition to restore the omega-6/omega-3 ratio represent a promising strategy to prevent obesity-related comorbidities, such as fatty liver disease.

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Granberg, Ebba. "Fleromättade fetter, torra ögon och Sjögrens syndrom : Kan en kost rik på omega 3 och 6 lindra symtomen vid Sjögrens syndrom och torra ögon?" Thesis, Linnéuniversitetet, Institutionen för kemi och biomedicin (KOB), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-79447.

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Introduktion: Torra ögon (DES) och Sjögrens syndrom (SjS) är inflammatoriska sjukdomar som drabbar ögonen. DES drabbar tårkörtelns funktionella del vilket ger ögonsmärta och suddig syn. SjS är en kronisk autoimmun sjukdom som ger skada på tår- och salivproducerande körtlar. Det leder till kliniska symtom i form av mun- och ögontorrhet. Essentiella fettsyror bildar proinflammatoriska och antiinflammatoriska cytokiner som kan hjälpa vid behandling av dessa sjukdomar. Metod och syfte: En litteraturstudie genomfördes för att ta reda på om fleromättade fetter kan lindra symtomen vid SjS och DES. Resultat: Resultaten för studierna visade resultat på OSDI, Schirmers test, BUT, IL-17, tårosmolaritet, tårvolym, ostimulerat salivflöde, stimulerat salivflöde, sonderingsdjup, PGE1, van Bijstervelds poäng och flourscein infärgning. Diskussion: Resultatet visar signifikanta skillnader för vissa doser av n-3 och n-6. Det som skiljer resultaten åt är de olika doserna av fettsyror samt vad dess placebokontroller intog. OSDI visade främst skillnader på de patienter med DES men endast på en grupp med SjS som intog n-3 för behandling av torr mun. Schirmers test och BUT visade en ökning hos patienterna med mild och måttlig DES men inte på patienterna med SjS. Patienterna med SjS visade förbättringar på stimulerat salivflöde och OSDI för torr mun samt PGE1 nivåer och flourscein infärgning samtidigt som en del studier inte visade några signifikanta förbättringar på några mätvariabler. Det kan grunda sig i intaget av fettsyror, sjukdomstillstånd eller längden på behandling. Slutsats: En del personer kan få förbättrade symtom av att inta n-3 eller n-6 tillskott men skillnaderna är inte alltid statistiskt signifikanta för studierna.
Introduction: Dry eye syndrome (DES) and Sjögren ́s syndrome (SjS) are inflammatory diseases that affect the eyes. DES affects the lacrimal glands functional unit, causing eye pain and blurred vision. SjS is a chronical autoimmune disease that causes damage to tear and salivary glands. It leads to clinical symptoms in the form of mouth and eye irritation. Essential fatty acids form pro-inflammatory and anti-inflammatory cytokines that can help in the treatment of these diseases. Method and purpose: A literature study was performed to study if essential fatty acids can relieve the symptoms of DES and SjS. Results: The results for the studies showed results on OSDI, Schirmer ́s test, BUT, IL- 17, tear osmolarity, tear volume, unstimulated salivary flow, stimulated salivary flow, depth of probing, van Bijsterveld ́s score and flourscein staining. Discussion: The result shows significant differences for certain doses of n-3 and n-6. What separates the results are the different doses of fatty acids and what their placebo controls took. OSDI showed major differences in patients with DES but only in one group of patients with SjS who took n-3 for treating dry mouth. Schirmer ́s test and BUT showed an increase in patients with mild and moderate DES but not in patients with SjS. Patients with SjS showed improvements in stimulated salivary flow, dry mouth OSDI, PGE1 levels and flourscein staining, while some studies did not show any significant improvements in any measurement variables. It may be due to the intake of fatty acids, disease states or the length of treatment. Conclusion: Some people may get improved symptoms of taking n- 3 or n-6 supplements, but the differences are not always statistically significant for the studies.

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Farooq, Muhammad Akmal. "Potential of omega-3 EPA/DHA 6/1 to ameliorate ageing-related endothelial dysfunction." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAJ107/document.

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La présente étude évalue la capacité de la formulation d’oméga-3 EPA:DHA 6:1, une formulation capable d’induire la formation continue de monoxyde d’azote par la NO synthase endothéliale, à améliorer la dysfonction endothéliale liée à l’âge établie chez le rat. La dysfonction endothéliale liée à l’âge est caractérisée par une altération des composantes de la relaxation et une augmentation des réponses contractiles dépendantes de l’endothélium. L’âge augmente le stress oxydant vasculaire, l’expression de la NADPH oxydase, COX-2, eNOS, ACE, AT1R, et des marqueurs de senescence, alors que la COX-1 est sous-exprimé. La formulation EPA:DHA 6:1 améliore la composante NO, diminue l’EDCF et le stress oxydant vasculaire, et normalise l’expression des protéines cibles. En conclusion, la consommation chronique de EPA:DHA 6:1 améliore la dysfonction endothéliale liée à l’âge chez le rat, probablement en prévenant l’activation du système angiotensine locale et le stress oxydant en résultant
EPA:DHA 6:1 omega-3 formulation has been shown to induce a sustained endothelial NO synthase-derived formation of nitric oxide. This study examined if the intake of EPA:DHA 6:1 improves an established ageing-related endothelial dysfunction. Ageing-related endothelial dysfunction was characterized by a blunted NO-mediated component of relaxation, abolished EDH-mediated component and increased COX-derived endothelium-dependent contractile responses. Ageing increased vascular oxidative stress, expression of NADPH oxidase subunits, COX-2, eNOS, ACE, AT1R, and senescence markers, whereas COX-1 was down-regulated. Chronic intake of EPA:DHA 6:1 improved the NO-mediated relaxations, reduced EDCFs, vascular oxidative stress and normalized the expression of protein markers. In conclusion, chronic intake of EPA:DHA 6:1 prevented the ageing-related endothelial dysfunction in old rats, most likely by preventing activation of the local angiotensin system and the subsequent vascular oxidative stress

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Moreira, Ana Vládia Bandeira. "Efeito antioxidante dos compostos fenólicos de especiarias sobre os ácidos graxos das séries ω 3 e ω 6." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/9/9131/tde-15072014-150247/.

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Dentro da perspectiva da utilização de compostos fenólicos como antioxidantes naturais para minimizar os efeitos in vitro e in vivo do processo oxidativo dos lípides insaturados, foi realizada a monitoração dietética de duas dietas ricas em lípides das séries ω3 e ω6 e a suplementação de um chá de uma mistura de especiarias, em ratos Wistar, com o objetivo de verificar a influência dos compostos fenólicos, presentes nas especiarias, sobre o metabolismo de ácidos graxos das séries ω3 e ω6. Extratos e frações das especiarias mostarda, canela e erva doce foram obtidos e tiveram suas atividades antioxidantes testadas em sistemas aquoso (cooxidação de substratos com o uso de ácido linoléico/β-caroteno) e lipídico (RANCIMAT) e o perfil de compostos fenólicos identificados e quantificados por CGMS. A partir de uma mistura de especiarias, foi elaborado um chá que foi fornecido aos animais de cada grupo dietético (ω3 e ω6). Após 45 dias de tratamento, os animais foram sacrificados e tiveram seus tecidos coletados para análise de TBARs e do perfil lipídico por CGMS. Todos os extratos das especiarias apresentaram atividade antioxidante equivalente ou superior ao BHT. Foram identificados por CGMS os ácidos fenólicos: catecol, salicílico e caféico. Foi obtido nos tecidos dos animais que o somatório do perfil de ácidos graxos saturados e dos insaturados apresentaram diferença entre os grupos testes e controles. Logo, no tecido cerebral, o EPA foi incorporado apenas no grupo ω3 que recebeu o extrato das especiarias. Já para o DHA, do mesmo grupo dietético, os tecidos hepático e renal também apresentaram incorporação aumentada em relação ao controle. No grupo dietético ω6, destaca-se um aumento no percentual de incorporação do ácido linoléico nos tecidos cardíaco e renal no grupo experimental. Enquanto, para o ácido araquidônico, houve diferença em todos os tecidos. Já, para os resultados da lipoperoxidação, observou-se que todos os tecidos dos animais que receberam o extrato das especiarias apresentaram baixos valores em comparação aos seus respectivos controles. Este estudo também avaliou a ação de compostos fenólicos do chá da mistura das especiarias mostarda, canela e erva doce sobre as enzimas lipoxigenase e cicloxigenase. O extrato da mistura das especiarias a 100 e 200 ppm foi adicionado no meio de reação contendo o substrato e a enzima lipoxigenase 1B da Sigma com 112.000 und/mg. A cicloxigenase foi obtida de vesículas seminais de carneiro e seguiu-se o mesmo protocolo de atividade para a lipoxigenase. Indometacina foi o inibidor utilizado como controle positivo da reação. Observou-se que a 200 ppm, como na concentração do chá (0,02%), a lipoxigenase foi inibida em aproximadamente em 90%. Já para a cicloxigenase, o extrato a 200 ppm resultou numa média de 75% de inibição da atividade da enzima, enquanto que a indomentacina apresentou uma média de 77% de inibição. A absorção aparente do chá das especiarias indicou que os fenólicos presentes na mistura foram absorvidos em média de 75%. O estudo histopatológico dos intestinos delgados dos animais não apresentou nenhuma diferença na área de absorção entre o grupo experimental e o controle. Estes dados sugerem, portanto, um efeito antioxidante das substâncias fenólicas identificadas nas especiarias sobre os ácidos graxos das séries ω3 e ω6, podendo agir diretamente: (1) no alimento (óleo), (2) com modificação do perfil lipídico, (3) proteção quanto à oxidação de tecidos e (4) inibição das enzimas da biossíntese dos eicosanóides.
Considering the perspective for the use of phenolic compounds as natural antioxidants to minimize in vitro and in vivo effects of oxidative processes on unsaturated lipids, this work monitored Wistar rats fed with two diets rich in ω3 and ω6 polyunsaturated lipids, supplemented with tea made from a blend of spices. The objective of the work was to study the influence of phenolic compounds present in spices on the metabolism of ω3 and ω6 fatty acids. Extracts and fractions of mustard, cinnamon and anise were obtained and had their antioxidant activity tested in aqueous (co-oxidation of substrates using linoleic acid/β-carotene) and lipidic systems (RANCIMAT). Their phenolic compounds profile was determined and quantified using CGMS. The rats of each diet group (ω3 and ω6) were given tea made from a blend of spices and sacrificed after 45 days. Their tissues were then collected and analyses of TBARS and lipid profile were performed using CGMS. Ali the extracts of spices showed equal or higher antioxidant activity than BHT. The following phenolic acids were identified using CGMS: cathecol, salicilic and cafeic. It was observed that the total amount of the profile of saturated and unsaturated fatty acids in the rat tissues were different in the test group and the control group. In brain tissue, EPA was found only in the ω3 diet group which was given the tea. Concerning DHA, liver and kidney tissues of the same diet group showed higher concentrations than the control group. In the ω6 diet group, an outstanding increase of linoleic acid in cardiac and kidney tissues was found. Concerning the arachidonic acid, a difference in concentration was observed in ali tissues. Ali the tissues from rats given the tea presented a lower level of lipid peroxidation than their respective control groups. The present research also evaluated the action of phenolic compounds found in the tea made from the blend of mustard, cinnamon and anise on the enzymes lipoxygenase and cycloxygenase. The extract of the blend of spices, in the concentrations of 100 and 200 ppm, was added to the substrate and Sigma lipoxygenase 112.000 units/mg. Cycloxygenase was obtained from sheep seminal bladders and underwent the same protocol as lipoxygenase. Indomethacin was the inhibitor used as the positive control of the reaction. It was observed that in the concentration of 200 ppm (that is 0.02%, the same concentration as in the tea), lipoxygenase presented an average 90% inhibition. The extract of cycloxygenase 200 ppm presented 75% inhibition of the enzyme activity, while indomethacin presented an average 77% inhibition. It was found that around 75% of the phenolic compounds present in the tea made from the blend of spices were absorbed, thus leading to the conclusion that apparent absorption of the tea took place. Histopathologic examinations on the small intestines of the rats did not reveal any difference in the absorption area between the experimental and the control groups. Such results suggest therefore an antioxidant effect of the phenolic substances identified in the spices on the ω3 and ω6 fatty acids, this effect being possible directly (1) on the food (oil) , (2) modification of the profile fatty acids, (3) oxidation protection tissues and, (4) inhibition of enzymes of eicosanoids biosinthesys.

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Wallingford, Sarah. "Investigations into the epidemiology and aetiology of cancers of the skin." Thesis, University of Manchester, 2014. https://www.research.manchester.ac.uk/portal/en/theses/investigations-into-the-epidemiology-and-aetiology-of-cancers-of-the-skin(97008a57-643e-4244-85c1-4e0a753e4d6f).html.

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The cancers of the skin, melanoma and the keratinocyte cancers, basal cell andsquamous cell carcinomas (BCC and SCC), are among the most common cancersin white populations. While ultraviolet radiation (UVR) is their principal cause,links with non-UVR-related factors have also been noted. Ultimately, theinteraction of these elements results in malignancy however, understanding oftheir specific contributions remains incomplete. This thesis reports findings fromsix studies aiming to investigate gaps in current knowledge of the role of UVR andnon-UVR-related risk factors on skin cancer. The papers are groupedaccording to the aspects of skin cancer epidemiology and aetiology they address. The first two papers address the descriptive epidemiology of melanoma inEngland, a country with low ambient solar UVR. They arise from ecologicalstudies using national melanoma registration data and document rising trends inmelanoma incidence by anatomic site (Paper 1), and by region of residence andsocio-economic deprivation (Paper 2). Their findings were consistent with thesuggestion that increases in recreational UVR exposure are driving rises inmelanoma rates. These results emphasise both the need to closely monitor UVRexposure and melanoma trends and the importance of public health campaigns. The second group of three papers considers the assessment of associations ofnutritional factors with keratinocyte cancer. Two studies use data from aprospective cohort to evaluate the relationship between dietary intake (Paper 3)and blood concentrations (Paper 4) of omega-3 and omega-6 polyunsaturatedfatty acids (PUFA) in relation to BCC and SCC risk. Associations with both PUFAtypes were observed. In addition, Paper 5, a three-way correlational assessment,demonstrated that questionnaire and blood circulating levels of omega-3 PUFAwere highly correlated with measures of skin bioavailability. Collectively, thesestudies give evidence for associations of these nutrients with skin cancer and forthe utility of both intake and biomarker measures for assessing the relationships. The final paper explores the relationship between a widely cited non-UVR riskfactor, namely scars and cancers of the skin. It reports a systematic review of allpublished observational studies quantifying this association. While innumerablecase reports were found, quantitative analyses were rare. The review identifieda major gap in the literature where knowledge of scar malignancies is notevidence-based, but rather founded mainly on cumulative anecdotal reporting. Taken together, this body of published work highlights the largely unrecognisedcomplexity of the aetiology of cancers of the skin. Future research must bebroad in scope in order to advance understanding of the interaction betweenUVR and other risk factors and to provide a base for health messages aimed atreducing the burden of these malignancies.

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Dagmey, Aurélien. "Enrichissement d’huiles alimentaires riches en acides gras polyinsaturés, par des composés phénoliques d’origine naturelle, afin de les protéger de la peroxydation lipidique, en vue d’une encapsulation pour augmenter la durée de conservation de ces huiles." Thesis, Compiègne, 2020. http://bibliotheque.utc.fr/EXPLOITATION/doc/IFD/2020COMP2553.

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Les acides linoléique (LA) et α-linolénique (ALA) sont deux acides gras polyinsaturés. Ils sont indispensables à l’Homme car nous sommes incapables de les synthétiser in situ. Ces deux acides gras sont les représentants des oméga-6 (LA) et oméga-3 (ALA). Bien qu’ils soient indispensables et donc nécessaires, l’enjeu du ratio oméga-6/oméga-3 entre ces deux familles est également important à prendre en compte dans l’alimentation. Les habitudes de consommation des Français, ces trente dernières années, ont fait évoluer la balance en défaveur des oméga-3 par rapport aux oméga-6. Or un rééquilibre de la balance oméga-6/oméga-3 tend à diminuer les risques cardiovasculaires. Les huiles de lin et de cameline sont des cultures endémiques en France extrêmement riches en ALA. Elles sont les plus adaptées à une complémentation en oméga-3 d’origine végétale. Cependant, les hautes teneurs en acides gras polyinsaturés de ces huiles sont responsables de leurs faibles stabilités oxydatives. La consommation d’huiles ou de graisses oxydées n’est pas recommandée car elle peut apporter des molécules toxiques. Ainsi l’enjeu de ce projet était d’améliorer la durée de conservation d’huiles riches en acides gras polyinsaturés en valorisant les antioxydants extraits des tourteaux obtenus après trituration des graines. Parmi les molécules étudiées, l’acide gallique, l’acide caféique, le gallate de propyle ainsi que les pinorésinol et laricirésinol purifiées du lin ont montré un réel intérêt pour ralentir l’oxydation, tandis que le sécoisolaricirésinol s’est montré inefficace
Linoleic (LA) and α-linolenic (ALA) acids are two polyunsaturated fatty acids. They are essential for humans because we are unable to synthesize them in situ. These two fatty acids are the representatives of omega-6 (LA) and omega-3 (ALA). Although they are essential and therefore necessary, the issue of the omega-6 / omega-3 ratio between these two families is also important to take into account in the diet. The consumption habits of the French over the past thirty years have shifted the balance against omega-3s compared to omega-6s. Or a rebalancing of the omega-6 / omega-3 balance tends to reduce cardiovascular risks. Linseed and camelina oils are endemic crops in France extremely rich in ALA. They are the most suitable for supplementation with omega-3 of plant origin. However, the high contents of polyunsaturated fatty acids in these oils are responsible for their low oxidative stabilities. The consumption of oxidized oils or fats is not recommended because they can contribute toxic molecules. The aim of this project was to improve the shelf life of oils rich in polyunsaturated fatty acids by enhancing the antioxidant extracts of the cakes obtained after crushing the seeds. Among the molecules studied, gallic acid, caffeic acid, propyl gallate as well as pinoresinol and lariciresinol purified from flax showed a real interest in slowing down oxidation, while secoisolariciresinol was ineffective

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Inácio, Alexandre Guimarães. "Avaliação da estabilidade oxidativa do óleo de chia microencapsulado." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2194.

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CAPES
O óleo de chia vem sendo amplamente estudado devido aos seus benefícios para a saúde humana, sendo fonte de ácidos graxos essenciais como o ômega-3 e ômega-6, além de diversos compostos antioxidantes. Contudo, assim como outros óleos ricos em ácidos graxos insaturados, ele possui baixa estabilidade oxidativa. A encapsulação do óleo de chia é uma alternativa para protegê-lo da luz e do oxigênio, fatores determinantes para o início das reações de degradação. O impacto da encapsulação sobre a proteção do óleo deve ser mensurado e no estudo de óleos e gorduras as técnicas de análise térmica vem ganhando destaque nos últimos anos devido a rapidez, precisão e facilidade de operação. Neste trabalho, o óleo de sementes de chia foi microencapsulado em cera de carnaúba e sua estabilidade térmica foi avaliada. Primeiramente, as micropartículas foram caracterizadas por Espectroscopia no Infravermelho Médio, Difração de Raios-X, Cromatografia Gasosa e Microscopia Eletrônica de Varredura, sendo verificado um alto índice de eficiência de encapsulação (97%), apresentando tamanhos micrométricos, formato esférico e sem fissuras. Calorimetria Diferencial de Varredura (DSC) foi utilizada nos modos isotérmico e não isotérmico a fim de determinar os parâmetros de Arrhenius do óleo in natura e microencapsulado. Foi possível verificar a efetiva proteção do óleo de chia conferida pelas micropartículas de cera de carnaúba, sendo detectado um aumento na temperatura de indução oxidativa de até 26º C nos ensaios não isotérmicos. As micropartículas contendo o óleo também foram submetidas ao ensaio de estabilidade acelerada em estufa. Os espectros obtidos através do Uv-Vis foram utilizados para análise quimiométrica e na determinação dos coeficientes de extinção a 232 e 270 nm, corroborando o aumento da estabilidade oxidativa observado nos ensaios calorimétricos.
Chia oil has been widely studied because of its benefits to human health, being source of important fatty acids like omega-3 and omega-6, in addition to several antioxidant compounds. However, like other oils rich in unsaturated fatty acids, it has low oxidative stability. The encapsulation of chia oil is an alternative to protect it from light and oxygen, factors that determine the beginning of degradation reactions. The impact of encapsulation on oil protection should be measured and in the study of oils and fats the techniques of thermal analysis have been gaining prominence in recent years due to the speed, precision and ease of operation. In this work, the oil of chia seeds was microencapsulated in carnauba wax and its thermal stability was evaluated. Firstly, the microparticles were characterized by Medium Infrared Spectroscopy, X-Ray Diffraction, Gas Chromatography and Scanning Electron Microscopy. A high encapsulation efficiency index (97%) was verified, presenting micrometric sizes, spherical shape without cracks. Differential Scanning Calorimetry (DSC) was used in isothermal and non-isothermal modes in order to determine the Arrhenius parameters of the natural and microencapsulated oil. It was possible to verify the effective protection of the chia oil conferred by the microparticles of carnauba wax, and an increase in the oxidative induction temperature of up to 26º C was detected in non-isothermal tests. The microparticles containing the oil were also subjected to the schaal oven test and the spectra obtained through Uv-vis were evaluated by chemometrics and determination of the extinction coefficients at 232 and 270 nm, corroborating the increase in the oxidative stability observed in the calorimetric assays.

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Kiezel-Tsugunova, Magdalena. "Elucidating the metabolism of n-3 polyunsaturated fatty acids and formation of bioactive lipid mediators in human skin." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/elucidating-the-metabolism-of-n3-polyunsaturated-fatty-acids-and-formation-of-bioactive-lipid-mediators-in-human-skin(773abedd-c726-4dab-890a-694a96b1c074).html.

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Human skin has distinct lipid metabolism and production of bioactive lipid mediators that can be modulated by nutritional supplementation with omega-3 polyunsaturated fatty acids (n-3 PUFA), of which eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids exert anti-inflammatory effects. The aims of this project were to gain better understanding of their individual mechanisms in human epidermis and dermis. HaCaT keratinocytes, 46BR.1N fibroblasts, primary human epidermal keratinocytes and dermal fibroblasts were treated with EPA or DHA for 72h and then sham-irradiated or exposed to 15 mJ/cm2 ultraviolet radiation (UVR). Viability was measured by the MTT assay. The expression of cyclooxygenase-2 (COX-2), microsomal prostaglandin synthase-1 (mPGES-1) and 15-hydroxyprostaglandin dehydrogenase (15-PGDH) proteins was explored by western blotting. Human skin explants (n=4 donors) were cultured for 3 or 6 days and supplemented with EPA, DHA or vehicle. Culture media were collected to evaluate tissue damage and PUFA cytotoxicity (lactate dehydrogenase assay). Epidermal and dermal lipid profiles were assessed by gas chromatography and liquid chromatography coupled to tandem mass spectrometry. Primary keratinocytes were treated with fatty acids and various lipid mediators for 48h. Their effect was determined by the scratch assay and transepithelial electrical resistance. UVR upregulated COX-2 in HaCaT and primary epidermal keratinocytes, but did not affect mPGES-1 and 15-PGDH protein expression. UVR upregulated COX-2 and mPGES-1 in 46BR.1N fibroblasts but had no effect on 15-PGDH expression. The same UVR dose did not alter the expression of COX-2, mPGES-1 and 15-PGDH in primary dermal fibroblasts. Only EPA attenuated COX-2 expression in HaCaT and primary keratinocytes and either EPA or DHA had any effect in 46BR.1N and primary fibroblasts. Skin explants showed initial post-biopsy tissue damage. EPA and DHA supplementation augmented cellular levels of the corresponding fatty acids in both epidermis and dermis to a different extent. Increased uptake of DHA in the dermis was accompanied by reduced arachidonic acid levels. EPA treatment stimulated the production of PGE3 and various HEPE in epidermis, while DHA treatment caused high levels of HDHA species in dermis. N-3 PUFA and their derivatives delayed wound healing, cell migration and epidermal barrier permeability, while n-6 PUFA lipids showed the opposite effect. Overall, these findings suggest that EPA and DHA differently affect skin cells and skin, with EPA preference in epidermis and DHA in the dermis. These results highlight the importance of differential skin responses that could be important in skin health and disease.

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Hallott, Amanda Jane. "Blood cell fatty acids of pregnant women with Type 2 diabetes mellitus (T2DM) and gestational diabetes mellitus (GDM) : the influence of vitamin E supplementation alongside omega 3 and 6 fatty acids, in vitro, on LCPUGA incorporation into phospholipids and metabolism." Thesis, London Metropolitan University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.549557.

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Mimoun, Myriam. "Statut en AGPI et bénéfices d'une nutrithérapie à base de GPL-DHA chez un modèle murin de mucoviscidose." Thesis, Aix-Marseille 2, 2010. http://www.theses.fr/2010AIX20652/document.

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La mucoviscidose est une maladie génétique présentant des altérations ioniques causées par une protéine membranaire défectueuse ou inexistante la CFTR entraînant des perturbations métaboliques. Nous sommes intéressés à l’altération du métabolisme des acides gras polyinsaturés (AGPI) n-3 et n-6, caractérisé par une déficience en acides linoléique (LA) et docosahexaénoïque (DHA) et une élévation de l’acide arachidonique (AA). Ce déséquilibre peut être préjudiciable à l’état des patients du fait du rôle clé de certains AGPI à différents niveaux de la vie. Nos travaux ont portés sur la recherche des bénéfices d’un vecteur riche en un AGPI n-3 d’intérêt, le DHA, dans le contexte de la mucoviscidose à travers deux approches : une approche par supplémentation réalisée chez un modèle murin présentant la mutation la plus répandue chez les patients, et une approche sur un modèle d’entérocyte humain afin d’étudier de façon plus approfondie l’intérêt du supplément sur la fonctionnalité cellulaire (absorption des nutriments lipidiques). Nos résultats nous ont conduits à différentes conclusions : les souris delF508 nourries avec du Peptamen Junior présentent une perturbation du métabolisme des n-6 (LA, AA) dès l’âge de 3 mois ; cette altération apparaît mais plus tard sous régime standard. Par contre, quelque soit le régime alimentaire notre modèle ne développe pas de déficience en DHA jusqu’à l’âge d’1 an. L’évolution du statut en AGPI n-6 est donc dépendante du régime et de l’âge. L’apport de glycérophospholipides enrichis en DHA administré à faible dose permet de corriger les perturbations en AGPI n-6 et d’augmenter le rapport en DHA/AA dans la plupart des organes. Ce vecteur s’avère potentiellement intéressant en nutrithérapie chez le patient. Un enrichissement physiologique en DHA de l’entérocyte ne modifie pas ses capacités absorptives qui sont plutôt régulées par le type de particules véhiculant les produits de lipolyses, micelles de sels biliaires versus liposomes
Cystic fibrosis is a genetic disease showing ionic alterations, caused by an absent or defective membrane protein CFTR leading to metabolic disturbances. We are interested in n-6 and n-3 polyunsaturated fatty acid (PUFA) metabolism alteration characterized by a linoleic (LA) and docosahexaenoic (DHA) acids deficiency and high level of arachidonic acid (AA). This imbalance can affect patient health due to the key role of some PUFAs in different levels of life. Our studies focused on finding the benefits of a vector enriched in one interesting n-3 PUFA, DHA, in context of cystic fibrosis, through two approaches: a nutritional supplementation conducted in a mouse model with the most common mutation of cystic fibrosis patients, and an approach on a model of human enterocyte to investigate more thoroughly the effect of the vector on cell functionality (absorption of lipid nutrients). Our results led us to different conclusions: del F508 mice fed with Peptamen Junior have a metabolic disorder of the n-6 PUFA (LA, AA) at the age of 3 months, but this alteration appears later under standard regime . But, whatever the diet, our model does not develop a DHA deficiency to the age of 1 year. The changing status of n-6 is dependent on diet and age. Glycerophospholipids enriched in DHA given at low doses can correct disturbances in PUFA n-6 and increase the DHA/AA ratio in most organs. This vector is potentially interesting for a patient nutritherapy. A physiological DHA enrichment of enterocyte does not alter its absorption capacity, which is rather regulated by the type of particles carrying the lipolysis products, bile salt micelles versus liposomes

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Mariniello, Katia. "Comparative study of synthesis and incorporation of omega-3 and 6- long chain polyunsaturated fatty acids by THP-1 and HT29 cells with a specifc focus on the influence of retinoids." Thesis, London Metropolitan University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.540612.

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Broughton, Richard. "Omega 3 fatty acids : identification of novel fungal and chromistal sources." Thesis, Royal Holloway, University of London, 2012. http://repository.royalholloway.ac.uk/items/38797691-c5ac-ef52-3a6c-12c3097e2765/6/.

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There is a wealth of scientific evidence associating the dietary intake of omega 3 long-chain polyunsaturated fatty acids with beneficial health properties. In this study, alternative natural sources of these polyunsaturated fatty acids are sought from novel low temperature isolated fungi. Over 100 low temperature isolated fungi were screened for very long chain polyunsaturated fatty acids (VLCPUF As), such as C20:5 n3 and C22:6 n3. Of those screened, only ten fungi were capable of VLCPUFA production, with Mortierella the predominant VLCPUF A producing species. Four Oomycete species were also capable of VLCPUF A production. It is thought that only basal fungal lineages, such as species from the Chytridiomycota and Zygomycota, are capable of VLCPUF A production. It was also found that VLCPUF As are not essential for growth at low temperatures, as Penicillium rugulosum, capable of producing 'fatty acids no longer or more unsaturated than C18:3 n3, demonstrated over 2 g of biomass per 100 ml of broth when grown at 5°C. This indicates that trienoic fatty acids are sufficient for maintaining membrane fluidity, although other factors may play a role in P. rugulosum's low temperature growth. Comparatively, VLCPUFA producing Mortierella species produced 200-250 mg of biomass, whereas the majority of non- VLCPUF A producing isolates produced 106-115 mg of biomass per 100 ml of broth. The total lipid unsaturation indices of nine isolates grown under three temperature regimes showed that the lowest growth temperature, 5°C, produced the highest un saturation index value III SIX of the organisms. 15°C produced the highest unsaturation index value in two of the isolates. This suggests that temperature has an effect on fungal lipid composition, and that lower temperatures may increase lipid unsaturation levels. It was also found that the ~6 elongase, initially identified from Mortierella alpina, is indicative for VLCPUF A producing fungi. The genomic conserved sequence found within ~6 elongases was used to develop primer sets that could be used with a PCR based methodology to screen fungal isolates for VLCPUF A production. The method successfully identified VLCPUF A producing Mortierella and Allomyces species, and was not found to amplify non-Ad elongases. Finally, recombinantPhaffia rhodozyma strains were developed using the ~5 desaturase and ~6 elongase from Mortierella alpina. The fatty acid profiles of the recombinant strains displayed novel fatty acids such as C20:2 n6 and C20:3 n3, and putatively, C18:2 ~5, 9 and C18:3 ~5, 9, 12 which correlated with the inserted genes.

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Khang, Nguyen Thi Kim. "Genetic factors affecting the omega-3 and omega-6 fatty acid variation in egg yolk." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=982352107.

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Kunihiro, Andrew G. "The relationship between dietary omega-3 and omega-6 fatty acid intake and colorectal cancer." Thesis, California State University, Long Beach, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1527970.

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Colorectal cancer (CRC) is the fourth leading cause of cancer-related deaths in the United States and the second most expensive. Low compliance with preventive screening predisposes a large portion of the at-risk population to poorer outcomes. Therefore, identification of primary interventions for those not regularly screened for CRC is of utmost importance. Self-reported dietary ω-3 and ω-6 fatty acid intake were used to determine the cross-sectional relationship with CRC cases (n = 211). Men and women of various ethnic backgrounds (N = 15,178) from the National Health and Nutrition Examination Survey (NHANES), 1999–2010, were eligible for inclusion in this study. Dietary ω-3 intake and the ω-3:ω-6 ratio were negatively associated with CRC while dietary ω-6 intake was positively associated with CRC, for those age 20 to < 50 years, after multivariate adjustment. The Glasgow Prognostic Score was also found to be significantly associated with both dietary ω-3 and ω-6 intake for all age groups.

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Bernard, Jonathan. "Déterminants nutritionnels précoces du neurodéveloppement des enfants de l'étude EDEN : rôle des acides gras polyinsaturés." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00986264.

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Contexte : De la conception à l'âge adulte, de nombreux déterminants environnementaux influencent le neurodéveloppement. Des études montrent que durant la fin de la grossesse et les premiers mois de vie, une grande quantité d'acides gras polyinsaturés (AGPI), notamment à longue chaîne (AGPI-LC), se fixe dans le tissu cérébral. Un apport optimal durant ces périodes critiques pourrait soutenir précocement le bon développement du cerveau et de ses fonctions.Objectifs : Étudier les relations entre les expositions pré- et postnatales précoces aux AGPI, et le neurodéveloppement d'enfants de 2 et 3 ans.Population : Les données utilisées étaient celles de l'étude EDEN, une cohorte mère enfant ayant recruté 2002 femmes enceintes dans les maternités de Nancy et Poitiers entre 2003 et 2006. L'alimentation maternelle pendant la grossesse a été évaluée par un questionnaire de fréquence alimentaire et une table de composition nutritionnelle. Quatre questionnaires postnatals ont permis d'évaluer la durée d'allaitement maternel, et la composition lipidique du colostrum des mères allaitantes a été analysée par chromatographie en phase gazeuse. Des questionnaires parentaux (2 et 3 ans) et un examen neuropsychologique (3 ans) ont permis d'évaluer plusieurs aspects du neurodéveloppement. Les analyses statistiques ont été réalisées par régressions linéaires multivariées, après ajustement sur de nombreux facteurs de confusion potentiels.Résultats : Les scores de neurodéveloppement à 2 et 3 ans des enfants allaités étaient plus élevés que ceux des enfants non allaités. Chez les enfants allaités, la durée d'allaitement maternel était associée positivement au neurodéveloppement. Le rapport n 6/n 3 dans l'alimentation maternelle en acides gras en fin de grossesse était négativement associé à plusieurs mesures du neurodéveloppement, et cette association était renforcée chez les enfants non allaités. La composition du colostrum en AGPI et en AGPI-LC reflétait amplement les apports nutritionnels en AGPI et en AGPI-LC en fin de grossesse. L'utilisation de matières grasses alimentaires était aussi associée à la composition du colostrum. Les différences de neurodéveloppement des enfants allaités ne semblait pas être expliquées par la composition du colostrum en AGPI ni en AGPI-LC, à l'exception de la teneur en acide linoléique qui était négativement associée à certaines mesures du neurodéveloppement. Dans l'ensemble, les associations avec le neurodéveloppement étaient plus fréquemment retrouvées avec les questionnaires parentaux, mais certaines évaluations par les psychologues venaient parfois conforter ces résultats.Conclusion : Associés à ceux de la littérature, ces résultats soulignent le rôle notable des AGPI durant les périodes pré- et postnatale précoce pour le neurodéveloppement de l'enfant. Le suivi des enfants de l'étude EDEN jusqu'à leur 5 ans permettra d'étudier la persistance de ces résultats. Dans une perspective de santé publique, ces travaux rappellent la nécessité de promouvoir l'allaitement maternel dans la durée et de surveiller l'équilibre des apports nutritionnels en AGPI pendant la grossesse et la période de lactation.

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Natacci, Lara Cristiane. "Associação entre consumo de ácidos graxos ômega 3 e transtorno de ansiedade: análise transversal do Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil)." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/5/5169/tde-23102018-101131/.

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oucos estudos avaliaram a associação da ingestão de ácidos graxos ômega 3 e transtornos de ansiedade. O presente estudo utilizou dados transversais do exame de linha de base (2008-2010) do Estudo Longitudinal Brasileiro de Saúde do Adulto - ELSA-Brasil para avaliar essa associação. A exposição dietética foi medida por um questionário quantitativo de frequência alimentar validado para a população brasileira e adaptado para o estudo, e os diagnósticos mentais foram avaliados pelo Clinical Interview Schedule-Revised Version - CIS-R, diagnosticando transtornos mentais de acordo com a Classificação Internacional de Doenças - CID-10. Modelos de regressão logística foram construídos utilizando quintis do consumo de ácidos graxos ômega 3, ácidos graxos ômega 6, razão de consumo n-6/n-3, e ácidos graxos poli-insaturados, usando o primeiro quintil como referência. Dos 15.105 sujeitos participantes do ELSA-Brasil, foram excluídos aqueles que relataram ingestão de menos de 500 ou mais de 4000 kcal, aqueles que relataram ingestão de suplementos n-3 ou n-6 e aqueles que foram submetidos a cirurgia bariátrica. Após as exclusões, 12268 participantes permaneceram na análise, dos quais 1893 (15,4%) apresentaram transtornos de ansiedade. Os indivíduos com transtorno de ansiedade eram mais jovens, de sexo feminino, menor escolaridade e renda, referiram tabagismo atual e atividade física mais leve. Valores mais altos de IMC e de proteína C reativa de alta sensibilidade foram observados nos indivíduos com ansiedade. A ingestão diária média de ácido eicosapentaenoico (EPA), ácido docosapentanoico (DPA) e ácido docosaexaenoico (DHA) foi significativamente menor em participantes com ansiedade. Um maior consumo desses três ácidos graxos da família ômega-3 foi observado em indivíduos com mais idade, maior renda e escolaridade, com dislipidemia, consumo de álcool e tabagismo atuais, e prática de atividade física vigorosa. Após o ajuste para variáveis sociodemográficas (idade, sexo, etnia e educação) fatores de risco cardiovascular (hipertensão, diabetes, dislipidemia, tabagismo, ingestão de álcool e atividade física), calorias totais, qualidade da dieta e depressão, os participantes do quinto quintil de ingestão de EPA, DHA e DPA mostraram associação inversa com transtornos de ansiedade: OR 0,82 (IC 95%, 0,69-0,98), OR 0,83 (IC 95%, 0,69-0,98) e OR 0,82 (IC 95%, 0,69-0,98), respectivamente. Participantes no quinto quintil de razão ômega-6/ômega-3 tiveram associação positiva com transtornos de ansiedade. Nenhuma associação foi encontrada com a ingestão de PUFA, ou ômega-3 e ômega-6 isoladamente com ansiedade após os ajustes. Nesta análise, uma alta ingestão de ômega-3 EPA, DHA e DPA foi inversamente associada com a presença de transtornos de ansiedade, enquanto que a alta razão ômega-6/ômega-3 foi diretamente associada à presença desses transtornos, sugerindo um possível efeito protetor dos ácidos graxos omega-3 EPA, DPA e DHA contra a ansiedade
Few studies have evaluated the association of omega-3 fatty acids intake and anxiety disorders. The present study used cross-sectional data from the baseline (2008-2010) examination of the Brazilian Longitudinal Study of Adult Health - ELSA-Brazil to evaluate this association. The dietary exposure was measured by a quantitative food frequency questionnaire validated for the brazilian population and adapted for the study, and the mental diagnoses were assessed by the Clinical Interview Schedule-Revised Version (CIS-R), diagnosing mental disorders according to the International Classification of Diseases - ICD-10. Logistic regression models were built using quintiles of omega-3 fatty acids, omega-6 fatty acids, omega-6/omega-3 ratio, and polyunsaturated fatty acids consumption, using the first quintile as a reference. Of the 15,105 subjects participating in ELSA-Brazil, those who reported ingestion of less than 500 or more than 4000 kcal, those who reported ingestion of omega-3 or omega-6 supplements and those had undergone bariatric surgery were excluded. After exclusions, 12,268 participants remained in the analysis, of whom 1893 (15.4%) had anxiety disorders. Subjects with anxiety disorder were younger, female, had lower education and income, reported current smoking and mild physical activity. Higher values of BMI and high sensibility C reactive protein were observed in subjects with anxiety. The mean daily intakes of eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) were significantly lower in subjects with anxiety. A higher intake of these three omega-3 fatty acids was observed in older individuals with higher income and education, with current dyslipidemias, alcohol consumption and smoking, and vigorous physical activity. After adjustment for socio-demographic variables (age, sex, ethnicity and education), cardiovascular risk factors (hypertension, diabetes, dyslipidemia, smoking, alcohol intake and physical activity), total calories, diet quality and depression, EPA, DHA and DPA intakes showed an inverse association with anxiety disorders: OR 0.82 (95% CI, 0.69-0.98), OR 0.83 (95% CI, 0.69-0.98) and OR 0.82 (95% CI, 0.69-0.98), respectively. Participants in the fifth quintile of omega-6/omega-3 ratio had a positive association with anxiety disorders. No association was found with ingestion of PUFA, or omega-3 and omega-6 alone with anxiety after adjustments. In this analysis, a high intake of omega-3 EPA, DHA and DPA was inversely associated with the presence of anxiety disorders, while the higher omega-6 omega-3 ratio was directly associated with the presence of these disorders, suggesting a possible protector effect of omega-3 fatty acids EPA, DPA and DHA against anxiety

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Miyake, Juliano Andreoli. "Estudo morfológico e molecular de proteínas envolvidas nos processos de invasão, migração e angiogênese em gliomas tratados com ácido gama-linolênico." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/42/42134/tde-02022010-112311/.

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O glioblastoma multiforme (GBM) é a forma mais maligna de tumor cerebral, originado de células astrocíticas e caracterizado pela intensa proliferação, angiogênese e invasão celular pelo parênquima cerebral normal. O ácido gama-linolênico (GLA) mostrou ter ações anti-tumorais, nos processos de proliferação, migração e angiogênese. Utilizou-se o modelo ortotópico de GBM de rato (C6) e o modelo ex vivo tratados com GLA para análise de migração e proliferação celular. Foi observada uma redução da imunomarcação do fator de crescimento para endotélio vascular (VEGF), seu receptor Flt-1 e da metaloproteinase-2 de matriz, com consequente diminuição de vasos após o tratamento com GLA. No modelo ex vivo observou que o GLA reduziu a distância de migração e a mitose das células tumorais e também causou aumento das células tumorais em processo de apoptose. Os resultados revelaram que o GLA foi capaz de modular a expressão de algumas proteínas envolvidas nos processos angiogênico, migratório e proliferativo do GBM, o que sugere a sua utilização no tratamento desta patologia.
Glioblastoma multiforme (GBM) is the most malignant form of brain tumour originating from astrocytes and is characterized by intense proliferation, angiogenesis and cell invasion through the normal brain parenchyma. Gamma-linolenic acid (GLA) has anti-tumour activities in the processes of proliferation, migration and angiogenesis. This study used the orthotopic GBM rat model (C6) and ex vivo model treated with GLA to analyze cell migration and proliferation. Decreased immunostaining was observed for vascular endothelial growth factor (VEGF), its receptor Flt-1 and matrix metalloproteinase-2, with consequent reduction of blood vessels after treatment with GLA. In the ex vivo model GLA reduced the migration distance and mitosis of tumor cells and increased tumour cell apoptosis. The results revealed that GLA was able to modulate the expression of several proteins involved in angiogenesis, migration and proliferation in GBM, supporting the use of GLA in the treatment of this disease.

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Barbosa, Milena Maria de Araújo Lima. "Adiponectina modifica a resposta à suplementação de ômega-3 em humanos com fatores de risco cardiovascular." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/6/6138/tde-25112015-101332/.

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INTRODUÇÃO: Ácidos graxos ômega-3 (-3) apresentam características cardioprotetoras e seu baixo consumo tem sido associado ao aumento da resistência insulínica e à baixa concentração de adiponectina no sangue. OBJETIVO: Testar se a suplementação com -3 melhora o perfil cardiometabólico em humanos com fator de risco cardiovascular e se a concentração basal de adiponectina modifica a resposta a essa suplementação. MÉTODOS: Neste ensaio clínico, duplo-cego, placebo-controlado e paralelo, distribuímos aleatoriamente 80 indivíduos nos grupos -3 (suplementado com 3,0 g/dia de óleo de peixe, contendo 37 por cento de ácido eicosapentaenoico [EPA] e 23 por cento de ácido docosahexaenoico [DHA]) e placebo (3,0 g/dia de óleo de girassol, contendo 65 por cento de ácido linoleico), ambos suplementados durante dois meses. Avaliamos concentração sérica de adiponectina e leptina, perfil lipídico e de apolipoproteínas, LDL eletronegativa, marcadores inflamatórios (interleucinas 2, 4, 6, 8 e 10, MCP1, IFN- e TNF-) e metabolismo glicídico (glicose e insulina), adotando nível de significância de 5 por cento . RESULTADOS: No momento basal, os grupos -3 e placebo foram semelhantes quanto ao sexo, idade (média de 52,0 anos), raça, estado civil, trabalho, escolaridade e renda. Após intervenção, o grupo -3 aumentou a concentração sérica de adiponectina. No geral, as citocinas apresentaram redução após intervenção em ambos os grupos; IL-10 foi a única cuja concentração média aumentou, no grupo -3, mas, sem diferença significativa entre os grupos. Ao estratificar os indivíduos do grupo -3 segundo concentração basal de adiponectina, aqueles com menores concentrações tiveram maior redução de colesterol total, LDL, LDL/HDL, LDL/Apo B e LDL(-). Indivíduos que apresentaram maior variação da concentração de adiponectina reduziram a glicemia. CONCLUSÕES: A suplementação com -3 melhora o perfil cardiometabólico e aumenta a concentração sérica de adiponectina em indivíduos com fatores de risco cardiovascular. Indivíduos com baixa concentração basal de adiponectina são mais beneficiados pela ingestão desses ácidos graxos.
BACKGROUND: Omega-3 fatty acids (-3) have shown cardioprotective characteristics and their low consumption has been associated with increased insulin resistance and low blood concentration of adiponectin. OBJECTIVE: To analyze if -3 supplementation improves cardiometabolic profile in humans with cardiovascular risk factor and if adiponectin concentration at baseline level modifies the response to this supplementation. METHODS: In this double-blind, placebo-controlled, clinical trial, we randomized 80 subjects into two groups: -3 (supplemented with 3.0g/day of fish oil containing 37 per cent eicosapentaenoic acid [EPA] and 23 per cent docosahexaenoic acid [DHA]) and placebo (3.0g/day of sunflower oil containing 65 per cent linoleic acid). Both groups received supplementation for two months. At baseline period and after eight weeks of intervention, we evaluated serum adiponectin and leptin, lipid profile and apolipoproteins, electronegative LDL, inflammatory markers (interleukin 2, 4, 6, 8 and 10, MCP1, IFN- and TNF-) and glucose metabolism (glucose and insulin). The significance level was set at p <0.05. RESULTS: At baseline period, -3 and placebo groups were similar regarding sex, age (mean age of 52.0 years), race, marital status, occupation, education and income. After supplementation, -3 group presented an increased serum adiponectin. In general, for both -3 and placebo groups, the concentration of cytokines decreased after intervention IL-10 was the only cytokine that increased the concentration; however, -3 group showed similar variations when compared to the placebo group. After -3 group were stratified by adiponectin concentration at baseline, we observed that individuals with lower adiponectin concentration had a higher reduction of total cholesterol, LDL, LDL/HDL, LDL/Apo B and LDL (-). Individuals who had a higher variation of adiponectin concentration presented reduced blood glucose. CONCLUSIONS: -3 supplementation improves cardiometabolic profile and increases serum adiponectin in people with cardiovascular risk factors. Individuals with low basal concentration of adiponectin are more benefited by the intake of these fatty acids.

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Xu, Yi. "Development of a Novel Omega-6 Fatty Acid Based Treatment Strategy for Colon Cancer by Knocking Down Delta-5-Desaturase and Exploiting High COX-2 Levels in Cancer CellsTumors." Diss., North Dakota State University, 2017. http://hdl.handle.net/10365/25947.

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Colon cancer is the third most commonly diagnosed cancer in the world. Research showed that arachidonic acid, a downstream ?-6 fatty acid (?-6), plays a role in colon cancer development by producing deleterious metabolites from its COX-2 catalyzed peroxidation. On the other hand, dihomo-?-linolenic acid (DGLA), the immediate precursor of arachidonic acid, may represent an exceptional ?-6 associated with anti-cancer activities. However, the mechanism of DGLA?s anti-cancer effect still remains unclear, and the rapid conversion of DGLA to arachidonic acid in human body by delta-5 desaturase (D5D) greatly restricts DGLA?s availability. Recent work from Dr. Qian?s group demonstrated that DGLA can undergo a unique pathway during COX-2-catalyzed peroxidation and produce distinct free radical byproducts. Here we proposed that (1) DGLA?s anti-cancer activity is derived from its distinct byproduct, e.g., 8-hydroxyoctanoic acid (8-HOA), from COX-2-catalyzed peroxidation, and (2) by knocking down cellular D5D expression, we can take advantage of the commonly overexpressed COX-2 in cancer cells to promote 8-HOA formation, inhibit colon cancer growth and migration, and develop a novel cancer therapy and a paradigm shift concept in contrast to classic COX-2 inhibition strategy in cancer treatment. Our results showed that 8-HOA, at physiological concentrations, could suppress human colon cancer cell growth and migration, by serving as a histone deacetylase inhibitor and DNA damage agents. Data also showed that knocking down D5D in colon cancer cells promoted endogenous formation of 8-HOA to a threshold level which then inhibited cancer cell growth and migration. Consistent with the in vitro data, knocking down D5D in human colon cancer cell-derived mice xenograft tumors along with DGLA supplementation promoted endogenous formation of 8-HOA in vivo and significantly suppressed tumor growth. In addition, direct supplementation and endogenous formation of 8-HOA from COX-2 catalyzed DGLA peroxidation were found to enhance the efficacies of various chemotherapeutic drugs. In conclusion, we demonstrated that by taking advantage of commonly overexpressed COX-2 in cancer, D5D knockdown can promote the formation of 8-HOA from DGLA peroxidation to inhibit cancer growth and migration. Results from this work will lead us to develop a novel ?-6 based treatment strategy for colon cancer.
NCI/NIH: R15CA140833
National Institutes of Health (NIH)
Sanford Health-NDSU Collaborative Research Seed Grant

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Raposo, Helena Fonseca 1981. "Efeito de acidos graxos n-3 e n-6 sobre a expressão e atividade da proteina de transferencia de colesteril ester (CETP) em camundongos transgenicos." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314300.

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Orientador: Helena Coutinho Franco de Oliveira
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-11T11:46:21Z (GMT). No. of bitstreams: 1 Raposo_HelenaFonseca_M.pdf: 1257741 bytes, checksum: f53550bd6c88a5cd12f0daf241da3486 (MD5) Previous issue date: 2008
Resumo: Os óleos de peixe e de milho são fontes de ácidos graxos poli-insaturados (PUFA) n-3 e n-6, respectivamente. Estes ácidos graxos são ligantes naturais dos receptores ativados por proliferadores de peroxissomos (PPARs) e, dessa forma, modificam a expressão de diversos genes envolvidos no metabolismo de lipídios. A proteína de transferência de colesteril-éster (CETP) é uma proteína plasmática sintetizada em vários tecidos, principalmente do fígado. A CETP participa do transporte reverso de colesterol, reduzindo HDL no plasma e aumentando o risco de aterosclerose. Este trabalho teve como objetivo investigar os efeitos dos óleos ricos em PUFA n-3 e n-6 e de fibratos (ligantes sintéticos de PPAR e agentes redutores de triglicérides) sobre a expressão e atividade da CETP. Assim, camundongos transgênicos que expressam a CETP foram tratados por duas semanas com óleo de peixe, óleo de milho ou salina, e camundongos CETP hipertrigliceridêmicos foram tratados com gemfibrozil (GEM), fenofibrato (FENO), bezafibrato (BEZA) ou veículo (control). Após os tratamentos com os PUFA, não foi verificada diferença no peso corporal, na ingestão ou no peso relativo do fígado e tecidos adiposos. Também não houve alteração das concentrações plasmáticas de glicose e triglicerídios. O óleo de peixe reduziu os níveis de ácidos graxos livres (37%) e colesterol (15%), enquanto o óleo de milho aumentou significativamente os níveis de colesterol. Comparado ao grupo salina, os camundongos tratados com óleo de milho apresentaram aumento nos níveis de leptina (30-40%). O tratamento com óleo de peixe elevou os níveis de adiponectina quando comparados com o grupo salina (27%) e com o grupo tratado com óleo de milho (31%). Dois dos três fibratos testados (FENO, GEM) induziram elevação da atividade plasmática (15-30%) e da expressão hepática de RNAm da CETP (53-75%) quando comparados ao grupo controle. FENO também reduziu a concentração plasmática de triglicérides. O óleo de peixe aumentou os níveis plasmáticos de CETP em relação aos grupos salina e óleo de milho (13-14%), efeito verificado apenas nas fêmeas. Entretanto, não foi observada alteração na expressão hepática de RNAm de CETP. Verificou-se que os tratamentos com os óleos PUFA reduziram a expressão hepática de RNAm de PPAR_ (36%) e o óleo de milho induziu aumento da expressão do fator de transcrição SREBP1 (120%) nos machos, mas não nas fêmeas. Os óleos PUFA também induziram aumento da expressão de SREBP2, porém, apenas em fêmeas. As alterações diferenciais de RNAm de PPAR_, SREBP1 e SREBP2 em cada sexo poderiam estar implicadas na resposta gênero-específica da CETP frente aos PUFA. Assim concluímos que o gene da CETP é responsivo aos agonistas sintéticos de PPAR_, e que os ácidos graxos n-3 controlam a expressão da CETP de maneira gênero-dependente e por mecanismo pós-transcricional
Abstract: Fish and corn oils are n-3 and n-6 polyunsaturated fatty acid (PUFA) sources, respectively. They are natural ligands of the peroxisome proliferator activated receptors (PPARs), thus capable of modifying the expression of several genes involved in lipid metabolism. CETP is a plasma protein synthesized in several tissues, mainly liver, which reduces plasma HDL and increases the risk of atherosclerosis. The aim of this work was to investigate the potential effects of PUFA oils and fibrates on the CETP levels. Therefore, CETP transgenic mice were treated during 2 weeks with fish oil (FO), corn oil (CO) or saline, whilst hypertrygliceridemic CETP mice were treated with gemfibrozil (GEM), fenofibrate (FENO), bezafibrate (BEZA) or vehicle (control). There were no differences in body weight, food intake and relative weight of liver and adipose tissue after PUFA or saline treatments. Also, no changes were verified in glucose and triglyceride plasma levels after both PUFA treatments. FO reduced plasma free fatty acid (37%) and cholesterol (15%) levels, whilst CO increased cholesterol mildly. Compared to saline, mice treated with CO showed an increase in leptin levels (30-40%). Treatment with FO enhanced adiponectin plasma levels when compared to saline (27%) and CO (31%). Two out of the three fibrates (FENO, GEM) induced elevation in plasma CETP activity (15- 30%) and liver mRNA expression (53-75%) when compared to control. FENO also reduced triglyceride levels. FO increased CETP plasma levels (13-14%) when compared to CO and saline, an effect verified only in females. However, no changes were observed in liver CETP mRNA expression. FO treatment decreased PPAR_ (36%) and CO increased SREBP1 liver mRNA levels (120%) in males, but not in females. PUFA treatment increased SREBP2 mRNA only in females. These distinct mRNA changes could explain genderspecific CETP response to PUFA treatments. In conclusion, CETP gene is responsive to PPAR_ agonists, and n-3 PUFA (FO) can regulate CETP expression by post-transcriptional mechanisms, in a manner dependent on the female context
Mestrado
Fisiologia
Mestre em Biologia Funcional e Molecular

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Mouad, Ana Maria. "Biocatálise na produção de moléculas orgânicas: oxidorredutases de fungos marinhos para a síntese de álcoois quirais e lipase de Candida antarctica na produção de amidas fenólicas graxas." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/75/75131/tde-20052014-162233/.

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Neste trabalho, enzimas álcool-desidrogenases provenientes de fungos marinhos e a lipase imobilizada de Candida antarctica foram utilizadas para produção de compostos de interesse sintético e biológico. No capítulo 1, enzimas álcool-desidrogenases de fungos isolados da alga marinha Bostrychia radicans foram empregadas em reações de redução de cetonas fluoradas 1-5. Os fungos identificados como Botryosphaeria sp. CBMAI 1197, Eutypella sp. CBMAI 1196, Hidropisphaera sp. CBMAI 1194 e Xylaria sp. CBMAI 119 atuaram como biocatalisadores nestas reações levando à produção de álcoois com elevada pureza enantiomérica. O fungo Botryosphaeria sp. CBMAI 1197 destacou-se frente aos demais microrganismos, produzindo os álcoois (S)-2,2,2-trifluoro-1-feniletanol (1a) e (R)-1-(2,4,5-trifluorofenil)etanol (3a) com excelentes conversões (100% e 97%) e excessos enantioméricos (ee >99%). Este fungo também apresentou enzimas álcool-desidrogenases ativas frente a cetonas dicarboniladas 4-5, produzindo os álcoois 4,4,4-trifluoro-1-fenil-1,3-butanodiol (4a) e 4,4,4-trifluoro-1-(2-naftalenil)-1,3-butanodiol (5a) com 100% de conversão em ambos os casos e com purezas enantioméricas respectivas a 99% e 97%. Este foi o primeiro estudo realizado no Brasil com fluorocetonas dicarboniladas e com os fungos isolados da alga marinha Bostrychia radicans. No capítulo 2, a lipase comercial de Candida antarctica foi o biocatalisador empregado em reações de aminólise entre os ésteres linoleato de etila (1) e salicilato de etila (3), a amina graxa N-dodecilamina (2) e os aminoálcoois (4-9). A amina graxa N-dodecilamina (2) também foi utilizada em reações com o linoleato de etila (1), onde a lipase de Candida antarctica produziu a respectiva amida graxa 10 com rendimentos superiores a 95%. Os aminoálcoois foram selecionados para reações com o salicilato de etila (3), onde a lipase exibiu quimiosseletividade pelo grupo amino, produzindo predominantemente amidas fenólicas (12-19) com rendimentos entre 23-68%. A enzima CALB apresentou quimiosseletividade reduzida na reação com o 5-aminopentanol (6) onde os produtos amida 14 e éster 15 foram obtidos com rendimentos de 44 e 33%, respectivamente. O produto 2-hidroxi-N-(2-hidroxipropil)benzamida (19) foi obtido com rendimento superior a 90% a partir da reação catalisada pela lipase de Candida antarctica. Este produto foi selecionado como intermediário para a síntese de uma molécula hidrofóbica 21 que apresenta o éster oleato de etila em sua constituição. O produto 21 foi obtido com 75% de rendimento. As amidas fenólicas 12-21 produzidas neste trabalho são derivadas do ácido linoleico (ômega 6) e do ácido salicílico, os quais apresentam propriedades emolientes e antioxidantes. Estes compostos são interessantes para a formulação de produtos cosméticos de aplicação cutânea. Neste processo biotecnológico as reações foram conduzidas na ausência de solventes orgânicos, evitando o tratamento de solventes voláteis e a formação de subprodutos. Os compostos foram analisados por Cromatografia líquida de alta eficiência e caracterizados por RMN (1H, 13C), EMAR e IV. A aplicação de reações de biocatálise seja através de células microbianas ou de enzimas isoladas foram muito promissoras na síntese de compostos orgânicos de interesse como álcoois enantiomericamente puros ou amidas graxas.
In this work, alcohol dehydrogenase (ADHs) enzymes from marine fungi and immobilized lipase from Candida antarctica were employed for the production of compounds of biological and synthetic interest. In chapter 1, ADHs of fungi isolated from the marine alga Bostrychia radicans were used in reduction reactions of fluorinated ketones 1-5. The fungi identified as Botryosphaeria sp. CBMAI 1197, Eutypella sp. CBMAI 1196, Hidropisphaera sp. CBMAI 1194 and Xylaria sp. CBMAI 119 acted as biocatalysts in these reactions leading to production of alcohols with high enantiomeric purity. The fungus Botryosphaeria sp. CBMAI 1197 presented highlighted compared to other microorganisms producing the alcohols (S)-2,2,2-trifluoro-1-phenylethanol (1a) and (R) -1 - (2,4,5-trifluorophenyl) ethanol (3a) with excellent conversions (100% and 97%) and enantiomeric excesses (ee > 99%). This fungus also exhibited ADHs enzymes active with dicarbonylateds ketones, leading to the production of the alcohols 4,4,4-trifluoro-1-phenylbutane-1,3-diol (4a) and 4,4,4-trifluoro-1-(naphthalen-2-yl)butane-1,3-diol -1,3-butanediol (5a) with conversions of 100% in both cases and enantiomeric excess of 99%-97%, respectively. This was the first study conducted with dicarbonilated fluoroketones 4-5 and with fungi isolated from the marine alga Bostrychia radicans in Brazil. In chapter 2, immobilized lipase from Candida antarctica was used as biocatalyst in the aminolysis reaction between esters of ethyl linoleate (1) and ethyl salicylate (3), the fatty amine N-dodecylamine (2) and the aminoalcohols (4-8). Six aminoalcohols were selected for reactions with ethyl salicylate (3), where the lipase exhibited chemoselectivity by the amino groups, producing predominantly phenolic amides in yields of 23-63%. The CALB exhibited um reduction in chemoselectivity in the reaction with 5-aminopentanol (6) where the amide 14 and ester 15 products were obtained with 44% and 33% yields. The product 2-hydroxy-N-(2-hydroxypropyl) benzamide (19) was obtained in yield greater than 90% from the reaction catalyzed by lipase from Candida antarctica. This product was selected as reagente for the synthesis of a hydrophobic molecule 21 presenting ester ethyl oleate in its constitution. The product 21 was obtained in 75% yield. The phenolic amides 12-21 produced in this work are derived from linoleic acid (omega 6) and salicylic acid, which presents emollient and antioxidants properties. These compounds are interesting for the formulation of cosmetic products for skin application. In this biotechnological process, the reactions were carried out under solvent-free conditions and vacum, avoiding the treatment of volatile solvents and by-product formation. The compounds were analyzed by high performance liquid chromatography and characterized by NMR (1H, 13C), IR and HRMS. Applying biocatalysis reactions, either through microbial cells or isolated enzymes were promising for the synthesis of organic compounds such as enantiomerically pure alcohols and fatty phenolic amides.

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Oliveira, Julicristie Machado de. "Efeito dos ácidos graxos ômega-3 de origem marinha em parâmetros bioquímicos, antropométricos e inflamatórios de adultos que vivem com HIV em terapia antirretroviral: revisão da literatura e ensaio clínico." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/6/6138/tde-27052011-105941/.

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Introdução: A terapia antirretroviral (ART) mudou o curso da Aids, porém está associada a alterações metabólicas e aumento do risco de doenças cardiovasculares. Objetivo: Avaliar o efeito da suplementação com ácidos graxos ômega-3 de origem marinha no perfil lipídico, na homeostase da glicose, na distribuição de gordura corporal e nos marcadores inflamatórios de adultos com HIV em ART. Métodos: Artigo 1. Trata-se de uma revisão sistemática da literatura com metanálise. Realizou-se busca por ensaios clínicos na base de dados PubMed; 33 artigos foram localizados, seis cumpriram os critérios de inclusão e quatro apresentavam qualidade metodológica adequada. Foi realizada metanálise com efeitos fixos e descrição das diferenças de médias sumárias (DMS (IC95 por cento )). Artigos 2 e 3. Trata-se de um ensaio clínico aleatorizado e controlado. Foram recrutados 120 adultos com idade entre 19 e 64 anos, de ambos os sexos. Os indivíduos alocados no grupo intervenção foram suplementados por 24 semanas com 3g de óleo de peixe/dia (900mg de ácidos graxos ômega-3) e indivíduos alocados no grupo controle receberam placebo (óleo de soja). Resultados: Artigo 1. Após 8-16 semanas de intervenção com 900-3360mg de ácidos graxos ômega-3/dia, observou-se redução de -80,34mg/dL (IC 95 por cento : -129,08 a -31,60) nas concentrações de triglicérides. A análise agregada de estudos com média de concentração de triglicérides > 300mg/dL no baseline e intervenção com 1800-2900mg de ácidos graxos ômega-3/dia resultou em redução de -129,72mg/dL (IC95 por cento : -206,54 a -52,91). Artigos 2 e 3. Foram considerados nas análises dados de 83 sujeitos. Os modelos multinível não revelaram relação estatisticamente significante entre a suplementação com óleo de peixe e as mudanças longitudinais nas concentrações de triglicérides (p=0,335), LDL-C (p= 0,078), HDL-C (p=0,383), colesterol total (p=0,072), apo B (p=0,522), apo A1 (p=0,420), razão LDL-C/apo B (p=0,107), índice homa-2 IR (p=0,387), IMC (p=0,068), circunferência da cintura (p=0,128), relação cintura/quadril (p=0,359), PCR ultra sensível (p=0,918), fibrinogênio (p=0,148), e fator VIII (p=0,073). Conclusões: Artigo 1. Diferentes doses de ácidos graxos ômega-3 reduziram modo significativo as concentrações de triglicérides, confirmando a potencial aplicabilidade desse nutriente no tratamento da hipertrigliceridemia em pessoas que vivem com HIV em ART. Artigos 2 e 3. Uma dose relativamente baixa de óleo de peixe para pessoas que vivem com HIV em ART não alterou o perfil lipídico, a homeostase da glicose, a distribuição de gordura corporal e a concentração de marcadores inflamatórios. Recomenda-se, em estudos subseqüentes, a avaliação do efeito de doses mais elevadas, bem como a determinação de marcadores inflamatórios mais sensíveis
Background: Although the antiretroviral therapy (ART) revolutionized the care of HIV-infected subjects, it has been associated with metabolic abnormalities and increased risk of cardiovascular diseases. Aims: To review the effects of marine omega-3 fatty acids on lipid profile, insulin resistance and inflammatory markers in subjects living with HIV on ART. Methods: Paper 1. Thirty three articles were found in a PubMed search; six met the inclusion criteria; and four of them were considered of adequate quality and included. Meta-analysis with fixed effects was performed and weighted mean differences (WMD (95 per cent CI)) were described. Paper 2 and 3. The study was conducted in an HIV/Aids care centre affiliated to the Medical School, University of Sao Paulo. This was a randomized controlled trial that assessed the effects of 3g fish oil/day (900mg of omega-3 fatty acids) or 3g soy oil/day (placebo). A hundred and twenty subjects aged between 19 and 64 years were recruited. The statistical analyses were performed in Stata 9. Results: Paper 1. Data from 83 subjects were included in the analyses. The overall reduction on triglyceride concentrations after 8-16 weeks of treatment with 900-3360mg of omega-3/day was WMD=-80.34mg/dL (95 per cent CI: -129.08 to -31.60). The pooled result of studies with mean triglyceride > 300 mg/dL at baseline and 1800-2900mg omega-3/day was WMD=-129.72mg (95 per cent CI: -206.54 to -52.91). Paper 2 and 3. Multilevel analyses revealed no statistically significant relationships between fish oil supplementation and the longitudinal changes in triglyceride (p= 0.335), LDL-C (p= 0.078), HDL-C (p= 0.383), total cholesterol (p=0.072), apo B (p= 0.522), apo A1 (p=0.420), LDL-C/apo B ratio (p=0.107), homa-2 IR index (p=0.387), BMI (p=0.068), waist circumference (p=0.128), waist/hip ratio (p=0.359), hs-CRP (p=0.918), fibrinogen (p=0.148), and VIII factor (p=0.073). Conclusions: Paper 1. Different doses of omega-3 fatty acids reduced significantly triglyceride concentrations confirming the potential applicability of this nutrient on the management of hypertriglyceridemia in HIV-infected subjects on ART. Paper 2 and 3. A relatively low dose of fish oil for HIV subjects on ART did not change lipid profile, insulin resistance, body fat distribution, and inflammatory markers. Further investigations should considerer the assessment of higher doses and more sensitivity inflammatory markers

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Mahamat, Saleh Yahya. "Etude des associations entre facteurs nutritionnels et risque de cancers cutanés dans les cohortes E3N et EPIC Citrus Intake and Risk of Skin Cancer in the European Prospective Investigation into Cancer and Nutrition Cohort Patterns of Omega-3 and Omega-6 Fatty Acid Dietary Intake and Melanoma Thickness at Diagnosis Circulating 25-Hydroxyvitamin D Level, Vitamin D Intake, and Risk of Skin Cancers: A Systematic Review and Dose-Response Meta-Analysis of Prospective Studies Mediterranean Dietary Pattern and Skin Cancer Risk: A Prospective Cohort Study in French Women. Am JClin Nutr Antioxidant Supplement Use and Risk of Keratinocytes Cancers: A Prospective Cohort Study Baseline and Lifetime Alcohol Consumption and Risk of Skin Cancer in the European Prospective Investigation into Cancer and nutrition cohort (EPIC)." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASR008.

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Titre : Etude des associations entre facteurs nutritionnels et risque de cancers cutanés dans les cohortes E3N et EPICLes cancers cutanés sont les néoplasmes les plus fréquents chez les populations de type Caucasien et leur incidence est en constante augmentation. L'exposition aux rayonnements ultraviolets (UV) est le seul facteur environnemental reconnu comme cause avérée de cancer de la peau et actuellement le seul pour lequel une prévention est possible. Cependant, il apparait de plus en plus probable que certains facteurs nutritionnels, notamment les antioxydants, pourraient empêcher les effets néfastes de l'exposition aux UV et ainsi potentiellement représenter des agents de chimio-prévention des cancers cutanés. Il a également été suggéré que certains groupes d'aliments, tels que les agrumes, les compléments alimentaires, les acides gras, la vitamine D et l'alcool pouvaient être associés à un risque accru de cancers cutanés. Cependant, les études menées jusqu'à présent n'ont pas permis d'émettre de conclusion claire : peu d'études prospectives avec un échantillon suffisamment important et disposant de données sur l'exposition solaire sont disponibles. Il est donc nécessaire de faire progresser nos connaissances dans ce domaine afin de mieux cibler les campagnes de prévention des cancers cutanés.L’objectif principal de cette thèse était d’explorer les relations entre les facteurs nutritionnels et le risque de cancers cutanés. Les données utilisées dans ce projet incluent les données de la cohorte E3N, incluant près de 100 000 femmes françaises suivies depuis 1990, les données de la cohorte EPIC, incluant près de 520 000 participants issus de 10 pays européens, et les données du PMP, une étude prospective incluant 700 patients australiens atteints de mélanome suivis depuis 2014. De plus, les données de la littérature sur les liens entre vitamine D et mélanome ont été résumées et poolées dans une revue systématique et une méta-analyse.Nos résultats suggèrent que l’adhérence au régime méditerranéen est associée à risque plus faible de cancers cutanés, plus particulièrement de mélanome et de carcinome baso-cellulaire ; en revanche la prise de compléments alimentaires en bêta-carotène, vitamine A ou E était associée à un risque accru de carcinomes cutanés. De plus, nous avons observé que les consommations d’agrumes ou d’alcool étaient associées à un risque plus élevé de cancers cutanés. Par ailleurs, nos résultats suggèrent qu’une forte consommation d’un régime « riche en viande, poisson et graisses » est associée à l’épaisseur du mélanome. Enfin, les résultats de notre méta-analyse suggèrent que les taux circulants élevés de vitamine D sont associés à un risque accru de mélanome et de carcinomes cutanés.Les travaux de cette thèse ont mis en lumière des relations complexes entre les facteurs nutritionnels et le risque de cancers cutanés. Par ailleurs, ils soulèvent plusieurs questions qu’il serait envisageable d’approfondir dans d’autres études. Si ces résultats sont répliqués, ils pourraient, à terme, avoir un impact sur les stratégies de prévention des cancers cutanés.Mots-clés : cancers cutanés ; régime méditerranéen ; compléments en antioxydants ; agrumes ; alcool ; profils alimentaires ; vitamine D ; cohorte prospective ; méta-analyse
Title: Associations between nutritional factors and skin cancer risk in the E3N and EPIC cohortsSkin cancers are the most frequent neoplasms in Caucasian populations and their incidence has been constantly rising. Ultraviolet (UV) radiation exposure is the only environmental risk factor recognized as a cause of skin cancer and the only factor for which prevention is possible. However, it appears increasingly likely that several nutritional factors, particularly antioxidants, could counteract the negative effects of UV exposure and thus potentially represent chemo-preventive agents for skin cancer. It has also been suggested that several food groups, such as citrus, dietary supplements, vitamin D, fatty acids, and alcohol, could be associated with skin cancer risk. However, investigations to date did not allow to draw clear conclusions; few prospective data are indeed available within a sufficiently large sample and available sun exposure data. It is thus crucial to advance our knowledge in this field in order to target skin cancer prevention campaigns more precisely.The objective of this doctoral project was to study the relationships between nutritional factors and skin cancer risk. To achieve our objective, we used data from E3N, a prospective cohort of ~ 100,000 French women followed since 1990, data from EPIC cohort, a prospective cohort involving ~520,000 participants who have been followed-up in 23 centers from 10 European countries, and data from PMP, a prospective study of ~700 melanoma patients diagnosed in Queensland between 2010 and 2014. Additionally, data from the literature were summarized and pooled in a systematic review and meta-analysis.Our results suggest that adherence to the Mediterranean diet is associated with a lower skin cancer risk in women, particularly melanoma and basal-cell carcinoma. Intake of supplements in beta-carotene, vitamin A or E was associated with an increased keratinocyte cancer risk in women. In addition, we found positive linear relationships between citrus intake and skin cancer risk, which were mostly driven by associations with keratinocyte cancers, and between alcohol consumption and overall skin cancer risk. However, our results also suggest that people with high meat, fish, and fat intakes, who thus consumed relatively high levels of omega-3 and high omega-6 fatty acid intakes, are more likely to be diagnosed with thick than thin melanomas. In the meta-analysis, we found positive associations between serum 25(OH)D levels and melanoma and keratinocyte cancer risk.This project highlighted complex relationships between nutritional factors and the risk of skin cancers. It also raised several questions that could be considered for further study. If replicated and confirmed in future research, these findings may ultimately have important implications in skin cancer prevention.Keyword: skin cancer ; Mediterranean diet ; antioxidant supplements ; citrus ; alcohol ; dietary pattern; vitamin D; prospective cohort; meta-analysis

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Gonzalez, Dulmelis. "Effect of dietary fatty acids, time of feeding and immune response in poultry /." 2008. http://hdl.handle.net/1957/10225.

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Shin, Dae Keun. "Effect of Conjugated Linoleic Acid or Oleic Acid Addition on Fatty Acid Composition Profiles of Poultry Meat." Thesis, 2010. http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7698.

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Two different studies were conducted to reduce the overall amount of omega-6 fatty acids in broiler chickens. The first experiment was performed to determine the effects of dietary conjugated linoleic acid (CLA) and omega-3 fatty acid combination on the omega-6 fatty acid accumulation in broiler chicken breast and thigh meat. Eight broilers from each treatment were processed at 4 and 6 weeks of age, respectively. Regarding the diets containing five different fat sources, broiler chickens fed CLA and fish oil diet had a lower C20:4 (arachidonic acid, AA, n-6) deposition but showed a higher n-3/n-6 ratio in breast and thigh meat than those fed a flaxseed oil diet and CLA and flaxseed oil diet (P < 0.05). The C20:4 and n-3/n-6 ratio of breast and thigh samples from fish oil diet was similar to those of the conjugated linoleic acid and fish oil combination diet (P > 0.05). However, the addition of CLA and fish oil to the diet resulted in a increase of polyunsaturated fatty acid (PUFA) concentration in broiler chicken breast and thigh meat when compared to that of fish oil diet (P<0.05). The second experiment was conducted based on six different combination of n-3 and n-9 fatty acids. One bird per pen was processed, and each bird was weighed, and blood, liver, breast and thigh samples from the bird were collected. Although the generation of prostaglandin E2 (PGE2) was not affected due to combination of n-3 and n-9 fatty acids in our diets, the deposition of n-6 fatty acids including C18:2 and C20:4 was decreased in broiler chicken breast and/or thigh muscles as n-3 fatty acids were supplied to broiler chickens for 9 weeks. Eicosapentaenoic acid (C20:5, EPA, n-3) addition to poultry diet (FEO) did not reduce the deposition of C18:2 and/or C20:4 as much as C22:6 (FDO) did. When C20:5 and C22:6 were blended to poultry diet (FHO) and fed to broiler chickens for 9 weeks, synergistic effects were observed. Reduction of C20:4 was obtained when FHO diet was fed to broiler chickens, and it may be induced due to decreased expression of delta-6 desaturase mRNA.

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Maurício, Tatiana Sofia Cardoso. "Molecular mechanisms of macrophages adaptation when supplemented with phospholipids with Omega-3 and Omega-6 fatty acids." Master's thesis, 2021. http://hdl.handle.net/10773/32801.

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Macrophages are fundamental cells of the innate immune system, deeply involved in the immune response. These immune cells can express different phenotypes, with a key role in inflammation. The impact of polyunsaturated fatty acids (PUFAs) in the immune system has been extensively investigated in the last decades, particularly the effect of omega-3 (ω-3) and omega-6 (ω-6) fatty acids, in human health. Several studies have demonstrated that polyunsaturated fatty acids are intimately involved in the immune response, attributing an immunomodulatory effect to these substances. The present work provides a multi-omic analysis combining the analysis of the lipidome, the proteome and the metabolome of a macrophage cell line (RAW 264.7). In our study, we employed a liquid chromatography mass-spectrometry based approach (LC-MS), to identify and quantify the changes in the set of lipids, proteins and metabolites, in macrophages supplemented with two types of phospholipids containing omega-3 (PC 18:0/22:6) or omega-6 (PC 18:0/20:4) fatty acids, alone and in the presence of a pro-inflammatory agent, lypopolissacharide (LPS). In the lipidomic analysis, we identified and quantified 299 lipid species. Supplementation of macrophages with ω-3 and ω-6 phospholipids plus LPS, produced significant changes in the lipidome, with a marked increase in lipid species linked to the inflammatory response, enrolled in several pro-inflammatory signalling pathways. In the lipidomic analysis, these compounds also demonstrated a pro-resolving effect of inflammation. Regarding proteomic analysis, resulted in the identification of approximately 3000 proteins, with ω-3 and ω-6 phospholipids reprogramming the proteome of macrophages and amplifying the immune response, by these cells, also promoting the expression of anti-inflammatory proteins. Finally, metabolomic analysis consisted in the identification of 103 metabolites, supplementation with both ω-3 and ω-6 phospholipid induced the expression of several metabolites with a pronounced anti-inflammatory effect. Overall, our data shows that supplementation of macrophages with omega-3 and omega-6 phospholipids, effectively modulates the lipidome, the proteome and the metabolome of these immune cells, affecting several metabolic pathways involved in the immune response, triggered by inflammation. The compounds in study, promoted an increase in the metabolism of macrophages, impairing the pro-inflammatory response in these cells. The results obtained by the 3 omic approaches were congruent, demonstrating the complex metabolic network underlying the activation of macrophages and the role of supplementation with phospholipids.
Os macrófagos são células fundamentais do sistema imune inato, intrinsecamente envolvidas na resposta imune. Estas células imunes podem expressar diferentes fenótipos, com um papel chave nos processos inflamatórios. O impacto dos ácidos gordos poliinsaturados (PUFAs) no sistema imunitário, tem sido extensivamente estudado nas últimas décadas, em particular o efeito dos ácidos gordos ómega-3 (ω-3) e ómega-6 (ω-6), na saúde humana. Vários estudos já demonstraram que os ácidos gordos poliinsaturados participam ativamente na resposta imune, atribuindo um efeito imunomodulatório a estes compostos. O presente trabalho, proporciona uma análise conjunta de ómicas, que combina a análise do lipidoma, do proteoma e do metaboloma de uma linha celular de macrófagos (RAW 264.7). Neste estudo, aplicámos uma metodologia baseada na análise por cromatografia líquida acoplada a espetrometria de massa (LCMS), de modo a identificar e quantificar as alterações ao nível do conjunto de lípidos, proteínas e metabolitos, em macrófagos em resposta à suplementação com dois tipos de fosfolípidos, contendo ácidos gordos ómega-3 (PC 18:0/22:6) ou ómega-6 (PC 18:0/20:4), exclusivamente ou na presença de um agente pró-inflamatório, lipopolissacarídeo (LPS). Na análise lipidómica, identificámos 299 espécies lipídicas. A adição de fosfolípidos ómega-3 e ómega-6 com LPS, produziu alterações significativas no lipidoma das células, com um aumento da abundância relativa de espécies lipídicas associadas à resposta inflamatória, uma vez envolvidas em diversas vias metabólicas de caráter pró-inflamatório. Ao nível do lipidoma, estes compostos demonstraram ainda poder desempenhar um efeito pró-resolvente da inflamação. Relativamente à análise proteómica, esta permitiu identificar aproximadamente 3000 proteínas, tendo os fosfolípidos ómega-3 e ómega-6 induzido remodelação no proteoma dos macrófagos e aumentado a dimensão da resposta inflamatória, por parte destas células, igualmente promovendo a expressão de proteínas de caráter anti-inflamatório. Por fim, a análise metabolómica consistiu na identificação de 103 metabolitos, a adição de fosfolípidos ómega-3 e ómega-6 induziu a expressão de diversos metabolitos com uma notória ação antiinflamatória. De um modo geral, os nosso resultados demonstram que a suplementação de macrófagos com fosfolípidos ómega-3 e ómega-6, vão efetivamente modular o lipidoma, o proteoma e o metaboloma destas células imunes, afetando diversas vias metabólicas envolvidas na resposta imune, desencadeada pela inflamação. Os compostos em estudo promoveram um aumento do metabolismo em macrófagos, enfraquecendo a resposta pró-inflamatória nestas células. Os resultados obtidos pelas 3 análises ómicas são congruentes, demonstrando a complexa rede metabólica subjacente à ativação de macrófagos e o papel da suplementação com fosfolípidos.
Mestrado em Bioquímica

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Senanayake, S. P. J. Namal. "Enzyme-assisted synthesis of structured lipids containing long-chain omega-3 and omega-6 polyunsaturated fatty acids /." 2000.

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Dissertations / Theses on the topic 'Fatty Acids, Omega-6'

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