Dissertations / Theses: 'Fatty acids in human nutrition'

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Crowe, Francesca Lee, and n/a. "A biomarker survey of the fatty acid status of New Zealanders." University of Otago. Department of Human Nutrition, 2006. http://adt.otago.ac.nz./public/adt-NZDU20070328.162638.

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My thesis research has examined the fatty acid composition of serum triacylglycerol, phospholipid and cholesterol ester in 2793 participants who took part in the 1997 National Nutrition Survey - a national population-based survey of New Zealand adolescents and adults aged or [greater than or equal to]̲15 y. Differences in serum fatty acids by sex, age, ethnicity, body mass index and smoking - independent of dietary fat intake - were determined. Serum fatty acids were used as biomarkers of saturated and polyunsaturated fat intake to predict population serum total cholesterol concentrations. The association between n-3 long-chain polyunsaturated fatty acids in serum phospholipid and mental and physical wellbeing, as assessed by the short form-36, was determined. Serum fatty acids have been used as biological markers of fat intake and to predict the risk of disease. The fatty acid composition of serum triacylglycerol, phospholipid and cholesterol ester is subject to alteration by dietary fat but overall, is largely controlled by metabolic enzymes. Non-dietary variables - sex, age, body mass index or cigarette smoking - may influence the activity of these enzymes, which will subsequently alter the fatty acid composition but the extent to which these affect serum fatty acid composition in the general population is poorly understood. Our results showed that the proportion of docosahexaenoic acid in serum phospholipid and cholesterol ester was significantly greater in women by 0.15 and 0.02 mol%, respectively in comparison to men whereas, the proportion of eicosapentaenoic acid was significantly greater in men by 0.08 and 0.1 mol%, respectively, after adjusting for age, ethnicity, body mass index and smoking. A number of differences in the proportion of palmitoleic acid in serum triacylglycerol, phospholipid and cholesterol ester were detected; palmitoleic acid increased across the age categories in women (15-24, 25-44, 45-64 65+ y), was higher in women compared to men, New Zealand Europeans compared to New Zealand Maori and Pacific People, those with a body mass index or [greater than or equal to] 30 kg/m� compared to those with a body mass index < 25 kg/m� and in current smokers in comparison to non-smokers. In women, there was an inverse trend in the proportion of linoleic acid in serum phospholipid and cholesterol ester across the age categories. The proportion of linoleic acid in serum triacylglycerol, phospholipid and cholesterol ester was lower in smokers by 2.19, 1.04 and 0.75 mol%, respectively in comparison to non-smokers. None of these differences could be explained by a difference in dietary fat intake. Consequently, sex appears to affect the metabolism of n-3 long-chain polyunsaturated fatty acids independent of dietary fat intake and metabolic differences associated with age, body mass index and smoking may be at play for a number of other serum fatty acids notably, palmitoleic and linoleic acids. Evidence for a role of dietary fat as a predictor of serum cholesterol concentrations in the general population is conflicting. On one hand, results from cholesterol-lowering dietary intervention trials show unequivocally that decreasing saturated fat intake produces a meaningful reduction in serum cholesterol concentrations. On the other hand, the results of large observational studies show little association between saturated fat intake and cholesterol concentrations. The lack of association in the latter studies may result from errors in dietary assessment and therefore, using serum fatty acids as biomarkers of fat intake may overcome the limitations associated with typical dietary assessment techniques. Participants were divided into quintiles of increasing proportion of serum fatty acids. Each one SD increase in the myristic acid composition of serum cholesterol ester, triacylglycerol and phospholipid was associated with an increase in cholesterol of 0.19, 0.10 and 0.13 mmol/L, respectively after adjusting for confounding variables. The difference in cholesterol concentrations between those categorised into the highest and lowest quintiles of serum cholesterol ester myristate was 0.48 mmol/L. A one SD increase in the linoleic acid composition of serum cholesterol ester, triacylglycerol and phospholipid corresponded to a decrease in cholesterol of 0.07, 0.05 and 0.07 mmol/L, respectively. The difference in cholesterol concentrations between the 1st and 5th quintiles of serum cholesterol linoleate was 0.18 mmol/L. Intake of saturated and polyunsaturated fats, as measured using serum fatty acids, are important determinants of cholesterol concentrations in New Zealanders. It has been hypothesised that a lower intake of n-3 long-chain polyunsaturated fatty acids, largely of marine origin, is implicated in the aetiology of depressive disorder. Results from the majority of observational studies have shown that depressed participants have a lower proportion of eicosapentaenoic or docosahexaenoic acid in phospholipids compared to controls but evidence for an improvement in depressive symptoms after supplementation with n-3 long-chain polyunsaturated fatty acids is conflicting. There is little known about the role that n-3 long-chain polyunsaturated fatty acids may have as predictors of mental wellbeing in the general population. Participants were categorised into quintiles of increasing n-3 long-chain polyunsaturated fatty acids in serum phospholipid. There was no significant trend in self-reported mental wellbeing - the mental component score - across the quintiles of eicosapentaenoic, docosapentaenoic and docosahexaenoic acids or the sum of these three fatty acids after adjusting for confounding variables. There was a significant trend in the mental component score across the quintiles of the ratio of eicosapentaenoic/arachidonic acid; the difference between the highest and the lowest quintile was 6.6 points. There were significant positive trends in self-reported physical health - the physical component score - across the quintiles of eicosapentaenoic and docosapentaenoic acids as well as the ratio of eicosapentaenoic/arachidonic acid ratio; the difference between the 1st and 5th quintiles were 8.6, 6.0 and 8.9 points, respectively. Overall, there appears to be little association between the n-3 long-chain polyunsaturated fatty acid composition of serum phospholipid and self-reported mental health in a population of low fish consumers; however, the proportion of n-3 long-chain polyunsaturated fatty acids may be an important predictor of physical wellbeing in New Zealanders.

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Hynes, Geoffrey Ronald. "Effects of dietary fatty acid composition and energy restriction on adipose tissue obese mRNA, fatty acid composition and serum leptin levels." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29442.

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Dietary fatty acid (FA) composition and energy restriction (ER) independently affect serum leptin levels; however it is not known whether this correlates with changes in obese (ob) gene expression. Herein, we assessed whether dietary FA composition and ER influence white adipose tissue (WAT) ob mRNA by Northern analysis. Animals consumed diets containing tallow (BT), safflower oil (SO) or fish oil (FO) ad libitum or at 60% ad libitum intakes. Serum leptin values were not different between levels of energy intake. ER decreased weight gain and WAT weights, which positively correlated with serum leptin values. WAT ob mRNA levels were in the rank order: FO > SO > BT in depots of all groups with ER showing a lower level of ob mRNA. Data show similarity in ob mRNA levels between depots with discordance in circulating leptin levels. These data suggest that energy restriction exerts greater control over leptin production than dietary fat source.

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Mavrommatis, Ioannis. "The effects of dietary long chain n-3 polyunsaturated fatty acids on soluble epoxide hydrolase and related markers of cardiovascular health." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=56261.

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葉翠宜 and Chui-yee Yap. "Production of docosahexaenoic acid by thraustochytrium SP. under heterotrophic conditions of growth." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31227004.

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Yap, Chui-yee. "Production of docosahexaenoic acid by thraustochytrium SP. under heterotrophic conditions of growth /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B24533324.

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Bulcao, Candice. "Polyunsaturated fatty acid metabolism and effects on colon cancer cell biology in vitro." Thesis, Rhodes University, 2013. http://hdl.handle.net/10962/d1016128.

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Colon cancer is a leading cause of cancer related deaths worldwide. Lifestyle factors such as diet and exercise have been implicated as important agents in colon cancer development and progression. Epidemiological, in vivo and in vitro studies have found that n-3 polyunsaturated fatty acids (PUFAs) reduce colon carcinoma. The role of n-6 PUFAs remains a controversial topic, with studies indicating both promoting and preventing capabilities published. In order to better understand the effects of PUFAs on colon carcinoma, it is important to have an understanding of how they will be broken down in the body. During this study, in silico metabolism of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and arachidonic acid (AA) predicted the formation of hydroxy-, di-hydroxy- and epoxy-FAs. A gas chromatography-mass spectrometry method was developed and validated for the detection of these PUFAs and their cytochrome P450 (CYP) metabolites. A human liver microsomal system for the in vitro metabolism of EPA, DHA and AA was optimised in terms of microsomal and PUFA concentration. The system resulted in the metabolism of the positive control, lauric acid, to 12-hydroxy-lauric acid but was unable to metabolise the PUFAs of interest. EPA, DHA and AA reduced cell viability in the colon carcinoma cell lines SW480 and SW620 in the micromolar concentration range (25 – 200 μM). The CYP epoxidation metabolite of EPA, 17, 18-epoxyeicosatetraenoic acid (17, 18-EpETE) resulted in a significant reduction in SW480 cell viability relative to the parent compound at lower concentrations (25 and 50 μM). Annexin V apoptosis analysis revealed that EPA and 17, 18- EpETE did not result in apoptosis in SW480 cells at a concentration of 25 μM and over an incubation period of 24 hours. A significant reduction in reactive oxygen species production was seen in SW480 cells after incubation with 25 μM 17, 18-EpETE for 24 hours. EPA and 17, 18-EpETE were implicated in the reduction of colon cancer metastasis since they were able to reduce SW480 migration and anchorage independent cell growth. These results indicate that the dietary intake of EPA, DHA and AA may be beneficial to one’s health due to the negative effects that these PUFAs had on colon carcinoma. Future studies are needed to confirm these benefits and compare the effects of the PUFAs to their CYP-metabolites.

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Cuthbertson, Abla Zehour. "Effect of animal type or treatment on the efficiency of lean meat production and the fatty acid composition of meat : thesis submitted for the degree of Master of Agricultural Science." Title page, summary and contents only, 1988. http://web4.library.adelaide.edu.au/theses/09A/09ac988.pdf.

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Includes bibliographical references (leaves 196-220) Studies the growth, body composition, feed intake of grazing animals, the use of anabolic agents, fatty acid composition of ruminants fats; and, the effect of saturated fat on human health.

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Theunissen, Reza. "An investigation of short-chain fatty acid profiles and influential gastrointenstinal microbiota associated with irritable bowel syndrome." Thesis, Nelson Mandela Metropolitan University, 2013. http://hdl.handle.net/10948/d1020943.

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Microbiota are present in large numbers and as a diverse population within the gastrointestinal tract. There are approximately 400 different species of microbiota which may be beneficial, harmful or both, but each play an important role in the regulation and modulation of the hosts’ bowel processes (McOrist et al. 2008; Dethlefsen et al. 2008). Many of these colon microbiota allow for saccharolytic fermentation of non-digestible dietary fibres and carbohydrates into by-products and intermediates, followed by a subsequent conversion into short chain fatty acids (SCFAs) (mainly n-butyric acid, propionic acid and acetic acid) each of which play an important role in maintaining colon homeostasis (Topping & Clifton 2001). A balance of ‘good’ microbiota (e.g., Bacteroides spp./ Bifidobacteria spp.) and ‘bad’ microbiota (e.g., Veilonellae) and the optimal production of various SCFAs within the gut could possibly allow for proper functioning of the large intestine and assist in decreasing the onset of various colonic disorders such as Irritable Bowel Syndrome (IBS). The sample group for the study consists of male and female patients, with an average age of 40 to 50 years old, whom of which have been diagnosed with either constipation IBS (C-IBS) or diarrhoea IBS (D-IBS) via the Rome III criteria system for IBS diagnosis. DNA and SCFA extractions were optimised for human stool, colonic fluid and tissue biopsy sample obtained from the aforementioned patients. Optimization steps allowed for starting material with high analysis integrity. Different methods of microbiota analysis, such as ARISA, were investigated; however, real-time qPCR was selected as the best method to identify and quantify specific microbiota. Extracted SCFAs were separated via gas chromatography and identified and quantified via Mass Spectrometry. Significant changes in microbial content and SCFA profiles were found to be associated with healthy and IBS patients. Results obtained would however be influenced by external factors typical of clinical studies of this nature. This study allows for opportunities for future research into understanding IBS.

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Bridges, Kayla Marie. "The omega-3 fatty acid content of krill protein concentrate influences bioavailability, tissue deposition, peroxidation, and metabolism in young rats." Morgantown, W. Va. : [West Virginia University Libraries], 2009. http://hdl.handle.net/10450/10241.

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Thesis (M.S.)--West Virginia University, 2009.
Title from document title page. Document formatted into pages; contains vii, 42 p. : ill. Includes abstract. Includes bibliographical references (p. 29-35).

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Bainbridge, Melissa Lee. "Enhancing The Content Of Bioactive Fatty Acids In Bovine Milk For Human Health Promotion And Disease Prevention." ScholarWorks @ UVM, 2017. http://scholarworks.uvm.edu/graddis/695.

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Consumer awareness of the link between dietary fats and health outcomes has led to increased demand for food products enriched with bioactive fatty acids (FA). Ruminant-derived fats, such as dairy fats, contribute significantly to the American diet and contain many unique beneficial FA, such as short- and medium-chain FA, n-3 FA, conjugated linoleic acids (CLA), vaccenic acid (VA), as well as odd-and branched-chain FA (OBCFA). Increasing these FA in dairy products by altering farm management practices, such as breed, lactation stage, and nutrition, may improve human health without a change to the diet. The overarching goal of this dissertation was to evaluate on-farm strategies to increase the content of bioactive FA in bovine milk. The first objective was to enrich milk fat with bioactive FA via supplementation with echium oil, a terrestrial oil rich in n-3 FA. Treatments were 1.5% and 3.0% dry matter as lipid encapsulated echium oil (EEO) which were compared to a control (no EEO). Milk fat contents of n-3 FA increased with EEO supplementation but the transfer of n-3 FA from EEO into milk fat was rather low (< 5%). In a subsequent trial, ruminal protection of EEO and post-ruminal release of EEO-derived FA was examined. EEO-derived FA were preferentially incorporated into plasma lipid fractions unavailable to the mammary gland. Moreover, fecal excretion of EEO-derived FA ranged from 7-14% of intake, and VA and CLA, the biohydrogenation and metabolism products of n-3 FA, increased in milk and feces with EEO supplementation. Therefore, lipid-encapsulation provided inadequate digestibility and low transfer efficiency of n-3 FA into milk. The second objective was to compare the bacterial community structure and unique bioactive FA in bacterial membranes and milk fat between Holstein (HO), Jersey (JE), and HO x JE crossbreeds (CB) across a lactation. Lactation stage had a prominent effect on rumen bacterial taxa, with Firmicutes being most abundant during early lactation. The FA composition of bacterial cells was affected by both lactation stage and genetics, and OBCFA in bacterial cells were positively correlated with several bacteria of the Firmicutes phylum. HO and CB exhibited greater contents of various bioactive FA in milk than JE. The highest content of all bioactive FA occurred at early lactation, while OBCFA were highest at late lactation. The third objective was to determine the effects of grazing a monoculture vs. a diverse pasture on rumen bacterial and protozoal taxa, their membrane FA composition, and milk FA. Microbial communities shifted in response to grazing regime accompanied with changes in their membrane FA profiles. Rumen microbiota from cows grazing a diverse pasture had higher contents of n-3 FA and VA, but lower contents of OBCFA. Microbial membrane FA correlated with microbial taxa, the contents of ALA and n-3 FA were positively correlated with the bacterial genus Butyrivibrio and the protozoal genus Eudioplodinium. Milk contents of CLA and n-3 FA increased when cows grazed a diverse pasture, while grazing a monoculture led to greater milk contents of OBCFA. In conclusion, grazing cows on a diverse pasture, when compared to genetic effects and lipid supplementation, was the most efficacious strategy to increase the content of bioactive FA in milk.

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Sterrett, John, W. Andrew Clark, and Michelle Chandley. "Microbiome Diversity and Differential Abundances Associated with BMI, Immune Markers, and Fecal Short Chain Fatty Acids Before and After Synbiotic Supplementation." Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/honors/536.

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The gut microbiota and its metabolites – namely short chain fatty acids (SCFAs) – interact with the digestive, immune, and nervous systems. Microbiota with disrupted composition are highly associated with obesity, gastrointestinal symptoms, and chronic inflammation. Levels of SCFAs in the feces can represent dynamics of the microbiota, and they represent one mechanism by which the microbiota interacts with its host. This study aimed to further our understanding of associations between microbiota bacterial diversity and SCFAs, immune markers, BMI, and GI symptoms and to identify bacteria that are differentially abundant in different BMI groups and with synbiotic supplementation. Data (SCFAs, immunoglobulins, body mass index, fecal fiber, fecal protein, measures of GI symptoms, and 16s RNA sequences, n=11) was extracted from a randomized control trial investigating the effects of synbiotic supplementation in non-celiac gluten-sensitive participants. QIIME2 was used to process 16s RNA data, analyze quantitative, qualitative, phylogenetic quantitative, and phylogenetic qualitative measures of alpha and beta diversity and to perform an analysis of composition of microbiomes (ANCOM) for identification of differential abundances. Multiple metrics of alpha diversity were found to significantly correlate with IgG4, IgM, IL-2, acetate, propionate, isobutyrate, valerate, isovalerate, caproate, heartburn, urgent need to defecate, and feelings of incomplete evacuation. Multiple metrics of beta diversity were significantly different between normal and overweight, normal and obese, and overweight and obese BMI classification groups. Beta diversity was also found to significantly correlate with IgG1, IgG3, IgG4, IgA, IL-6, IL-8, fecal fiber, propionate, butyrate, heartburn, acid regurgitation, nausea and vomiting, bloating, abdominal distension, increased gas, and eructation. The synbiotic intervention did not significantly alter alpha or beta diversity. An ANCOM identified bacterial taxa differentially abundant with BMI shifts and synbiotic supplementation, though these taxa were not those included in the synbiotic. Findings demonstrate alpha and beta diversity associations with various SCFAs, GI symptoms, immune markers, and BMI, and the results of the placebo-controlled intervention suggest careful consideration of placebo contents moving forward. This research supports plans to apply analysis to larger sample sizes to elucidate changes microbial profiles that are associated with clinically relevant biomarkers and symptoms.

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Mendez, Vanesa. "Carotenoids and Fatty Acids in Early Lactation: A Study of a Peruvian Population." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/3007.

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Lipid soluble carotenoids are micronutrients present in human milk that serve as precursors of vitamin A and also play an important role protecting cells from damage arising from photooxidative processes and reactive oxygen species. Fatty acids comprise about 3-5% of human milk and are mainly present as triglycerides. They are a major energy source for the infant and are necessary to support cell growth required for normal development and maturation of critical organs. Transport of carotenoids into milk has been little studied and there has been no previous investigation of the relationship of carotenoid transport with that of individual fatty acid secretion into milk. In the present study, levels of the carotenoids, lutein, zeaxanthin, b-cryptoxanthin, and b-carotene, in maternal serum, infant cord blood, and milk obtained from 74 Peruvian mothers were measured by HPLC methods. The fat content and fatty acid profile of maternal milk were determined by GC-FID and confirmed by GC-MS. Twenty nine fatty acids were identified and quantified after conversion to methyl esters. Statistical analysis was employed to investigate potential trends and relationships among the carotenoids in all three fluids as well as between carotenoids and fatty acids present. Concentrations of lutein in maternal serum and milk as well as maternal serum and infant cord blood were highly correlated (r =0.43, p

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Garza, Puentes Andrea de la. "Fatty Acids in Obese Pregnancies: Maternal and Child Outcomes." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/457689.

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Maternal obesity has implications on the health of future generations by early life programming. The mother is usually the main source of nutrients for the fetus and neonate, hence her nutritional status is crucial for child development. Fatty acids (FAs), especially long chain polyunsaturated fatty acids (LC-PUFAs), are key nutrients in fetal growth and development. Since these nutrients are known to be altered by conditions such as obesity, maternal obesity could impair fetal/neonatal FA supply, and consequently child outcomes. This thesis presents 4 manuscripts about the influence of maternal pre-pregnancy weight on FA quality and concentrations, along with the implications on maternal and child outcomes. We studied mother-child pairs selected from the total participants in the observational PREOBE cohort study and divided them into 4 groups according to maternal pre-pregnancy body mass index (BMI) and gestational diabetes status; 1) normal-weight, overweight, obese and gestational diabetic. We investigated if FADS and ELOVL genetic variants were associated with pre-pregnancy BMI or affected PUFA levels in plasma of pregnant women. We found that minor allele carriers of FADS1 and FADS2 SNPs had an increased risk for obesity and that the effects of genotype on plasma FA concentrations differed by maternal pre-pregnancy weight status. Enzymatic activity and FA levels were reduced in normal-weight women who were minor allele carriers of FADS SNPs; these reductions were not significant in overweight/obese participants. This suggests that women with a BMI>25 are less affected by FADS genetic variants in this regard. In the presence of FADS2 and ELOVL2 SNPs, overweight/obese women showed higher n-3 LC-PUFA production indexes in plasma than those women in the normal-weight group, but this was not enough to obtain a higher n3 LC-PUFA concentration. We also analyzed the differences in colostrum PUFA composition according to maternal pre-gestational BMI and FADS genotype. A high maternal pre-pregnancy BMI was associated with altered FA levels in colostrum, nevertheless FADS genotypes modulated these results. Minor allele carriers resulted with decreased enzymatic activity and PUFA levels only in normal-weight individuals, making their FA levels similar to those of overweight/obese women. Therefore, FADS genetic variation in overweight/obese women had a different impact, possibly improving their FA status. We also found that dietary intake of DHA in late pregnancy influenced colostrum levels of DHA, thus a high intake of this FA could be a recommendation to improve breast milk composition. Prior to FA analysis in the infants, we validated cheek cells and capillary blood as less invasive alternatives to traditional plasma sampling for FA analysis. We determined the impact of maternal BMI and/or infant feeding practice in infant FA concentrations, and analyzed if these FAs associated with cognitive performance. Maternal pre-pregnancy BMI altered the infant FA behavior in evolution, feeding practice and cognition. In general, FA concentrations decreased towards the 3 years of life, except for the SFAs, n6:n3 and LC-n6:n3 ratios which were increased. Exclusive breastfeeding seemed to rise crucial FAs (e.g. DHA) in infants at 6 months of age, and cognitive performance was found improved in infants with high levels of PUFAs (e.g. DHA, AA) until 1.5 years of age (e.g. n3 PUFAs). These results are a contribution to the scientific evidence of the importance of a healthy pre-pregnancy weight, and identify groups of women who could benefit from an adequate FA intake to pursue better infant outcomes. We therefore should promote a healthy weight and diet in women before, during and after pregnancy to have beneficial effect in children, and consequently prevent some nutrition-related issues through their life.
La obesidad materna tiene implicaciones en la salud de futuras generaciones debido a la programación fetal. Los ácidos grasos (AGs), especialmente poliinsaturados de cadena larga (AGPICL), intervienen en el crecimiento y desarrollo fetal. Dado a que la obesidad puede alterar la concentración de estos AGs, la salud del feto y neonato se compromete. Esta tesis presenta 4 manuscritos sobre el peso materno pre-gestacional en los AGs y sus implicaciones en madre e hijo. Se incluyeron participantes del estudio observacional PREOBE donde se dividen en 4 grupos según el índice de masa corporal (IMC) materno pre-gestacional y estado de diabetes gestacional; 1)normopeso, 2)sobrepeso, 3) obesidad, 4) diabetes gestacional. Se muestra que el alto peso en las mujeres embarazadas altera el comportamiento de los genotipos de las enzimas que intervienen en el metabolismo de los AGs (FADS y ELOVL) y, consecuentemente, afectan los niveles de AGs tanto en plasma como leche materna. Para examinar el perfil de AGs en el niño, primero se validaron la mucosa bucal y sangre capilar como métodos confiables y menos invasivos que la extracción de plasma. Al analizar los AGs del infante, se determina que el IMC materno pre-gestacional altera los niveles de AGs en el niño y cómo éstos se comportan respecto a la evolución, lactancia y cognición. Los resultados de esta tesis aportan evidencia científica sobre la importancia de un peso materno pre- gestacional adecuado; e identifican grupos de mujeres que pueden verse beneficiadas con una apropiada ingesta de AGs con la finalidad de promover el óptimo desarrollo del niño. Por tanto, se debe promover un peso y una dieta adecuada en las mujeres antes, durante y después del embarazo para beneficiar al niño y, consecuentemente, prevenir condiciones adversas en el curso de vida.

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Gigliotti, Joseph Christopher. "Determination of the nutritional value, protein quality and safety of krill protein concentrate isolated using an isolelectric solubilization/precipitation technique." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5471.

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Thesis (M.S.)--West Virginia University, 2007.
Title from document title page. Document formatted into pages; contains vii, 44 p. : ill. Includes abstract. Includes bibliographical references (p. 30-33).

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McGlory, C. "The impact of n-3 PUFA supplementation on human skeletal muscle metabolism." Thesis, University of Stirling, 2014. http://hdl.handle.net/1893/19975.

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The time course of this increase in muscle n-3 PUFA composition and anabolic protein expression is currently unknown. In Chapter 2 of this thesis ten healthy male participants consumed 5g.d-1 of n-3 PUFA-enriched fish oil for 4 weeks. Muscle biopsies samples were collected in the fasted, rested state 2 weeks prior, immediately before (Week 0), at Week 1, Week 2 and Week 4 after initiation of fish oil supplementation for assessment of changes in lipid composition and expression of anabolic signalling proteins over time. Muscle lipid profile, (% total n-3 PUFA/total fatty acids) increased from W0 to W2 (3.8 ± 0.2 to 5.1 ± 0.3 %) and continued to rise at W4 (6.7 ± 0.4 %). Total protein content of FAK increased from W0 to W4 (3.9 ± 1.5 fold) whereas total mTOR was increased from W0 at W1 (2.4 ± 0.6 fold) with no further significant increases at W2 and W4. For the first time this study demonstrates that oral fish oil consumption results in an increase of n-3 PUFA levels in human skeletal muscle that is associated with increases in the expression of anabolic signalling proteins. Our understanding of the anabolic signalling process that underpins muscle protein synthesis has been advanced by the application of the WB technique. However, the semi-quantitative nature and poor dynamic range associated with the WB technique may lead to incongruence regarding the molecular response of skeletal muscle to anabolic stimulation. Chapter 3 of this thesis developed and applied a quantitative in vitro [γ-32P] ATP kinase assay (KA) alongside a traditional WB methodology to assess p70S6K1 signalling responses in human skeletal muscle to RE and protein feeding. Following validation in tissue culture with rapamycin and optimization of the assay in human skeletal muscle, this methodology was tested in a physiologically relevant context. In this regard, six males performed unilateral resistance exercise (RE) followed by the consumption of 20 g of protein. Skeletal muscle biopsies were obtained at pre-RE, at 1 h and 3 h post-RE. In response to RE and protein consumption, p70S6K1 activity was significantly increased from pre-RE at 1 h and 3 h post-RE (8.84 ± 0.78 to 17.18 ± 2.62 and 15.62 ± 3.12 µU/mg). However, phosphorylated p70S6K1thr389 was not significantly elevated. To assess if a combined stimulus of RE and feeding can influence AMPK activity we directly measured AMPK activity. AMPK activity was suppressed from pre-RE at 3 h post-RE (24.15 ± 1.6 to 15.64 ± 1.07 mU/mg), whereas phosphorylated ACCser79 was unchanged. These data therefore highlight the utility of the KA to study skeletal muscle plasticity. Previous studies have shown that ingestion of n-3 PUFA potentiates the phosphorylation of mTORC1 and associated kinases in response to nutrition. However, no study has identified whether n-3 PUFA supplementation potentiates anabolic kinase activity when RE is performed prior to nutrient provision. In Chapter 4 of this thesis, twenty healthy males consumed 5g.d-1 of either fish oil (FO) or coconut oil (CO) capsules for 8 weeks. Muscle biopsy samples were collected in the fasted, rested state before and after 8 weeks of supplementation for assessment of changes in lipid composition. Following 8 weeks of supplementation muscle samples also were obtained at rest (Rest), post RE in both the exercise leg (Post-RE) and the rested leg (Pre-FED) and also at 3 h post RE and protein feeding from both the exercise leg (3 h post-REF) and rested leg (3 h post-FED). There was a 2-fold increase in muscle (5.53 ± 0.3 to 11.16 ± 0.45 % of total fatty acids) n-3 PUFA composition after supplementation in the FO group but no change in the CO group. Following supplementation there was an increase in p70S6K1 activity at 3 h post-REF from Rest in the CO group (5.6 ± 1.4 to 12.2 ± 2.1 µU/mg) but no change in the FO group. In the CO group, AMPKα2 was significantly increased at Post-RE from Rest (3.7 ± 0.7 to 9.9 ± 2.0 mU/mg). These data show that 8 weeks of n-3 PUFA enriched fish oil supplementation suppresses the activity of p70S6K1 in response to RE and protein feeding.

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Dalton, Annalien. "Development and effect of an N-3 fatty acid-rich spread on the nutritional and cognitive status of school children." Thesis, Stellenbosch: University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/1119.

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Thesis (PhD (Food Science))--University of Stellenbosch, 2006.
Long-chain polyunsaturated fatty acids (LCPUFA), especially the n-3 LCPUFA metabolic products eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) play an important role as regulators in many biological processes. To date hake (Merluccius capensis) heads, a rich source of EPA and DHA, have been discarded at sea. The South African Fisheries Policy Development Committee concerned with the environmental impact of this practice has rendered it undesirable. The high prevalence of under-nutrition amongst children in South Africa can be addressed by the supplementation of their diet with this unexploited fish source. The aim of the current study was to develop a microbiologically safe and sensory acceptable sandwich spread using fish flour prepared from fish heads, as a prime ingredient. The intervention trial aimed to compare the effects of an increased dietary intake of n-3 LCPUFA, specifically DHA, on the blood fatty acid levels and absenteeism (as indicator of immune function), as well as the cognitive status, of the subjects. The microbiological content of the sandwich spread was determined after storage for 20 d at 5°C and 15 d at 25°C. Sensory evaluation was performed by consumers (n = 95; M:F = 44:51; 6 – 9 yr) to determine acceptance of the five different flavours individually incorporated into the sandwich spread to mask the fishy note and to provide different flavour options. For the intervention trial subjects (n = 351) were stratified within class group (A - E) and gender and randomly assigned to two treatment categories, an experimental group (EG; n = 174) receiving 25 g sandwich spread.d-1 (191.66 mg DHA. d-1) and a control group (CG; n = 177) receiving an analogous placebo. On school days (104 d), each subject received two sandwiches consisting of two slices of bread (ca. 60 g), spread with 25 g of either the placebo or the experimental spread. Blood samples were drawn at baseline and post intervention. Plasma fatty acid and red blood cell (RBC) membrane status, C-reactive protein levels, as well as vitamin and micronutrient status, were determined. Trained test administrators conducted a battery of cognitive tests. According to South African Government health standards, the sandwich spread remained microbiologically safe after storage. Male and female consumer respondents revealed a significant difference between gender preferences of the five different spread flavours (p <0.05). Significant treatment effects (p <0.05) were observed in n-3 LCPUFA status of the EG, as well as for their absenteeism from school. The two subtests of the Hopkins Verbal Learning test, Recognition and Discrimination Index, showed significant differences between the EG and CG (p <0.05) post intervention in the Grade 2 subjects. The Spelling tests also showed a significant difference between the two groups (p <0.05). In the current study a microbiologically safe and sensory acceptable sandwich spread was developed and tested during an intervention trial, and could possibly in future, provide a healthier option in the School Nutritional Programme. This study proved that supplementation of children (6 - 9 yr) with n-3 LCPUFA, with specific reference to EPA and DHA from a marine source, could have a beneficial effect on their fatty acid status and absenteeism from school. Based on the outcomes of the Hopkins Verbal Learning test and Spelling test, the current study proved that an n-3 fatty acid-rich spread improved the learning ability and memory of children.

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17

Leonard, Franciska. "Modulation of the intestinal vitamin D receptor and calcium ATPase activity by essential fatty acid supplementation." Diss., University of Pretoria, 1999. http://hdl.handle.net/2263/24269.

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18

Leskanich, Christian O'Neil. "Manipulation of the fatty acid composition of porcine tissues with respect to the human diet." Thesis, University of Glasgow, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294169.

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19

Pettit, Patty. "The effects of fatty acid chain length and quantity on the bioavailability of calcium." Virtual Press, 1994. http://liblink.bsu.edu/uhtbin/catkey/917028.

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The purpose of this study was to analyze the effect of fatty acid chain length and quantity on the bioavailability of calcium. Thirteen healthy subjects were randomly assigned to a series of 5 test meals containing varying types and levels of fat and calciumconsumed over a three week time period. The test meals included 10 grams MCT oil (MCT 10), 20 grams MCT oil (MCT 20), 10 grams beef fat (BT 10), 20 grams beef fat (BT 20), and calcium only (Ca). Calcium absorption was assessed using timed urine collections following a specified calcium load. Three day food records were obtained to assess typical nutrient intakes of the subjects coming into and during the study. MCT oil provided better absorption of the calcium supplement than did the beef tallow. A difference was also noted in the absorption of calcium based on the amount of fat consumed. A higher intake of MCT oil (10 g vs. 20 g) appeared to favor the absorption of calcium. Urine calcium excretion was significantly greater (p < .009) during the MCT oil treatments (MCT 10, MCT 20) compared to the beef fat treatments (BT 10, BT 20), suggesting reduced calcium absorption during the beef fat treatments. There were no differences in mean calcium excretion based on quantity of fat consumed ( 10 g vs. 20 g), nor any interaction between type of fat and amount. Tests for detecting differences between individual treatments indicated a significance difference (p < .05) in calcium excretion between MCT 20 and BT 10 treatments. Urine calcium excretion was corrected for body size using urine calcium/creatinine ratio (Ca/Cr). There was a significant time effect between the 0 - 2, 2 - 4 hour time periods (p < .005) and the various treatments for Ca/Cr. Though not significant, mean Ca/Cr was highest for the calcium treatment (0.42), compared to the MCT oil treatments (36, z of MCT 10 & MCT 20), and beef fat treatments (28, x of BT 10 & BT 20). The beef fat treatments significantly decreased the absorption of calcium compared to the MCT oil treatments. It appears that beef fat, when compared to the calcium only treatment, decreased calcium absorption.
Department of Home Economics

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20

Agans, Richard Thomas. "Modeling Effects of Diet on Human Gut Microbiota." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1472128769.

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21

Kwon, Megan R. "Nutrient Content of Human Breast Milk from Overweight and Normal Weight Caucasian Women of Northeast Tennessee." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etd/3192.

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Many factors influence the nutrient composition of breast milk (BRM) particularly within the fatty acids composition. In this study BRM between 2-14 weeks of lactation was collected from 44 Caucasian women (24 normal weight (NW, BMI 18.5-24.9kg/m2) and 20 overweight (OW, BMI >25.0kg/m2). BRM was subjected to proximate analysis and participants completed food frequency questionnaires (FFQ) to estimate fruit, vegetable, and fat intake. BMI differed between NW and OW groups, 22.03 vs 33.86kg/m2 (p0.10) were identified for total calories (5,581.8 vs 5562.9cal/g), %fat (39.6 vs 43.9), or %protein (9.8 vs 8.9) for BRM in NW versus OW women as determined by proximal analysis. Gas chromatography of fatty acid methyl esters demonstrated NW BRM contained higher levels of omega-3, mono-unsaturated, and less palmitic acid fatty acids (p>0.10). The increased palmitic acid level seen in OW BRM may support increased de novo synthesis of fatty acids.

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22

DeLany, James Patrick. "Effects of fish oil on serum lipids in college men in a controlled feeding trial /." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487268021749804.

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23

Kennedy, Sean Robert. "Bioactive fatty acids as dietary supplements for farmed fish : effects on growth performance, lipid metabolism, gene expression and immune parameters." Thesis, University of Stirling, 2007. http://hdl.handle.net/1893/389.

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Current feed formulations within the aquaculture industry have tended to rely on high dietary lipid thus offsetting relatively expensive protein as a source of energy. In this way, protein can be ‘spared’ for synthesis of new tissue and the high lipid content can also fulfil both fish and consumer essential fatty acid (EFA) requirements. However, the main disadvantage of feeding high lipid levels to farmed fish is a surplus of fat deposition in the flesh and other important tissues, which can detrimentally impact on quality characteristics central to the human consumer. However, based on previous work in other animal models, it is entirely feasible that supplementation of the diet with bioactive fatty acids such as conjugated linoleic acid (CLA) and tetradecylthioacetic acid (TTA) may mitigate the deleterious effects of feeding farmed fish high fat diets by reducing fat deposition in particular. The general objective of this research work was to test the hypothesis that CLA and/or TTA could augment growth, reduce fat deposition and enhance fatty acid composition via incorporation of these bioactive fatty acids, and increase n-3 highly unsaturated fatty acid (HUFA) levels in the flesh of commercially important fish species such as Atlantic salmon (Salmo salar), Atlantic cod (Gadus morhua L.) and rainbow trout (Oncorhynchus mykiss). This project also considered the influence of CLA and TTA on enzymes and transcription factors thought to be pivotal in lipid metabolism and fatty acid oxidation in particular. A subsidiary aim of this research work was to investigate the immunological impact of dietary CLA and TTA administration in these fish. The results of this project have revealed that the hypothesis was only partly proved. There was no effect in growth or biometry after either CLA or TTA supplementation in any of the fish species investigated. Additionally, there were few physiologically significant effects on fat levels on fish as a result of TTA or CLA administration. However, there were a number of effects on fatty acid metabolism including inhibition of steroyl coenzyme desaturase (SCD) in cod and trout in particular and also enhancement of hepatic n-3 HUFA levels in trout. Importantly, it was determined that both TTA and CLA could be incorporated into the flesh thus providing a vehicle through which these bioactive fatty acids can be delivered to the consumer. There were also a number of beneficial effects on activity and gene expression of a number of enzymes and transcription factors thought to be fundamental to the modulation of fatty acid oxidation in particular. However, the effects on gene transcription and biochemistry had little impact at the whole body level. This research work also showed that there were no detrimental effects on immune status after supplementation with dietary CLA or TTA. Conclusively, this thesis has contributed to the overall understanding of the influence of dietary CLA and TTA in farmed fish.

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24

Smith, Bryan K. "Exercise and fish oil : additive effect on postprandial lipemia? /." free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3074443.

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25

Mogongoa, Lebogang Francis. "The effect of short-chain fatty acids on some haemostatic risk markers in westernised black men." Thesis, Bloemfontein : Central University of Technology, Free State, 2007. http://hdl.handle.net/11462/80.

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Thesis (M. Tech.) -- Central University of Technology, Free State, 2007
Cerebrovascular disease and coronary heart disease (CHD) are of the most important causes of morbidity and mortality amongst South Africans. The risk factor prevalence for stroke and CHD becomes altered by changes in lifestyle, including diet. In general it is suggested that lifestyle management should be the first choice when having to treat patients with increased cardiovascular risk. The prudent low-fat, high-fibre diet is regarded as an apparently healthy diet. It is suspected that this diet is effective for the control of known coronary risk factors as well as raised clotting factors. Research studies have shown the addition of dietary fibre to the diet as a promising therapeutic agent for the limited control of known coronary risk factors. The physiological effects of dietary fibre in humans are significantly influenced by the degree to which fibre is fermented in the colon. Fermentation results in the production of short-chain fatty acids (SCFAs); acetate, propionate and butyrate. The aim of this study was to examine the possible effects of different combinations of short-chain fatty acids on some metabolic risk markers. In this study a group of westernised African male volunteers was recruited and randomly assigned to three groups. Group one received a placebo. Group two received a supplement containing 50% acetate and 50% propionate. Group three received a SCFA supplement in the ratio of 70% acetate, 15% propionate and 15% butyrate. Supplementation was sustained for a period of six weeks. Blood samples were drawn during the different visits. At baseline the study group represented a group of black African men without any apparent metabolic or physical abnormalities. All measured variables fell within the normal range. In the placebo group, there was a statistically significant decrease in plasma fibrinogen levels from baseline to the end of supplementation. In the acetatepropionate supplement study group a statistically significant decrease in factor VIII (from 91.1 ± 11.2 to 90.9 ± 8.3%, respectively), and ATIII (from 114.3 ± 13.1 to 108.34 ± 9.5%), as well as a statistically significant decrease in low-density lipoprotein cholesterol (LDL-C) from 3.10 ± 0.79 to 2.64 ± 0.73 mmol/L. The significant increase in %HDL-C from 26.3 ± 6.5 to 30.2 ± 9.3% should also be noted. Both triglycerides (8%) and plasma fibrinogen (2%) showed a statistically significant increase. However, these changes are of no clinical significance. For the high-acetate supplement study group (with the addition of butyrate), a statistically significant decrease in factor VII (from 102.5 ± 13.7 to 101.1 ± 6.4%), VIII (from 92.6 ± 12.8 to 87.6 ± 6.0%), ATIII (from 109.2 ± 16.0 to 103.0 ± 9.9%) as well as fibrin monomer concentration (from 13.9 ± 2.2 to 12.1 ± 3.6 mg/L), were measured. Fibrin network compaction increased significantly from 14.2 ± 4.6 to 13.7 ± 4.0%. Other changes include a statistically significant increase in the serum-TC of 4.2%. From the results it is evident that the acetate-propionate supplement, with exclusion of butyrate, has a beneficial effect on metabolic parameters when compared to a highacetate- propionate supplement. The results do provide evidence of a possible therapeutic application for the propionate-acetate containing supplement. The specific mechanism should, however, still be investigated. It can be concluded from this study that acetate, propionate and butyrate each have different effects on human metabolism. It is evident that the use of a mixture of acetate and propionate may have a beneficial effect on patients at risk of developing CVD. Further studies that investigate the optimum ratio of these two products may lead to the development of a naturally derived therapeutic product for the prevention or treatment of CVD in black African men, as well as the population at large.

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26

MANCINO, ROBERTA. "Influence of cow diet on nutritional profile of milk and dairy products and effects on alterations of human gut microbiota by an in vitro digestion model." Doctoral thesis, Università di Foggia, 2018. http://hdl.handle.net/11369/363264.

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I consumatori richiedono costantemente la presenza sul mercato di alimenti salutistici, che in termini di latte e prodotti lattiero-caseari si traducono in un latte con percentuali più elevate di acidi grassi “sani” come gli acidi grassi polinsaturi (PUFA), ed una più bassa percentuale di acidi grassi saturi (SFA). Il latte e prodotti lattiero-caseari contribuiscono in modo significativo all’assorbimento di sostanze nutritive essenziali nella dieta. Nonostante ciò, il consumo di latte ha fatto registrare un’inflessione a causa delle linee guida nutrizionali che suggeriscono di limitare il consumo pro capite di SFA, che per una parte significativa provengono da latte e derivati (USDA e HHS, 2010). Una strategia per migliorare il profilo di FA di latte e prodotti lattiero-caseari è l'integrazione della dieta bovina con semi oleaginosi, che diminuiscono la percentuale di SFA nel latte, diminuendo la sintesi de novo di FA nella ghiandola mammaria. Da precedenti sperimentazioni emerge che la supplementazione di semi di lino nella dieta delle bovine da latte riduce le concentrazioni di acidi grassi a corta catena corta e acidi grassi a media catena, ed aumenta il contenuto di acidi grassi a lunga catena nel grasso del latte. Tuttavia, l’inclusione dei semi oleaginosi, in particolare dei semi di lino, nella dieta della vacca da latte, scoraggia gli allevatori dal loro utilizzo, a causa del costo molto elevato. É necessario, quindi, trovare un compromesso tra costi aggiuntivi stimati e la giusta quantità di semi oleaginosi da somministrare nella dieta degli animali per migliorare la produzione di latte e la sua composizione. In Italia, circa l'80% delle aziende lattiero-casearie utilizza vacche di razza Frisona per la produzione lattea da destinare sia al consumo diretto che alla produzione di formaggio. Le bovine di razza Jersey vengono utilizzate per migliorare l'efficienza del settore della produzione di formaggio in diverse parti del mondo. Il tratto gastrointestinale costituisce la più grande interfaccia del corpo con l'ambiente esterno ed è esposto ad una grande quantità di materiale estraneo, inclusi batteri patogeni e commensali, così come antigeni alimentari. La tolleranza orale è una proprietà importante del sistema immunitario intestinale; l’omeostasi intestinale richiede interazioni equilibrate tra il microbiota intestinale e gli antigeni alimentari. Alla nascita, siamo colonizzati da una complessa comunità di cellule mcrobiche che arriva fino a una densità di 1 × 1012 cellule batteriche per grammo di microbi contenuti nel colon adulto. Queste cellule microbiche vivono in una relazione simbiotica con l'ospite e sono determinanti in materia di salute e di malattia, influenzando l'assorbimento dei nutrienti, la funzione di barriera e lo sviluppo del sistema immunitario. Sulla base delle considerazioni precedenti gli scopi del presente lavoro di tesi sono: 1. cercare di ridurre la quantità giornaliera di semi di lino somministrati agli animali per incoraggiare il loro utilizzo da parte degli allevatori per aumentare il contenuto di acidi grassi polinsaturi nel latte a scapito degli acidi grassi saturi con una connotazione salutistica del latte prodotto; 2. testare gli effetti della somministrazione di semi di lino su due diverse razze da latte: Frisona e Jersey; 3. valutare il trasferimento di acidi grassi polinsaturi in due diversi prodotti lattiero-caseari (Caciotta vs Caciocavallo) con tempi di stagionatura diversi; 4. valutare gli effetti dei prodotti lattiero-caseari naturalmente arricchiti in acidi grassi polinsaturi sulla salute umana di un modello di digestione in vitro con la valutazione di: a) variazioni di profilo degli acidi grassi di prodotti lattiero-caseari dopo la digestione in vitro; b) acidi grassi a catena corta (SCFA) prodotti dal gut microbiota; c) variazioni della flora intestinale tramite fermentazione fecale seguito da pirosequenziamento. Dai risultati ottenuti il contenuto elevato di latte C18:3n3 nel latte suggerisce che la riduzione della quantità di supplementazione di semi di lino nella dieta delle bovine può migliorare latte profilo di acidi grassi con una consistente riduzione dei costi di produzione; le razze sottoposet alla sperimentazione, Frisona e Jersey hanno risposto in modo diverso alla stessa supplementazione di semi di lino. Gli acidi grassi polinsaturi sono stati trasferiti nei prodotti lattiero caseari, soprattutto nella Caciotta, suggerendo un ruolo determinante del protocollo di caseificazione nel trasferimento della tipologia di acido grasso della dieta. Dopo la digestione in vitro, gli acidi grassi rimangono nel digerito gastro-intestinale; la loro presenza può avere effetti benefici sul tratto gastrointestinale e di conseguenza sulla salute umana. Inoltre la presenza e la quantità di acidi grassi a catena corta (SCFA) ritrovata nei fermentati fecali suggeriscono alcuni cambiamenti delle popolazioni microbiche indotte dalla presenza dei prodotti lattiero caseari sperimentali, lasciando intravedere importanti effetti benefici sulla salute umana.
Health-conscious consumers are demanding milk with higher proportions of healthy fatty acids as polyunsatured fatty acids (PUFA), and lower proportion of saturated fatty acids (SFA). Milk and dairy products contribute significantly to the consumption of essential nutrients in human populations. Despite its important roles in human nutrition, consumption of milk has declined, because nutritional guidelines have limited capita consumption of SFA, which to a significant proportion originate from milk and dairy products (USDA and HHS, 2010). A strategy to improve the FA profile of milk and dairy products is the supplementation of cow’s diet with oilseeds, which decrease the proportion of SFA, by decreasing de novo FA synthesis in the mammary gland. Feeding flaxseed to dairy cows decreases the concentrations of short-chain fatty acids and medium chain fatty acids and increases the long-chain fatty acid content in milk fat. However, oilseeds, and in particular flaxseed, have a very high costs that discourage farmers in their utilization. It’s necessary, therefore to find a compromise between costs and the right amount to be administered in the diet to the animals to ameliorate milk yield and composition. In Italy, about 80% of dairy farms produce milk of Friesian cows both for direct consumption and for cheese production. Jersey breed and it has been used to improve the efficiency of the cheesemaking sector in different part of the world, and is characterized by improved longevity, superior udder health, higher cheese yield, reduced feed and water requirement. The gastrointestinal tract constitutes the body’s largest interface with the external environment and is exposed to a vast amount of foreign material, including pathogenic and commensal bacteria, as well as food antigens. Oral tolerance is an important property of the gut immune system; intestinal homeostasis requires balanced interactions between the gut microbiota, dietary antigens. At birth, we are colonized with a complex community of microbes that reaches up to a density of 1 × 1012 bacterial cells per grams of content in the adult colon. These microbes live in a symbiotic relationship with the host and they are determinants in health and disease influencing nutrient absorption, barrier function and immune development. On the basis of the previous considerations and considering that oil seeds are expensive and many farmers are reluctant to use them the aims of this PhD thesis are: 1. trying to reduce the daily amount of flaxseed administered to animals in order to increase the content of polyunsaturated fatty acids in milk at the expense of saturated fatty acids, and to encourage its utilization by farmers as supplements to dairy cows with a reduction of management costs; 2. testing the effects of flaxseed administration on two different dairy cows breeds: Friesian and Jersey; 3. evaluating the transferring of polyunsaturated fatty acids in two different dairy products (Caciotta vs Caciocavallo) at different ripening time; 4. evaluating the effects of dairy products naturally enriched in polyunsaturated fatty acids on human health by an in vitro digestion model with the evaluation of changes in: a) fatty acid profile of dairy products after in vitro digestion; b) short chain fatty acids (SCFA) produced by gut microbiota; c) changes in gut microbiota populations by fecal fermentation followed by pyrosequencing. The higher milk content of C18:3n3 in milk suggests that the reduction in the amount of flaxseed supplementation can also improve milk fatty acid profile with a consistent reduction of production costs; however, Friesian and Jersey cows replied differently to the same flaxseed supplementation; Polyunsatured fatty acids are transferred into dairy products, especially in Caciotta cheese, suggesting that probably the different cheese making influenced the transferring. After in vitro digestion, fatty acids remain in the digest; their presence can have beneficial effects on the gastrointestinal tract and consequently on human health. Moreover the presence and the amount of short chain fatty acids (SCFA) could suggest some changes of microbiological populations that could have beneficial effects on human health.

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Rubio, Mejia Olga Liliana. "The CHSE-214 salmon cell line as a model to study molecular regulation of long-chain polyunsaturated fatty acid biosynthesis in salmonids." Thesis, University of Stirling, 2015. http://hdl.handle.net/1893/21807.

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The main source of omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA) in our diet is supplied by fish, and an ever-increasing proportion of these are being produced by aquaculture. The drive for the growing market demand and production from sustainable sources has led to the use of high-energy (fat) diets and, recently, to the replacement of fishmeal and fish oil with non-marine components, such as plant meals and vegetable oils that are devoid of n-3 LC-PUFA. Both changes impact greatly on lipid and fatty acid metabolism in fish, with health implications for the fish and the human consumer. This impact highlights the need to investigate the basic molecular mechanisms underlying the regulation of lipid and fatty acid metabolism in fish, specifically focussing on the pathways of lipid homeostasis and LC-PUFA synthesis. The aim of this study was to develop and utilise Chinook salmon embryo (CHSE-214) cell line as a model for Atlantic salmon, Salmo salar L., to enable an integrated approach to study the biochemical and molecular regulation of lipid metabolism in fish. In particular, α-linolenic acid (LNA, 18:3n-3) and linoleic acid (LOA, 18:2n-6), which are essential fatty acids abundantly found in vegetable oils, and are precursors of LC-PUFA, were supplemented in combination with other fatty acids, to explore the effect of these on total lipid content, lipid class, FA composition and gene expression of CHSE-214 cell line. Total lipid content was extracted, followed by determination of lipid class and fatty acid analyses. Gene expression analyses of transcription/nuclear factors and various target genes in Atlantic salmon, including those involved in pathways of LC-PUFA synthesis and fatty acid oxidation, were carried out. The results demonstrated that CHSE-214 cell line, under experimental conditions, is able to convert LNA to eicosapentaenoic acid (EPA, 20:5n-3), and LOA to arachidonic acid (ARA, 20:4n-6), but not LNA and/or EPA to docosahexaenoic acid (DHA, 22:6n-3), highlighting the activity of elongase and desaturase enzymes during the conversion process. Changes occurring on the fatty acid profile and also at molecular level were observed. Understanding the role that transcription factors play in the regulation of lipid biosynthesis in fish will allow endogenous LC-PUFA synthesis to be optimised. The results from this study could be used to improve the efficiency of alternative, sustainable diets in aquaculture, while maintaining the nutritional quality of farmed fish for the final consumer. CHSE-214 cell line can therefore be used as a model to study the molecular mechanisms involved in the LC-PUFA biosynthesis, particularly in the conversion of LNA to EPA, which can then be reproduced in vivo, saving time and money.

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28

Jankord, Ryan. "Modulation of the ACTH response to stress by IL-6, nitric oxide, diet and exercise." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4418.

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Thesis (Ph. D.)--University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Vita. "December 2006" Includes bibliographical references.

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Freitas, Ronilson Ferreira. "Rela??o entre o ?ndice de qualidade da dieta de nutrizes e o perfil de ?cidos graxos do leite materno." UFVJM, 2016. http://acervo.ufvjm.edu.br/jspui/handle/1/1307.

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O objetivo deste estudo foi avaliar e relacionar a qualidade da dieta materna e a composi??o do leite humano em ?cidos graxos no primeiro trimestre de lacta??o. Trata-se de um estudo epidemiol?gico observacional, transversal que foi desenvolvido no per?odo de agosto de 2014 ? dezembro de 2015. A amostra constituiu-se de 106 nutrizes residentes na zona urbana da cidade de Diamantina, Minas Gerais, Brasil. Os instrumentos de coleta dos dados foram question?rio semiestruturado para caracteriza??o da amostra e o recordat?rio de ingest?o habitual. A qualidade da dieta foi avaliada por meio do ?ndice de Alimenta??o Saud?vel validado para a popula??o brasileira (IAS). Amostras de leite materno maduro foram obtidas de 106 nutrizes, a partir da 5? semana p?s-parto, por meio de ordenha manual. A extra??o da gordura do leite foi realizada atrav?s do m?todo de Bligh-Dyer, e metiladas com met?xido de s?dio 0,25 mol/l em metanol dietil ? ?ter. O perfil de ?cidos graxos do leite foi determinado por um Cromat?grafo a G?s equipado com detector por ioniza??o de chamas. Para as an?lises deste estudo, foram estimadas as porcentagens m?dias e desvios padr?o, as medianas e intervalos interquart?licos. Utilizou-se o teste de Kolmogorov-Sminorv para testar a normalidade dos dados. Foi realizado teste de Correla??o de Pearson e de Spearman, para verificar associa??o entre as vari?veis. Posteriormente foi realizada a an?lise de regress?o linear m?ltipla e an?lise de regress?o multivariada. A pontua??o m?dia do IAS total de 64,36?10,68 e os alimentos do grupo das frutas total, fruta inteira, cereal total, cereal integral e leite e derivados, foram os componentes do IAS das nutrizes com menores pontua??es, e com maior frequ?ncia de nota m?nima. Foi poss?vel observar um baixo consumo de frutas totais, frutas inteiras, cereais totais, cereais integrais e leite e derivados. Dentre os ?cidos graxos saturados, foram observados valores mais elevados para os ?cidos graxos palm?tico (C16:0), este?rico (C18:0), mir?stico (C14:0) e l?urico (C12:0), respectivamente. Entre os ?cidos graxos mono-insaturados, verificou-se maior contribui??o dos ?cidos graxos oleico (C18:1) e palmitoleico (C16:1), respectivamente. O total de ?cidos graxos essenciais (linoleico e ?- linol?nico) foi de 14,94%.Foi poss?vel observar uma rela??o inversa entre o consumo de frutas totais com o perfil de ?cidos graxos poli-insaturados, e uma rela??o direta entre o consumo de frutas totais e cereais totais com os ?cidos mono-insaturados e saturados, o que sugere que a qualidade da dieta reflete na composi??o de ?cidos graxos do leite materno.
Disserta??o (Mestrado Profissional) ? Programa de P?s-Gradua??o em Sa?de, Sociedade e Ambiente, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016.
The aim of this study was to evaluate and relate the quality of maternal diet and the composition of human milk fatty acids in the first quarter of lactation. This is an observational epidemiological study, cross that was carried out from August 2014 to December 2015. The sample consisted of 106 nursing mothers living in the urban area of the city of Diamantina, Minas Gerais, Brazil. Collection instruments data were semi-structured questionnaire to characterize the sample and usual intake recall. The quality of the diet was assessed by the Healthy Eating Index validated for the Brazilian population (IAS). Mature human milk samples were obtained from lactating 106, from the 5th week after birth, by manual milking. The extraction of milk fat was performed using the Bligh-Dyer method and methylated with sodium methoxide 0.25 moles/l in methanol diethyl - ether. The profile of fatty acids of milk was determined by a gas chromatograph equipped with a flame ionization detector. For the analysis of this study, the estimated mean and standard deviation percentages, medians and interquartile ranges. We used the Kolmogorov-Sminorv test to test the normality of the data. It was performed Pearson correlation test and Spearman to verify associations between variables. Later it was performed the analysis of multiple linear regression and multivariate regression analysis. The average score of all IAS 64.36?10.68 and the food group of all fruits, whole fruit, whole grain, whole grain and dairy products, were the components of the IAS of nursing mothers with lower scores, and more frequency minimum score. It was observed a low intake of total fruits, whole fruits, total grains, whole grains and dairy products. Among the saturated fatty acids, higher values were observed for palmitic fatty acid (C16: 0), stearic (C18: 0), myristic (C14: 0) and lauric (C12: 0), respectively. Among the mono-unsaturated fatty acids there was a higher contribution from the fatty acids oleic (C18: 1) and palmitoleic (C16: 1), respectively. The total essential fatty acids (linoleic and linolenic ?-) was 14.94%. It was observed an inverse relationship between the intake of total fruit with the profile of polyunsaturated fatty acids, and a direct relation between the consumption of total fruit and total cereal with the monounsaturated and saturated acids, which suggests that the quality diet reflects the fatty acid composition of breast milk.

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Nälsén, Cecilia. "Measurement and Evaluation of Antioxidant Status and Relation to Oxidative Stress in Humans." Doctoral thesis, Uppsala University, Clinical Nutrition Research, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6742.

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Numerous diseases are associated with reduced antioxidant defence and oxidative stress. The antioxidant defence includes dietary and endogenous antioxidants and involves complex interactions between them. The effects of dietary factors on antioxidant status and oxidative stress of healthy humans were investigated in the studies described in this thesis. Assays of plasma antioxidant capacity encompass interactions between various antioxidants. Although uric acid has an unclear function as an antioxidant, it is a major determinant of antioxidant capacity. We measured antioxidant capacity in the presence and absence of uric acid to provide more information on the application of measures of antioxidant capacity. Individuals with high dietary intakes of various antioxidants and antioxidant rich foods, especially when combined, had higher plasma antioxidant capacities than those with lower antioxidant intakes. However, there were no associations between dietary intake of antioxidants or antioxidant rich foods and the plasma concentration of F₂-isoprostanes, which is considered a reliable biomarker for oxidative stress. Intakes of various doses of a mixture of bilberry juice and black tea, rich in flavonoids for four weeks, increased antioxidant capacity in some groups, but urine levels of F₂-isoprostanes were not affected. There were substantial individual variations in responses to the drinks related to baseline antioxidant capacity. Supplementation with eicosapentaenoic acid and docosahexaenoic acid decreased the plasma levels of F₂-isoprostanes, but not prostaglandin F_2α formation or antioxidant capacity.

It was concluded that a high intake of foods rich in antioxidants is related to improved antioxidant status. After intake of foods rich in antioxidants, the antioxidant status may increase, but with considerable individual variation in the responses, which warrants further investigation. Lipid peroxidation in vivo is not easily affected by dietary antioxidants in healthy humans. Although n-3 fatty acids are highly unsaturated, they reduce nonenzymatic free radical-catalyzed lipid peroxidation, but not enzymatic lipid peroxidation.

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Du, Toit Joe-Lin. "The modulation of various signal transduction pathways in colorectal carcinoma cells by docosahexaenoic acid." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/17350.

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Thesis (MSc)--University of Stellenbosch, 2006.
ENGLISH ABSTRACT: Introduction: The ability of different polyunsaturated fatty acids (PUFAs), especially n-3 PUFAs, to prevent the development of cancer has been under intense investigation the past three decades. Numerous studies have shown that these fatty acids can kill cancer cells in vitro as well as in vivo whilst normal cells remain unaffected. Unfortunately, the cellular and molecular mechanisms responsible for this phenomenon are still poorly understood. This study investigated the signalling pathways modulated by docosahexaenoic acid (DHA) in an adenocarcinoma cell line, in order to shed some light on these unknown mechanisms. Materials & Methods: NCM460 (normal colon epithelial) and CaCo2 (colon adenocarcinoma) cells were cultured and treated with low doses of palmitic acid (PMA), oleic acid (OA), arachidonic acid (AA), and DHA. The effects of these fatty acids on the proliferation of the cells were measured with the MTT assay. The composition of membrane phospholipids of CaCo2 cells was determined after 48h supplementation with different fatty acids by gas chromatography. Also, CaCo2 cells were treated with DHA (10 μM) only and proteins were harvested at fixed time points ranging from 2 minutes to 48 hours. The protein inhibitors wortmannin (PI3 kinase inhibitor), PD 98059 (MEK inhibitor) and SB 203580 (p38 inhibitor) and also RNA interference (RNAi) of the p38 MAPK protein were used to investigate cross-talk between signalling pathways. ERK, p38 MAP kinase, Akt, and p53 were then analysed by Western blotting using phospho-specific and total antibodies. The cleavage of the apoptotic proteins, caspase-3 and PARP were also analysed. Results and discussion: MTT assays revealed that none of the fatty acids were toxic to normal cells. In addition, DHA was shown to be most effective to kill CaCo2 cells whilst protecting NCM460 cells and a subsequent dose response experiment revealed that lower concentrations are most suitable for this purpose. DHA was also shown to be readily incorporated into phospholipids, along with AA. This is associated with increased membrane fluidity, which could affect the localisation, and downstream effects, of various signalling proteins within the membrane. Western blot analysis revealed a rapid increase in activity in most proteins under investigation, especially ERK and Akt (Ser473). Long-term DHA supplementation suppressed the full activation of Akt. This down regulation of survival signalling could lead to cell death in CaCo2 cells. In addition, it was shown that after 48h, DHA induced the cleavage of caspase-3 and PARP, which is indicative of apoptosis. RNAi experiments suggested a possible role for p38 MAPK in the phosphorylation of p53 at Ser15, a site which is associated with DNA damage. Conclusion: DHA exerts its effects by means of cellular signal transduction pathways, particularly by suppression of the important survival-related kinase, Akt. This could have implications for future therapeutic interventions in cancer patients, as fatty acids are safe to use and do not interfere with the functionality of normal tissue.
AFRIKAANSE OPSOMMING: Inleiding: Die vermoë van verskillende poli-onversadigde vetsure (POVSe), veral n-3 POVSe, om die ontstaan van kanker te voorkom, is intens nagevors die afgelope drie dekades. Menigte studies het aangevoer dat hierdie vetsure kankerselle in vitro asook in vivo kan doodmaak, terwyl normale selle nie daardeur beïnvloed word nie. Ongelukkig word die sellulêre and molekulêre meganismes onderliggend tot hierdie verskynsel nie goed begryp nie. Hierdie studie het verskeie seintransduksie-paaie wat deur dokosaheksaenoësuur (DHS) in ‘n adenokarsinoom sellyn gemoduleer word, ondersoek. Materiale & Metodes: NCM460 (normale kolonepiteel) en CaCo2 (kolon adenokarsinoom) selle is onderhou in ‘n selkultuur-laboratorium en behandel met lae dosisse palmitiensuur (PMS), oleïensuur (OS), aragidoonsuur (AS), en DHS. Die invloed van hierdie vetsure op die proliferasie van die selle is d.m.v. die MTT toets bepaal. The samestelling van membraan-fosfolipiede van CaCo2 selle is na 48h behandeling met die verskillende vetsure bepaal deur middel van gaschromatografie. Die CaCo2 selle is ook met DHA (10 μM) alleenlik behandel en teen vaste tydpunte wat wissel van 2 minute tot 48h, waarna proteïene geëkstraeer is. Die proteïen-inhibitore wortmannin (PI3 kinase inhibitor), PD 98059 (MEK inhibitor), en SB 203580 (p38 inhibitor) asook RNAinterferensie (RNAi) teen die p38 MAPK proteïen is ingespan om oorvleueling tussen seintransduksie–weë te ondersoek. ERK, p38 MAPK, Akt, en p53 is geanaliseer deur middel van die Western–klad metode met fosfo–spesifieke en totale antiliggame. Die kliewing van die apoptotiese proteïene caspase-3 en PARP is ook bepaal. Resultate en bespreking: MTT toetse het ontul dat geen vetsure toksies was vir die normale selle nie. Daar is ook gevind dat DHS die mees effektiewe vetsuur was om CaCo2 selle te dood, terwyl NCM460 selle beskerm word. Gevolglik het ‘n dosis-respons eksperiment getoon dat laer konsentrasies die beste geskik is vir hierdie doel. Daar is ook gevind dat DHA maklik in fosfolipiede geïnkorporeer word, tesame met AS. Dit word geassosieer met verhoogde membraan-vloeibaarheid, wat die ligging, en ook stroom-af werking, van verskeie seintransduksie proteïene in die membraan, kan beïnvloed. Westernklad analises het ‘n vinnige verhoging in die aktiwiteite van die meeste proteïene onder die soeklig, getoon, veral ERK en Akt (Ser473). Langdurige DHS behandeling het die maksimale aktiwiteit van Akt onderdruk. Hierdie afname van oorlewing-gerigte seine kan lei tot seldood in CaCo2 selle. Daar is boonop geving dat DHS die kliewing van caspase-3 en PARP geïnduseer het na 48, wat dui op apoptose. Uit die RNAi eksperiment kon daar ook ‘n moontlike rol vir p38 MAPK in die fosforilering van p53 by Ser15, wat geassosieer word met DNS-skade, getoon word. Gevolgtrekking: DHS beoefen sy effekte deur middel van seintransduksie paaie, veral deur die oorlewing-geassosieerde kinase, Akt, te onderdruk. Dit kan implikasies hê vir toekomende terapeutiese ingrypings in kankerpasiënte, aangesien vetsure veilig is om te gebruik en nie skadelik is vir normale weefsel nie.

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Guelzim, Najoua. "Régulation du métabolisme secondaire de l'arginine et de la cystéine par l'acide alpha-linolénique. Implication dans la physiopathologie du syndrome métabolique." Phd thesis, AgroParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00781861.

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Si l'intérêt nutritionnel des acides gras polyinsaturés (AGPI) n-3 dans la prise en charge et la prévention des dysfonctions associées au syndrome métabolique, est bien établi. Les mécanismes d'action spécifiques sous-jacents aux effets bénéfiques de cette famille d'acides gras sont encore en cours d'étude. L'objectif de ces travaux était d'explorer le rôle de l'acide alpha-linolénique ALA ou 18 :3 n-3, dans la modulation des voies affectant l'homéostasie de molécules bioactives dérivant du métabolisme secondaire des acides aminés (le monoxyde d'azote -NO- et le glutathion). L'hypothèse sous-jacente est que ces modulations pourraient expliquer, du moins en partie, le rôle des AGPI n-3 dans le maintien des fonctions biologiques contrôlées par ces métabolites (telles que la fonction endothéliale et le statut oxydant) et impliquées de près dans la physiopathologie du syndrome métabolique. Notre intérêt a porté particulièrement sur la voie de régulation génique via le PPARα et sur son implication dans le contrôle des gènes du métabolisme des acides aminés par l'ALA. Nous avons exploré chez la souris de type sauvage et invalidée pour le PPARα, l'effet de l'apport alimentaire d'ALA dans le cadre de régime normo- ou hyper-lipidiques sur les voies du métabolisme secondaire de l'arginine et de la cystéine. En parallèle nous nous sommes focalisés sur les effets de l'ALA au niveau vasculaire en utilisant un modèle de cellules endothéliales bovines en cultures. De ce travail de thèse s'est dégagé que l'ALA module effectivement le métabolisme secondaire de l'arginine et de la cystéine. L'apport d'ALA (à hauteur de 11% et 42% de l'apport énergétique) augmente la production de NO sans affecter l'expression hépatique des enzymes contrôlant l'utilisation de l'arginine (NOS et ARG). L'apport d'ALA (11%) augmente le pool hépatique du glutathion, alors que les plus forts apports d'ALA (42%) modulent l'expression des principales enzymes impliquées dans les voies d'utilisation de la cystéine (γGCL et CDO). Le PPARα ne semble pas être directement impliqué dans les effets observés de l'ALA, néanmoins, l'invalidation du PPARα rend le métabolisme secondaire des acides aminés plus sensible à la nature des acides gras alimentaire. Une meilleure biodisponibilité du NO et du glutathion suite à l'apport alimentaire d'ALA serait bénéfique pour la physiopathologie du syndrome métabolique. Il semble donc intéressant, à l'issus de ce travail, d'élaborer des études nutritionnelles validant ces effets de l'ALA chez l'homme dans une perspective de recommandations nutritionnelles.

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33

Pratoomyot, Jarunan. "Investigating alternative raw materials and diet formulations on growth performance, lipid metabolism and gene expression in Atlantic salmon (Salmo salar L.)." Thesis, University of Stirling, 2010. http://hdl.handle.net/1893/2408.

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Fish meal (FM) and fish oil (FO) have traditionally been central in aquaculture feed formulation but the finite global supply situation limiting future use along with issues of contaminant levels in these feed ingredients have become critical issues. The objectives of the present study were to investigate alternative feed ingredients as substitutes for both FM and FO in feeds for Atlantic salmon (Salmo salar) to ensure optimal growth, feed efficiency and health of the fish as well as maintaining the nutritional quality of the fish product to the human consumer, especially the levels of n-3 highly unsaturated fatty acid (HUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in the flesh. The results of the present study revealed that there were no negative effects on growth performance, feed utilisation and apparent digestibility in Atlantic salmon when FO was substituted with vegetable oil (VO) but these parameters were affected when FM was replaced with alternative protein sources from plants and animals at high levels, despite dietary supplementation with crystalline amino acids and lecithin. Reduction in feed intake was a factor affecting growth retardation when FM inclusion decreased. However, replacing FM with alternative plant and animal proteins along with partial replacement of FO had no major effect on nutritional quality, particularly n-3 HUFA content of salmon tissues. Replacing Northern FO with decontaminated FO or blends of southern hemisphere FO and VOs strategies to reduce POP contaminants and retain high nutritional values in flesh were very successful. Dietary treatments and genetic origin of fish both had effects on tissue compositions and gene expression. All fish groups (strain/family), consist of CAL, LEAN and FAT strains, fed a diet containing VO showed significant differential expression of lipid metabolism-related genes compared to fish fed a FO diet with LEAN strain appearing to adapt to VO inclusion better than FAT strain. This thesis has demonstrated dual replacement of FM and FO with alternative raw materials in salmon feeds without a major negative impact on nutritional quality.

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34

Wilson, Gillian Mary. "Fatty acids in human colonic mucosa." Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316584.

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Lalia, Antigoni. "Omega-3 fatty acids to combat sarcopenia." Thesis, College of Medicine - Mayo Clinic, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10124986.

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Background: Age-related sarcopenia leads to frailty, physical disability and loss of independence. Although exercise is an effective strategy to counteract the prevailing loss of muscle mass, older adults exhibit blunted anabolic responses, and are often unable to adopt an active lifestyle due to comorbidities associated with aging. Long chain polyunsaturated fatty acids (n-3 PUFA), eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid, are non-pharmaceutical nutrients which have surfaced for their potential anabolic properties on skeletal muscle and may be particularly beneficial in the context of sarcopenia.

Objective: First, to determine if EPA and DHA increase muscle protein synthesis in older adults. Second, to determine if n-3 PUFA increase the anabolic response to an acute resistance exercise stimulus in older adults. Third, to assess if their effect is mediated through improved mitochondrial function, which is known to be impaired with aging.

Methods: Twelve old, sedentary, healthy women and men (65-85 years) were given 3.9 grams/day purified EPA/DHA for 4 months. 12 young adults (18-35 years) were included as a comparison group for baseline measurements. Muscle protein fractional synthesis rate (FSR) was measured before and after treatment for mixed muscle, and subcellular fractions of myofibrillar, mitochondrial and sarcoplasmic proteins. We infused a stable isotope tracer of [ring-¹³C₆] phenylalanine and monitored incorporation of the amino acid into muscle proteins, at the fasting, post absorptive state, and 16 hours following an acute bout of unaccustomed resistance exercise, using mass spectrometry. Muscle mitochondrial function was assessed ex vivo from skeletal muscle biopsies. Further mechanistic information was generated through large scale and individual mRNA gene expression, inflammatory markers, and protein phosphorylation signaling of the anabolic pathway.

Results: Protein synthesis was similar between age groups at baseline and post exercise, despite the robust decline in mRNA gene expression with aging. EPA/DHA supplementation increased total lean mass, and increased mitochondrial and sarcoplasmic FSR at baseline. Following acute exercise, mixed muscle and subcellular FSR did not change significantly, but participants were segregated into responders and non-responders. EPA/DHA further potentiated the anabolic response of mitochondrial FSR to levels greater than that in the young. There was no improvement in mitochondrial oxidative capacity and efficiency, but there was a significant decrease in ROS emissions.

Conclusion: In healthy older adults, EPA/DHA exhibited significant anabolic effect in baseline skeletal muscle mitochondrial and sarcoplasmic FSR, which was dissociated from mitochondrial oxidative capacity. The anabolic response to exercise was variable between responders and non-responders where some individuals presented with marked increase in mixed muscle and subcellular FSR. This observation sets the ground for identifying the phenotypic traits of the elderly who are likely to benefit from the therapeutic use of n-3 PUFA to combat sarcopenia of aging.

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Ribeiro, Beatriz Gonçalves. "Efeito comparativo de repositores energéticos sobre as concentrações plasmáticas de glicose e ácidos graxos livres de corredores de longa distância." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/89/89131/tde-14112012-091911/.

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A reposição de glicogênio pós treino foi investigada usando uma mistura de ambos, glicose e glicose-frutose, como repositores, em atletas corredores de longa distância. Dez corredores competitivos (30±4,7 anos) foram avaliados para composição corporal e consumo alimentar antes do exercício de 90 minutos em esteira elétrica a 70% V02máx. Amostras de sangue venoso foram coletadas antes e após o término do exercício, quando eles receberam 1g de carboidrato.kg-1 de uma mistura de ambos, glicose-frutose (CHO1) e glicose (CHO2), e outra com sucralose ou placebo (controle). Amostras de sangue foram retiradas 30, 60, 90 e 120 minutos após o consumo dos suplementos e usadas para determinação de glicose e de ácidos graxos plasmáticos, por reações colorimétricas. Não foram observadas diferenças significativas na composição corporal e na hidratação durante o exercício. Os tratamentos CHO1 e CHO2 produziram elevação na glicemia, em 30 minutos, comparados ao grupo placebo. Entretanto, em 90 min, somente no tratamento CHO1, uma queda na glicemia foi observada (CHO2>CHO1). Os ácidos graxos livres aumentaram comparativamente após o exercício (CHO1=CHO2=placebo) e, diferente do placebo, em 90 minutos, reduziram nos tratamentos CHO1 e CHO2. Ambos os repositores atuaram similarmente nas concentrações de ácidos graxos livres, mas o declínio da glicose plasmática (remoção da glicose) ocorreu primeiramente com o tratamento glicose-frutose do que com o glicose. Assim, a mistura glicose-frutose parece promover uma reposição de glicogênio mais rápida após exercícios de longa duração.
The post training glycogen replacement was investigated using either glucose or glucose-fructose mixture as repositors in long-distance athletes. Ten males (30±4,7yrs) voluntary competitive long distance runners were assessed for body composition and dietary intake prior to a 90 min 70% vo2 max exercise in treadmill. Blood samples were collected before and after the exercise when they received orally 1g of CHO.kg-1 either as maltodextrin-glucose-fructose (CHO1) or maltodextrin - glucose (CHO2) mixtures, having sucralose or placebo (control). Blood samples were drawn 30,60, 90 and 120 minutes after supplement intake and used for plasma glucose and free-fatty acids determinations by colorimetric reactions. There were no significant changes on body composition, mass or hydration, during the treadmill exercise. CHO1 and CHO2 loading increased the 30 min blood glucose both significatively above the placebo. However at 90 min only CHO1 decreased significantily (CHO2>CHO1). The FFA increased comparatively (CHO1=CHO2=placebo) after exercise and differently from placebo CHO1 and CHO2 decreased (similarly) up to 90 min. Both energetic repositors acted similarly on FFA levels but the plasma glucose decreasing (glucose removal) occurred earlier with glucose-fructose loading rather than glucose alone. Thus glucose-fructose mixtures seems to promote faster glycogen repletion after long lasting aerobic exercises.

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De, Wet Martie. "The effect of colonic propionate and the acetate : propionate ratio on risk markers for cardiovascular disease in westernised African men." Thesis, Bloemfontein : Central University of Technology, Free State, 2009. http://hdl.handle.net/11462/30.

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38

O'Shea, Karen Michelle. "Omega-3 Fatty Acids and Heart Failure." Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1258128805.

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Baker, Nancy Carol. "The Associations Among Dietary Fatty Acids, Plasma Fatty Acids, and Clinical Markers in Postmenopausal Women with Diabetes." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1253666943.

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40

Makarem, Nour. "Dietary intake of polyunsaturated fatty acids in relation to red blood cell membrane fatty acids and bone health in healthy men: a cross-sectional study." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=103742.

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Polyunsaturated fatty acids (PUFA) and long chain PUFA (LCPUFA) may play a role in bone health, but evidence is scarce in human males. The objective of this study is to determine if the dietary intake of PUFA and LCPUFA, particularly the omega-3 LCPUFA, and their subsequent levels in red blood cell (RBC) membranes are associated with higher bone mineral density (BMD) of the whole body, spine, hip, and femoral neck in healthy middle aged men. Anthropometric measurements, assessment of dietary and supplement intake, assessment of total and weight-bearing physical activity, quantification of total fatty acid levels in RBC membranes, and assessment of BMD using dual energy x-ray absorptiometry (DXA) was conducted in a cross-sectional sample of healthy middle-aged men. Statistical Analysis using the student t-test for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) intake and status above and below the median was conducted, followed by multiple linear regression analysis to confirm the results of the t-test while accounting for covariates including body mass index (BMI), serum 25-hydroxy vitamin D (25(OH)D), calcium intake, alcohol intake, and physical activity. Higher dietary intake of EPA+DHA was associated with higher whole body and spine BMD and spine z-score. Higher EPA intake was associated with higher spine z-score. Finally, higher EPA status (% in RBC) was associated with higher whole body and spine BMD; and of femoral neck and spine z‐scores. These preliminary results suggest that men with higher intakes of EPA and DHA and higher EPA status have improved bone health. However, it appears the LCPUFA status is a stronger predictor than dietary LCPUFA intake.
Les acides gras polyinsaturés (AGPI) et les acides gras polyinsaturés à longue chaîne (AGPI-LC) peuvent influencer la santé osseuse, mais très peu de preuves existent en ce qui concerne les hommes. L'objectif de cette étude est de déterminer si l'apport alimentaire en AGPI et en AGPI-LC, en particulier en oméga-3 AGPI-LC, et leurs concentrations subséquents dans les membranes des érythrocytes sont associés à une plus grande densité minéral osseuse (DMO) du corps entier, de la colonne vertébrale, des hanches et du col du fémur chez les hommes d'âge moyen en bonne santé. Dans un échantillon transversal d'hommes d'âge moyen en bonne santé, les mesures anthropométriques ont été relevées, l'apport des aliments et des suppléments alimentaires ainsi que les activités physiques totales et celles avec mise en charge évalués, les concentrations totales des acides gras dans les membranes des érythrocytes quantifiées et les DMO mesurées par ostéodensitométrie. L'analyse statistique a été effectuée à la fois pour l'apport et le bilan en acide eicosapentanoique (EPA) et acide docosahexaenoique (DHA) au-dessus et en-dessous de la médiane en utilisant des tests-t de Student, suivi par une analyse de régression linéaire multiple pour confirmer les résultats des tests-t en prenant en compte les covariables. Un apport alimentaire plus élevé en EPA et DHA est associé avec des DMO plus élevées du corps entier et de la colonne vertébrale et un plus grand score-z pour la colonne vertébrale. Un apport plus élevé en EPA est associé avec un score-z réduit de celle-ci. Enfin, bilan plus élevé d'EPA (% présent dans les érythrocytes) est associé avec des DMO plus élevées du corps entier et de la colonne vertébrale et des plus grands score-z pour le col du fémur et la colonne vertébrale. Ces résultats préliminaires suggèrent que les hommes qui consomment plus d'EPA et de DHA et qui ont un bilan en EPA plus élevé ont une meilleure santé osseuse. Cependant, il semblerait que le bilan en AGPI-LC soit un meilleur indicateur que l'apport alimentaire en AGPI-LC.

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Veloza, Adriana J. "Transfer of Essential Fatty Acids by Marine Plankton." W&M ScholarWorks, 2005. http://www.vims.edu/library/Theses/Veloza05.pdf.

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42

AlSaleh, Saja. "Relationship between breast milk fatty acids and infant bone mass and metabolism." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=106517.

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The primary objective of this thesis was to determine if long chain polyunsaturated fatty acids (LCPUFA) in maternal milk relates to infant bone mineral content, density and metabolism. A cohort of healthy singleton breastfed infants (n=120) were studied at 1 month post-partum. The measurements included anthropometric measurements of both mother and infant. Maternal dietary intake was assessed using both a 24-h recall and a food frequency questionnaire. A representative breast milk sample was collected for measurement of LCPUFA. Infant bone mineral content and density were assessed using dual-energy x-ray absorptiometry along with plasma parathyroid hormone, 25-hydroxyvitamin D and ionized calcium, plus urinary calcium:creatinine. Infant size at birth and 1 mo were within 2 SD of the World Health Organization growth standard. Maternal intake of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) during pregnancy (r = 0.42, p<0.0001; r = 0.46, p<0.0001; respectively) directly associated with milk LCPUFA composition. Maternal intake of DHA and EPA the day before showed similar results (r = 0.43, p<0.0001; r = 0.51, p<0.0001; respectively). Correlation analysis revealed a negative correlation between breast milk DHA and arachidonic acid (AA) with the infant lumbar spine vertebrate 1-4 bone mineral content (BMC) (r = - 0.18, p = 0.05; r = - 0.19, p = 0.04; respectively) but these relationships were not evident in multivariate analyses. In multivariate analysis, adjusted for infants' weight, age, gender, ethnicity, vitamin D supplementation and maternal smoking and pre-pregnancy body mass index (BMI), breast milk LCPUFA was not related to infant bone mineral density (BMD) nor BMC. Based on the multivariate analysis, breast milk LCPUFA do not explain the variance in bone mass early post-natally. However, since dietary intake may not reflect LCPUFA status, further studies are warranted using measures of infant LCPUFA status along with bone mass to confirm these observations.
L'objectif principal de cette thèse était de déterminer si longue chaîne d'acides gras polyinsaturés (AGPI-LC) dans le lait maternel se rapporte à la teneur en minéraux des os du nourrisson, la densité et le métabolisme. Une cohorte de santé Singleton nourrissons allaités (n = 120) ont été étudiés à 1 mois post-partum. Les mesures comprenaient des mesures anthropométriques de la mère et du nourrisson. Maternelle apport alimentaire a été évaluée en utilisant à la fois un rappel de 24 h et un questionnaire de fréquence alimentaire. Un échantillon de lait maternel représentatifs ont été recueillis pour la mesure de AGPILC. Le contenu minéral osseux et la densité du nourrisson ont été évaluées en utilisant la bi-énergie absorptiométrie à rayons X avec l'hormone parathyroïdienne plasma, 25-hydroxyvitamine D et le calcium ionisé, plus de calcium urinaire: créatinine. La taille du nourrisson à la naissance et 1 mois étaient à moins de 2 SD de la norme de croissance mondiale de la Santé Organisation. Apport de la mère de l'acide docosahexaénoïque (DHA) et l'acide eicosapentaénoïque (EPA) pendant la grossesse (r = 0,42, p <0,0001, r = 0,46, p <0,0001; respectivement) directement associés avec le lait AGPILC composition. Apport de la mère de DHA et d'EPA la veille a montré des résultats similaires (r = 0,43, p <0,0001, r = 0,51, p <0,0001; respectivement). L'analyse de corrélation a révélé une corrélation négative entre le lait maternel DHA et acide arachidonique (AA) avec la colonne vertébrale lombaire infantile vertébrés 1-4 contenu minéral osseux (CMO) (r = - 0,18, p = 0,05, r = - 0,19, p = 0,04; respectivement), mais ces relations ne sont pas évidentes dans les analyses multivariées. En analyse multivariée, ajustée pour le poids des nourrissons, âge, sexe, origine ethnique, supplémentation en vitamine D et le tabagisme maternel et pré-grossesse indice de masse corporelle (IMC), le lait maternel AGPILC n'était pas liée à la densité minérale osseuse du nourrisson (DMO), ni BMC. Basé sur l'analyse multivariée, le lait maternel AGPILC n'expliquent pas la variance de la masse osseuse précoce post-natale. Toutefois, depuis l'apport alimentaire peut ne pas refléter l'état AGPILC, nouvelles études sont justifiées par des mesures d'AGPILC état infantile ainsi que la masse osseuse pour confirmer ces observations.

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43

Onibi, Gbenga Emmanuel. "Influence of dietary fatty acids and α-tocopherol on muscle tissue quality." Thesis, University of Aberdeen, 1997. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU551786.

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Three experiments, two with pigs and one with Atlantic salmon, (Salmo salar) were carried out to investigate the effects of dietary supplementation with α-tocopheryl acetate (ATA) on quality of pig and salmon tissues. In Experiment 1, 32 pigs were individually fed either of two dietary fat sources: 0.5:0.5 w/w coconut oil/lard (59 g/kg finisher diet) or rapeseed oil (100 g/kg finisher diet) (as contained in full-fat rapeseed {FFR}), with or without supplementary ATA at 200 mg/kg diet. In Experiment 2, 24 pigs were individually fed either a diet which contained mixtures of vegetable oil (59 g/kg diet) (having a high level of palm oil) or rapeseed oil diet as in Experiment 1. The rapeseed oil diets were supplemented with 0, 200 and 500 mg ATA/kg diet. In Experiment 3, a commercial diet with high lipid content (290 g/kg diet) and 250 mg ATA/kg diet was supplemented with 0, 400 and 700 mg ATA/kg diet. Diets were fed to 54 salmon. Tissue samples were stored at 4°C and/or -20°C for different periods. Spectral data on tissue samples were collected with an NIRSystems 6500 scanning monochromator. Salmon and pig tissues, and pig muscle subcellular fractions (microsomal and mitochondrial) were analysed for fatty acid composition, α-tocopherol (AT) content and oxidative stability (by thiobarbituric acid test). In both pigs and salmon, muscle drip loss was measured, and the colour score and carotenoid content of salmon fillets were determined. Data presented in this study indicate that pig tissues respond positively to increased dietary supply of unsaturated fatty acids (UFA). Pig tissue UFA and n-3 fatty acid contents were increased, and n-6/n-3 fatty acid ratio was decreased by feeding diets containing FFR. There was only a slight influence of dietary fatty acids on fatty acid composition of the subcellular membranes. AT concentration was higher in the mitochondrial fraction than the microsomal fraction. The mitochondrial fraction lipids had a higher content of UFA than those of the mcirosomal fraction. Supplemental dietary ATA increased the AT content of both pig and salmon tissues.

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44

Sessions, Victoria A. "The effect of dietary fatty acids and cholesterol on lipoprotein metabolism in hamsters." Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385206.

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45

Ganesan, Balasubramanian. "Catabolism of Amino acids to Volatile Fatty Acids by Lactococcus lactis." DigitalCommons@USU, 2005. https://digitalcommons.usu.edu/etd/5509.

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Lactic acid bacteria are essential as flavor producers of cheese and fermented products. They are capable of catabolizing aromatic, branched chain, and sulfur amino acids to flavor compounds. During cheese ripening the numbers of lactococcal colonies decrease, but lactococci survive without replication in culture. This prompted an investigation into possible mechanisms of catabolism of branched chain amino acids into branched chain fatty acids and the physiological relevance of amino acid catabolism to the bacteria. We hypothesized that lactococci catabolize branched chain amino acids to branched chain fatty acids during nonculturability. Lactococci, lactobacilli, and brevibacteria catabolized both branched chain amino acids and keto acids into branched chain fatty acids. Lactococci survived carbohydrate-limited conditions for over 4 yrs. Their survival was represented by maintaining intracellular ATP, enzyme activity, membrane integrity, capability of ATP- and PMF-dependent substrate transport, transcription, and catabolism of amino acids to fatty acids. Assays conducted with NMR spectroscopy coupled with in silico analysis showed that branched chain substrates are catabolized via keto acids, HMG-CoA, and acetyl-CoA to branched chain fatty acids. A short list of candidate genes was identified for the pathway by gene expression analysis coupled to NMR analysis. The expression of these genes and the presence of the related catabolites were identified in long-term starved cultures of nonculturable lactococci. This verified that catabolism of branched chain amino acids to branched chain fatty acids occurred during the nonculturable state only and in conditions of carbohydrate deprivation. The pathway also facilitated fixation of carbon by lactococci, revealing the mechanism of survival of lactococci over 4 yrs in culture without the addition of external carbon sources. Between strains the availability of carbohydrate and acid stress played significant roles in modulating their ability to produce branched chain catabolites. The ability of lactococci to catabolize branched chain amino acids during sugar starvation represents a shift in carbon catabolic routes. The identified pathway also represented a balance between catabolism and anabolism, suggesting that the bacteria were in a homeostatic state during nonculturability. We accepted the hypothesis that nonculturable lactococci catabolized branched chain amino acids to branched chain fatty acids during starvation./p>

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Rauter, Yvonne. "The interaction of Staphylococcus aureus and human skin fatty acids." Thesis, University of Sheffield, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.556988.

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The human pathogen S. aureus is able to cause a large range of diseases, from minor skin diseases to life threatening sepsis. This versatility is governed by an extensive repertoire of virulence determinants and an acute ability to respond to the host environment in order to adapt, survive and proliferate. The problem of S. aureus is exacerbated by the rapid spread of antibiotic resistance, leading to such agents of public concern as methicillin resistant S. aureus (MRSA). There is therefore a desperate need to develop new therapeutic agents against S. aureus. Harnessing human innate defenses may provide a novel mechanism to combat the scourge of MRS A and other antibiotic resistant strains. Human skin fatty acids have been shown to have highly anti staphylococcal activity. In particular the major skin fatty acid cis-6-hexadecenoic acid (C-6-H) is able to rapidly kill S. aureus, by an unknown mechanism. Also C-6-H at concentrations, which do not kill the bacteria, is able to inhibit the production of major virulence determinants. This project aimed to determine the molecular response of S. aureus to C-6-H, a major facet of the human innate defence. Initial experiments showed that exposure to sub-MIC levels of C-6-H resulted in the induction of a resistance mechanism. In order to begin to determine the molecular basis for the induced resistance and the inhibition of virulence determinant production by C-6-H transcriptome and proteome studies were carried out. The transcriptome revealed an altered level of transcription of over 500 genes, in response to sub-MIC C-6-H, which are involved in virulence, amino acid biosynthesis, energy metabolism, stress response, purine and pyrimidine metabolism, cell wall and cell envelope dynamics and several regulatory systems. Interestingly, the expression of the toxins (hla, hlb, hlgBC) was highly reduced in the presence of C-6-H, whereas the expression of genes involved in host defence evasion (cap, sspAB, kalA) were increased. The proteome studies also showed a decrease in the production of several toxins. Members of the SaeRS regulon were reduced in expression, in response to C-6-H and several were confirmed by qRT-PCR. The use of specific mutants revealed the effect of C-6-H on toxin production is likely mediated directly or indirectly via SaeRS. The global effects ofC-6-H on S. aureus physiology are discussed.

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47

Virasith, Helene. "Long-chain polyunsaturated fatty acids and iron status in infants of gestational diabetic mothers." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86758.

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Arachidonic acid (AA), docosahexaenoic acid (DHA) and iron are important nutrients for infants and are hypothesized to be compromised in infants of diabetic mothers (IDM). The objective of this study was to compare AA, DHA and iron status in IDM with those measured in infants of non-diabetic mothers born both appropriate for gestational age (AGA) and large for gestational age (LGA); and to determine if infants that have compromised AA and DHA status also have a compromised iron status. Analyses of covariance between AA, DHA and iron revealed that AA in infants was positively correlated with iron status overall, but this was not the case for DHA. In IDM, the relationship between iron and AA status was more pronounced. These data suggest iron is linked to AA status in all infants and that IDM are at higher risk for low AA status and consequently impaired development.
L'acide arachidonique (AA), l'acide docosahexaénoïque (DHA) et le fer sont d'importants nutriments pour le nouveau-né. Il semblerait que leurs niveaux sont compromis chez les enfants de mères diabétiques (EMD). L'objectif de cette étude est de comparer les niveaux d'AA, de DHA et de fer chez les EMD avec ceux mesurés chez les enfants de mères non diabétiques qui sont nés avec un poids moyen ou gros pour l'âge gestationnelle pour déterminer si les niveaux de gras insaturés à longues chaînes et de fer sont tous les deux amoindris chez l'enfant. L'analyse de covariance entre le fer et les gras insaturés a montré que le niveau de fer est positivement corrélé avec le niveau d'AA mais pas avec celui de DHA. Chez les EDM, le lien entre le fer et l'AA est encore plus marquant. Ces résultats suggèrent que le niveau de fer est relié avec le niveau d'AA chez tous les nouveau-nés et qu'il y a un plus grand risque chez les EDM d'avoir un niveau d'AA amoindri et par conséquent de souffrir de problèmes de croissance.

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Borthakur, Gayatri. "Dietary influences on the N-3 polyunsaturated fatty acids in blood and vascular lipids." Thesis, King's College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286236.

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Scholljegerdes, Eric J. "Amino acid and fatty acid nutrition of beef cattle consuming high-forage diets." Laramie, Wyo. : University of Wyoming, 2005. http://proquest.umi.com/pqdweb?did=888865061&sid=3&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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50

Bowman, Alan Stuart. "The role of dietary fat in increasing egg weight in the domestic hen (Gallus dometicus)." Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/23736.

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Dissertations / Theses on the topic 'Fatty acids in human nutrition'

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