Omega-3 polyunsaturated fatty acids (PUFA) and vitamin D both have anti-cancer effects through common and unique pathways. The hypothesis of this thesis is that the combination of n-3 PUFA with 1,25(OH)2D3 will inhibit breast cancer cell growth in an additive or synergistic manner. A 3X3 factorial design was used to test the combinations of five PUFA treatments (α-linoleic acid (ALA, 18:3n3), eicosapentaenoic acid (EPA, 20:5n3) and docosahexaenoic acid (DHA, 22:6n3), γ-linolenic acid (GLA, 18:3n6) and arachidonic acid (AA, 20:4n6)) with 1,25(OH)2D3 on MCF-7, MDA-MB-231, and MCF-10A cell growth, and determine any potential synergism in combination treatments. MCF-7 and MCF-10A cells responded to PUFA and 1,25(OH)2D3 treatments, but combinations provided no potential synergism. MDA-MB-231 growth was not affected by 1,25(OH)2D3, while combinations treatments involving ALA, EPA, GLA, and AA caused potentially synergistic growth inhibition. This thesis presents the novel observation that PUFA are sensitizing MDA-MB-231 cells to 1,25(OH)2D3 treatment.

Bioactive food components containing n-3 polyunsaturated fatty acids (PUFA) and curcumin modulate multiple determinants that link inflammation to cancer initiation and progression. In this dissertation, both transgenic and dietary mouse models were used to elucidate the effect of n-3 PUFA and curcumin treatment on murine intestinal inflammation. Specifically, fat-1 transgenic mice, which convert endogenous n-6 PUFA to n-3 PUFA in multiple tissues, exhibited a reduced number of colonic adenocarcinomas per mouse (1.05 plus/minus 0.29 versus 2.12 plus/minus 0.51, P = 0.033), elevated apoptosis (P = 0.03), and a decrease in n-6 PUFA–derived eicosanoids compared with wild-type (wt) mice in an azoxymethane (AOM) - dextran sodium sulfate (DSS) model. Following a 2-week recovery period after 5 days of DSS exposure, colonic inflammation and ulceration scores returned to pretreatment levels only in fat-1 mice. In addition, fat-1 vs wt mice exhibited decreased (P < 0.05) levels of CD3 , CD4 T helper, and macrophage cell numbers in the colon. The ability of n-3 PUFA to favorably modulate the resolution of intestinal inflammation in fat-1 mice was linked to an enhancement (P < 0.05) in the percentage of colonic lamina propria (cLP) CD4 FoxP3 cells and a decrease in both splenic and cLP Th17 cells (0.8 vs 1.2 percent in spleen, 1.4 vs 1.7 percent in colon) (P < 0.05) in fat-1 mice compared to wt. These results suggest that the antitumorigenic effect of n-3 PUFA may be mediated via its anti-inflammatory properties. The combined effect of n-3 PUFA and curcumin on DSS induced colitis was assessed in C57BL/6 mice. Addition of fish oil (FO) and/or curcumin to a corn oil (CO) based diet increased animal mortality compared to CO alone (P < 0.05). Consistently, following 1 or 2 cycles of DSS treatment, both dietary FO and curcumin promoted mucosal injury/ulceration compared to CO. However, compared to other diets, FO and curcumin combined feeding enhanced the resolution of chronic inflammation and suppressed (p < 0.05) a key inflammatory mediator, NF-kB, in colon mucosa. Mucosal microarray analysis revealed that dietary FO and curcumin differentially modulated the expression of genes induced by DSS treatment. These results suggest that dietary lipids and curcumin interact to regulate mucosal homeostasis and the resolution of chronic inflammation in the colon.

The thesis aims to evaluate the impact of aliment with higher contents of unsaturated fatty acids, consumed for a different period of time, to utilitarian attributes of pigs before a slaughter, with respect to the composition of fatty acids in the intramuscular fat of tested animals. The factors that influence the quality of meat are interior, exterior and technological. Among the qualitative markers of quality of meat we rank the share of meat and fat, acidification rate, color, viscosity, contents of intramuscular fat (marbling), smell, taste, juiciness and delicacy. Together with hygienic and nutritive attributes, consumers and processors consider these technological and sensory aspects to be the most important. The ultimate goal of this thesis is to compare the impact of different length of feeding soy oil on parameters of pork meat quality and growth. However, the interference of growth attributes was inconclusive and the test result came similar in different groups of tested pigs. What was influenced by adding the soy oil into the feed is the fatty acids profile. The contents of fatty acids remained unchanged in every test group. Over time the content of monounsaturated fatty acids decreased. The most significant change occurred in representation of polyunsaturated fatty acids, which increased in the test groups with longer period of feeding with enriched feed, mostly at the expense of monounsaturated fatty acids. The differences between the test groups of pigs were statistically inconclusive; therefore the soy oil enrichment did not worsen the technological parameters of meat and fat quality. The longer period of feeding the soy oil enriched feed led to significant increase in polyunsaturated fatty acids. According to the findings, adding the soy oil into the feed will have no effect at all if done short time before the slaughter.

The literature review summarizes characteristics of polyunsaturated fatty acids, problems of their metabolism, physiological effects and their occurrence in food. It pursues procedures and possibilities of fatty acids assessment with the help of gas chromatography. Experimental part of the thesis describes an assessment of fatty acids profile in fallow deer meat, roe deer and deer meat using the gas chromatography method operating the Fison 8000 series gas chromatograph as well as flame ionization detector. Conclusive differences in content of particular fatty acids and n-6/n-3 fatty acids ratio among single types of venison are being monitored by means of statistic processing. .

The Master's thesis deals with the effect of feed enrichment with various types of oils on the deposition of fatty acids in selected tissues. Forty male Wistar Albino rats were divided into four groups and fed for 10 weeks daily ad libitum with a basic feed mixture enriched with 8 % palm, 8 % safflower, 8 % fish oil or 8 % microalgae Schizochytrium sp. oil. Rats had also free access to the drinking water. Fat from the tissue samples (liver, muscle, visceral fat) was extracted, converted to methyl esters and analyzed with usage of gas chromatography. The results of the experiment show that the addition of various types of oils to the feed of model organism can influence the deposition of fatty acids in its tissues. The addition of fish oil and microalgae Schizochytrium sp. oil caused statistically significant decrease (p < 0,05) in the ratio of PUFA n-6/n-3 in all observed tissues to a value of 1 or less compared to the addition of palm and safflower oil. Low ratio of n-6/n-3 polyunsaturated fatty acids is considered to be more desirable in reducing the risk of cardiovascular diseases.

Dysregulation of adipokines in obese adipose tissue contributes to inflammation and insulin resistance. Fatty acids and lipopolysaccharide (LPS) can modulate adipokine secretion, however, less is known about their effects in combination. Long-chain n-3 polyunsaturated fatty acids (PUFA) exert anti-inflammatory effects and less is known about other n-3 and n-6 PUFA, which are more prevalent in the typical diet. Co-incubation of 3T3-L1 adipocytes with LPS and long-chain n-3 PUFA decreased LPS-induced secreted MCP-1 protein. n-6 PUFA arachidonic acid and LPS synergistically increased MCP-1 and IL-6 secreted proteins. Plant-derived PUFA were relatively neutral stimuli. mRNA expression results suggest potential roles for G protein-coupled receptor 120 and toll-like receptor 2 in mediating the effects of long-chain n-3 PUFA and arachidonic acid, respectively. Overall, this thesis suggests that both n-3 and n-6 PUFA are important factors to consider in the development of nutritional strategies for improving adipose tissue inflammation associated with obesity. / NSERC CGS, Ontario Graduate Scholarship

Background: Endothelial dysfunction is a major factor in the development of atherosclerosis, thrombosis and heart disease. Evidence suggests dietary fat composition may modify cardiovascular risk, as well as surrogate markers of cardiovascular risk such as blood pressure, arterial stiffness and endothelium-dependent vasodilation. Aim: To investigate the impact of dietary fat composition on endothelial function and associated markers of vascular health. Methods: The effects of oils rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were separately investigated in a parallel-design, placebo-controlled randomised controlled trial (n=48, 6 weeks, 2.9 g/d), carried out in free-living healthy young men. Following a 2 week run-in period taking placebo capsules (olive oil), participants underwent baseline measurements of finger capillary density, endothelial progenitor cell numbers (EPC), platelet-monocyte aggregate numbers (PMA), ambulatory blood pressure (ABP), pulse wave analysis (PWA), digital volume pulse analysis (DVP), and gave blood samples for plasma lipid, glucose, insulin, nitric oxide metabolites (NOx) and isoprostanes. The same measurements were made at the study endpoint, 6 weeks. An in vitro investigation of the effects of physiologically-relevant fatty acid profiles on microvascular endothelial cell nitric oxide and prostacyclin production was also performed. Results: Neither EPA nor DHA supplementation influenced EPCs, capillary density, PMA, ABP, PWA, DVP or plasma cholesterol, triacylglycerol, glucose, insulin, NOx or isoprostanes compared to placebo. However, ambulatory night-time heart rate was increased following EPA supplementation compared to DHA. Furthermore, both EPA and DHA decreased plasma non-esterified fatty acids (NEFA) compared to placebo. The in vitro investigations suggested that the composition of circulating NEFA may differentially affect endothelial function in the microvasculature. Conclusion: Dietary EPA and DHA at relatively high doses do not improve a number of novel markers of vascular function, including microvascular function and a marker of endothelial repair in young healthy men. EPA and DHA have differing effects on heart rate during sleep, suggesting that further research is required into the possible adverse effects of higher doses of individual marine fatty acids in at-risk individuals. Further work is required to elucidate the role of physiological fatty acid profiles on endothelial function.

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

A series of experiments were conducted to explore factors affecting transfer of value-added ingredients from the diet to table eggs, with the goal of contributing to improvements in the enrichment process. Flaxseed-based ω-3 PUFA enrichment did not reduce lutein enrichment. The combine enrichment of lutein and ω-3 PUFA had decresed lipid oxidation potential. Also, when fed a ω-3 PUFA diet, birds scored as energetic Efficient had longer and wider villi, resulting in greater absorptive surface area/villi than Non-efficient hens. However, histomorphological differences did not affect transfer of ω-3 PUFA from diet to egg. Finally, birds fed graded levels of ω-3 PUFA to characterize change in lipid profile of egg and blood plasma in time reached a plateau in total ω-3 PUFA/egg in 5.9 to 6.6d, with High birds reaching the target of 300 mg/egg in 5d. Egg enrichment can be modulated by changes to the hen diet. / Animal Science

The aim of this research was to isolate and characterize novel strains of marine protists with potential to commercially produce PUFAs. Twelve trips were made visiting 10 different locations in the Canadian Maritime Provinces. Sixty-nine strains were isolated and screened for biomass and fatty acid production. Those meeting specific criteria were selected for further investigation including characterization by 18S rDNA sequencing. Isolate ONC-KTB-56 produced the greatest amount of biomass (1 807 mg L-1) and fatty acids (24.6% dry weight). Of the total fatty acids, ARA, EPA and DHA comprised 0.89, 1.22 and 4.7 percent, respectively. Isolate ONC-KTB-14 produced 1 704 mg L-1 dry biomass with 5.4 percent fatty acids including 1.44, 1.35 and 37.5 percent, ARA, EPA and DHA, respectively. Through optimization of culture conditions biomass, fatty acid content and the proportions of specific fatty acids can be increased. With such optimization, there is potential for isolates ONC-KTB-14 and ONC-KTB-56 to be grown at a commercial scale for production of PUFAs.