NutrigenomicsSejal ParekhBiochem 118QDecember 2, 2010Doug BrutlagRoadmap•What is it?•What prompted it?•Goals•Tools•Methods•Example•Problems•Cartoons!What is it?•Using genomics tools to research effects of food on metabolism and gene expression•Working towards understanding–How regulation of homeostatic control is disturbed in a diet-related disease •Nutrigenetics – To what extent an individual’s genotypes influences metabolic pathways•(Müller & Sander, 2003)What prompted it?•More information via new research procedures–New technology–New Methods (GWAS)•Research began to indicate the importance of genetic predisposition–can be an important contributor to cardiovascular disease, diabetes type II, cancers–(Keating and Sanguinetti, 1996)•Nutrients began to be seen as contributing factorsWhat are the goals?•How nutrition influences metabolic pathways–Identification of transcription factors that function as nutrient sensors and the genes they target–Indicative biomarkers•Clinical diagnosis–Gene expression signatures•Clinical and research implications•the identification of genotypes that are risk-factors for the development of diet related diseasesMuller and Sander, 2003Methods•Outlook: Systems biology•Other fields–Genomics–Metabolomics – allows measuring of metabolites in blood or organs–Proteomics – study of proteins–Transcriptomics – study of RNA•Model organisms–Drosophila•adipose-like tissues & lipid transport system–transgenic and knockout mouse modelsTools•Tools–DNA microarray, •SNP arrays –Gel electrophoresis–Mass Spectrometry–Proton Nuclear Magnetic Resonance •MRI scansExample - Effect of Isoflavones on Breast & Prostate Cancer•Human studies seem to indicate a correlation between soy isoflavone consumption and protection towards breast and prostate cancers •Isoflavones – class of bioactive phytochemicals –potential role in the prevention of various chronic diseases•Mechanisms•Nutrigenetics –Individual variability in gut microflora composition and gene polymorphismsIsoflavones Mechanisms•Breast Cancer - Estrogen Receptors–Estrogens are mediated by the binding of one of the two specific nuclear receptors which can induce gene transcription of estrogen-responsive target genes•ERa and ERb–Estrogens acting via ERa exert strong proliferation stimulatory effects; those interacting with ERb tend to reduce this stimulation. •More ERa during tumour progression•Genistein correlated with downregulation of ERa and an upregulation of ERb mRNA and protein levels in breast cancer cells–A decrease in ERa protein expression in mammary tumours of rats after consumption of a soy extractIsoflavones Mechanisms•Prostate Cancer - Androgen Receptors–Genistein (isoflavone) exerts anti-androgenic effects and downregulates the expression and secretion of PSA–Numerous studies show a decrease in AR expression at mRNA and protein levels in prostate cells after exposure to isoflavone •Higher AR levels are correlated with higher risk or prostate cancer–Long-term soy protein consumption also lowered AR expression in prostate of men with high riskIsoflavone Gene Interaction•Known polymorphism–Phytoestrogen-gene interaction - CYP19 codes for the enzyme that catalyzes the irreversible conversion of androgens to estrogens. –4 known haplotypes, 1 haplotype with T, 3 with C–The T allele of the CYP19 3’UTR T-C polymorphism is associated with higher mRNA levels and thus higher enzyme activity•This enzyme catalyzes androgens to become estrogen•The TT genotype allows a specific nutrient-gene interaction which converts androgen receptors into estrogen receptors, decreasing the susceptibility to prostate cancerProblems and Roadblocks•Problems with Research–Control of intake•Diets are variable•Animal studies are more popular–Bioavailability•Uptake usually not measured–Critical to food studies–Biomarkers•Can’t rely on just one biomarker for a complex problem–Lack of knowledge of pathways•Lots of groundwork to be laid•Roadblocks in advancement–Funding–Ethical Issues•Who will have access to this information?–Business v. Public Knowledge•“Functional Foods” efficacy?•What sort of behavior does this encourage?Works Cited1. Berardi, John M. “Applied Nutrigenomics: Where Genes and Food Come Together.” January 09, 2008. www.t-nation.com/free_online_article/ sports_body_training_performance_nutrition/applied_nutrigenomics2. Cremouxa, Patricia de, Thisb, Pascale, Leclercqd, Guy, and Yves Jacquote. “Controversies concerning the use of phytoestrogens in menopause management: Bioavailability and metabolism.” Maturitas 65 (2010) 334–3393. Ham, Donhee and Westervelt, Robert M. “The Silicon that Moves and Feels Small Living Things.” Journal of Solid State Circuits. (October 2007) http://www.ieee.org/portal/pages/sscs/07 4. Keating, Mark T. and Sanguinetti, Michael C. “Molecular Genetic Insights Into Cardiovascular Disease” Science. Vol. 272, No. 5262 (May 3, 1996), pp. 681-685 5. Low, Yen-Ling, Taylor, James I., Grace, Philip B., Dowsett, Mitch, Folkerd, Elizabeth, Doody, Deborah, Dunning, Alison M., Scollen, Serena, Mulligan, Angela A., Welch, Ailsa A., Luben, Robert N., Khaw, Kay-Tee, Day, Nick E., Wareham, Nick J. and Sheila A. Bingham. “Polymorphisms in the CYP19 Gene May Affect the Positive Correlations between Serum and Urine Phytoestrogen Metabolites and Plasma Androgen Concentrations in Men.” J. Nutr. November 1, 2005 vol. 135 no. 11 2680-26866. Müller, Michael and Kersten, Sander. “Opinion: Nutrigenomics: goals and strategies.” Nature Reviews Genetics 4, 315-322 (April 2003) 7. Ruden, Douglas M., Luca, Maria De, Garfinkel, Mark D., Bynum, Kerry L. and Lu, Xiangyi. “Drosophila Nutrigenomics Can Provide Clues To Human Gene-Nutrient Interactions.” Annual Review of Nutrition. Vol. 25: 499-522 (July 2005) 8. Steiner, Claudia, Arnould, Stephanie, Scalbert, Augustin and Claudine Manach. “Isoflavones and the prevention of breast and prostate cancer: new perspectives opened by nutrigenomics.” British Journal of Nutrition (2008), 99, E-Suppl. 1, ES78–ES108 9. “Getting Rid Of Mice.” Must Know How. http://www.mustknowhow.com/index.php/home-and-garden/getting-rid-of-mice. Accessed Dec 01 2010 10. “What is Nutrigenomics?” Nutrigenomics Organisation. http://www.nugo.org/everyone/24023. Accessed Dec 01 201011.
View Full Document
Unlocking...