Dr Georg Lietz
- Email: email@example.com
- Telephone: +44 (0) 191 208 6893
- Address: School of Agriculture, Food and Rural Development (AFRD)
University of Newcastle
Newcastle upon Tyne NE1 7RU
My expertise lies in the area of human nutrition, with specific focus on fat soluble vitamins, fatty acids and related micronutrients. My group is known both nationally and internationally for our research on diet-gene interactions as an important factor in the determination of high inter-individual variations, as well as in determining total body stores of vitamin A by using the isotope dilution technique. Earlier on in my carreer, I was involved in the four centre FINGEN trial, the first UK based prospective genotyping study for the ApoE gene to investigate how n-3 fatty acids could influence cardiovascular disease risk depending on ApoE genotype. Following on from this, I was leading a research project within the European Nutrigenomics Organisation NUGO involving seven different European laboratories, which revealed through the application of genome-wide expression analysis, that β-carotene supplementation down-regulated genes affecting lipid and glucose metabolism related pathways. A milestone discovery in my research group was the discovery of novel single nucleotide polymorphisms in the beta-carotene monoxygenase (BCO1) gene. Recently, I initiated collaborations with colleagues in international nutrition (i.e. Prof. Keith West from John Hopkins University, Baltimore (US) and Dr. Marjorie Haskell from UC Davis, California (US)) to determine if a range of single nucleotide polymorphisms can influence the effectiveness of plant-based provitamin A carotenoids to increase vitamin A status in at-risk population groups.My research group has established the most sensitive and cost-effective method to analyse vitamin A status in humans. In collaboration with Prof. Mike Green from PennState University, we applied compartmental modelling to stable isotope derived data, which for the first time allowed to determine vitamin A status in individuals. Through our efforts to define the best practise of vitamin A total body store (TBS) determination, we were invited to lead an international study group which is evaluating the potential risk of vitamin A toxicity, currently funded by both the IAEA and the Gates Foundation. Our drive to develop a simpler and accurate method to measure vitamin A status in humans has informed on-going research to define new and simple approaches to determine vitamin A status in communities that suffer from both vitamin A deficiency and inflammation. We are in the process of developing new strategies for the assessment of vitamin A status in collaboration with the IAEA and the Gates Foundation. The overall outcome of this work will be the determination of safe upper levels of vitamin A intake to aid in the monitoring of vitamin A intervention regimens and thereby optimisation of the efficacy of vitamin A intervention programmes.
Roles and Responsibilities
Teaching undergraduate Nutrition students
Supervision of PhD students
Project lead PI for the Gates Foundation funded GlovitAs project
Member of the American Nutrition Society
Member of the Deutsche Gesellschaft für Ernährung
Member of the International Carotenoid Society
Member of the European Nutrition Leadership Programme Alumni Association
My group has gained an increasing international reputation with the development of collaborations with research partners in the US (John Hopkins University, UC Davis, PennState University, Case Western, Berkeley University), and Europe (INSERM; Wageningen University; University of the Balearic Islands; Kiel University; Freiburg University). We were the first to identify key genetic variants in the pro-vitamin A metabolism [Leung et al., 2009] in a BBSRC funded project. Securing funds to lead the European Carotenoid focus team within NUGO (The European Nutrigenomics Organisation), we were able to establish for the first time a link between beta-carotene and fat metabolism [Amengual et al., 2011]. We also developed the gold standard for the determination of vitamin A status in individuals in collaboration with Prof. Green [Green et al., 2016], resulting from a BBSRC project. More recently, I secured a $2M grant from the Bill and Melinda Gates Foundation, to lead a project involving international institutions from the Philippines, Bangladesh, Guatemala and the US. This project will enable our consortium to evaluate new strategies to detect novel biomarkers of vitamin A toxicity and to refine and verify the usefulness of the isotope dilution technique in children in community settings with high rates of inflammation. Thanks to the development of the isotope dilution technique, my research group is now working with the International Atomic Energy Agency (IAEA) in Vienna (Austria). We have also trained scientists from Wageningen University (The Netherlands) and the BATAN Institute in Jakarta (Indonesia) to use this technique.
Our funding comes from a range of funding bodies, including the Bill and Melinda Gates Foundation, the International Atomic Energy Agency (IAEA), BBSRC, and Industrial sponsorship from DSM.
Carotenoids/ Vitamin A
I have published book chapters with relevance for undergraduate and postgraduate teaching and contributed to a range of nutrition relevant courses offered at Newcastle University. I was the admissions tutor for the Food and Human Nutrition / Food Marketing and Nutrition Degree programme from 2013-15, during which time applications and registrations rose by 44% / 83% and 30% / 35%, respectively.
- Green MH, Ford JL, Green JB, Berry P, Boddy AV, Oxley A, Lietz G. A Retinol Isotope Dilution Equation Predicts Both Group and Individual Total Body Vitamin A Stores in Adults Based on Data from an Early Postdosing Blood Sample. Journal of Nutrition 2016, 146(10), 2137-2142.
- Tanumihardjo SA, Russell RM, Stephensen CB, Gannon BM, Craft NE, Haskell MJ, Lietz G, Schulze K, Raiten DJ. Biomarkers of Nutrition for Development (BOND)-Vitamin A Review. Journal of Nutrition 2016, 146(9), 1816-1848.
- Lietz G, Furr HC, Gannon BM, Green MH, Haskell M, Lopez-Teros V, Novotny JA, Palmer AC, Russell RM, Tanumihardjo SA, Van Loo-Bouwman CA. Current Capabilities and Limitations of Stable Isotope Techniques and Applied Mathematical Equations in Determining Whole-Body Vitamin A Status. Food and Nutrition Bulletin 2016, 37(2), S87-S103.
- Huebbe P, Lange J, Lietz G, Rimbach G. Dietary beta-carotene and lutein metabolism is modulated by the APOE genotype. BioFactors 2016, 42(4), 388-396.
- Bruins MJ, Kupka R, Zimmermann MB, Lietz G, Engle-Stone R, Kraemer K. Maximizing the benefits and minimizing the risks of intervention programs to address micronutrient malnutrition: symposium report. Maternal and Child Nutrition 2016, 12(4), 940-948.
- Green MH, Ford JL, Oxley A, Green JB, Park H, Berry P, Boddy AV, Lietz G. Plasma Retinol Kinetics and β-Carotene Bioefficacy Are Quantified by Model-Based Compartmental Analysis in Healthy Young Adults with Low Vitamin A Stores. Journal of Nutrition 2016, 146(10), 2129-2136.
- Mberama CHH, Lietz G, Kyriazakis I. The effects of gender and muscle type on the mRNA levels of the calpain proteolytic system and beef tenderness during post-mortem aging. Livestock Science 2016, 185, 123-130.
- Lietz G, Oxley A, Ford J, Green M. A modified isotope dilution equation predicts vitamin A total body stores in individuals. In: Experimental Biology 2015. 2015, Boston, USA: Federation of American Societies for Experimental Biology.
- Lietz G, Oxley A, Berry P, Hesketh J, Tourniaire F, Park H, Green M, Boddy A. β-carotene (BC) bioconversion is similar in men and women. In: Experimental Biology 2015. 2015, Boston, USA: Federation of American Societies for Experimental Biology.
- Oxley A, Warnke I, Wyss A, Schalch W, Lietz G. The BETASNP2 study: Effect of β-carotene formulation and rs6564851 on β-carotene plasma responses. In: Experimental Biology 2015. 2015, Boston, USA: Federation of American Societies for Experimental Biology.
- Lietz G, Haskell M, Melse-Boonstra A. Uncertainties of assessing total body vitamin A stores in community settings in low-income countries using the stable-isotope dilution methodology. American Journal of Clinical Nutrition 2015, 102(2), 520-521.
- Oxley A, Berry P, Taylor GA, Cowell J, Hall MJ, Hesketh J, Lietz G, Boddy AV. An LC/MS/MS method for stable isotope dilution studies of β-carotene bioavailability, bioconversion and vitamin A status in humans. Journal of Lipid Research 2014, 55(2), 319-328.
- Park H, Lietz G, Oxley A, Boddy A, Berry P, Wyss A, Schalch W, Green M. Simplified approaches for estimating vitamin A stores and beta-carotene bioconversion in humans. In: Mieconutrient Forum Global Conference. 2014, Addis Ababa, Ethiopia: Federation of American Societies for Experiemental Biology.
- Oxley A, Berry P, Hall MJ, Cowell J, Hesketh J, Lietz G, Boddy AV. An LC-MS/MS Method for Stable Isotope Dilution Studies of β-Carotene Bioavailability, Bioconversion and Vitamin A Status in Humans. In: European Journal of Ophthalmology. 2013, Cambridge, UK: Wichtig Publishing.
- Oxley A, Berry P, Cowell J, Hall M, Hesketh J, Lietz G, Boddy AV. An LC-MS/MS method for stable isotope dilution studies of β-carotene bioefficacy and vitamin A status in humans. In: Nutrition Society Annual Summer Meeting. 2013, Newcastle upon Tyne, UK: Cambridge University Press.
- Borel P, Lietz G, Goncalves A, de Edelenyi FS, Lecompte S, Curtis P, Goumidi L, Caslake MJ, Miles EA, Packard C, Calder PC, Mathers JC, Minihane AM, Tourniaire F, Kesse-Guyot E, Galan P, Hercberg S, Breidenassel C, Gross MG, Moussa M, Meirhaeghe A, Reboul E. CD36 and SR-BI Are Involved in Cellular Uptake of Provitamin A Carotenoids by Caco-2 and HEK Cells, and Some of Their Genetic Variants Are Associated with Plasma Concentrations of These Micronutrients in Humans. Journal of Nutrition 2013, 143(4), 448-456.
- Lietz G, Oxley A, Bosch-Saadatmandi C. Consequences of common genetic variations on beta-carotene cleavage for vitamin A supply. In: Sommerburg, O; Siems, W; Kraemer, K, ed. Carotenoids and Vitamin A in Translational Medicine. CRC Press, 2013, pp.383-396.
- Oxley A, Berry P, Hesketh J, Boddy AV, Lietz G. Gender differences in retinol metabolism are independent of β-carotene bioconversion. In: Nutrition Society Annual Summer Meeting. 2013, Newcastle upon Tyne, UK: Cambridge University Press.
- Asim M, Liu OH, Okello E, Birch-Machin M, Foltz M, Lietz G. The anti-oxidant capacity of green tea polyphenols in the oral cavity. In: Nutrition Society Annual Summer Meeting. 2013, Newcastle, UK: Cambridge University Press.
- Kofler BM, Miles EA, Curtis P, Armah CK, Tricon S, Grew J, Napper FL, Farrell L, Lietz G, Packard CJ, Caslake MJ, Mathers JC, Williams CM, Calder PC, Minihane AM. Apolipoprotein E genotype and the cardiovascular disease risk phenotype: Impact of sex and adiposity (the FINGEN study). Atherosclerosis 2012, 221(2), 467-470.
- Lietz G, Oxley A, Boesch-Saadatmandi C, Kobayashi D. Importance of b,b-carotene 15-15'-monooxygenase 1 (BCMO1) and b,b-carotene 9,10-dioxygenase 2 (BCDO2) in nutrition and health. Molecular Nutrition and Food Research 2012, 56(2), 241.
- Prathalingam N, Ferguson L, Young L, Lietz G, Oldershaw R, Healy L, Craig A, Lister H, Binaykia R, Sheth R, Murdoch A, Herbert M. Production and validation of a good manufacturing practice grade human fibroblast line for supporting human embryonic stem cell derivation and culture. Stem Cell Research and Therapy 2012, 3(2), 12.
- Lietz G, Oxley A, Leung W, Hesketh J. Single Nucleotide Polymorphisms Upstream from the β-Carotene 15,15'-Monoxygenase Gene Influence Provitamin A Conversion Efficiency in Female Volunteers. Journal of Nutrition 2012, 142(1), 161S-165S.
- Amengual J, Gouranton E, van Helden YGJ, Hessel S, Ribot J, Kramer E, Kiec-Wilk B, Razny U, Lietz G, Wyss A, Dembinska-Kiec A, Palou A, Keijer J, Landrier JF, Bonet ML, von Lintig J. Beta-Carotene Reduces Body Adiposity of Mice via BCMO1. PLoS One 2011, 6(6), e20644.
- van Helden YGJ, Godschalk RWL, von Lintig J, Lietz G, Landrier JF, Bonet ML, van Schooten FJ, Keijer J. Gene expression response of mouse lung, liver and white adipose tissue to beta-carotene supplementation, knockout of Bcmo1 and sex. Molecular Nutrition & Food Research 2011, 55(10), 1466-1474.
- Madden J, Williams CM, Calder PC, Lietz G, Miles EA, Cordell H, Mathers JC, Minihane AM. The Impact of Common Gene Variants on the Response of Biomarkers of Cardiovascular Disease (CVD) Risk to Increased Fish Oil Fatty Acids Intakes. In: Cousins, R.J., Bier, D.M., Bowman, B.A, ed. Annual Review of Nutrition. Palo Alto, California, USA: Annual Reviews, 2011, pp.203-234.
- Grune T, Lietz G, Palou A, Ross AC, Stahl W, Tang GW, Thurnham D, Yin SA, Biesalski HK. beta-Carotene Is an Important Vitamin A Source for Human. Journal of Nutrition 2010, 140(12), 2268S-2285S.
- van Helden YGJ, Heil SG, van Schooten FJ, Kramer E, Hessel S, Amengual J, Ribot J, Teerds K, Wyss A, Lietz G, Bonet ML, von Lintig J, Godschalk RWL, Keijer J. Knockout of the Bcmo1 gene results in an inflammatory response in female lung, which is suppressed by dietary beta-carotene. Cellular and Molecular Life Sciences 2010, 67(12), 2039-2056.
- Lietz G, Lange J, Rimbach G. Molecular and dietary regulation of beta,beta-carotene 15,15'-monooxygenase 1 (BCMO1). Archives of Biochemistry and Biophysics 2010, 502(1), 8-16.
- van Ommen B, El-Sohemy A, Hesketh J, Kaput J, Fenech M, Evelo CT, McArdle HJ, Bouwman J, Lietz G, Mathers JC, Fairweather-Tait S, van Kranen H, Elliott R, Wopereis S, Ferguson LR, Meplan C, Perozzi G, Allen L, Rivero D, Micronutrient Genomics Project Wor. The Micronutrient Genomics Project: a community-driven knowledge base for micronutrient research. Genes & Nutrition 2010, 5(4), 285-296.
- Hesketh JE, Lietz G. A network approach to micronutrient genetics: interactions with lipid metabolism. Current Opinion in Lipidology 2009, 20(2), 112-120.
- Tourniaire F, Gouranton E, von Lintig J, Keijer J, Bonet ML, Amengual J, Lietz G, Landrier JF. β-carotene conversion products and their effects on adipose tissue. Genes and Nutrition 2009, 4(3), 179–187.
- Leung WC, Hessel S, Méplan C, Flint J, Oberhauser V, Tourniaire F, Hesketh JE, von Lintig J, Lietz G. Two common single nucleotide polymorphisms in the gene encoding β-carotene 15,15′-monoxygenase alter β-carotene metabolism in female volunteers. FASEB Journal 2009, 23(4), 1041-1053.
- Caslake MJ, Miles EA, Kofler BM, Lietz G, Curtis P, Armah CK, Kimber AC, Grew JP, Farrell L, Stannard J, Napper FL, Sala-Vila A, West AL, Mathers JC, Packard C, Williams CM, Calder PC, Minihane AM. Effect of sex and genotype on cardiovascular biomarker response to fish oils: the FINGEN Study. American Journal of Clinical Nutrition 2008, 88(3), 618-629.
- Williams CM, Ordovas JM, Lairon D, Hesketh J, Lietz G, Gibney M, Ommen B. The challenges for molecular nutrition research 1: Linking genotype to healthy nutrition. Genes and Nutrition 2008, 3(2), 41-49.
- Bergmann MM, Bodzioch M, Bonet ML, Defoort C, Lietz G, Mathers JC. Bioethics in human nutrigenomics research: European Nutrigenomics Organisation workshop report. British Journal of Nutrition 2006, 95(5), 1024-1027.
- Lietz G, Mulokozi G, Henry JCK, Tomkins AM. Xanthophyll and hydrocarbon carotenoid patterns differ in plasma and breast milk of women supplemented with red palm oil during pregnancy and lactation. Journal of Nutrition 2006, 136(7), 1821-1827.