GENE-NUTRIENT INTERACTIONS

GENE-NUTRIENT INTERACTIONS

Gene-nutrient interactions are studied as nutritional genomics or nutrigenomics.  They are important in preventing and treating diseases.   A range of dietary chemicals, sale which are bioactive, influence the expression of genetic information and therefore influence our health, can theoretically prevent diseases and even have an impact in treatment of chronic diseases.[1],[2],[3]  Explained by Törrönen et al:  “Nutritional genomics, or nutrigenomics, is the study of how food and genes interact and aims to understand the effects of diet on an individual’s genes and health. It attempts to study the genome- wide influences of nutrition and identify the genes that influence the risk of diet-related diseases on agenome-wide scale, and to understand the mechanisms that underlie these genetic predispositions.”[4]

EXAMPLES of Gene-Nutrient Interactions

ApoE genotypes

There is strong evidence on relationship of apoE genotypes with LDL-C levels and coronary risk.  In an updated meta-analysis by Bennet et al[5] the relationship between apoE genotypes, coronary risk and circulating lipid level is reviewed.  Subjects with genotype ?3/?3 are at higher risk compared with ?2/?2 (20% less risk) and ?4/?4 only a slightly increased risk.  According to this, apoE4 carriers do respond better on low fat diet.  Majority of cases of Alzheimer´s disease reveal common late onset influenced both by environmental and genetic risk factors, genetic risk factor demonstrating ?4 allele being present in the apoE gene.  Explained by Bu[6]; “Mounting evidence demonstrate that apoE4 contributes to AD pathogenesis by modulating the metabolism and aggregation of amyloid-? peptide and by directly regulating brain lipid metabolism and synaptic functions through apoE receptors.”

MTHFR 677C®C Genotype

Individuals with MTHFR 677C®T genotype (aa change A222V) have raised plasma levels of homocysteine concentrations because of reduced enzyme activity.  This polymorphism is a genetic alteration leading to elevated homocysteine levels and lower folate levels, but not necessarily to increased risk of CHD.7  In a meta-analysis by Klerk et al[7], MTHFR 677CC genotypes are at less risk of CHD than MTHFR 677TT genotypes supporting the fact that low folate status alongside high homocysteine levels could be a causal factor for CHD occurrence.  There is a possible influence of small bias in this study as ethnic background is unequal between cases, e.g. the prevalence of the TT genotype is higher in white people versus black.[8]  According to the meta-analysis results show only positive association between the MTHFR 677 TT genotype and CHD risk when folate status is low noticing possible miscalculations because of different assays used.  Lewis et al[9] found no strong evidence in a meta-analysis on 80 studies (case-control and prospective) on MTHFR 677C®T variant and myocardial infarction and coronary artery occlusion or both in European, North American and Australian population.

HOMOCYSTEINE and Riboflavin

In a study by McNulty et al[10] gene-nutrient interaction is favored in relation to homocysteine and riboflavin.   According to this study, present findings have shown major impact on homocysteine levels from increasing riboflavin status e.g. from fortification, in individuals with TT genotype.  This could explain the differences in increased risk of neural tube defects between populations in TT genotypes.  CT genotype might have a weaker respond to riboflavin despite this study did not detect that.

HOMOCYSTEINE and Folic Acid

Using folic acid to lower raised homocysteine levels does not, according to Clarke[11], prevent cardiovascular diseases.  In a review by Clarke et al[12] on homocystene in relation to vascular diseases, findings reveal that lowering homcysteine does not prevent vascular disease in the general population.  Suggestions on renal impairment correlation as an underlying factor in vascular disease are put forward.

SELENIUM and Cancer

There is a growing body of evidence on low selenium status associated with increased risk of various types of cancer.  In a study by Hu et al[13] the relationship between selenium status and breast cancer is scrutinized.  According to the study there is a marked difference between Leu/Pro198 containing allele.  Leucine-containing allele is more frequently associated with breast cancer, Leu198 showing less response to selenium and needing higher selenium supplementation for cancer protection.  In a study by Cooper et al[14] on selenium and prostate cancer, men with SOD2-Ala16+ were at 19% increased risk compared with Val16 homozygotes.  There was 43% increased risk on all prostate cancer, 60% increased risk on advanced prostate cancer, 44% increased risk in “never smokers” and 97% increased risk in “ever smokers”.

GENE-NUTRIENT Interactions, Government Policy and the Future

According to the 2003 World Health Report[15], the leading cause of death in coming years will be of CVD, in the developing countries.  The WHO has declared obesity as a global epidemic with the information on more than one billion adults with BMI greater than 25, and about 300 million adults with BMI greater than 30. WHO has estimated that in the year 2030, the figure of 171 million people now suffering from type 2 diabetes, will be double.  WHO/FAO[16] has issued in a report evidences on obesity, hypertension and lipidaemia and how these risk factors can lead to coronary heart diseases, diabetes and stroke.  Nutrigenomics can be a useful tool to provide data for targeting specific policies, and can be used by policy planners and experts globally to treat and prevent chronic and complex diseases.[17]  In complex diseases high degree of heterogeneity in the pathophysiology are caused by multiple lifestyle and genetic factors.  Genetic make-up and environmental factors are both represented in chronic diseases and therefore, adding the relationship between genotype and diet to that is important when assessing disease risk and designing preventative actions.  Personalized nutritional recommendations based on genetic data could be a useful tool in that sense.[18]

CONCLUSION

Gene-nutrient interactions are important in treating and preventing complex diseases.  Our diet does influence the expression of genetic information and therefore influence our health.  Evidence on benefits from low cholesterol diet for CAD prevention, for ApoE e4-carriers, evidences for using riboflavin in reducing homocystene for TT genotypes as well as using folate.  It is a fact that chronic diseases are a growing problem globally and nutrienomics can be a useful tool for policy making and planning for preventative actions.

Copyright @ Jörth 2008-2017

REFERENCES

1 Kaput J, Perlina A, Hatipoglu B, Bartholomew A, Nikolsky Y. Nutrigenomics: concepts and applications to pharmacogenomics and clinical medicine. Pharmacogenomics 2007;8(4):369-90. [accessed 17 October 2012]. Available from: doi: 10.2217/14622416.8.4.369

2 Soloway PD. Gene nutrient interacions and evolution. Nutr Rev 2006;64(5):S52-S54. Available from: doi: 10.1301/nr.2006.may.S52-S54

3 Elliott R, Ong TJ. Nutritional genomics. BMJ 2002;324:1438-42. Available from: doi: 10.1136/bmj.324.7351.1438

4 Törrönen R, Kolehmainen M, Poutanen K. Nutrigenomics – new approaches for nutrition, food and health research. Food and Health Research Center, ETTK/Department of Clinical Nutrition. Kuopio, 20 November 2006.  Available from: http://kuopioinnovation.fi/sites/default/files/Nutrigenomiikkaraportti.pdf

5 Bennet AM, Angelantonio ED, Ye Z, Wensley F, Dahlin A, Ahlbom A, et al. Association of apolipoprotein E genotypes with Lipid levels and coronary risk. JAMA 2007;298(11):1300-1311. Available from: doi: 10.1001/jama.298.11.1300.

6 Bu G. Apolipoprotein E and its receptors in Alzheimer´s disease: pathways, pathogenesis and therapy. Nat Rev Neurosci 2009;10(5):333-334.  Available from: doi: 10.1038/nrn2620

7 Klerk M, Verhoef P, Clarke R, Blom HJ, Kok FJ, Schouten EG. MTHFR 677C®T polymorphism and risk of coronary heart disease. JAMA 2002;228(16):2023-2031. Available from: doi: 10.1001/jama.288.16.2023

8 Botto LD, Yang Q. 5,10-methylenetetrahydrofolate reductase gene variants and congenital anomalies: a HuGE review. Am J Epidemiol 2000;151:862-877.

9 Lewis SJ, Ebrahim S, Smith GD. Meta-analysis of MTHFR 677C®T polymorphism and coronary heart disease: does totality of evidence support causal role for homocysteine and preventive potential of folate? BMJ 2005;331:1053.  Available from: doi: 10.1136/bmj.38611.658947.55

10 McNultey H, Dowey LRC, Strain JJ, Dunne A, Ward M, Molloy AM et al. Riboflavin lowers homocysteine in individuals homozygous for the MTHFR 677C®T polymorphism. Circulation 2006;113:74-80. Avialable from: doi: 10.1161/CIRCULATIONAHA.105.580332

11 Clarke R. Homocystene, B vitamins, and the risk of cardiovascular disease. Chlin Chem 2011;57(8):1201-1202. Avialable from: doi: 10.1373/clinchem.2011.164855

12 Clarke R, Halsey J, Bennett D et al. Homocysteine and vascular disease: review of published results of the homocystene-lowering trials. J Inherit Metab Dis 2011;34(1):83-91. Available from: doi:10.1007/s10545-010-9235-y

13 Hu YJ, Diamond AM. Role of glutahione peroxidase 1 in breast cancer: loss of heterozygosity and allelic difference in the response to selenium. Cancer Res 2003;63:3347-3351. Available form: http://cancerres.aacrjournals.org/content/63/12/3347

14 Cooper ML, Adami HO, Gönberg H, Wiklund F, Green FR, Rayman MP. Interaction between single nucleotide polymophisms in selenoprotein P and mitochondrial superoxide dismutase determines prostate cancer risk. Cancer Res 2008;68:10171-10177. Avialable from: doi: 10.1158/0008-5472.CAN-08-1827

15 World Health Organization. The world health report 2003: shaping the future. Marketing and Dissemination. Geneva, Switzerland 2003.  Available from: http://www.who.int/whr/2003/en/whr03_en.pdf

16 World Health Oranization, Food and Agriculture Organization of the United Nations. Diet, nutrition and the prevention of chronic diseases. Joint WHO/FAO Expert Consultation on Diet, Nutrition and the Prevention of Chronic Disases, Geneva, Switzerland 2002. Who technical report series; 916. Available from: http://www.fao.org/docrep/005/AC911E/AC911E00.HTM

17 The NCMHD Ceneter of Exellence for Nutritional Genomics. Information – Concept in Nutrigenomics – Public And International Health. [internet] 2012. Available from: http://nutrigenomics.ucdavis.edu/?page=Information/Concepts_in_Nutrigenomics/Public_and_International_Health

18 Joost HG, Gibney MJ, Cashman KD, Görman U, Hesketh JE, Mueller M, et al. Personalised nutrition: status and perspectives. BJN 2007;98(01):26-31. Avialable from: doi: 10.1017/S0007114507685195

Copyright @ Jörth 2008-2017