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Nutritional Genomics Nutrigenetics & Nutrigenomics. Professor Samar Kamal Kassim , H3ABioNet / H3Africa Co-Chair, Genomics Education and Coordinated Training Working Group (ECTWG), H3Africa Consortium Medical Biochemistry & Molecular Biology Department
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Nutritional GenomicsNutrigenetics & Nutrigenomics Professor Samar Kamal Kassim, H3ABioNet/H3Africa Co-Chair, Genomics Education and Coordinated Training Working Group (ECTWG), H3Africa Consortium Medical Biochemistry & Molecular Biology Department Faculty of Medicine, Ain Shams University
LearningObjectives • Understand relation between nutrition and genetics • Compare between Nutrigenomics and Nutrigenetics • Know what is meant by personalized Medicine • Know the Nurse’s role regarding nutritional personalization.
Nutritional Genomics van Ommen B. (2004) Nutrition 20:4-8.
Nutritional Genomics The study of how different foods can interact with particular genes to increase the risk of diseases such as type 2 diabetes, obesity, heart disease and some cancers http://nutrigenomics.ucdavis.edu/pressarticles.htm
Nutritional Genomics Nutrigenetics and nutrigenomics can be useful for better understanding of nutrient-gene interactions and development of “personalized nutrition” strategies for optimal health and disease prevention “Food and nutrition in 21st century”, Warsaw, 8-9.09.2011
Nutrigenomics • Nutrigenomicsanalyzes the effects of bioactive food components (nutrients and non-nutrients) on gene expression “Food and nutrition in 21st century”, Warsaw, 8-9.09.2011
Nutrigenetics • Nutrigenetics on the other hand identifies how the genetic makeup of a particular individual co-ordinates his or her response to various dietary nutrients. “Food and nutrition in 21st century”, Warsaw, 8-9.09.2011
Nutrigenomics • Nutrigenomicsseeks to examine these dietary signatures in specific cells, tissues and organisms and to understand how nutrition influences homeostasis. DIET Genotype Phenotype Health or Disease Food and nutrition in 21st century”, Warsaw, 8-9.09.2011
Nutrigenomics • Nutrigenomics aims also to identify the genes that influence the risk of diet-related diseases on a genome -wide scale and to understand the mechanisms that underlie these genetic predispositions. Food and nutrition in 21st century”, Warsaw, 8-9.09.2011
Nutrigenomics • A very simple example of Nutrigenomics is the effect of Glucose on gene expression. Food and nutrition in 21st century”, Warsaw, 8-9.09.2011
Nutrigenomics • Another example of Nutrigenomics is the effect of High Energy Diet on gene expression. Food and nutrition in 21st century”, Warsaw, 8-9.09.2011
Glucose • the most abundant monosaccharide in nature, provides a very good example of how organisms have developed regulatory mechanisms to cope with a fluctuating level of nutrient supply.
Glucose • In mammals the response to dietary glucose is complex because it combines effects related to glucose metabolism itself and effects secondary to glucose-dependent hormonal modifications, mainly pancreatic stimulation of insulin secretion and inhibition of glucagon secretion.
Glucose • In the pancreatic cells, glucose is the primary physiological stimulus for the regulation of insulin synthesis and secretion.
In the liver, glucose, in the presence of insulin, induces expression of genes encoding glucose transporters and glycolytic and lipogenic enzymes, and represses genes of the gluconeogenic pathway (glucose formation from non-carbohyrates).
Although insulin and glucagon were long known as critical in regulating gene expression, it is only recently that Glucose also have been shown to play a key role in Gene Expression.
Effect of High Energy Food on Gene Expression • Feeding high-energy diet to rats leads to early development of obesity and metabolic syndrome, apparently through an inability to cope with energy density of the diet.
Sickle Cell Anemia • Sickel cell anemia a “molecular disease” • Just one damaged molecule (genetic mutation) leads to a genetic disease.
Can Food Improve the Expression? • Intrauterine, fetal hemoglobin has high affinity to capture oxygen from the mother’s blood. • After birth, the genetic message for the production of this type of hemoglobin goes to sleep and is replaced by the message for the production of adult hemoglobin. • The fetal hemoglobin message is still on the genome; it is just not being expressed.
Can Food Improve the Expression? • Administering hydroxyurea or butyrate to an individual who carries the genetic message for the production of sickle hemoglobin awakens the message to produce the normal fetal hemoglobin that dilutes the sickle hemoglobin, preventing its aggregation. • This nutritional intervention is a classic example of the genetic nutritioneering approach.
Goal of NutriGenomics Use of personalized diets to prevent or delay the onset of disease and optimize and maintain human health http://nutrigenomics.ucdavis.edu/pressarticles.htm
Nutrigenetics • Nutrigenetics on the other hand identifies how the genetic makeup of a particular individual co-ordinates his or her response to various dietary nutrients. • It also reveals why and how people respond differently to the same nutrient (or drugs).
What is the evidence? • Single Gene Disorders • Phenyl Ketonuria
What is the evidence? • Single Gene Disorders • Lactose intolerance
Genetic variation between individuals results from numerous differences in nucleotide sequences within their genome: • single nucleotide polymorphisms (the most common form of genomic variation: in the human genome > 10 millions SNP) • copy number variations (CNV), deletions-insertions of single nucleotides or gene fragments, • substitutions and inversions.
“Personalized nutrition” A diet addressed to an individual and based upon her/his genotype, nutritional requirements and other factors (age and gender). It is expected that personalized nutrition will prevent diet-related chronic diseases. “Food and nutrition in 21st century”, Warsaw, 8-9.09.2011
“Role of Nurses” Transfer of Nutritional Genetic knowledge to the community and to her patients Help apply personalization of nutrition whenever possible and according to genetic analysis