chapter 6 Protein part 2

protein deficiency :

can have devastating affects high protein diet also harm -heart disease, cancer, osteoporsis, obesity , kidney stone

The human genome part 1

complete set of genetic material organized into 46 chromosomes located within the nucleus

Goal of nutritional genetics on heart disease

coordinate multiple finding on each of this risk factor, explaining the interaction among several gene and biological pathway and nutrients.

Low quality protein plants are

corn

nucleotides:

the subunits of DNA and RNA molecules, composed of a phosphate group, a 5-carbon sugar (deoxyribose for DNA and ribose for RNA), and a nitrogen-containing base.

completementary protein

this strategy yields complementary proteins that together contain all the essential amino acids in quantities sufficient to support health. The protein quality of the combination is greater than either food alone

The most common genetic difference involve a change in a nucleutide base located in the region of DNA strad -

thymine replacing cytosine and such variation are called SNP -- single nucleotide polymorphism

nutritiongenomics

which include epigenetics, examine how nutrient influence the activities of genes .

Heart disease

• Animal-protein intake also has sat. fat • Homocysteine levels associated risk • Arginine levels may be protective

Severe deficiency in kcals

• Frail, emaciated appearance • Weakened and appear apathetic • Many cannot stand without support • Look old • Hair is thin, dry, and dull • Body temperature and blood pressure are low • Prone to dehydration, infections, and unnecessary blood clotting

Marasmus -too few kcals

• Infancy, 6 to 18 months of age • Severe deprivation or impaired absorption of protein, energy, vitamins and minerals • Develops slowly • Severe weight loss and muscle wasting, including the heart • < 60% weight-for-age • Anxiety and apathy • Good appetite is possible • Hair and skin problems

select lean meat and poultry

-

What are chromosomes made up of

- DNA and associated proteins

How can the gene expression be determined

- can be determined by the measuring f the messenger RNA in the tissue sample -helps explain the development of disease and relationship between disease and relationship between diseases

Heart disease have both the effect of multi gene and environmental influences

- each risk factor for heart disease- multiple underlying genetic and environmental influences

nutrigenetics

- examines how genes influence the activities of nutrients

Genetic disease and variation

- genomic variation -- 1 percent -goal of nutritional genomics-- customize recommendation that fit individual need -explains why we are diff, why some of us get diseases and others does not

SNP and lipid metabolism

- lipid metabolism- reveals differences in a persons response to diet depending on wether the gene has a common SNP - people with the SNP have lower LDL when eating a diet rich in polyunsatured FA and higher lsl in low intake than those without the snp

lysine and tryptophan

- lysine may help with herpes, cold sore- research ineffective -tryptophan- relieve depression--- may be effective but caution is still adviced. can cause a rare blood disorder called to take tryptophan supplements developed a rare blood disorder known as eosinophilia- myalgia syndrome (EMS). EMS is characterized by severe muscle and joint pain, extremely high fever, and, in more than three dozen cases, death. Treatment for EMS usually involves physical therapy and low doses of corticosteroids to relieve symptoms temporarily.

AA supplement

- may be harmful - -increase doses cause diarrhea an excess of one AA can create a demand for carrrier that it limit the absorption of another AA, presenintg a possibility of deficiency -can create toxicity

The sequence of nucleotide bases (CGAT) determines

- the AA sequence of proteins. those bases are connected by hydrogen bonding to form base pairs adenine- thymine -guanine-cytosine

A gene is a segment of DNA that includes

- the information needed to synthesize one or more protein.

if the enzyme attach methyl group instead

- the protein is blocked from binding to the gene and the gene remain switched off

Epigenetics

- the study of heritable changes in a given function that occur without a change in the DNA sequence

What are the goal of scientists

- working on proteosome- hope to identify each protein made by the genes, the genes associated with aging and disease, dietary and life style choices that most influence the expression of genes

Kidney disease

-A high protein intake does not cause kidney disease, but it does increase the work of the kidneys.19 It may also accelerate kidney deterioration in people with chronic kidney disease. Restricting dietary protein may help to slow the progression of kidney disease in who have this condition.

A genomic primer

-DNA 46 chromosome , nucleotide bases

Genetic information is encoded in DNA molecules witthin the nucleus

-DNA molecule packed within the 46 chromosome

Multigene- disorder

-Several gene can influence the progression of a disease but no single gene causes the disease on its own -multi gene disorder often sensitive to interaction with the environmental influences

RDA and Adequate Energy

-The RDA covers the needs for replacing worn-out tissue, so it increases for larger people; it also covers the needs for building new tissue during growth, so it increases for infants, children, adolescents, and pregnant and lactating women. -Adequate energy- What happens when energy intake Falls short? 213

Adult Bone Loss (Osteoporosis)

-When protein intake is high, calcium excretion increases. Whether excess protein depletes the bones of their chief mineral may depend upon the ratio of calcium intake to protein intake. -bones need both protein and calcium. Some (but not all) research suggests that animal protein may be more detrimental to calcium metabolism and bone health than vegetable protein.

phenylketo-uria

-arises from mutation in the gene that codes for enzyme that converts essential AA phenylalanine to the AA tyrosine - without this enzyme- phenylalanine and its AA accumulate and damage the NS -at the same time, the body cannot make tyrosine or compounds made from it. consequently, tyrosine becomes an essential AA becasue the body cannot make it

Protein deficiency

-diet offers too little protein r lacks specific essential AA . -the synthesis of body protein decreases and the degradation increases to provide the need for AA -many activities come to halt.

nutritional genomics

-examines the interaction of genes and nutrient. these interactions include both nutrigenetics and nutrigenomics

• Read food labels • Current US and Canada intakes • Moderation

-food label- state quantity in grams, daily value for protein is not mandatory -people in united states get more protein then they need -The key diet-planning principle to emphasize for protein is moderation.Even though most people receive plenty of protein, some feel compelled to take supplements as well, as the next section describes.

Single gene disorder

-genetically predetermined usually exert their effects early in life and greatly affect those touched by them such diseases are rare. -the cause and effect of single gene disorder -clear -those with genetic defect get the disease and thsoe without donot

Homocystiene

-levels associated with increased risk ---including a diet high in saturated fatty acids—that can raise homocysteine in the blood or whether elevated levels are a cause or an effect of heart disease.9 Elevated homocysteine is associated with increased oxidative stress and inflammation. -coffee may increase the homocystiene level -

folate silence genes and protect against some cancer by providing

-methylation

Nutritonal genomics

-new field that examines how nutrient influnce gene activity and how genes influence the activities of nutrient

The effect of nutriion intervention in the PKU

-only current treatment - diet- restricts pheynlalanine and supplies the tyrosine to maintain blood level of these amino acid within the safe ranges -Diet restricted from protein pheynlalanine -if restricted diet is followed the symptoms can be prevented

Branched chain AA

-provide very little fuel and ordinary food provide them anyway. -Large dose of amino acid can raise the plasma ammonia concentration, which can be toxic to the brain . may be beneficial for liver disease patients .

SNP

-significant only if they affect AA seq of protein in a way that alters its function and if that function is critical to bodys well being.

symptoms

-slowed growth, impaired brain and kidney function, poor immunity and inadequate nutrient absorption ---> protein energy malfunction.

Simply having a certain gene does not determine that its associated trait will be expressed

-the gene has to be activated

Many nutrient and phytochemicals regulate gene expression and health through

-their involvement in the DNA methylation

protein qualities varies between food sources by 2 factors

1. Digestibility 2. AA composition - completeness

The double helical structures of DNA molecule is made up of

2 long chains of nucleotide -each nucleotide is composed of phosphate group, 5 carbon, sugar and base

DNA (deoxyribonucleic acid)

: the double helix molecules of which genes are made.

Heart disease

A high proteindiet may contribute to the progression of heart disease. As foods rich in animal protein also tend to be rich in saturated fats. Increased animal fat -- increased risk of Heart disease

How does amino acid composition affect protein quality

AA composition—Completeness • Essential amino acid consumption • Limiting amino acid the cell must have all the needed amino acid , the liver can make only nonessential amino acid if the essential amino acid are present. if the essential amino acid are not present the cell must break its own proteins. DIet of too little protein means- the protein sntheiss is limited

Human genome

All genetic information contained within a protein the complete set of genetic material (DNA) in a human being.

limiting amino amino acid

An essential amino acid supplied in less than the amount needed to support protein synthesis is called a limiting amino acid. : the essential amino acid found in the shortest supply relative to the amounts needed for protein synthesis in the body. Four amino acids are most likely to be limiting: • Lysine • Methionine • Threonine • Tryptophan

Adequate energy

An intake of 50 grams of protein provides 200 kcalories, which represents 10 percent of the total energy from protein, if the person receives 2000 kcalories a day. if the person cuts energy intake drastically—to, say, 800 kcalories a day—thenan intake of 200 kcalories from protein is suddenly 25 percent of the total; yet it's still the same amount of protein (number of grams) The protein intake is reasonable, but the energy intake is not. The low energy intake forces the body to use the protein to meet energy needs rather than to replace lost body protein.Similarly, if the person's energy intake is high—say, 4000 kcalories—the 50 g protein intake represents only 5 percent of the total; yet it still is a reasonable protein intake. Again, the energy intake is unreasonable for most people, but in this case, it permits the protein to be used to meet the body's needs.

CLinical concern

Changes in healthcare • Genetic predisposition to specific diseases • Development of 'designer' therapies • Creation of new medications for each genetic variation • Better understanding of nutrition's influence on biological pathways of disease

USDA Food Patterns

Choose a variety of foods from the protein foods group, which includes seafood, lean meat and poultry, eggs, beans and peas, soy products, and unsalted nuts and seeds. Increase the amount and variety of seafood consumed by choosing seafood in place of some meat and poultry. Replace protein foods that are higher in solid fats with choices that are lower in solid fats and kcalories.

protein energy malnutrition

Condition that develops when the diet delivers too little protein, too little energy,or both. <--- insufficient food intake

Weight loss and protein

Diets that provide adequate protein (at least 65 to 70 grams a day), moderate fat, and sufficient energy from carbohydrates can better support weight loss and good health. Including protein at each meal may help with weight loss by providing satiety.18 Selecting too many protein-rich foods may crowd out fruits, vegetables, and whole grains, making the diet inadequate in other nutrients.

More about high quality proteins

Generally, foods derived from animals (meat, seafood, poultry,eggs, and milk and milk products) provide high-quality proteins, although gelatin is an exception. Gelatin lacks tryptophan and cannot support growth and health as a diet's sole protein. soy- high quality protein

Kwashiorkor - too little protein

Older infants and young children, 18 months to 2 years of age • Inadequate protein intake, infections • Rapid onset • Some muscle wasting, some fat retention • Growth is 60-80% weight-for-age • Edema and fatty liver • Apathy, misery, irritability and sadness • Loss of appetite • Skin problems

potential risk associated with AA intake 215

Protein deficiency impairs the body's ability to grow and function optimally. Excesses of protein offer no advantage; in fact, overconsumption of protein-rich foods may incur health problems as well. The optimal diet is adequate in energy from carbohydrate and fat and delivers 0.8 grams of protein per kilogram of healthy body weight each day. US and Canadian diets are typically more than adequate in this respect. Normal, healthy people do not need protein or amino acid supplements.

Cancer Protein

Protein does not seem to increase the risk of cancer, but some protein rich foods do. For example, evidence suggests a strong correlation between high intakes of red meat and processed meats are associated with cancer of the colon.1

Protein foods

Protein foods • One ounce equals 7 g of protein 20 percent seafood 70 percent meat poultry egg 10 percent from nuts, seeds, and legumes

Protein deficienc

Protein-energy malnutrition • Medical and nutritional treatment can dramatically reduce mortality rate • Step 1 - Address life-threatening factors • Severe dehydration • Fluid and nutrient imbalances • Step 2 - Restore depleted tissue • Gradually provide nutritionally dense kilocalories and high-quality protein • Step 3 - Transition to foods and introduce physical activity

Kwashiorkor

Severe protein deficiency • Generally result of a diet high in grains and deficient in protein Symptoms range from • Edema in legs, feet, and stomach • Muscle tone and strength diminish • Hair is brittle and easy to pull out • Appear pale, sad, and apathetic • Prone to infection, rapid heart rate, excess fluid in lungs, pneumonia, septicemia, water and electrolyte imbalances

protein RDA 212

The RDA covers the needs for replacing worn-out tissue, so it increases forlarger people; it also covers the needs for building new tissue during growth,so it increases for infants, children, adolescents, and pregnant and lactating women.he protein RDA ♦ for adults is 0.8 grams per kilogram of healthy body weight per day. For infants and children, the RDA is slightly higher.

Recommended intake of proteins

To replace protein, the body needs dietary protein for two reasons. First, dietary protein is the only source of the essential amino acids, and second, it is the only practical source of nitrogen with which to build the nonessential amino acids and other nitrogen-containing compounds the body needs. In a 2000-kcalorie diet, that represents 200 to 700 kcalories from protein, or 50 to 175 grams. Average intakes in the United States and Canada fall within this range.

whey protein:

a by-product of cheese production; falsely promoted as increasing muscle mass. Whey is the watery part of milk that separates from the curds.

Reference protein reference protein:

a standard against which to measure the quality of other proteins.

nutrient and phytochemicals can interact directly with genetic signals that turn on or off, thus

activating and silencing gene expression or indirectly by the way of substances generated by during metabolism

Osteoporosis

adequate protein does not harm bones and may even improve bone mineral density, whereas inadequate intakes of protein may compromise bone health. Osteoorosis is particularly common in elderly women and in adolescentswith anorexia nervosa—groups who typically receive less protein than they need.

proteosome:

all proteins in a cell. The study of all proteins produced by a species is called proteomics. RNA (ribonucleic acid): a compound similar to DNA, but RNA is a single strand with a ribose sugar instead of a deoxyribose sugar and uracil instead of thymine as one of its bases

phenylketonuria (FEN-il-KEY-toe- NEW-ree-ah) or PKU:

an inherited disorder characterized by failure to metabolize the amino acid phenylalanine to tyrosine.

Explain the differences between high-quality and low-quality proteins, including notable food sources of each.

diet that supplies all of the essential amino acids in adequate amounts ensures protein synthesis. The best guarantee of amino acid adequacy is to eat foods containing high-quality proteins or mixtures of foods containing complementary proteins that can each supply the amino acids missing in the other. In addition to its amino acid content, the quality of protein is measured by its digestibility and its ability to support growth. Such measures are of great importance in dealing with malnutrition worldwide, but in countries where protein deficiency is not common, the protein quality of individual foods deserves little emphasis.

To turn on genes-

enzymes attach protein near the beginning of a gene

How environmental factors influence gene expression without changing the DNA

epigenetics

HIgh quality proteins

high-quality proteins: dietary proteins containing all the essential amino acids in relatively the same amounts that human beings require. They may also contain nonessential amino acids.

Activating or silencing a gene leads to an

increase or decrease in synthesis of specific proteins - these processes ultimately affect a persons health.

• Recommended sources • Milk and milk products • Fruits, vegetables, and grains

milk and portein- 1 cup of pimp or yogurt is about 8 gram of protien fruits and vegetables- fruits donot contain protein A serving of vegetable or grain provide 2-3 of protein

nutritional genomics

new field that examines how nutrients influence gene activity and how genes influence the activities of nutrient

How to calculate recommended protein intake

page 213

mutations:

permanent changes in the DNA that can be inherited. nucleotide bases: the nitrogen containing building blocks of DNA and RNA—cytosine (C), thymine (T), uracil (U), guanine (G), and adenine (A). In DNA, the base pairs are A-T and C-G and in RNA, the base pairs are A-U and C-G.

Example of a single gene disorder -- PKU

pheynlketo-uria

genetic expression-

process by which cells convert the genetic code into RNA and protein

Protein and amino acid supplement

protein powder - donot increase the muscle growth, muscle work build muscle supplement Whey protein - by product of cheese production, falsely promote increasing muscle mass

How does digestibility

proteins must be digested before they can provide amino acids. Protein digestibility depends on such factors as the protein's source and the other foods eaten with it. Animal proteins are 90-99% absorbed • Plant proteins are 70-90% absorbed • Soy and legumes are 90% absorbed

microarray technology:

research tools that analyze the expression of thousands of genes simultaneously and search for particular gene changes associated with

genes:

sections of chromosomes that contain the instructions needed to makeone or more proteins. genetics: the study of genes andi nheritance.

others such as phytochemicals activate gene and protect against

some cancer growth

chromosomes:

structures within thenucleus of a cell made of DNA and associated proteins. Human beings have 46 chromosomes in 23 pairs. Each chromosome has many genes.

Arginine

the amino acid arginine may help protect against heart disease by lowering blood pressure and homocysteine levels.13 Additional research is needed to confirm the benefits of arginine. In the meantime, it is unwise for consumers to use supplements of arginine, or any other amino acid for -- lowering BP and homocystiene level

branched-chain amino acids:

the essential amino acids leucine, isoleucine, and valine, which are present in large amounts in skeletal muscle tissue; falsely promoted as fuel for exercising muscles.

The two types of protein

the high quality : animal proteins and plant proteins Complementary proteins : Low-quality proteins combined to provide adequate levels of essential amino acids.

gene expression:

the process by which a cell converts the genetic code into RNA and protein

nutritional genomics:

the science of how nutrients affect the activities of genes (nutrigenomics) and how genes affect the activities of nutrients (nutrigenetics).

genomics:

the study of all the genes in an organism and their interactions with environmental factors.

.epigenetics:

the study of heritable changes in gene function that occur without a change in the DNA sequence.

Recommended Intakes

• Need for dietary protein • Source of essential amino acids • Practical source of nitrogen: needed to build nonessential AA and other nitrogen containing compounds the body need. • 10 to 35 % of daily energy intake • RDA • Adults = 0.8 g / kg of body weight / day • Groups with higher recommended intakes-- For infants and children RDA higher, Same for Athletes as others • Adequate energ