Topics 4/5 Flashcards
Structural protein functionn and groups
provide structural support and enable movement; found in bone teeth, skin, muscles, blood vessels, and hair
contractile proteins- regulate contraction myosin and actin muscle cells
Fibrous proteins- protective and structural, found in connective rtisse, tendons, bone teeth, skin, keratin, fibrin
blood and tissues must maintain pH of 7.35-7.45
What is necessary for synthesis of heat shock proteins
glutamine importance in stress response mechanisms
most abundant aa in body skeletal muscle
non-essential aa
removes excess amonia
building block for making proteins
increases in hypercatabolic conditions
added to TPN solution or enteral feeding
Glutamine synthesis
Glutamine is a non-essential amino acid produced
in the body by glutamine synthesis.
* Produced mainly in muscles, lungs, and liver
* Enzyme: Glutamine synthetase
* Converts glutamate + ammonia into glutamine
* ATP provides energy for the reaction
Roles of proteins
structural, enzymes and hormones, fluid balance, acid-base balance, transport, antibodies and immune response, energy, and satiety
essential vs. non-essential aa
essential aa cannot be synthesized by body and are obtained through diet
My tall handsome vegan friend is watering kale leaves
Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan, Valine
Found in protein rich foods
Non-essential aa can be synthesized and produced through metabolic processes using other compounds
both are necessary for protein synthesis, growth and repair
What are the bcaas
essential aa leucine valine and isoleucine
liver lacks enzymes to breakdown BCAA
BCAA go directly to skeletal muscles to be oxidized (especially during exercise) instead of being processed by liver
muscles use for energy
Functions of the 9 essential aa
Histidine: involved in the production of histamine - immune function, digestion, sleep and sexual function.
* Isoleucine: involved with muscle metabolism and immune function,
hemoglobin production, and energy regulation.
* Leucine: growth hormone production, grow and repair muscle tissue, heal
wounds and regulate blood sugar levels.
* Lysine: hormone and energy
production, important for calcium and
immune function.
* Methionine: tissue growth,
metabolism, detoxification, absorption of essential minerals.
* Phenylalanine: involved in the production of neurotransmitters:
dopamine, epinephrine and
norepinephrine.
* Threonine: important role in collagen and elastin. These proteins provide
structure to your skin and connective tissue, forming blood clots, fat
metabolism and immune function.
* Tryptophan: helps maintain nitrogen balance, helps make neurotransmitter: serotonin - regulates your mood,
appetite and sleep.
* Valine: involved in muscle growth, tissue regeneration and energy production.
slow vs fast proteins
fast proteins: whey, amino acid mixtures, protein hydrolysates, soy protein
BCAAs
Ads are absorbed quickly and aid in muscle protein synthesis
fast proteins recommended after workout
Slow Proteins- take closer to 4 hours to digest
casein, egg proteins( all 9 essential aa+ non essential aa)
they provide body with slower and more sustained release of amino acids, such as muscle regrowth overnight
Casein vs whey protein
they are both complete proteins
whey has more leucine
casein has more glutamine
Exogenous sources vs endogenous sources
exogenous(dietary proteins)- animal products- meat, fish, poultry, eggs, dairy
plant products- grains/grain products, legumes, nuts, seeds, vegetables
endogenous (body proteins)- certain amount of protein is always lost during digestion process
intestinal mucosal cells
digestive enzymes and glycoproteins
Plant vs animal protein
- Typically limiting in one or more essential amino
acid - Lower digestibility than animal sources
- Higher consumption of animal-based protein foods:
- Associated with greater gains in lean body mass
in individuals participating in resistance/strength
training exercises
Estimated Average Requirement for adults is ______
* Recommended Dietary Allowance (RDA) for adults =
0.66 g/Kg
0.8g/kg
Evaluation of protein status (body) & quality (food)
*Nitrogen balance/nitrogen status
*Chemical or Amino acid score measures protein quality based on
essential amino acid composition.
*Protein Digestibility Corrected Amino Acid
Score (PDCAAS) measures protein quality based on essential amino acid content and digestibility.
*Protein Efficiency Ratio (PER)
2009 Cengage-Wadsworth involves a comparison of the aa composition of test
protein with an aa reference pattern
PER in baby food
PER measures how well a protein helps with growth.
* Used to assess the protein quality of infant formulas and baby foods
Limitations of PER
* PER does not distinguish between fat mass and muscle mass.
* Measures total weight gain, regardless of body composition
Essential fatty acids
linoleic acid (omega 6)
alpha-linolenic acid (omega 3)
US diet ratio 20:1 / optimal ratio 4:1
Omega-6 (Linoleic Acid): Primarily from vegetable oils, nuts, and seeds.
Omega-3 (Alpha-Linolenic Acid, ALA): Found in flaxseeds, chia seeds, walnuts, and certain oils.
Omega-3 (EPA and DHA): Sourced from fatty fish and fish oils.
