NUTRITION AND COMPLEX MOLECULES Flashcards
The oligosaccharides are usually attached to amino acids ____ (O-linked, synthesized in gOlgi bodies), or _______ (N-linked, synthesized in eNdoplasmic reticulum)
serine
asparagine
promotes thrombosis (platelet adhesion and aggregation) and vasoconstriction; produced by platelets
Thromboxane
VITAMIN B6: PYRIDOXINE is a coenzyme for what reactions?
o Transamination of amino acids
o Decarboxylation of glutamate and histidine
o ALA synthase
o Cystathionine synthase
o Synthesis of niacin from tryptophan
o Glycogen phosphorylase
active form of Vit D3
calcitriol (1,25-dihydroxyvitamin D)
o Thermic Effect of Food
o Increase in metabolic rate after a meal
10%: Diet-Induced Thermogenesis
Erythrocyte transaminase assay is a test for what?
Vitamin B6
Demineralized bones in adults
Osteomalacia
Major source of enerygy during a 100-meter sprint
creatine phosphate (first 4–5 sec) and then anaerobic glycolysis, using muscle glycogen as the source of glucose
Type II (glycolytic) fibers are used predominantly
ACTIVE FORM OF VITAMIN B5: PANTOTHENIC ACID
Coenzyme A
Beriberi
VITAMIN B1: THIAMINE DEFICIENCY
o Partially denatured derivative of ferritin
o Predominates when tissue stores are high
Hemosiderin
MUCOPOLYSACCHARIDOSES
o Hunter syndrome
o Hurler syndrome
o Morquio syndrome
Leukotrienes are products of the enzyme _____
lipoxygenase
principal components of cartilage, found in sites of calcification, most abundant GAG
Chondroitin sulfate
Slow-reacting substances of anaphylaxis, potent constrictors of bronchial airway musculature (role in pathology of asthma)
• Leukotrienes C 4 , D 4 , and E 4
keeps ductus arteriosus open, used for erectile dysfunction
Prostaglandin E 1 (PGE 1 , alprostadil)
inhibits thrombosis, stimulates vasodilation; produces by endothelia cells
Prostacyclin
Unbranched polysaccharides consisting of repeating disaccharide units, alternating acidic sugar-amino sugar.
GLYCOSAMINOGLYCANS (GAGs)
MUCOPOLYSACCHARIDES
energy content of Carbohydrates, proteins, ketones
4 kcal/gram
What increases in alcohol metabolism?
NADH
Majority of energy is used for?
Resting (Basal) Metabolic Rate
first sign of vitamin A deficiency
loss of sensitivity to green light
Microsomal ethanol oxidation system requirement for Alternate pathway for ethanol metabolism
CYP2E1
Examples of GLYCEROPHOSPHOLIPIDS / PHOSPHOGLYCERIDES
- Phosphatidylcholine
- Phosphatidylethanolamine
- Phosphatidylserine
- Phosphatidylinositol
- Dipalmitoylphosphatidylcholine
- Cardiolipin
results in vasoconstriction and contraction of smooth muscle, stimulates uterine contractions
Prostaglandin F 2α (PGF 2α ) - dinoprost, carboprost
o Energy expenditure at rest but not asleep
o Measured at 12 hours after the last meal
o Depends on weight, age and gender
60%: Resting (Basal) Metabolic Rate
Iron transport protein in plasma
Transferrin
o Alternate pathway for ethanol metabolism induced in chronic alcoholics
o Has a much higher Km for ethanol, utilized when ethanol concentrations are high
Microsomal ethanol oxidation system
Differentiate Kwashiorkor vs Marasmus
examples of GLYCOPROTEINS
- Mucins
- Transferrin, cerruloplasmin
- HGC, TSH
- Immunoglobulins
Intestinal absorption of copper is intact, but its biliary excretion is blocked
Wilson Disease
- Copper accumulation in liver and brain, with resulting liver damage, neurological deterioration, or both
- Kayser-Fleisher rings
- Unusually low levels of 3-methylhistidine in urine
o Average daily dietary intake level that is sufficient to meet the requirements of >95% of all individuals in a life stage and gender group
Recommended Daily Allowance (RDA)
- Energy-rich molecules larger than that of the other dietary nutrients
- Fats, carbohydrates and protein
- May include ethanol in some diets
MACRONUTRIENTS
VITAMIN B7/H: BIOTIN is a coenzyme for what enzymes?
o Pyruvate carboxylase
o Acetyl CoA carboxylase
o Propionyl CoA carboxylase
• Possible Etiologies:
o Corn-based diet
o Hartnup disease
o Carcinoid syndrome
o Isoniazid use
VIT B3 DEFICIENCY
* In Hartnup disease, the body is unable to absorb tryptophan. In carcinoid syndrome, majority of the body’s tryptophan is converted to serotonin, leaving very little for niacin synthesis.
o Storage form of iron in liver, spleen, bone marrow, intestinal mucosa, pancreas, myocardium, and other tissues o More abundant storage form when the tissue stores are low
Ferritin
Least toxic of the fat-soluble vitamins
Vit E
Prostaglandins and thromboxanes are products of the enzyme ______
cyclooxygenase (COX-1, COX-2)
leading cause of preventable blindness worldwide
Vitamin A deficiency
• Seborrheic dermatitis
• Cheilosis
• Angular stomatitis
• Desquamation and inflammation of the tongue
VITAMIN B2: RIBOFLAVIN DEFICIENCY
only significant sphingophospholipid in humans, constituent of myelin sheath, which insulates the axons of nerve fibers and increase nerve conduction
Sphingomyelin
Microsomal ethanol oxidation system occurs where?
smooth endoplasmic reticulum
Keshan Disease is associated with
SELENIUM deficiency
*low selenium content causing cardiomyopathy, endemic in parts of China
Give the enzyme.
Acetaldehyde → Acetate
Aldehyde dehydrogenase
Inhibitor: Disulfiram
Occurs in a few oxidase enzymes, including xanthine oxidase
MOLYBDNENUM
associated with Peripheral nerve damage (Nutritional melalgia or “burning foot syndrome”)
VITAMIN B5: PANTOTHENIC ACID DEFICIENCY
Most common micronutrient deficiency worldwide
Iron Deficiency Anemia
results in vasodilation and relaxation of smooth muscle, used to induce labor
Prostaglandin E 2 (PGE 2 ) - DInoprostone
Average dietary energy intake predicted to maintain an energy balance in a healthy adult of a defined age, gender, and height, whose weight and level of physical activity are consistent with good health
ESTIMATED ENERGY REQUIREMENT (EER)
- Depends on level of activity
- Sedentary 30 kcal/kg/day
- Moderately active 35 kcal/kg/day - commonly used
- Very active 40 kcal/kg/day
Most abundant trace mineral in the body after iron, with total body stores of about 1.5 to 2.5 g
ZINC
Examples of GLYCOSAMINOGLYCANS (GAGs) / MUCOPOLYSACCHARIDES
- Hyaluronic acid
- Chondroitin sulfate
- Keratan sulfate
- Heparin
- Heparan sulfate
- Dermatan sulfate
Erythrocyte transketolase activity assay is a test for what vitamin?
Vitamin B1
SPHINGOLIPIDOSES
* Glycolipids are members of the class of sphingo- lipids
o Tay-Sachs disease
o Niemann-Pick disease
o Gaucher disease
Acrodermatitis enteropathica is associated with
ZINC deficiency
o Rare recessively inherited disease with dermatitis, diarrhea, and alopecia due to impaired intestinal zinc absorption
o Treated with high doses of oral zinc
Give the enzyme.
Ethanol → Acetaldehyde
Alcohol Dehydrogenase
Vit D. deficiency in Children
Rickets
Derived from 20-carbon fatty acid, arachidonic acid which is cleaved from cell membrane phospholipids by the enzyme phospholipase A2
EICOSANOIDS
PROSTAGLANDINS
THROMBOXANES
EUKOTRIENES
(lecithin) most abundant glycerophospholipid, cell membraine outer leaflet, storage of choline component of acetylcholine
Phosphatidylcholine
To lose 1 pound/week, you need to burn and/or reduce caloric intake by about _____
500 kcal/day
Thiamine is a Coenzyme for what enzymes?
o Pyruvate dehydrogenase
o α-ketoglutarate dehydrogenase
o Branched-chain amino acid dehydrogenase
o Transketolases
What does Microsomal ethanol oxidation system consume to form acetaldehyde?
NADPH
(also requires CYP2E1)
BMI classification
Phospholipid with sphingosine backbone
SPHINGOPHOSPHOLIPIDS
- Nutrients needed in lesser amounts
- Vitamins and minerals
MICRONUTRIENTS
Phospholipid in which an alcohol (“X”) is attached by a phosphodiester bridge to diacylglycerol.
GLYCEROPHOSPHOLIPIDS
PHOSPHOGLYCERIDES
energy contant of alcohol
7 kcal/gram
Formiminoglutamic acid (FIGlu) excretion test is for what vitamin?
Folate
Proteins to which oligosaccharides (short chains of carbohydrates) are attached.
GLYCOPROTEINS
MUCOPROTEINS
Derivatives of ceramide in which a long-chain fatty acid is attached to a sphingosine backbone.
GLYCOLIPIDS
GLYCOSPHINGOLIPIDS
Pellagra
VITAMIN B3: NIACIN DEFICIENCY
Diarrhea, dermatitis, dementia
VITAMIN B12: COBALAMIN is a coenzyme for what enzymes?
o Methionine synthase
o Methylmalonyl CoA mutase
Pseudotumor cerebri is associated with?
Vitamin A Toxicity
* patients present with symptoms of increased intracranial pressure.
discuss the metabolism of ALCOHOL
energy contetnt of FATS
9 kcal/gram
Iron overload syndrome with progressive hemosiderosis and resulting organ damage
Hemochromatosis
* ↑ Total plasma iron, ↑ Transferrin saturation, ↑ Serum ferritin, ↓Total iron binding capacity
excess can cause psychosis & parkinsonism
Manganese Madness
Only water-soluble vitamin with significant toxicity
Vit B6 Toxicity
major source of energy in marathon
aerobic metabolism, using blood glucose and free fatty acids, derived from breakdown of triacylglycerol from adipose tissue
Type I (oxidative) fibers are used predominantly
o Average daily nutrient intake level estimated to meet the requirement of 50% of healthy individuals in a particular life stage and gender group
Estimated Average Requirement (EAR)
Schilling test and Methylmalonic acid test are tests for what vitamin?
Vitamin B12
Highest average nutrient intake level that is likely to pose no risk of adverse health effects to almost all individuals in the general population
Tolerable Upper Intake Level
o X-linked recessive disorder caused by the deficiency of an ATP dependent membrane transporter for copper
o Impaired transfer of copper from intestinal mucosal cells to the blood, and intracellular transport is abnormal as well
Menkes disease
*Growth retardation, mental deficiency, seizures, aneurysms, bone demineralization, brittle hair
VItamin D and Vitamin B3 requires what other vitamin?
vitamin B6
