Macronutrients Flashcards
(230 cards)
1
Q
What are the 3 major macros?
A
- Carbs
- Lipids
- Proteins
2
Q
How do we measure macros?
A
Gram quantities
3
Q
What is the purpose of macros?
A
Provide us with energy (calories)
4
Q
What does the AMDR tell us?
A
Acceptable Macronutrient Distribution Range
Percentage of energy intake that should come from each macro for optimal body fxn
5
Q
What are the AMDRS for carbs, lipids, and proteins?
A
Carbs - 45-65% cal
Lipids - 20-35% cal
Proteins - 10-35% cal
6
Q
How do we derive our protein RDA?
A
0.8 g/kg body weight
7
Q
T/F: Men require more fiber than women.
A
True - men need 38g, women need 25g
8
Q
What manufactures carbohydrates?
A
Plants
9
Q
What are the 2 major categories of carbs/what are contained in each category?
A
Simple:
- Monosaccharides
- Disaccharides/Oligosaccharides
Complex:
3. Polysaccharides
10
Q
What is C1(H2O)1?
A
Hydrated carbon aka 1 carbohydrate
11
Q
How many Cal/g do we get per carbohydrate?
A
4 Cal/g
12
Q
What are the 3 monosaccharides?
A
Glucose
Fructose
Galactose
13
Q
What are the 3 disaccharides?
A
Sucrose
Lactose
Maltose
14
Q
What are the 3 polysaccharides?
A
Starch
Glycogen
Fiber
15
Q
How many carbons are in a monosaccharide?
A
3-7
MC are 6C = hexose
16
Q
What is the sweetest of all monosaccharides?
A
Fructose
17
Q
What is the epimer/isomer of glucose?
A
Galactose
18
Q
What is galactosemia?
A
Inability to metabolize galactose
19
Q
Which of the 3 monosaccharides is required by the brain?
A
Glucose
20
Q
Which carbohydrates are digested by brushborder enzymes?
A
Disaccharides (bound by glycosidic bonds)
21
Q
Which disaccharide is Glucose (alpha1-beta2) fructose?
A
Sucrose
22
Q
In older men and women, does our fiber RDA increase or decrease?
A
Decrease
men - 30g
women - 21g
23
Q
What is the difference in taste between simple and complex carbohydrates?
A
Simple = sweet Complex = not sweet
24
Q
Which carbohydrate is a ‘non-reducing’ sugar?
A
Sucrose (derived from glucose + fructose)
25
What is an invert sugar?
Free glucose and fructose in a 1:1 ratio
Honey is a natural example
26
What is the most common form of carbohydrate malabsorption?
Lack of lactase (25% of adults world wide)
Galactose beta(1-4)
**Beta means indigestible/hard to break, alpha means digestible
27
What is the product of starch degradation?
Maltose (derived from glucose + glucose)
Glucose alpha(1-4)
28
What is the current recommendation for added sugars in food?
<10% of total energy consumed
29
How long are oligosaccharides?
3-10 sugars
30
How can we describe oligosaccharides?
Difficult to digest - act as fibers
Water soluble
Often sweet
31
How many sugars comprise polysaccharides?
10 or more
32
Which polysaccharide comes from plants? Which comes from animals? Which comes from plants but is indigestible?
Plants - Starch
Animals - Glycogen
Indigestible - Fiber
33
What is a branched starch? Linear starch?
Branched - amylopectin
| Linear - amylose
34
Which type of starch is corn and rice based and contains a high percentage of amylopectin?
Waxy starch - seen in frozen foods
35
What is a resistant starch?
Recrystallizes after cooking to resist digestion (usually fermented)
36
Which polysaccharide is 100% glucose?
Starch
37
Which starch is most resistant?
RS3 - retrograded from cooling gelatinized starch
38
What is the difference in appearance between amylose, amylopectin and glycogen?
Amylose is linear (plant starch)
Amylopectin has long, infrequent branches (plant starch)
Glycogen is highly branched (remember: glycogen is an animal starch)
Note: Amylopectin and Glycogen have the same bond
alpha(1-4)>alpha(1-6)
39
Where does digestion of starch begin? What enzyme is required?
Begins in the mouth with alpha-amylase (randomly digests alpha(1-4) bonds
40
What is the yield of alpha-amylase
Dextrins (medium length glucose strands from amylose)
Limit Dextrins (medium length containing alpha(1-6) from amylopectin)
41
Which brushborder enzymes are required to digest dextrins/limit dextrins?
Maltase & Isomaltase
42
T/F: Glycogen is found in plants and animals.
False! Animals only!
43
What is the storage form of carbs in plants? In animals?
Plants - starch
| Animals - glycogen
44
What regulates blood glucose?
Liver
100g = 400kcal when full
45
How long can we store glycogen in the liver before it is depleted (fast state)
15 hours
46
How much glycogen is used in the liver after 1 hour of aerobic activity?
50%
47
How much glycogen is released from muscle?
None - once phosphorylated it remains in the muscle
48
How much glycogen is stored in the muscle?
350g = 1400 kcal in sedentary individual
**May double in trained muscle**
49
What is a functional fiber?
Fiber that has been extracted from plants and added to foods/supplements
50
What are the two types of dietary fiber?
Insoluble and soluble
51
What are the two types of soluble fiber?
Viscous fiber (good binder/gel-forming)
Fermentable fiber (metabolized by colonic bacteria)
52
Which fiber swells in water?
Soluble fibers
53
What is an example of a lignin?
Woody stalks of broccoli or asparagus
54
Which types of fiber are both viscous and fermentable?
Pectin
Beta-glucans
**Gums can be both, but guar gum specifically is fermentable only*
55
What fibers are only viscous?
Psyllium
| Konjac Glucomannan
56
What fibers are only fermentable?
Inulin
Wheat Dextrin
Guar Gum
57
What food can contain up to 14g fiber/serving?
Bran cereals
58
What are good sources of fiber?
Beans, Veggies
59
What are okay sources of fiber?
Fruit, Nuts, Seeds, Breads
60
Which type of fiber increases fecal volume and decreases GI holding time?
Insoluble fiber (cellulose, lignin, some pectins)
61
Which fiber can decrease absorption of cholesterol and minerals?
Soluble fiber
62
What are the bi-products of fermentable fiber?
Gas
| Short chain FA (energy)
63
Which two mineral binders are present in fiber rich foods?
Phytate
| Oxalate
64
What can help decrease the risk of type II diabetes?
Increased consumption of soluble fiber (limits glucose absorption)
65
How many grams of fiber intake/day are required to decrease risk of colorectal cancer?
10g of dietary fiber (reduces risk by 9%)
66
What is the adult RDA for carbs?
130g/day
67
T/F: The Average American adult consumes 12-18g of fiber/day, surpassing their AI levels.
While the American average is true, this statement is FALSE because the AI for adults 18-50 is 38 (men) and 25 (women), respectively (levels decrease after 50)
68
What is a normal fasting blood glucose level?
70-99 mg/dL
69
What peptide hormones regulate blood glucose levels?
Insulin & Glucagon
70
What levels of fasting blood sugar are considered pre-diabetic?
100-125 mg/dL
71
How does eating carbs effect blood glucose levels in a healthy patient?
1. Eating carbs raises blood glucose
2. Pancreas releases insulin from beta cells
3. Insulin binds to insulin receptors
4. IRS-1 is recruited to the receptor
5. IRS-1 begins a signal transduction cascade to tell the golgi complex to make GLUT4
6. GLUT4 is translocated from golgi complex to plasma membrane
7. Glucose is able to enter muscle or adipocytes for storage or use
8. Blood glucose decreases to normal
72
How does eating carbs effect blood glucose levels in a insulin-resistant patient?
1. Insulin binds to insulin receptors
2. IRS-1 is recruited to the receptor
3. Excess inflammation (C-reactive protein/CRP) abnormally phosphorylates IRS-1 (on 2 serine residues), causing it to not signal properly
73
How does insulin use glucose in the cell (from low to high levels of glucose)?
ATP
Store glucose to glycogen in muscles & liver
Turn into adipose tissue
74
How does a healthy patient respond to low blood glucose levels?
1. Blood glucose drops between meals
2. Pancreas releases glucagon from Alpha cells
3. Glycogen is broken down into glucose
4. Glucocorticoids inhibit glucose uptake
5. GNG occurs
6. Blood glucose increases to normal levels
75
How does low blood glucose affect adipose?
Fatty acids and Glycerol (Triglycerides) enter the blood stream
76
How does low blood glucose affect muscle?
Lactate (from pyruvate/glycogen) and Alanine (protein) enter the blood stream
77
What are the 2 main mechanisms of making ROS?
Respiratory burst (MC)
ETS
78
What's the cofactor for GPx?
Selenium
79
What's the cofactor for CAT?
Iron
80
What is responsible for turning H2O2 into H2O?
GPx
CAT
81
What is Glutathione (GSH)? Where is it found? Where is it primarily used?
Antioxidant tripeptide synthesized in the liver
Found in plasma and cytoplasm and mitochondria of cells
Primarily used in Liver
82
Where is catalase found?
WBCs and peroxisomes of cell
83
What are examples of fat-soluble H donators?
Coenzyme Q10
Carotenoids (proformed vit A)
vitamin E (found in membranes)
84
What are examples of water-soluble H donators?
Vitamin C
Glutathione
Polyphenols
BHA/BHT
**High concentrations in fruits/veggies/whole grains/legumes**
85
What helps to regenerate vitamin E?
*Vit C
Beta carotene
CoQ10
Glutathione
**Vit E acts as potent anti-oxidant. If you over-supplement with Vit E it can act as a pro-oxidant. We want to get AOX at smaller/natural concentrations
86
What are the benefits of Alpha-Lipoic acid?
Required for ATP synthesis
Aids in nerve regeneration
Anti-inflammatory
Anti-oxidant
**Body produces it; both fat/water soluble**
87
What are the 6 major nutrients of concern in a vegetarian diet?
```
Vit D (non-lacto)
Calcium (non-lacto)
Zinc (non-pesco, non-semi)
B12 (vegan)
Iron (RDA is 1.8 times higher for ALL vegetarians)
Omega-3s (non-pesco, non-semi)
```
88
What is the average caloric requirement for a vegan?
2383 cal (vs 2985 for omnivore)
**vegans require the least amount of calories compared to other vegetarians**
89
Where do we synthesize plasma proteins?
Liver!
90
What is the major glucogenic AA released from muscle?
Alanine
91
What are the causes & symptoms of Hyperglycemia?
Caused by persistently high blood glucose levels
Diabetic levels = >126mg/dL
Symptoms: frequent urination, dehydration, thirst
**Kidney can't reabsorb all the glucose in these patients, therefore it winds up in the urine, pulling lots of water with it
92
Which type of diabetes is a GLUT 4 issue?
Type II
93
What is the difference between type I and type II diabetes?
Type I: insulin dependent, autoimmune, insulin injections
| Type II: insulin independent, poor diet/sedentary lifestyle, lose weight and eat healthy
94
What nutrients have the greatest affect on blood glucose and increase triglycerides?
Sugar & starch
95
T/F: Dietary fiber increases blood glucose levels.
False!
**Subtract any dietary fiber amounts from the total carbs shown on nutrient label for a more accurate representation of carbohydrates**
96
T/F: Low glycemic foods may be beneficial for type II diabetics.
True!
97
What are examples of foods with a low GI?
Low GI = 56 or under
Oatmeal, fruit, non-starchy veggies, legumes, chocolate, sweet potatoes, lentils
98
What foods have a high glycemic index?
High = 70+
Pretzels, cereal, mac & cheese, white rice
99
What is the glycemic load (GL)?
How much fiber is in a product
**Better measure of how a food impacts blood sugar
100
What condition can be the result of high carb intake?
Hypertriglyceridemia
101
At what blood sugar levels does fat begin to burn? At what blood sugar levels does glucose spill into the urine?
Fat burn = <40 mg/dL
Urine = >180 mg/dL
102
What is the pathway for carb/blood lipid interaction?
Carbs stimulate insulin release
Insulin facilitates glucose uptake & lipid synthesis in liver
Triglycerides are packed into VLDL and sent into the blood
103
What are the best nutritional swaps to make to decrease your risk of congestive heart disease?
1. Swap triglycerides for MUFAs and PUFAs
2. Swap saturated fats for PUFAs
3. DO NOT swap UFA for carbs
104
What are the 5 fates of blood glucose?
1. Muscle glycogen
2. Stored as fat
3. Liver glycogen
4. Sent to the kidney for excretion in urine
5. Sent to other tissues for glycolysis
105
What are the 2 major roles of carbs in the body?
1. Fuel activity
| 2. Spare proteins
106
What bond holds AA together?
Peptide bond
107
What denatures proteins?
Heat
| Extreme pH
108
What are the essential AAs?
PVT MT HILL
Phenylalanine
Valine
Tryptophan
Methionine
Threonine
Histidine
Isoleucine
Leucine
Lysine
109
What AAs become essential if their precursor is deficient?
Arginine
Cysteine
Glutamine
Glycine
Proline
Tyrosine
110
Where are the sites of protein digestion? What hormones are involved? How is protein absorbed?
Stomach - denatured by HCL, broken down by Pepsin
SI - pancreatic enzymes digest to AA, di/tripeptides
Absorbed via active transport
111
What are the reference proteins used for PDCAAS (Protein digestibility corrected AA score)?
Eggs & Milk
**Animal protein digestion > Plant protein digestion**
112
What is the only macro with nitrogen?
Protein
113
What is a food that contains all essential AA? Examples in plants/animals?
Complete protein
Plants: ONLY Quinoa, soy, amarinth
Animals: Eggs, meat, human milk, poultry, seafood, dairy - NO GELATIN
114
What is a food that does not contain all essential AAs?
Incomplete proteins
Corn
Wheat
Rice
Legumes
115
Corn is deficient in what AAs?
Lysine
| Tryptophan
116
Wheat is deficient in what AA?
Lysine
117
Rice is deficient in what AA?
Lysine
118
Legumes are deficient in what AA?
Methionine
119
What are complimentary proteins?
Combining two incomplete proteins together to provide all 9 essential AA (red beans & rice)
120
What contributes to a positive nitrogen balance?
Consuming more N than we excrete
Muscle building, periods of growth, healing after illness
Required for somatic (muscle mass) and visceral proteins (organ proteins)
121
What contributes to a negative nitrogen balance?
We excrete more N than we consume
Illness, starvation, CA, AA deficiency, HIV/AIDS, sever burns
122
T/F: Eating veggie protein instead of animal protein decrease risk of heart disease
True
123
T/F: All red meat increases risk of colorectal CA.
False - processed red meat has a higher risk
124
What is the recommended calcium to protein ratio to prevent Osteoporosis?
>20:1
125
What is the term for protein-energy malnutrition? What are the associated symptoms?
Marasmus
```
Skin/bone appearance
Anemia
Weak immune system
Stunted brain development
Depressed metabolism
Fluid/electrolyte imbalance
```
126
What is protein malnutrition? Associated symptoms?
Kwashiorkor
```
Stomach distension
Loss of appetite
Fatty liver
Stunted growth/development
Dry, brittle hair
Skin pigmentation
```
127
What is the protein RDA in sedentary individials ?
0.8 g/kg body weight OR 0.36 g/lb body weight
128
What is the AMDR (acceptable macronutrient distribution range) for protein?
10-35% energy
129
How much energy does the average American get from protein?
15-17%
130
T/f: If a 155lb male has a diet largely consisting of high quality animal protein, he needs less protein than if he were to consume a high plant protein diet.
True - Normally, a 155lb male would require 56g daily
High animal diet = 45 g/d
High plant diet = 65 g/d
131
T/F: A lot of AA oxidation occurs in muscle during resistance training.
False
132
What is the protein RDA for resistance training?
1.5-1.7 g/kg body weight per day
**Best to consume 1-2 hours before exercise and within 2 hours post-exercise
133
What is the protein RDA for active adults?
0.8-1.0 g/kg
134
Which 4 foods have the highest PDCAAS?
Casein (slow digestion, more leucine than soy, best to take before bed)
Whey (fast digestion, more leucine than soy)
Cow's milk
Egg (faster digestion, less leucine than whey, more than soy)
135
What is hydrolysate?
AA & peptide produced by heat and/or acid
Absorbed faster
Increase insulin secretion
Stimulates protein synthesis over intact/whole protein
136
When does protein require a % daily value?
Foods making a label claim for protein
Foods intended for consumption in kids 4 and under
(Takes into account protein quantity/quality)
137
What are the big 8 food allergens (cause 90% food allergies)?
```
Tree Nuts
Peanuts (0.6%)
Shellfish (2.8% adults)
Soy
Fish (0.2% kids, 0.5% adults)
Eggs (1-2% kids)
Milk (1-2% kids)
Wheat (0.8% adults)
```
138
Which food allergies persist into adulthood?
Peanuts
Shellfish
Fish
Tree Nuts
139
Which food allergies are commonly outgrown?
Milk
Eggs
Wheat
Soy
140
What are the proper steps in conducting an elimination diet?
1. Avoid offending foods for 2-4 weeks (symptoms should disappear)
2. A challenge test must be conducted to confirm (symptoms should reappear)
3. Avoid offending foods for 2-4 weeks (symptoms should disappear)
141
What is the oral food challenge (OFC)?
Start with an elimination diet for 2 weeks (up to 6 weeks of other GI issues are present)
Gradually increase suspected foods under adult supervision over hours/days
Be prepared for anaphylaxis!
142
T/F: The presence of IgG in the blood means the body is conducting an allergic response.
False - IgG is elevated in response to desensitization reactions
**Allergen specific IgG has been shown to block IgE allergic responses**
143
What is the gold standard of allergy testing?
The elimination diet
144
What causes Celiac Disease?
IgA reaction to Gliadin
145
Are gluten free diets healthier?
Gluten free diets frequently lack B vitamins and are higher in saturated fat and sodium
146
What are the most widely consumed FA?
18 C
147
What is the composition of a TG?
3 FA attached to one glycerol
148
What is the range of size of FA?
4-24 carbons long, most evenly numbered
149
What is the difference between hydrogens in a saturated vs unsaturated fat?
Saturated = carries maximum number of hydrogen
Unsaturated = FA that lacks hydrogen atoms (contains at least 1 double bond)
150
How many double bonds are present in SFA/MUFA/PUFA?
SFA = fats = no double bonds
MUFA = oils = 1 double bond
PUFA = oils= more than 1 double bond
151
How long are short chain fatty acids? Examples?
4-6 C long
Butyric acid
152
How long are medium chain fatty acids? Examples?
8-12 C long
Lauric acid
153
How long are long chain fatty acids? Examples?
14-24 C long
Palmitic acid, Essential fatty acids
154
How are short & medium chain FA transported in the blood vs mitochondria?
Blood: FFA bound to albumin
Mit: Does not require L-carnitine
155
How are long chain FA transported in the blood vs mitochondria?
Blood: As triglycerides in chylomicrons, VLDL, HDL, LDL
Mit: Requires L-carnitine
156
What are the 4 saturated FA? (number/name)
12: 0 - Lauric acid - coconut oil
14: 0 - Myristic acid - coconut/palm oil
16: 0 - Palmitic acid - palm oil/cocoa butter
18: 0 - Stearic acid - cocoa butter/animal fats
157
What produces synthetic trans fats?
Partial hydrogenation
* *Increases the risk of HD the most out of any lipid
* *Causes the most negative impact on blood lipids
158
Where can we find trans fats naturally?
In dairy products as conjugated linoleic acids
159
What are the 6 unsaturated FA? (number/name)
| Which are omega 3/omega 6?
18: 1 - Oleic acid
18: 2- Linoleic acid (omega-6)
18: 3 - alpha-linoleic acid (omega-3)
20: 4 - ARA (omega-6)
20: 5 - EPA (omega-3)
22: 6 - DHA (omega-3)
160
In a phospholipid, where is the SFA, UFA, and polar head group located?
SFA = sn-1
UFA = sn-2
Polar head group = sn-3
161
What is the most predominant phospholipid in the body?
Lecithin
**Comprised of Palmitic acid (sn-1) Oleic acid (sn-2), and Choline (sn-3)
162
What are the major functions of phospholipids?
Emulsifier to mix fats with water in salad dressing, candy bars, etc
Cell membrane bilayer
Aid in transport of fat-soluble compounds
Naturally found in all foods, esp. liver, eggs, peanuts, soybeans, wheat germ
163
T/F: Plant sterols inhibit cholesterol absorption
True
164
What are the 4 major roles of sterols?
Vitamin D
Bile Acid
Steroid hormones
Cell membranes
165
What is the major benefit of hydrogenating?
Increases shelf life
166
What are synthetic lipids?
Medium chain triglycerides
**by-product of margarine production, used in patients with fat malabsorption
EG CAPRENIN (5 kcal/g) OR OLESTRA (0 kcal/g)
167
How are lipids digested?
Mouth - lingual lipase
Stomach - gastric lipase & peristalsis
SI - Pancreatic lipase & bile
168
How are lipids absorbed?
1. Micelles are absorbed via passive diffusion
| 2. TG, phospholipids, and cholesterol esters are reformed in the smooth ER
169
What are lipoproteins? Describe their structure.
Lipid transport molecules
Exterior = phospholipid (water-soluble)
Lipid Core = TG, cholesterol, fat-soluble vitamins
Apoproteins = protein portion (enzymes, receptor ligands)
170
How are fat-soluble vitamins and dietary fat transported?
Chylomicrons
**Travel through lymphatic system to thoracic duct, transported to adipocytes
171
What activates lipoprotein lipase? What is its fxn?
Apoprotein on chylomicrons & VLDL (apoC-2)
**Breaks down TG to glycerol & FA
172
What happens to the TG-depleted chylomicrons?
Returns to the liver (where it is recycled) after 14 hours of circulation
173
Where does the liver get lipids (4)?
1. Chylomicron remnants
2. Circulating fatty acids
3. Uptake of other lipoproteins (HDL, LDL)
4. Endogenous lipid synthesis in the liver
174
Once the liver has lipids, what happens?
Packaged into VLDL (more cholesterol than chylomicrons, activates lipoprotein lipase)
TG-depleted VLDL becomes cholesterol rich LDL
175
How does free cholesterol regulate cellular cholesterol concentrations?
Decreases LDL receptor synthesis
Promotes cholesterol storage as cholesterol ester
Inhibits HMG CoA reductase
176
What is the function of HDL?
Picks up free cholesterol from cells and brings it back to liver
COPPER DEPENDENT enzyme required = LCAT (lecithin:cholesterol acyltransferase)
Anti-inflammatory
177
Which lipoproteins contain mostly TG?
Chylomicrons (made in SI) & VLDL (made in liver)
178
Which lipoprotein contains mostly cholesterol?
LDL
179
Which lipoprotein contains mostly protein?
HDL (made in SI/Liver)
180
Which apoprotein found on HDL inhibits LCAT?
ApoA-II
181
Which apoprotein found on HDL and chylomicrons activates LCAT?
ApoA-IV
182
Which apoprotein induces lipoprotein lipase?
ApoC-II
183
Which apoprotein inhibits lipoprotein lipase?
ApoC-III
184
Which apoprotein found on HDL activates the LCAT enzyme to pick up free cholesterol?
ApoA-I
185
T/F: Triglycerides provide energy to the cell during high-intensity, short duration exercise.
False - low-intensity, long duration exercise
**Also during sleep
186
How is a TG broken down into glycerol and 3 FFA?
TG ---> DG via adipose triglyceride lipase
DG --->MG via Hormone sensitive lipase
MG ---> glycerol/3 FFA via RATE LIMITING Monoglyceride lipase
187
Which pathway requires glycerol to make glucose?
GNG
188
What happens to the 3 FFA during rest vs exercise?
Rest: 70% are reesterified into TG
Exercise: 25% are reesterified into TG
189
What is the function of the IMTG pool?
Represents about 1% of whole body lipid stores
Could provide up to 25% of energy during moderate-intensity exercise
2-3 times more in type 1 fiber vs type 2
190
How does the IMTG pool break down fats in active individuals?
1. Adipose triglyceride lipase (ATGL) is activated via phosphorylation of Ser406 by PKA (protein kinase A) and AMP kinase
2. Hormone sensitive lipase is activated via phosphorylation of 5 serines by PKA & ERK, but INHIBITED by AMPK
191
How does the IMTG pool break down fats in sedentary individuals?
The pool in sedentary people is made up of TG, DG, and ceramide
ATGL is upregulated in obese men
HSL is downregulated in obese men
DG activates PKC and induces serine phosphorylation of IRS-1 leading to INSULIN RESISTANCE
192
What are the symptoms associated with Omega-3 deficiency?
PN and decreased visual acuity
**V Rare**
193
What are the symptoms associated with Omega-6 deficiency?
Scaly skin & extreme thirst due to breakdown of epidermal barrier for water loss
Poor wound healing
Impaired reproduction
Now you dead, good job
194
In the COX/LOX pathway, what is associated with ARA (n-6)?
COX - 2 series PG/TX (inflammation/clotting)
| LOX - 4 series LT (inflammation)
195
In the COX/LOX pathway, what is associated with EPA (n-3)?
COX - 3 series PG/TX (little to no effect)
| LOX - 5 series LT (little to no effect)
196
What fatty acids increase LDL?
Lauric acid, Myristic acid, Palmitic acid, Trans fat
197
What FA has no effect on LDL?
Stearic acid
198
What FA decrease LDL?
MUFA
| PUFA
199
What is the AMDR for lipids?
20-35% (shoot for 30%)
200
What are the three major reactive species categories?
ROS radicals - superoxide & hydroxyl
ROS nonradicals - Singlet O2 & Hydrogen peroxide
RNS Radical - Nitric Oxide
201
How is Superoxide produced?
Respiratory burst of WBCs
During normal metabolism in ETC
During detox by CP450 enzymes
**Not able to diffuse through lipid bilayer; stuck in cells
202
How is hydrogen peroxide produced?
Respiratory burst of WBCs from O2
Hypoxia
**Able to diffuse through lipid bilayer
203
What is the Fenton reaction (aka Haber Weiss rxn)?
In the presence of free iron, copper, cobalt, or chromium, a hydroxyl radical can form
**Hydroxyl radicals can also be formed by superoxide & hydrogen peroxide reaction
204
Why are hydroxyl radicals so bad?
They are the most potent & aggressive of all radicals b/c they can attack ANY compound in the body, including DNA!
Increase risk of HD, CA, dementia, etc
**Have short half life
205
What are the 3 enzymatic AOX?
SOD
GPx
CAT
206
What are the 3 nonenzymatic AOX?
H donors
Metal binders
Oxygen scavengers
207
Where is SOD1 found/what are its cofactors?
Inner mitochondria
Zinc & Copper
208
Where is SOD2 found/what are its cofactors?
Mitochondrial matrix
Manganese
209
Where is SOD3 found/what are its cofactors?
Cytosol
Zinc & Copper
210
Where is GPx synthesized?
Liver
211
Where is Glutathione Peroxidase found? Cofactor?
Plasma, cytoplasm, and cell mitochondria
Requires selenium
212
Where is Catalase found? Cofactor?
WBCs and peroxisomes of cell
Requires Iron
213
What are the 4 metal chelators? What are they binding?
Binding Cu, Co, Fe
Oxalate (legumes)
Phytate (whole grains)
Tannins (tea, coffee, red wine)
EDTA (synthetic)
214
What vitamin is an oxygen scavenger?
Vitamin C
215
How are carbs metabolized in the liver in an absorptive state?
Liver picks up 60% of all glucose, which is phosphorylated into glucokinase
Increased glycolysis & glycogen synthesis (due to insulin)
Decreased GNG
216
How are lipids metabolized in the liver in an absorptive state?
Increased FA synthesis due to availability of substrates affected by insulin)
Increased TG available from chylomicrons
TG are packed into VLDL, lipoprotein lipase activated, TG-depleted VLDL becomes LDL
217
How does LDL get into the cell?
apoB-100 binds to LDL receptor
lysosome digests LDL into AA, phospholipids, cholesterol, & FA
218
How is protein metabolized in the liver in an absorptive state?
AA degradation (except BCAA) - more AA available than liver can handle
Slight increase in protein synthesis to replace what was lost during fasted state
219
How are carbs metabolized in adipose tissue in an absorptive state?
Insulin stimulates GLUT4 for glucose transport
Increased glycolysis to make glycerol for TG backbone
Glucose metabolized by hexose monophosphate (resulting in NADPH for TG synthesis)
220
How are lipids metabolized in adipose tissue in an absorptive state?
Low de novo synthesis
FA in adipocytes come from chylomicrons & VLDL
FA stored as TG (insulin)
Hormone sensitive lipase is inactivated, preventing TG degradation (insulin)
221
How are carbs/lipids/proteins metabolized in skeletal muscle in an absorptive state?
Carbs: Increased GLUT4/glucose transport into cell, increase glycogen synthesis
Lipids: Lipoprotein lipase releases FA from VLDL/chylomicrons
Protein: Increased protein synthesis, BCAA degradation
222
How are carbs/lipids metabolized in the brain in an absorptive state?
Carbs: Glucose used exclusively from blood glucose
Lipids: No stores of TG & albumin-bound FA do not cross BBB
223
When is the post-absorptive state?
>4 hours after eating
224
How are carbs metabolized in the liver in a post-absorptive state?
Increased glycogen degradation (glucagon)
Increased GNG from glucogenic AA, lactate, glycerol (glucagon)
225
How are lipids metabolized in the liver in a post-absorptive state?
Increased FA oxidation due to adipose TG degradation
Increased ketone synthesis for use by peripheral tissues (protein sparing)
226
How are carbs & lipids metabolized in adipose tissue in a post-absorptive state?
Carbs: less GLUT4 made = decrease in glucose metabolism
Lipids: Increased TG degradation by HSL (glucagon, epi/norepi)
FA released into blood, transported to tissues by albumin
227
How are carbs/lipids/protein metabolized in skeletal muscle in a post-absortive state?
Carbs: less GLUT4
Lipids: Up to 2 weeks - mixture of FA from adipose/ketone in liver used
3+ weeks: FA oxidation only, increased ketone levels
Protein: Up to 4-5 days - muscle broken down to send glucogenic AA to liver for GNG
Proteolysis decreases over the next few weeks
228
How are carbs & lipids metabolized in the brain in a post-absorptive state?
Carbs: glucose used exclusively for first few days from GNG
Lipids: Ketones replace glucose as main energy source after 2-3 weeks fast
229
Where does GNG primarily occur in late fasting?
Kidney
230
What AA is released from muscle and taken up by the kidney for GNG?
Glutamine
