MCP Flashcards
1
Q
clinical correlation: rare, inherited, mutations that encode sterolin transporters, increased phytosterols in blood and tissues, tuberous xanthomas, coronary atherosclerosis
A
sitosterolemia
2
Q
clinical correlation: low bile salts or high cholesterol, treat with laproscopic cholesystectomy
A
cholelithiasis
3
Q
bile (acids/salts) are better detergents because they are more amphipathic
A
conjugated ionized bile salts are better detergents
4
Q
bile salts lost in feces daily is (more than/less than/equal to) the bile salts made daily by liver
A
equal to
5
Q
how do statins lower cholesterol
A
they are structural analogs of HMG and competitively inhibit HMG CoA R-ase, inhibiting cholesterol synthesis
6
Q
RDS in cholesterol synthesis (substrate, product, enzyme)
A
HMG CoA to mevalonate by HMG CoA Reductase
7
Q
8 steps from mevalonate to cholesterol. Number the carbons in each intermediate
A
mevalonate has 6C > 5PPmevalonate has 6C > IPP has 5C >DMPP has 5C > GPP has 10C > FPP has 15C > squalene has 30C > lanosterol has 30C > cholesterol has 27C
8
Q
in the synthesis of cholesterol, what is the purpose of release of pyrophosphate
A
makes reactions irreversible
9
Q
in the synthesis of cholesterol, what is the purpose of phosphorylation
A
makes intermediates more soluble in water
10
Q
which intermediates in synthesis of cholesterol need carrier proteins
A
squalene, lanosterol, cholesterol
11
Q
(insulin/glucagon) upregulates HMG CoA R-ase activity
A
insulin (HMG CoA R-ase=synthesis of cholesterol=anabolic)
12
Q
(phosphorylation/dephosphorylation) INACTIVATES HMG CoA R-ase
A
phosphorylation
13
Q
high cholesterol (increases/decreases) HMG CoA R-ase activity
A
decreases (binds sterol sensing domain on the enzyme which triggers ubiquitination>proteasomal degradation, also binds sterol sensing domain on SCAP so SCAP-SREBP2 can’t migrate to golgi to cleave SREBP to increase txn)
14
Q
Apo _: Structural protein (HDL); LCAT activator; Involved in RCT; ligand for ABCA1 and SR-B1
A
A-I
15
Q
Apo _: structural protein HDL, inhibits LCAT,
A
A-II
16
Q
Apo _: structural protein (VLDL, LDL), VLDL assembly, LDLR binding, one copy for each VLDL
A
B-100
17
Q
Apo _: structural protein (LDL, VLDL), VLDL assembly, LDLR binding, produced in intestine, chylomicron metab
A
B-48
18
Q
Apo _: can be exchanged freely among lipoprotein particles, important for TG metab bc they interfere with recognition of ApoE by LP receptors or displace ApoE from lipoproteins
A
C’s
19
Q
Apo C (I/II/III): LCAT activator
A
I
20
Q
Apo C (I/II/III): lipoprotein lipase activator
A
II
21
Q
Apo C (I/II/III): inhibits lipoprotein lipase
A
III
22
Q
Apo E (2/3/4): normal
A
3 edited
23
Q
Apo E (2/3/4): risk for type III hyperlipidemia
A
3
24
Q
Apo E (2/3/4): Alzheimer’s
A
4
25
Apo _: modulates thrombosis/thrombolysis
(a)
26
(DRI/RDA): defined as the amount sufficient to meet the nutrient requirement of 97-98% of healthy individuals in a given group
RDA = recommended daily allowance, varies for different populations
27
two water soluble vitamins
B and C
28
deficiencies arise more rapidly with (water/lipid) soluble vitamins
water solulbe, since they are excreted efficiently
29
Vit _: functions in visual cycle, antioxidant, retinoic acid acts as a hormone
A
30
Vit _: deficiency causes night blindness, xeropthalmia, follicular hyperkeratosis, anemia (despite normal iron intake), poor growth in children, increased susceptibility to cancer
A
31
three groups susceptible to Vit A def
poor, malnourished, premature babies
32
Vit _: functions in maintaining bone, calcium homeostasis, acts as a hormone
D
33
Vit _ def: rickets, osteomalacia, increased susceptibility to breast and other cancers, diabetes, and infection
D (toxic levels of Vit D can lead to high levels of calcium and bone loss--rare)
34
three groups susceptible to Vit D def
poor, elderly, alcoholics
35
Vit _: functions in localization of enzymes required for blood clotting, helps catalyze add'n of gamma-carboxyglutamate to clotting enzymes
K
36
Vit _ def: results in easy bruising, bleeding, hemorrhage
K
37
four groups susceptible to Vit K def
NEWBORN INFANTS, patients on long term antibiotics, elderly, pts with defects in fat absorption
38
why are newborns so susceptible to Vit K def
lack intestinal bacteria that makes vitamin K, and deficiency can lead to brain bleed. Vitamin K shot now given at delivery (prophylactic measure)
39
why are people on long term antibiotics susceptible to Vit K def
antibiotics kill intestinal bacteria that make vit K
40
Vit _: functions as antioxidant, protects membranes from damage, prevents oxidation of LDL
E
41
Vit _ def: CVD, neurological symptoms
E
42
Vit _: cofactor for oxidases
involved in collagen
formation, required for synthesis of steroids in stress
response (response to
trauma), aids absorption of iron, has antioxidant
activity
C
43
Vit _ def: mild causes bruising and immunocompromise, severe causes scurvy
C
44
name disease: decreased wound healing, osteoporosis, hemorrhage, anemia, fatigue
scurvy
45
two groups susceptible to Vit C def
smokers, ppl w/ poor diet
46
severe stress or trauma rapidly reduces serum Vit _
C
47
In addition to smoking, long-term treatment with aspirin,
oral contraceptives, and corticosteroids can decrease
serum vitamin _
C
48
corkscrew hairs and pinpoint hemorrhages are characteristic of ____ (dz)
scurvy, also severe periodontal dz
49
name B1
thiamine
50
name B2
riboflavin
51
name B3
niacin
52
name B5
pantothenic acid
53
name B6
pyridoxine
54
name B9
folate
55
name B12
cobalamin
56
name the hematopoietic B vitamins (two)
B9 and B12
57
name the energy releasing B vitamins (six)
B1, B2, B3, biotin, B5, B6
58
symptoms of def in energy releasing B vitamins show up first where
in rapidly dividing tissues--Nervous system also affected because of high
energy demand:
Peripheral neuropathy—tingling of extremities
Depression, confusion
Lack of coordination
Malaise
59
Vit _: required cofactor for several enzymes in energy metabolism, critical in nervous system
B1 (TPP)
60
```
name disease: • Moderate/severe thiamine deficiency,
most commonly seen in chronic
alcoholics
• Characterized by mental disturbance,
unsteady gate, and uncoordinated eye
movements
• Occasionally congestive heart failure
```
Wernicke-Korsakoff syndrome
61
name disease: Very Severe thiamine deficiency: 19th century
| Japan- switch to polished rice induced disease
Beri Beri
62
```
Vit _: Precursor
of FAD and FMN, key
coenzymes for redox
reactions involved in
energy metabolism
```
B2
63
```
Vit _ def: —rash
around nose,
inflammation of mouth
and tongue, burning
and itchy eyes, light
sensitivity
```
ariboflavinosis B2
64
```
Vit _: Precursor
of NAD and NADP
coenzymes important in
redox reactions of
energy metabolism
• Given to patients with
hyper-cholesterolemia
or hypertriglyceridemia
(high doses)
```
B3
65
Vit _ def: pellagra
B3 niacin
66
name disease: dermatitis,diarrhea,
and mental symptoms
(confusion, memory
loss, mania)
Pellagra
67
group susceptible to B3 def
People with corn or
| millet based diets
68
Vit _: coenzyme for several carboxylases. Def is rare but can be caused by eating a lot of raw eggs
biotin
69
```
Vit _: Required for the
synthesis of CoA
CoA is a coenzyme for
up to 70 different
enzymes
Required for TCA
cycle and metabolism
of all fats and
proteins
```
B5
70
Vit _: Required for glycogen
breakdown,and
synthesis of GABA
and heme
B6. Also precursor of pyridoxal phosphate PLP enzyme cofactor
71
group susceptible to B6 def
patients treated with TB drugs
72
```
Vit _ def: Mild—irritability,
nervousness,
depression
Severe—peripheral neuropathy,
convulsions, decreased
glucose tolerance,
hyperhomocysteinemia
(cardiovascular risk),
anemia
```
B6
73
Vit _: functions as precursor of THF, co enzyme involved in generating precursors for DNA and protein synthesis
B9 folate
74
Vit _ def: neural tube defects in newborns of deficient mothers
--macrocytic anemia, hyperhomocysteinemia (cardiovascular risk)
B9 folate
75
five groups susceptible to folate B9 def
pregnant women, elderly, alcoholics, patients with long-term drug treatments, genetic polymorphisms in folate metab
76
folate supplementation during pregnancy can prevent
neural tube defects
77
Vit _: functions as coenzyme in methionine synthesis and in conversion of methylmalonyl CoA to succinyl Coa, needed in folate metab
B12 cobalamin
78
Vit _ def: pernicious megaloblastic anemia with demyelination
B12 cobalamin (need intrinsic factor)
79
three groups susceptible to B12 cobalamin def
elderly, patients with malabsorption dz, long-term vegetarians
80
mineral _: functions as a major component of bone, signaling, coagulation, muscle contraction, neurotransmission
calcium
81
mineral _ def: muscle cramps, osteoporosis. severe: rickets
calcium
82
three groups susceptible to calcium def
children, adult women, elderly
83
mineral _: essential for enzymes using ATP as substrate, present at high levels in bone
magnesium
84
mineral _ def: weakness, tremors, cardiac arrhythmia
magnesium
85
two groups susceptible to magnesium def
alcoholics, patients taking diuretics/severe vomiting and diarrhea
86
mineral _: major component of bone, constituent of nucleic acids and membrane lipids, required in all energy producing reactions
phosphorus
87
mineral _ def: rare, can result in rickets, muscle breakdown, weakness, seizure
phosphorus--abundant in food supply
88
mineral _: functions in O2/CO2 transport, oxidative phosphorylation, cofactor in cytochromes, redox
iron
89
mineral _ def: microcytic hypochromic anemia, decreased immunity
iron
90
four groups susceptible to iron def
children, menstruating women, pregnant women, elderly
91
Reduction of Fe3+ to Fe2+ is promoted by vitamin _ in
| diet. (Vitamin _ deficiency causes mild anemia.)
C
92
Low pH in stomach helps release Fe_+ from ligands and makes it bioavailable.
3+
93
iron is (free/escorted) in circulation and cells
escorted bc of potential for redox damage
94
___ (mineral) deficient anemia: microcytic, small, pale RBCs, less Hb is produced
iron deficient
95
name disease: long term iron toxicity
hemochromatosis
96
name dz: --iron overload leads to iron deposits in multiple
tissues. Leads to compromised liver, pancreatic, and cardiac function.
--ultimately can compromise mitochondrial
function leading to lactic acidosis
hemochromatosis
97
most common cause of death due to toxicity in
| children under 6, comes from consumption of adult supplements
acute iron overdose in children
98
mineral _: assists iron absorption thru ceruloplasmin, cofactor for enzymes required in collagen synthesis, fatty acid metab, elimination of ROS
copper
99
mineral _ def: rare. anemia, hypercholesterolemia, fragility of large arteries, bone demineralization and demyelination
copper
100
two groups susceptible to copper def
Menkes' genetic syndrome, pts consuming excessive zinc
101
____ disease comes from mutations in
| Cu transporter ATP7A
Menkes
102
```
Need to transport __
into Golgi to supply __
To enzymes like
Lysyl oxidase. These enzymes are
secreted without
__ if ATP7A is
missing
```
copper
103
____disease comes from mutations in ATP7B, a
| relative of ATP7A, but results in copper overload.
Wilson's
104
____ disease: Copper is not sequestered properly, and accumulates in
liver with severe liver and nervous system symptoms.
Results in liver failure and liver cancer.
Wilson's
105
mineral _: cofactor for over 300 metalloenzymes, plays a structural role in many proteins
Zn
106
```
mineral _ def: Poor wound healing, dermatitis,
reduced taste acuity,
poor growth and
impaired sexual
development in children
```
Zinc
107
four groups susceptible to Zn def
alcoholics, elderly, people with malabsorption or kidney disease
108
earliest symptom of Zn def
dermatitis
109
mineral _: component of chromodulin which facilitates insulin binding to its receptor
chromium
110
mineral _ def: impaired glucose tolerance from reduced insulin effectiveness
chromium
111
one population susceptible to chromium def
those with impaired glucose tolerance
112
mineral _def: goiter, hyper/hypo thyroidism
iodine
113
mineral _: incorporated into T3 and T4, regulates BMR
iodine
114
Low [I] stimulates increased thyroid stimulating
hormone, results in enlarged thyroid characteristic
of ____
goiter
115
mineral _: component of antioxidant enzymes (glutathione peroxidase), component of deiodinase enzymes involved in T3/T4 metab
selenium
116
```
mineral _ def: Keshan
disease (in areas with
little __in soil)—
cardiomyopathy and
cretinism
```
selenium
117
mineral _ is a cofactor in arginase, pyruvate carboxylase,
| superoxide dismutase
manganese
118
mineral _ is a cofactor in xanthene oxidase
molybdenum
119
mineral _ is incorporated into bones and teeth, strengthening them
fluoride
120
boron is involved in ___formation
bone
121
mineral _ is a component of amino acids and used in certain post-translational modifications
sulfur
122
children are most susceptible to what two mineral deficiencies
iron and calcium
123
teenagers are most susceptible to what kind of vitamin and mineral def
calcium, magnesium, Vitamin A, C, B6
124
women are most susceptible to what five vitamin and mineral def
iron, calcium, magnesium, B6, folate
125
elderly are most susceptible to what five vitamin and mineral def
B6, B12, D, Zn, chromium
126
alcoholics are most susceptible to what three vitamin/mineral deficiencies especially
folate, B6, thiamine. but multiple deficiencies
127
which apoprotein is only made in the intestine
B48
128
density of chylomicron is (proportional/inversely proportional) to size
inversely proportional to size. more proteins:lipids = more dense
129
nascent (VLDL/chylomicron): B100 on surface
VLDL
130
nascent (VLDL/chylomicron): B48 on surface
chylomicron
131
HDL supplies __ and __ apoproteins to chylomicrons and VLDL
C II and Apo E
132
When VLDL loses its CII and Apo E to HDL, it becomes ___ and is endocytosed by liver
LDL
133
before entering the capillaries, VLDL and chylomicrons have (more/less) TAG and (less/more) cholesterol esters
more TAG, less cholesterol esters. After the capillary, more cholesterol esters than TAG.
134
function of ___: provide cholesterol to peripheral tissues and return it to liver
LDL
135
CURL=
compartment for uncoupling receptor and ligand (LDL receptor and LDL in clathrin coated pit)
136
the LDL binding region on LDL receptor is rich in ____ (aa) residues
cysteine
137
which domain of the LDL receptor associates with clathrin pit and initiates endocytosis
6, the cytosolic domain
138
which domain of the LDL receptor is the alpha helix through the bilayer
5
139
which domain of the LDL receptor makes the binding domain more accessible to LDL by moving it away from the membrane
3 and 4
140
which domain of the LDL receptor undergoes a conformational change in low pH, causing release of LDL from the receptor
2
141
__: formed by addition of lipids to Apo A I
HDL
142
__: serves as a circulating supplier of Apo C II and Apo E
HDL
143
shape of nascent HDL
discoid--contains phospholipids and Apo A, C, E. Takes up cholesterol from peripheral tissues and returns it to liver
144
enzyme in reverse cholesterol transport
LCAT
145
when macrophages consume excess oxidized lipoproteins, they become:
foam cells
146
foam cells release ____ and ____ which cause the migration of myofibroblasts to the intima where they proliferate and take up lipid
growth factors and cytokines
147
not produced in ob/ob mice (leptin/leptin receptors)
leptin--from fat tissue
148
not produced in db/db mice (leptin/leptin receptors)
leptin receptors--hyth
149
lysyl oxidase is involved in the cross-linking step in Type _ collagen
I
150
appetite hormone released by empty stomach (leptin/ghrelin/CCK)
ghrelin
151
(visceral/peripheral) obesity is characteristic of metabolic syndrome
visceral (android)
152
where is the leptin receptor synthesized
hyth
153
niacin (has/does not have) significant stores in tissues
has
154
prolyl and lysyl hydroxylase utilize vitamin _ as a cofactor
C (ascorbate)
155
which of the following are required for collagen biosynthesis: (lysyl/prolyl/hydroxylase)
all three
156
leptin release normally (increases/decreases) with body mass
increases
157
UCP1 promotes adaptive thermogenesis in the presence of _____ (substrate for symporter)
free fatty acids
158
Appetite-inhibiting signal released from endocrine cells associated with the colon and distal small intestine that acts on cells in the hypothalamus: (CCK/PYY3-36)
PYY3-36
159
required for collagen biosynthesis: (Vit C/copper/iron/biotin)
Vit C, copper, iron
160
Vit B_ is required for biosynthesis of B_ from tryptophan
Vit B2 required for synthesis of B3
161
Vit B_ is required for transformation of inactive B6 to active B6
B2
162
formation of CoA requires _____ acid, a B-complex vitamin
pantothenic
163
in metabolic syndrome, which are elevated: (insulin in blood/triglyceride in blood/HDL in blood/blood pressure)
insulin, triglyceride, blood pressure. HDL is low
164
name the B vitamin that: reverses pellagra, co-factor of redox, no significant stores in tissues, used in conjunction with statins for tx of hypercholesterolemia
niacin B3
165
def in which can correlate to anemia: (B12/B2/folic acid/iron/copper)
all except B2 (so: folic acid, B12, iron, copper)
166
lysyl (oxidase/hydroxylase) contributes to cross linking in Type I collagen
oxidase
167
MOI G6PD deficiency
X linked
168
is electrophoretic mobility of G6PD related to activity of enzyme
no
169
what is the evolutionary benefit of G6PD def
protects against malaria
170
what are Heinz bodies in G6PD def
insoluble precipitates that become attached to cell cytoskeleton > RBC gets destroyed in spleen
171
(superoxide/NADP+) is produced in the phagosome as a result of NADPH oxidase
superoxide
172
(superoxide/NADP+) is produced in the cytosolas a result of NADPH oxidase
NADP+
173
why do normal phagocytes reduce the dye NBT only after they have been activated
superoxide reduces NBT
174
what molecular moiety donates an electron directly to O2 in the respiratory burst oxidase reaction
cyt b558
175
in what cells is myeloperoxidase found
neutrophils
176
what rxn is catalyzed by myeloperoxidase
H2O2 to HOCl
177
what is the effect of opening the Permeability Transition pore on the IMM
dissipates membrane potential > can't make ATP > necrotic cell death
178
how do chelators that bind iron or copper tightly prevent reperfusion injury
prevent the Fenton reaction, can't make OH radical
179
allopurinol inhibits xanthine oxidase, which inhibits formation of which free radical
superoxide
180
hydroxyl radicals (are/aren't) effectively scavenged by SOD and catalase
aren't
181
enzyme that converts hydrogen peroxide to hypochlorous acid in the phagosome.
myeloperoxidase
182
Produced in the oxidation of hemoglobin by molecular oxygen: (superoxide/H2O2/OH radical/HOCl)
superoxide
183
substrate for catalase: (superoxide/H2O2/OH radical/HOCl)
H2O2
184
produced by myeloperoxidase (superoxide/H2O2/OH radical/HOCl)
HOCl
185
(superoxide/H2O2/OH radical/HOCl): generated in the nonenzymatic reduction of H2O2 by Fe2+
hydroxyl radical
186
(superoxide/H2O2/OH radical/HOCl): generated by the decomposition of peroxynitrite (ONOO + H+ --> ONOOH --> OH + NO2
hydroxyl radical
187
which are least dense (chylomicrons/VLDL)
Chylomicron
188
During biosynthesis of VLDL in the liver, a large fraction of the total cholesterol in the particle is in the free form because: (ACAT levels are low/lysosomal cholesterol esterase activity is elevated)
ACAT levels are low
189
When cholesterol levels in the cell are (low/high), S1P protease will be inactive and cleavage of SREBP will not proceed
high
190
When cells previously growing in a cholesterol-free environment are exposed to excess LDL cholesterol, SCAP will (remain in/exit) the ER
remain in
191
Which lipoprotein has the following approximate composition (by weight), 50% cholesterol/cholesterol esters : 10% triacylglyerols : 20% protein? (HDL/LDL)
LDL
192
reverse cholesterol transport would be reduced under (high LDL levels/Apo AI deficiency)
Apo AI def
193
Apo __ is a risk factor for atherosclerosis because it accumulates to higher levels in VLDL than other alleles do
E2
194
(VLDL/LDL) has a half life in serum of 3 days
LDL
195
Both pancreatic and lipoprotein lipases (require CII for efficient binding of enzyme to substrate/hydrolyze ester bonds)
hydrolyze ester bonds
196
Compared to newly assembled chylomicrons, chylomicron remnants have a (lower/higher) ratio of TAGs to cholesteryl esters
lower
197
Compared to newly assembled chylomicrons, chylomicron remnants have a (lower/higher) density
higher
198
(Long-chain fatty acids/TAGs) used by the heart as fuel may be:
long chain fatty acids
199
When cholesterol levels in the cell are (low/high), S1P protease will be inactive and cleavage of SREBP will not proceed
high
200
obesity is a (minor/major) risk factor for atherosclerosis
minor
201
synthesis of cholesterol requires _ HMG-CoA's
6
202
A decrease of cholesterol-7a-hydroxylase (CYP7A1) activity would (increase/decrease) bile acid production
decrease
203
A decrease in cholesterol-7-hydroxylase (CYP7A1) activity would (increase/decrease) risk for atherosclerosis
increase
204
(VLDL/LDL/HDL): approx 50% protein by weight
HDL
205
(hepatic/lipoprotein) lipase hydrolyzes triglycerides in VLDL remnants
heptaic lipase
206
(LCAT/lipoprotein lipase) involves hydrolysis of TG
lipoprotein lipase
207
Apo _ is the ligand for LDL uptake through the LDL receptor
Apo B-100
208
HMG-CoA reductase: (phosphorylated/unphosphorylated) enzyme is more active
unphos
209
Type III hyperlipoproteinemia is: associated with presence of Apo _
E2
210
Type III hyperlipoproteinemia is associated with (reduced/elevated) TG
elevated
211
Type III hyperlipoproteinemia is associated with abnormal migration of (LDL/HDL)
LDL
212
Type (III/II) hyperlipoproteinemia is associated with a mutation in the LDL receptor
II
213
heavy drinking: insulin levels go (up/down)
down
214
As large amounts of ethanol are metabolized, serum (glucose/lactate) concentration goes down
glucose
215
alcohol dehydrogenase is found in the (ER/cytoplasm/mit) of liver cells
cytoplasm
216
Result of acat def (increase/decrease) in amount of cellular cholesterol esters
Decrease
