Lipids Flashcards
1
Q
chylomicrons
A
- lowest density lipoproteins
- 90-96% TG
- Apo B-48, E, C-11
2
Q
VLDL
A
- still very low density
- 60% TG
- Apo B-100, E, C-11
- TG is surrogate for # of VLDL particles
3
Q
LDL
A
- Primary atherogenic class in body-primary determinant of risk
- more dense
- predominant for cholesterol (50%)
- Apo B-100
4
Q
HDL
A
- smallest, most dense
- mostly protein and cholesterol
- Apo A-1 and A-11
5
Q
Apo-C
A
activates lipoprotein lipase
6
Q
Apo-E
A
remnant receptor ligand
7
Q
Apo-B 100
A
From liver
8
Q
Apo-B48
A
from intestine
9
Q
Statins
A
- HMGCoA Reductase inhibitor
- Major effect-lower LDL-C 20-60%; modestly lower TG and increase HDL-C
- pleotropic effects-inhibition of isoprenylation of small GTP-binding proteins
- SE: myalgia, myopathy, abnormal liver fxn tests
- Pregnancy class X
10
Q
Statin mechanism
A
- Inhibit HMGCoA reductase-> necessary for synthesizing cholesterol
- reduce intrahepatic cholesterol pool-> increase hepatic LDL receptors and remove LDL from bloodstream
11
Q
Bile Acid binding Resins
A
- decrease LDL-C 15-30%, modest increase in TG and HDL-C
- Block absorption of bile salts in terminal ileum-> decreases intrahepatic pool and increases receptor
- May produce compensatory increase in HMGCoA R-best w/ statin
- SE: abdominal discomfort and constipation, decrease absorption of other drugs, decrease absorption of fat soluble vitamins
12
Q
Azetidinones
A
- Decrease LDL-C by 14-20%, small decrease in TG, small increase in HDL-C
- blocks absorption of cholesterol in small intestine by inhibiting NPC1L1 protein->decrease intrahepatic pool
- well tolerated
13
Q
Apo A1
A
combines w/ free cholesterol to make nascent HDL
14
Q
LCAT
A
esterifies cholesterol to make mature HDL
15
Q
SR-B1 receptor
A
mature HDL receptor in liver
16
Q
CETP
A
- cholesterol ester transfer protein
- acts when TG levels high
- transfers TG into HDL and cholesterol esters into CM/VLDL/LDL
17
Q
arcus corneus
A
- gray stripe on outer iris
- signifies high TG, low HDL
18
Q
xanthelasmas
A
- seen in familial hypercholesteremia
- cholesterol deposits on eyelid
19
Q
eruptive xanthoma
A
- in chylomicronemia syndrome
- looks like chicken pox on butt
- seen on surfaces that rub against things
- fat eruptions through skin
20
Q
lipemia retinalis
A
- fat globules inside vessels (streaks(
- in chylomicronemia syndrome
21
Q
Familial hypercholesterolemia
A
- genetically deficient/defective LDL receptor
- autosomal dominant
- tendon xanthoma, xanthelasmas, arcus corneus
- heterozygotes-cardiac events- men 20s, women 30s
22
Q
Familial defective Apo B-100
A
- mutation in gene for ApoB-100 leads to poor LDL binding to receptors
- functionally similar to FH
- LDL easily oxidized
23
Q
Familial Combined Hyperlipidemia
A
- varying patterns of LDL-C and VLDL-C in families
- high levels of ApoB-100 lead to to high levels of VLDL and LDL (hyperapobetalipoproteinemia); 1/3 also have LPL abnormality
- xanthelasmas, arcus corneus, HTN, DM II, obesity
24
Q
Familial hypo alpha lipoproteinemia
A
- autosomal dominant defects in ABC A1
- low HDL
- cataracts, arcus corneus
- increased risk of CHD
25
Niacin
- nicotinic acid, vitamin B3
- mechanism: reduce lipolysis from adipocytes; reduce VLDL synthesis by inhibiting DGAT2; reduce ApoA-1 catabolism
- SE: flushing and itching (tx-aspirin), abdominal pain, ulcers, insulin resistance, hyperglycemia, hepatotoxicity, gout, myalgia/myopathy
- do not use if pregnant
26
Fibrates
- mechanism: activates PPAR-a-> increase synthesis of ApoA- I and II; activates LPL and decrease ApoCIII (LPL inhibitor); stimulates hepatic FA uptake and catabolism by B-oxidation-> decrease TG synthesis
- SE/precautions: abdomial pain, gall stones, increase creatinine-DNU kidney ds, myalgia/myopathy, liver ds, pregnancy
27
Omega 3 FAs
- reduce TG, increase HDL, LDL may increase or stay
- mechanism: inhibit DGAT, reduce lipolysis, stimulate hepatic FA catabolism by B-oxidation-> decrease TG synthesis
- SE: eructation, flatulence, abdominal pain, bruising/bleeding
