Biochem Test Iv: Cholesterol

Front 1

what are the three critical enzymes that are needed to synthesize chylomicrons

Back 1

ACAT, DGAT, and MTP

Front 2

what is the structural protein of the chylomicron

Back 2

Apo B48

Front 3

what is the rate limiting enzyme for TG synthesis?

Back 3

DGAT

Front 4

Where are chylomicrons assembled and what protein do they have with them?

Back 4

Golgi and ER and they only have the ApoB48 when they are leaving the cell

Front 5

What apoproteins do chylomicrons pick up in the blood?

Back 5

Apo A-1, Apo CI,II,II,

Front 6

What do apoproteins do chylomicrons pick up from HDL?

Back 6

Apo C-I,II,III, Apo E and ApoA-I

Front 7

what do we call proteins that we use to form and metabolize the lipoproteins?

Back 7

apoproteins

Front 8

LCAT

Back 8

Lecithin: Cholesterol Acyl Transferase

Disk to sphere transformation

Front 9

HL

Back 9

Hepatic Lipase

Hydrolyzes TG to free fatty acids + glycerol

acts on chylomicron remnants, IDL and HDL

Front 10

ABCA1

Back 10

pumps cholesterol (and phospholipid) into HDL using ATP

Front 11

MTP

Back 11

Microsomal triglyceride transport protien

hooks triglyceride to apo B to initiate CHYLO and VLDL production

Front 12

CETP

Back 12

Cholesteryl Ester Transfer Protein

exchanges cholesterol esters in HDL for triglycerides in VLDL, chylomicrons, IDL and LDL

Front 13

Which is metabolized faster? VLDL or Chylomicrons.

Back 13

CM are metabolized in about 3 hours

VLDL are metabolized in about 36 hours

Front 14

What is Lp(a)?

Back 14

basically consists of LDL and a protein designated as (a)

Front 15

High levels of Lp(a) are a strong predictor of what?

Back 15

coronary artery disease!

Front 16

What lowers Lp(a)?

Back 16

Niacin.

Statins don't lower and sometimes increase

Front 17

Where do fatty streaks come from?

Back 17

Happens when HDL can't get the cholesterol out of the macrophages fast enough, they become foam cells which die and leave their lipids behind to form the fatty streak

Front 18

What dietary factors play the biggest role in plaque formation?

Back 18

Low intake of Omega-3, low intake of antioxdants, refined carbohydrates, trans fatty acids

Front 19

What do we take cholesterol to?

Back 19

steroid hormones, bile acids and Vit D

Front 20

T or F. Plant sterols and stanols inhibit cholesterol synthesis

Back 20

T

Front 21

how do we absorb cholesterol?

Back 21

we absorb only free cholesterol and we absorb it from mixed micelles that are formed using bile salts

Front 22

How do we absorb esterified cholesterol?

Back 22

We have to cleave off the fatty acid using cholesterol esterase. We use bile salts to form mixed micelles. Everything that isn't water soluble is put into mixed micelles

Front 23

Where did most of the cholesterol that is in the chylomicron remnant come from?

Back 23

from bile. NOT the diet.

Front 24

Do adipocytes have glycerol kinase activity?

Back 24

No

Front 25

Can cholesterol be formed in every cell in the body?

Back 25

yes except for RBC's.

Most of it is formed in the liver.

How much do we form?

Hint 25

1 gram

Front 26

Where does the carbon come from in synthesized cholesterol?

Back 26

Acetyl-CoA

What enzyme synthesizes this and what else is formed?

Hint 26

HMG-CoA Synthase found in the mitochondria.. peroxisomes might do it too

Ketone bodies

Front 27

When the liver is synthesizing fatty acids what else is it synthesizing?

Back 27

cholesterol

Front 28

what is the rate limiting enzyme for cholesterol synthesis?

Back 28

HMG-CoA REDUCTASE

Where is it found?

Hint 28

in the ER and Peroxisomes

Front 29

What are statins?

Back 29

they are a class of drug that are competitive inhibitors of HMG Co-A Reductase

Front 30

What happens with statins?

Back 30

competitively inhibit HMG-CoA Reductase which decreases cholesterol synthesis which lowers LDL in our blood.

Is that the important part?

Hint 30

no the important part is that they reduce the risk of heart attack

Front 31

What two foods have this natural statin?

Back 31

lovatstatin from Aspergillus terreus
Red yeast rice

Front 32

Do statins have any other affect on the isopentenyl pyrophosphate pathway?

Back 32

they decrease not only Cholesterol but everything else

Hint 32

They decrease inflammatory things.

Front 33

What two things predict a heart attack?

Back 33

C reactive protein and omega-3 index

Front 34

Give me some statin therapy side effects?

Back 34

Rhabdomyolysis, myopathy, bunch of other bullshit

What might help with the muscle toxicity

Hint 34

Coenzyme Q10

Front 35

What are the three theories about statins and myopathy?

Back 35

1. No cholesterol in skeletal muscle membrane makes them weak
2. disrupted muscle cell respiration
3. muscle apoptosis

Front 36

What regulates cholesterol synthesis (INhibits)?

Back 36

Cholesterol, bile salts, AMP

What stimulates?

Hint 36

Insulin, glucagon

Front 37

What are the three critical enzymes needed to synthesize chylomicrons?

Back 37

ACAT, DGAT, MTP

Front 38

Where are the chylomicrons synthesized?

Back 38

In the golgi and ER

Which Apo do they have?

Hint 38

ApoB48

Front 39

What Apo Proteins do they pick up once they get in the blood from HDL?

Back 39

Apo CI,II,III and also Apo E and Apo A-I

Front 40

Which HDL protects better than any other form?

Back 40

HDL2B which is the most mature form may protect against plaque.

Front 41

What is the only thing that can produce ApoA-II?

Back 41

the liver