Cholesterol Metabolism

Question 0

ABC transporter such as ABCG5 and ABCG8 couple _____ to transport of unwanted or excessive _____ and plant sterols from enterocyte back into gut lumen.

Answer 0

ATP hydrolysis

Cholesterol

Question 1

Member of _____ protein family of transporters can transport cholesterol

Answer 1

ATP-binding Cassette (abc)

Question 2

What’s the ligands for LDL receptors?

Answer 2

apoB100 and apoE

Question 3

LDL receptor expression is induced by ___ in the cell

Answer 3

Low free cholesterol level

Question 4

Familial hypercholesterolemia is caused by mutation in ___

Answer 4

LDL receptor

Question 5

LDL receptor- related protein (LRP) ‘s ligand is _____, and binds to ___ or ____

Answer 5

apoE
CM
VLDL remnant

Question 6

LDL receptor- related protein (LRP) is not affected by increase in _____

Answer 6

Intracellular cholesterol concentration

Question 7

Superoxide radicals, nitric oxide, hydrogen peroxide and other oxidants promotes the oxidation of ____, therefore ______ such as vitamin c, vitamin E and carotenoids offer protection against _____ diseases.

Answer 7

LDL
antioxidants
Cardiovascular

Question 8

Define reverse cholesterol transport

Answer 8

Transport of cholesterol from peripheral tissues back to liver for metabolism

Question 9

_____ is a major player in the process of reverse cholesterol
transport

Answer 9

HDL

Question 10

HDL has 3 forms:

Answer 10

Pre beta HDL
HDL3
HDL2

Question 11

Hepatic lipase hydrolyzes _____ and is activated by _____

Answer 11

TGs

Androgen

Question 12

_____ activates HL, promoting at conversion to less mature HDL. This accounts for the lower HDL level
In _____

Answer 12

Androgen

Men

Question 13

Defective ABCA1 reduces ____, and accumulate _____ in liver and peripheral tissue, cause _____ disease

Answer 13

HDL
Cholesterol
Tangier disease

Question 14

Ezetimibe is a drug that blocks cholesterol absorption in the ______, causing a portion of dietary cholesterol to be carried into fece rather than chylomicron.

Answer 14

Intestine

Question 15

Mature HDL is primarily cleared through ______ expressed in many cell types

Answer 15

SR-BI

Question 16

Hmg-coA reductase converts ____ to _____

Answer 16

Hmg-coA

Mevalonate

Question 17

Hmg-coA synthase used in cholesterol synthesis is present in _____ and is distinct from the mitochondrial hmg-coA synthase involved in ketone body generation

Answer 17

Cytosol

Question 18

Hmg coA synthase converts ___ to ___

Answer 18

Acetoacetyl-coA

Hmg-coA

Question 19

Hmg-coA reductase resides on the ______ with its n-terminal catalytic domain facing the cytosol.

Answer 19

ER membrane

Question 20

While SR-BI is used primarily for HDL, ____ are present of macrophages

Answer 20

SR-AI and SR-AII

Question 21

The continued uptake of oxidized ____ particle by the SR-AI and SR-AII will results in the formation of ____

Answer 21

LDL

Foam cells

Question 22

______ accounts for 2/3 of plasma cholesterol

Answer 22

Cholesterol ester

Question 23

Cholesterol synthesis occurs in the _____

Answer 23

Cytosol

Question 24

Cycliczation of squalene to lanosterol is preceded by ___ formation involve oxygen and ____

Answer 24

Epoxide

NADPH

Question 25

SREBP enhance the transcription of ____ by binding to the _____ upstream of the gene

Answer 25

HMG-coA reductase

Sterol-regulatory element (SRE)