Cholesterol Metabolism Flashcards Preview

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Flashcards in Cholesterol Metabolism Deck (26):
0

Member of _____ protein family of transporters can transport cholesterol

ATP-binding Cassette (abc)

1

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

ATP hydrolysis
Cholesterol

2

What's the ligands for LDL receptors?

apoB100 and apoE

3

LDL receptor expression is induced by ___ in the cell

Low free cholesterol level

4

Familial hypercholesterolemia is caused by mutation in ___

LDL receptor

5

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

apoE
CM
VLDL remnant

6

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

Intracellular cholesterol concentration

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.

LDL
antioxidants
Cardiovascular

8

Define reverse cholesterol transport

Transport of cholesterol from peripheral tissues back to liver for metabolism

9

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

HDL

10

HDL has 3 forms:

Pre beta HDL
HDL3
HDL2

11

Hepatic lipase hydrolyzes _____ and is activated by _____

TGs
Androgen

12

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

Androgen
Men

13

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

HDL
Cholesterol
Tangier disease

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.

Intestine

15

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

SR-BI

16

Hmg-coA reductase converts ____ to _____

Hmg-coA
Mevalonate

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

Cytosol

18

Hmg coA synthase converts ___ to ___

Acetoacetyl-coA
Hmg-coA

19

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

ER membrane

20

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

SR-AI and SR-AII

21

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

LDL
Foam cells

22

______ accounts for 2/3 of plasma cholesterol

Cholesterol ester

23

Cholesterol synthesis occurs in the _____

Cytosol

24

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

Epoxide
NADPH

25

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

HMG-coA reductase
Sterol-regulatory element (SRE)