EXAM #2: ANTIHYPERLIPIDEMICS Flashcards
Draw the overview of lipid metabolism.
N/A
Describe the structure of a lipoprotein.
- Inner core of cholesterol and cholesterol esters
- Outer phospholipid monolayer interposed with unesterified cholesterol and apolipoproteins
How does the density and structure of the lipoproteins compare to one another?
Chylomicrons= least dense HDL= most dense
Generally, the more dense means less TGs and more cholesterol
What apolipoproteins are associated with Chylomicrons?
B-48, C, E, & A
What apolipoproteins are associated with VLDL?
B-100, C, & E
What apolipoproteins are associated with LDL?
B-100
What apolipoproteins are associated with HDL?
A-I, A-II, C, E, & D
What are the functions of apolipoproteins?
1) Cofactors for enzymes in lipid metabolism
2) Ligands for receptors
3) Structural stability of lipoproteins
What is the role of NPC1L1? What drug inhibits this transporter?
Transporter responsible for the uptake of dietary cholesterol into the enterocytes
Inhibited by Ezetimibe
Outline the enterohepatic circulation of bile salts.
- Bile salts are SYNTHESIZED in the liver from cholesterol
- STORED in the gallbladder and SECRETED into the duodenum
- Most are reabsorbed but some are excreted in the feces
Bile acid resins will increases the fecal excretion of cholesterol*
What is the function of ApoB-48?
Structural integrity of lipoproteins
What is the function of ApoC-II? What happens when ApoC-II is nonfunctioning?
For dietary lipids to be removed from the circulation, lipoprotein lipase (LPL) must be activated; this requires ApoC-II
Malfunction results in v. high TG levels in the blood*
How is excess cholesterol eliminated? What organ facilitates this process?
Liver
- Cholesterol is converted into bile acids and bile salts
- Secreted into the intestines
Describe the reverse transport of cholesterol.
1) HDL contains ApoA-1 and the transporter, ABAC1, that allows HDL to accept cholesterol from peripheral macrophages
2) LCAT converts cholesterol to cholesterol esters in HDL
3) HDL is transported to the liver and binds to the hepatocyte via interactions with ApoA-1 on HDL and the SR-B1 receptor on the hepatocyte
What are the characteristics of dylipidemia?
- Elevated total and LDL cholesterol
- Low HDL
What are the goals of the clinical management of dyslipidemia?
1) Prevent acute pancreatitis
2) Prevent CAD
What are the primary/ monogenic types of hyperlipidemia?
Hyperlipidemia caused by single gene mutation
What are the polygenic-environmental types of hyperlipidemia?
Hyperlipidemia caused by a combination of genetics and environment
Outline the stages of atherosclerosis.
- Normal
- Fatty streak
- Fibrous plaque
- Occlusive atherolsclerotic plaque
- Plaque rupture/ thrombosis
What are the major risk factors for atherosclerosis?
1) Age/male gender
2) Smoking
3) HTN
4) Dyslipidemia
5) DM
6) Family history