Complex Lipids Part 1

Are bonded to other types of molecules

Complex Lipids

Consist of a core of hydrophobic lipids surrounded by amphipathic proteins, phospholipids, and cholesterol

Lipoproteins

Composed of both lipids and proteins, called apolipoproteins

LIPOPROTEINS

True or False?

The larger the LPP, the more lipid relative to CHON, therefore, lighter in density

True.

Lipoproteins have a structural motif that allows them to bind to lipids, it is called?

Amphipathic helix

Apolipoprotein that is:

– Major protein on HDL

– Measure of anti-atherogenic HDL present in plasma

Apo A-I

Apolipoprotein that is an Activator of LCAT

Apo A-I

Apolipoprotein that is the principal protein on LDL, VLDL, and Chylomicrons

Apo B

Apolipoprotein that is the ligand for LDL receptor; found on LDL, VLDL

Apo B-100

Apolipoprotein that is the main structural protein of Chylomicrons

Apo B-48

Apolipoprotein that is found in Chylomicrons, VLDL

Apo CII

Apolipoprotein that is an activator of Lipoprotein Lipase

Apo CII

Apolipoprotein that is:

– Found in those with rEmnants (Chylomicron, Chylomicron rEmnant, VLDL, IDL)

– Serves as a ligand for the LDL receptor and the chylomicron remnant receptor

Apo E

Account for the turbidity of postprandial plasma

CHYLOMICRONS

Chylomicrons readily float to the top of stored plasma and form a _________?

creamy layer

Chylomicrons are produced by the ?

intestinal cells

Deliver dietary (exogenous) lipids to hepatic and peripheral cells

CHYLOMICRONS

Account for most of the turbidity observed in fasting hyperlipidemic plasma specimens but do NOT form a top, creamy layer

VERY LOW DENSITY LIPOPROTEIN

Major carriers of endogenous (hepatic derived) triglycerides

VERY LOW DENSITY LIPOPROTEIN

Primarily formed as more TAG is removed (hepatic lipase) and more cholesterol (CETP) is added to IDL

LOW DENSITY LIPOPROTEIN

Readily taken up by cells via the LDL receptor

LOW DENSITY LIPOPROTEIN

Smallest and the most dense Lipoprotein

HIGH DENSITY LIPOPROTEIN

Type of HDL:

– Full of protein; minimal lipids yet

– Most active form in removing excess cholesterol from peripheral cells (ABCA1, ABCG1)

NASCENT/DISCOIDAL/PRE-BETA HDL

Type of HDL:

• Larger in size and richer in lipid

• May be more efficient in delivering lipids to the liver

SPHERICAL HDL

translocates cholesterol and phospholipids from cells to Apo-A1 of HDL

ABCA1 (nascent)/ABCG1 (mature)

activator of LCAT

Apo-A1

converts cholesterol to cholesteryl ester

LCAT

plasma protein that transfers cholesteryl ester from HDL to IDL and LDL in exchange for triglycerides

CETP

receptor that mediates uptake of cholesteryl ester of HDL to the liver without internalizing entire HDL

SRB1