Chapter 22

What is a micelle?
  on the outside, all  on the inside

Hydrophilic exterior displays
aqueous-soluble molecules:  ,  , and  

Hydrophobic center contains
the lipid cargo:  , , and  
(AKA  )

Hydrophilic exterior displays aqueous-soluble molecules:
•  
•  (act in
  and provide
 )

Hydrophobic center
contains the  cargo:
•  
•  

As diameter  , the density of lipoproteins  .

What are the 4 types of plasma lipoproteins?
1.  
2.  
3.  
4.  

HDL cholesterol is often referred to as  cholesterol. HDL picks up   in your blood and takes it back to your  where it's broken down and removed from your body.

Phospholipids and cholesterol are  .

Triacylglycerol and cholesterol ester are  .

When though cholesterol are most non-polar, they have an  that gives them polarity

Apoproteins

Apolipoproteins plays a role in  polarity

Cholesteryl ester is more hydrophobic than  

Apolipoproteins act as   for interaction with  

Apolipoproteins serve as  

Apolipoproteins form part of structure of 

 is thought to have a role in chylomicron metabolism and may also act as a regulator of satiety and glucose homeostasis, making it a potential therapeutic target for the treatment of diabetes and obesity, while  is believed to be an important factor in human neurodegenerative disorders.

Apo A (I, II & IV)
Associated with  

Apo B (-48 & -100)
 

Apo C (I, II, III)
Associated with   and  

Apo D
Associated with   &  

Apo E (II, III, IV)
– Associated with  

Apo (a)
Associated with 

Apo M
Associated with  

Hepatic lipase (HL)
found in  ,   and  
Function:  

Lipoprotein lipase (LPL)
found in   and  muscle

Lecithin–cholesterol acyltransferase (LCAT)
made in  , found on  
(lecithin is  )

ATP binding cassette (ABCA1 / ABCGs) Function
Rate-limiting factor of  assembly
and is regulated by   and   factors

What are two important transporters?
 and  

What type of lipids need to be broken down?

Lipoproteins lipase found in   and  interacts with  and  via  . It breaks down a triglyceride into 3 fatty acids and a glycerol.

Hepatic lipase is found in  and and in addition to its enzyme activity,
hepatic lipase also acts to , mediating   with receptors such as the   and  .

Lecithins are
  containing
 .

LCAT cleaves the
  from
lecithin to add to
cholesterol & form
 
(neutralizing the only
  on cholesterol)

The byproduct of LCAT
esterification of cholesterol,
 , is named for its
ability to disrupt membranes
(observed  ).

Intermolecular polarity plays an
important role in the orientation of
_____.

CHolesteryl ester is the MOST  IN LIPOPROTEIN

Apolipproteins form part of the  of the lipoprotein, for example,  

Apolipoproteins serve as enzyme  

C-II is the cofactor for

A-I is the cofactor for

Apo A-II and Apo C-III are the enzyme inhibitors of

Apo C-1 is inhibitor for  

Apolipoproteins are  for interaction with lipoprotein receptors in tissues

  is thought to have a role in   and may also act as a
regulator of satiety and glucose homeostasis, making it a potential therapeutic
target for the treatment of diabetes and obesity

 is believed to be an important factor in human neurodegenerative disorders.

Cholesteryl ester transfer
protein (CETP) shuttles
various lipids between
lipoproteins,
resulting in the net transfer
of   from
atheroprotective, 
to atherogenic, 

Inhibition of   raises
HDL cholesterol and may
potentially be used to treat
cardiovascular disease.

ABC Proteins are   that mediates the transport of
   , and other  from cells To lipid-depleted  
apolipoproteins.

ABCA1 is essential for, and represents the  step of,
the formation of   .

ApoE is in what? Function?
•  ,   &  
-   particle uptake

ApoCII is in what? Function?
- 
-  and  

ApoA is in what? Function?
 
-  uptake & particle recycling

What 3 apo proteins are involved in receptor-mediated Apos?

Which molecules are found in the cell or coat of lipoproteins?

Exogenous pathway for fats
Eat fatty acids, then  , then going to the  
( ,  , and  )

Endogenous pathway for fats
1. Liver makes  to send out fats ( and  ) and the we have   and  .
2. There is a continous breakdown to smaller lipid units down to   and  

 drain into the lymph and are picked up by lymph vessels

  lipoproteins are made by a hepatic cell

After a fatty meal,
many  
are dumped into the
 
and   can be easily
visualized as being
  due to
the large particles
scattering light!

Chylomicrons
carry  (Ex.   and  )
from the gut.
They are synthesized in the   and delivered via the thoracic
duct (lymph) into the venous
circulation. [ ]

In capillaries of   and  ,
lipoprotein lipase (LPL) recognizes the
 , and removes  

Remnant chylomicrons, depleted of 
and  , (and relatively enriched in
cholesterol), are taken up by the liver,
where the remaining TAGs and
cholesterol are incorporated into  

Triacylglycerols has high/low VLDL? IDL? LDL

CHolesterul esters has high lower VLDL? IDL? LDL?

What are the major apolipproteins in VLDL?

What are the major apolipoproteins of IDL?

What are the major lipproteins of LDL?

If you have a very fatty diet or incufficent HDL?

High Density Lipoprotein is synthesized in the liver as an  ,  , and
 

HDL upon release from the liver into the blood,
acquires   from peripheral tissues via
  and  

The unesterified cholesterol of HDL is esterified by  

HDL also acts as a reservoir for   and  ,
donating them to   and  as
they are encountered in the circulation.

HDL is recycled in the liver by binding   (LDL
receptor) or the  (scavenger receptor type
B1)

Lipoprotein(a) is a a variant of LDL with an additional protein, apo(a),
linked by  to  .

Lipoprotein(a) has been shown that in  , it is an independent risk factor for  and consequent  and 

The sequences of lipoprotein a is very similar to that
of   (the precursor of  , an enzyme
that  ).

The significance of observations regarding Lipoprotein a is not clear, however,
the ability of apo(a) to interfere with   would
be consistent with its structural relationship to
 .

Patients possessing the   have higher incidence of
Alzheimer disease. It binds more avidly to
 found in neuritic plaques.