Lipid Metabolism Flashcards
What are cells that store fatty acids called?
Adipocytes
What are the 3 Fat sources?
Diet
Stores in adipocytes
De novo synthesis in liver
What are bile salts?
Emulsifiers that have a hydrophobic face to interact w/fats, allowing absorption
What is a bile salt generated from?
Cholic acid
What is Orlistat?
Lipase inhibitor - prevents digestion of fats
How do fats enter the circulation?
Triacylglycerols packaged into chylomicrons which enter the lymph, then enter circ.
How does the caloric yield of fatty acids compare to glucose?
Roughly double.
What happens in ß-oxidation
2 carbons are removed from the fatty acid at a time in the form of Acetyl-CoA
What is required to transfer the Fatty Acyl-CoA into the mitochondrial matrix?
Carnitine Shuttle:
Acyl group is coupled to Carnitine by Carnitine Acyltransferase.
Translocase moves Acyl carnitine into matirx
What are the two types of Carnitine acyltransferase, and where are they found?
Carnitine acyltransferase I/II
I: Cytoplasmic side
II: Matrix side
What are the four reactions of the ß-oxidation cycle?
- Fatty acyl-CoA oxidised producing FADH2
- Hydrolysed with H2O
- Oxidised producing NADH
- ß-ketothiolase removes acetyl group and reacts with HS-CoA producing Acetyl-coA
What are the products of one turn of the ß-oxidation cycle?
FADH2
NADH
Acetyl-CoA
Fatty acyl-CoA 2 carbons shorter.
How is a Fatty acyl-CoA generated for ß-oxidation?
Fatty acid + ATP +HS-CoA
–> w/Acyl-CoA Synthetase
Fatty Acyl-CoA + AMP + PP
How many ATP can be produced from Palmitoyl-CoA (16C)?
129 ATP
131 - 2 from beginning
What does Fat metabolism require?
Balance of carbohydrate:fat metabolism otherwise Ketone bodies formed.
