Lecture 6 Flashcards
Importance of transcription factors.
This is how genes become expressed.
Endogenous source of cholesterol.
De novo synthesis of Acetyl-CoA.
Statins.
They inhibit HMG-CoA reductase, thereby inhibiting cholesterol synthesis.
Bile acids.
Synthesized in the liver, secreted into the gallbladder, and then released into the intestine.
Bile acids.
Made from cholesterol in the liver, have a hydrophilic and hydrophobic phase, which allows for them to function as detergents. They are important signalling molecules: they can control the activity of transcription factors.
Degradation of lipids.
Occurs in the lumen of the intestine.
ACAT and MTP.
Enzymes that help assemble chylomicrons.
Lipoproteins are…
Covalent structures that allow interaction with many types of molecules.
Good and bad cholesterol.
The way cholesterol is being carried determines whether it is good or bad. Remember: lipoproteins carry cholesteryl esters. Note: the chemical moiety of both LDL and HDL are actually identical.
Bad cholesterol.
LDL.
Good cholesterol.
HDL.
Diet derived lipids.
Broken down in the stomach and then in the intestine; storage of triacylglycerol in the bloodstream and adipose tissue only occurs if there is an excess. Excess: chylomicrons repackage the lipoproteins into VLDL and the process repeats.
Apo A-1.
LCAT activator: responsible for turning cholesterol into cholesteryl esters.
Excess of cholesterol.
Turned into cholesteryl esters by LCAT; also ACAT.
Repackaged VLDL.
Same fate as dietary derived cholesterol.
