Lipid And Fatty Acid Metabolism* Flashcards
What are the 4 fates of lipids and fatty acids?
- Energy Substrates
- Precursors
- Structural Elements
- Signaling Molecules
What are 3 sources of lipids and fatty acids?
- Diet
- Adipose Storage
- Synthesis in Tissue
What are Apolipoproteins?
- Lipid Binding Proteins
- Combine with lids to form lipoproteins
- They have diverse functions
Examples of signaling molecules that fatty acids and lipids are precursors for?
- Serimide
- DAG
- Cholesterol
- leukotrienes
- thromboxanes
What two ways are Fatty Acids transported?
- Free fatty acids (carried by serum albumin)
2. Lipoproteins
What are Chylomicrons for And where are they synthesized?
- Dietary Triglyceride Transport
- Transport FAs for fuel or storage
- Synthesized in enterocyte ER
What are lipoproteins?
Phospholipid, cholesterol, and protein membrane-bound vesicles containing triglycerides
What are the 4 classes of lipoproteins?
- Chylomicrons –relatively large
- Very Low Density Lipoprotein (VLDL) –pretty big
- Low Density Lipoprotein (LDL)
- High Density Lipoprotein
Where do VLDL deliver fatty acids?
To target Tissues
What do apolipoproteins do?
Activate Lipases
What do LDL and HDL do?
Transport cholesterol
What do free fatty acids interact with?
Serum Albumin
What releases glucagon and when?
- Pancreas
- when we have low blood sugar
What does Protein Kinase A (PKA) do?
- Phosphorylates Perilipin
- This causes Perilipin to dissociate
Dissociation of Perilipin causes what?
Release of CGI (Comparative Gene Indicator)
What does CGI do?
Activates ATGL
Phosphorylated Perilipin also activates what?
HSL
What does MGL (Monoglyceride lipase) do?
Removes glycerol molecule to free up fatty acids.
What is Beta-oxidation?
Process of breaking down lipids to produce energy
What breaks down triglycerides?
Lipases
What are the two components of triglycerides and where can they go after dissociation?
- Glycerol: can go to glycolysis as Glyceraldehyde 3-phosphate
- Fatty acids: Form Acyl-CoA and then can help feed into citric acid cycle
What are the 3 stages of Fatty acid oxidation?
- Beta-Oxidation
- Citric Acid Cycle
- Oxidative Phosphorylation
What is produced during Beta-Oxidation?
- Acetyl CoA
2. NADH, FADH2
What is produced per oxidation step in Beta-oxidation?
1 Acetyl CoA
1 NADH + H+
1 FADH2