Fatty acids

Question 1

Chylomicrons

Answer 1

Store VLCFA and LCFA as TAGs from intestines, travel via lymphatic system

MCFA and SCFA bind to albumin

Question 2

Fatty Acid Synthesis (de novo)

Answer 2

Acetyl-CoA carboxylase
Need 14 NADPH (PPP) and ATP, B7

(+) insulin, citrate (substrate, source of acetyl coa)
(-) glucagon, palmitoyl coa (product)

Question 3

Fatty acid oxidation (beta oxidation)

Answer 3

Carnitine acyltransferase 1 (CPT1)

(-) malonyl coa

1. LCFA converted by CPT1 to fatty acyl carnitine, enters mitochondria via CAT
2. CPT2 converts back to fatty acyl coA
3. Beta oxidation

Carnitine is required to shuttle fatty acids >12 carbons
(-) malonyl CoA (indicates that we’re running FA synthesis instead)

Question 4

Citrate lyase

Answer 4

FA synthesis

Citrate to acetyl coa

Question 5

Acetyl coa carboxyalse

Answer 5

FA synthesis

Acetyl CoA to malonyl Coa

(+) insulin dephosphorylates
(-) glucagon and AMP activate AMPK to phosphorylate ACC

Question 6

TAG synthesis

Answer 6

Liver: Glucose borken into glycerol by glycerol kinase (store in VLDLS)
Adipose: glucose made into Glycerol-3-phosphate

Regulated by hormone sensitive lipase:
Glucagon = HSL = TAG breakdown: FA to tissues, glycerol to liver

Question 7

CPT deficiency

Answer 7

CPT1: liver, fasting hypoglycemia
CPTII: muscle and heart, cardiomyopathy

Question 8

Carnitine deficiency

Answer 8

Synthesized from lysine and methionine, but can have CAT deficiency so reduced carnitine in plasma, cant do long chain beta oxidation

Question 9

Gluconeogenesis and Beta oxidation

Answer 9

Glycerol from TAG can be used for gluconeogenesis, which can use the ATP from beta oxidation

Cannot use acetyl coa from beta ox in gluco… its an activator not a substrate

Question 10

MCADD

Answer 10

Inborn (AR) disorder of beta ox

Fasting hypoglycemia, build up of medium chain in urine