Fatty Acid Oxidation

Question 1

What does hte carnitine shuttle do?

Answer 1

Attaches to long chain fatty acids to help them cross in to the inner mitochondrial membrane . Carnitine is then transfered back out of the inner mitochondrial membrane via carnitine acylcarnitine translocase to be recycled and used by another LCFA.

MCFA and SCFA do not need aassistance crossing in to mitochondria

Question 2

What does long chain fatty acid have to combine with to cross into the outer mitochondrial membrane?

Answer 2

CoA

MCFA and SCFA do not need aassistance crossing in to mitochondria

Question 3

HMG CoA in a ____________ state makes ketones known as acetoacetate and hydroxybuturate

Answer 3

catabolic

Question 4

What is Beta oxidation?

Answer 4

breaks down fatty acids, removing 2 carbons with each cycle

Question 5

What are the products of beta oxidation?

Answer 5

1 FADH
1 NADH
1 acetyl CoA +1 at end
(beta oxidation stops when fatty acid chanin becomes 2 carbon acetyl CoA)

Question 6

Which enzyme is affected in MCADD?

Answer 6

MCADD = Medium Chain Acyl CoA Dehydrogenase Deficiency
enyme: acyl CoA dehydrogenase
1st step of beta oxidation

Question 7

Symptoms:
- low tolderance for fasting
- aketotic/hypoketotic
- metabolic acidosis (+AG)
- hypoglycemia
- hyperammenemia
- dicarboxylic acidemia

Answer 7

MCADD

Question 8

What causes hypoglycemia in patients with MCADD?

Answer 8

• increased glucose utilization becuase there are no ketones to be used by the brain or muscle
• decreased gluconeogenesis

Question 9

Why does patients with MCADD benefit from carnitine supplementation?

Answer 9

• becuase medium chain acyl carnitine accumulates because it isn’t be ign broken down.
• this ties up carnitine, which is sued by other large molecules to enter the inner mitochondrial membrane
• leading to relative carnitine deficiency

Question 10

Why do patients with MCADD have hyperammenemia?

Answer 10

because when beta oxidation is not functioning there is less acetyl-CoA which leads to reduced synthesis of N-acetylglutamate which is essential for the urea cycle and since the urea cycle isn’t working as well there is build up of ammonia

I think this is how it works

Question 11

What are the 3 things to know about unsaturated fatty acid oxidation?

Answer 11

1. enoyl reducatse and enoyl isomerase are needed for unsaturated fats
2. net yield of ATP is lower than beta oxidation
3. naming unsaturated FA is #Cs:#double bonds (delta carbons with double bonds)