Final Exam (CoQ10)

Question 1

*How many isoprene units attached to a benzene ring does CoQ10 have?

Answer 1

10biquinone

Question 2

50% of the bodys CoQ is found where?

Answer 2

Inner mitochondrial membrane

Question 3

Which form of CoQ is fully oxidized and has two double bonded oxygens?

Answer 3

Ubiquinone

Question 4

Which form of CoQ is fully reduced with two OH groups?

Answer 4

Ubiquinol

Question 5

What three enzymes are responsible for keeping CoQ reduced in cells/plasma?

Answer 5

1. NADH cytochrome reductase
2. NADH/NADPH oxidoreductase
3. NADPH CoQ reductase

Question 6

*In the mitochondria which two enzymes are there… along with what part of the electron transport chain are they a part of?

Answer 6

• NADH dehydrogenase (complex 1)

- succinate dehydrogenase (complex 2)

Question 7

Ubiquinone/Ubiquinol are better absorbed in what kind of form?

Answer 7

Oil based form

Question 8

*Is solubilized Ubiquinone/Ubiquinol better absorbed in the human?

Answer 8

Ubiquinol

Question 9

*As the ingested dose increases, what happens to the absorption rate?

Answer 9

LOWER % is absorbed

Question 10

High doses of what vitamin can interfere with CoQ absorption?

Answer 10

Vitamin E

Question 11

*Tissues synthesize CoQ from what two things?

Answer 11

• Farnesyl diphosphate (FPP

- Tyrosine

Question 12

*CoQ is synthesized intracelllularly using what as the fundamental building block?

Answer 12

• Mevalonate

Question 13

What are the 3 essential cofactors for CoQ biosynthesis?

Answer 13

• B6
• Iron
• Mg

Question 14

How many enzymatic steps are needed to make CoQ ?

Answer 14

17 enzymatic steps

Question 15

*In the mevalonate pathway, what is the rate limiting step? CoQ and cholesterol synthesis also use this enzyme…

Answer 15

HMG-CoA Reductase

Question 16

*Since CoQ and Cholesterol synthesis use HMG-CoA Reductase, what type of drug can actually inhibit both of these from working?

Answer 16

Statins

Question 17

When a patient is on statins, what nutrient must they be taking in conjunction with the statin?

Answer 17

CoQ10

Question 18

Free radicals which are not being scavenged by CoQ are allowed to destroy the mitochondrial membrane, leaking cytochrome C into the cell –> caspase cascade –> apoptosis… what is this disease called?

Answer 18

Rhabdomyolysis

Question 19

*Which organ is most susceptible to CoQ deficiency due to its high concentration within this organ?

Answer 19

• The heart
• Large number of mitochondria in cardiac muscle which makes sense that the concentration of CoQ is really high here
• CoQ also improves efficiency of energy production in cardiac muscle

Question 20

CoQ acts as an intermediate step in what pathway? It also provides what qualities intracellularly?

Answer 20

• Electron transport chain

- intracellular antioxidant

Question 21

What two substances can regenerate CoQ?

Answer 21

• DHLA (Dihydrolipoic Acid)

- Thioredoxin reductase

Question 22

Where is most of CoQ excreted?

Answer 22

Feces, although some can leave in the urine as well attached to glucuronide…

Question 23

Does CoQ reduce systolic, diastolic, or both?

Answer 23

BOTH

Question 24

When ubiquinol is used as an antioxidant, what is it converted into?

Answer 24

Ubisemiquinone