Pyruvate Dehydrogenase

Question 1

Potential fates of pyruvate:

Answer 1

• Cori Cycle: Lactate - Liver - Glucose;
• Acetyl co A
• Gluconeogenesis
• Alanine Cycle: Alanine - Liver - Glucose

Question 2

What is pyruvate?

Answer 2

End product of glycolysis;

Question 3

How does pyruvate enters in the mitochondria?

Answer 3

Outer membrane: a voltage-gate porin complex
Inner: mitochondrialpyruvate carrier (MPC);

Question 4

Pyruvate is transported into mitochondria for:

Answer 4

Entry into TCA cycle
Gluconeogenesis

Question 5

Function of Pyruvate Carboxylase:

Answer 5

Activate Gluconeogenesis;

Question 6

Function of Pyruvate Dehydrogenase Complex:

Answer 6

Pyruvate is transformed into Acetyl coA - TCA Cycle

Question 7

If acety-Co A is HIGH, Pyruvate Carboxylase is…

Answer 7

stimulated

Increases Gluconeogenesis
Inhibits TCA Cycle;

Question 8

If ATP levels are HIGH, increases Gluconeogenesis.

Answer 8

TRUE

Question 9

Vit B1 is Thiamine, when gets activated, it name is…

Answer 9

Thiamine Pyrophosphate;

Question 10

Thiamine Deficiency causes less production of ATP.

Why?

Answer 10

Vitamin 1 (Thiamine) is converted to Thiamine Pyrophosphate that is a co-enzyme which is important in transform Pyruvate into acetyl-CO-A

Question 11

Deficiency of thiamine causes BERIBERI and Wernicke Korsakoff syndrome.

Answer 11

TRUE

Question 12

Beriberi - Dry type:

Answer 12

Polyneuritis, muscle Weakness;

Question 13

Beribery WET type:

Answer 13

tachycardia, high output heart failure, edema;

Question 14

Wernicke Korsakoff syndrome characteristics:

Answer 14

Alcoholics (malnourished, poor absorption vitamins)
Confusion confabulation

Question 15

If glucose is given first to an alcoholic without thiamine, the risk of worsening Wernicke-Korsakoff is higher.
Why?

Answer 15

Just because without Thiamine is not possible to convert Pyruvate into acetyl co A.

Question 16

FAD is synthesized from riboflavin B2.

Answer 16

Yes

Question 17

NAD+ is synthesized from niacin B3.

Answer 17

Used in electron transport.

Question 18

Tryptophan is used to synthesis NIACIN.

Answer 18

true

Question 19

Vitamin B5 - pantothenic acid (b5) is used to synthesize Coenzyme A

Answer 19

TRUE

Question 20

Cofactors for the pyruvate dehydrogenase complex:

Answer 20

B1-Thiamine
B2 - Ribolfavin FAD
B3 - Niacin (NAD)
B5 - Pantothenic Acid (CO A);

Question 21

The lipoic acid is inhibited by….

Remember Napoleon

Answer 21

ARSENIC;
Inhibits PDH - like thiamine deficiency;

Question 22

PDH (Pyruvate Dehydrogenase) Complex deficiency is a rare inborn error of metabolism. Often x Linked and most common cause of mutations in PDHA1 gene.

Answer 22

Most common IN MENS
Cannot effectively convert pyruvate into acetyl-coA.

Question 23

When acetyl- coA is low, gluconeogenesis is…

Answer 23

Inhibited

Question 24

In PDH complex deficiency, pyruvate is convevrted into Lactate and Alanine.

Answer 24

True

Question 25

Key findings of PDH deficiency:

Answer 25

Poor feeding;
Growth failure;
Developmental delays

Question 26

Labs findings in PDH deficiency:

Answer 26

Elevated alanine
Lactic acidosis

Question 27

Mitochondrial disorders: inborne error of metabolism all cause sever…

Answer 27

LACTIC ACIDOSIS

• PDH deficiency
• Pyruvate carboxilase deficiency;
• Cytochrome oxidase deficiencies;

Question 28

PDH complex deficiency:

Answer 28

Gives Thiamine, lipoic acid;
Ketogenic diet:
- Low carb, High fat, Ketogenic amino acids: lysine and leucine;
- Drives ketone production instead of glucose;