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Flashcards in alpha-lipoid acid Deck (21)
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1

Alpha-Lipoid Acid

sulfur containing coenzyme found as oxidized form or reduced dihydrolipoic acid

2

reduced dihydrolipoic acid, AKA...

thioctic acid or R-5-(1,2-dithiolane) pentanoic acid

3

Naturally occurring lipoic acid?

D configuration (R-lipoic acid)

4

What can competitively inhibit and antagonize the uptake of D-lipoic acid (RLA)?

L-lipoid acid (SLA)

5

What is the bioavailability of D-lipoic acid (RLA)?

30 % at 200 mg

6

Lipoic acid can be synthesized by?

liver

7

What enzyme drives lipoic acid de novo synthesis?

lipoid acid synthase
- utilizes medium chain fatty acid octanoic acid and cysteine

8

Lipoic acid is a coenzyme for what?

oxidative decarboxylation of a-ketoacids by assisting acyl-group transfers

9

Lipoic acid is first converted to?

lipoamide

10

How is lipoic acid converted to lipoamide?

by its covalent bonding to a lysine residue (via amide linkage) belonging to dihydrolipoyl transacetylase

11

dihydrolipoyl transacetylase, also known as...

E2

12

E2 can be found in?

1. pyruvate dehydrogenase
2. a-ketogluterate dehydrogenase
3. branched chain a-ketoacid dehydrogenase

13

Why is arsenic poisonous?

covalently binds to lipoamide

14

What is a potent antioxidant in fat and water soluble mediums?

lipoic acid

15

Lipoic acid is known to scavenge?

hydroxyl radicals using dihydrolipoic acid form

16

What nutrient is can regenerate ascorbate and glutathione, and indirectly regerate vitamin E?

lipoic acid

17

Lipoic acid can increase intracellular levels of what?

coenzyme Q10 (CoQ10)

18

How does lipoic acid prevent atherosclerosis?

antioxidant protection of LDL's

19

What are the antihypertensive effects of Lipoic acid ?

decrease in oxidative stress to vascular endothelial cells

20

How does Lipoic acid effect diabetics?

improves neuropathic symptoms and deficits

21

safe dosage for Lipoic acid?

600 - 1800 mg