Choline

Question 1

3 important aspects of choline

Answer 1

1. not a B vit, dietary source of methyl groups
2. Makes SAM by alt pathway
3. related to betaine (BEETS!)

Question 2

how is dietary choline obtained

Answer 2

in food: phosphatidyl choline/lectin: soy, milk, egg yolk, peanuts

Question 3

AI choline and why

Answer 3

M: 550mg
W: 425mg

prevents liver damage from low methyl diet

Question 4

choline deficiency

Answer 4

increase ALT: alanine aminotransferase from liver damage

AI prevents this

Question 5

how do we obtain choline from de novo synthesis

Answer 5

from serine
add 3 methyls and remove carboxylic group

can’t be made from betaine, betaine/beets still maybe healthy bc acts directly to make SAM and ‘spares’ choline = decrease HCY

Question 6

choline betaine and folate pathway

Answer 6

choline in liver -> betaine

betaine donates methyl group to HCY

HCY -> methionine

methionine -> SAM -> HCY -> cysteine

or

HCY -> cobalamin/folate

Question 7

obtain phosphatidyl choline from phosphatidyl ethanolamine

Answer 7

add 3 methyl groups

PC = PE + 3 methyl using SAM as methyl donor

de novo and PE show that methyl groups could be limiting

eating choline provides body with methyl groups

Question 8

2 functions of choline

Answer 8

1. make PC and sphingomyelin (cell membranes)
2. acetylcholine (neuro)

Question 9

first sign of choline def liver damage

Answer 9

fatty liver

Question 10

UL choline

Answer 10

3.5g

danger of excess hypotension
early signs of excess: fishy body odor and nausea

UL for supplement and food sources