Folate Reading

Question 1

2 Most common and severe NTD’s

Answer 1

anencephaly - usually results in stillbirth or die after birth
spina bifida - severe lifelong disabilities

Question 2

What is neurulation?

Answer 2

refers to the folding process in vertebrate embryos, which includes the transformation of the neural plate into the neural tube.
Starts with the formation of the neural plate from ectodermal cells and culminating in the closure of the neural tube.

Question 3

When is neural tube closure completed?

Answer 3

28 days post conception (about the time the woman realizes she is pregnant).

Question 4

How do auto-antibodies effect folate intake?

Answer 4

They bind to the folate receptors and inhibit folate uptake (increase NTD’s).

Question 5

What is the bioactive form of folate?

Answer 5

THF - tetrahydrofolate

Question 6

What is the main form of folate in blood circulation?

Answer 6

5-MeTHF. Taken up into the cells by carriers or receptors.

Question 7

What is the gene involved in methylation?

Answer 7

MTHFR

Question 8

What is the bodies main methyl donor and why is it important?

Answer 8

SAM (S-adenosylmethionine)

has roles in DNA (gene regulation), protein development, and lipid synthesis.

Question 9

What is the most important function of methylation?

Answer 9

The synthesis of neucleotides

Question 10

What happens if there is inadequate 5-MeTHF or B12?

Answer 10

Homocysteine accumulates in the cell which can then lead to a build up of SAM which can lead to a dysregulation of gene expression, protein fxn, and lipid and neurotransmitter metabolism due to methylation inhibition.

Question 11

How does the MTHFR CC, CT, and CT genotype affect the folate metabolism?

Answer 11

CC Produces the variant with the highest enzymatic activity which results in lower 5, 10-methylene THF and 10-formyl THF available for DNA synthesis.
Higher 5-methyl THF available for adequate methylation. Decreased DNA synthesis and increased methylation.

CT has an intermediate effect

TT has the lowest MTHFR enzymatic activity which leads to increased 5, 10-methylene THF and 10-formyl THF for DNA synthesis and decreased 5-methyl THF which decreased methylation and increases NTD risk. Increased DNA synthesis and decreased methyation.

Question 12

What other B vitamins other than folate affect folate metabolism?

Answer 12

B12, B6, and B2.

B12 is involved in conversion of 5-MeTHF into methionine > SAM > homocysteine