B vitamins

Question 1

T/F: does B1 work with B2, B3, and B5 in the pyruvate dehydrogenase reaction?

Answer 1

True

Question 2

T/F: B-vitamins may use phosphatases to help facilitate absorption?

Answer 2

True

Question 3

T/F: a thiamin deficiency can adversely affect nerve conduction through decreased production of acetylcholine?

Answer 3

True

Question 4

What vitamin coenzymes forms are based on a nucleotide structure?

Answer 4

NADPH, FADH2, FMN

Question 5

What vitamin coenzymes are needed in the Heme synthesis pathway?

Answer 5

B6, B7

Question 6

if a tryptophan load test was done on a patient who was deficient in B6, what would happen to the production of NAD+ and excretion of xanthurenic acid?

Answer 6

decreased production on NAD+

Increased excretion of xanthurenic acid.

Question 7

B6 is used to make all of the following NTs except:
a. GABA
b. Serotonin
c. Dopamine
D. acetylcholine

Answer 7

B6 does not make acetylcholine

Question 8

IF (intrinsic factor) : what is the role of B12?

Answer 8

IF is bound to B12 and internalized via receptor-mediated endocytosis

Question 9

All citric acid cycle dehydrogenases produce NADH except for?

Answer 9

succinate dehydrogenase which produces FADH2

Question 10

what are the physiologival effects of nicotinic acid from B3?

Answer 10

causes vasodilatory prostaglandin release, responsible for the niacin flush

causes enhanced fibrinolysis to help prevent clot buildup and improve blood flow

improves lipid profile: decrease VLDL/ DL and increase HDL

increased histamine release

Question 11

what enzyme blocks the production of vascodilatory prostaglandins in the niacin flush?

Answer 11

COX (cyclooxygenase).

so to prevent this use NSAIDs that inhibit COX for example aspirin.

Question 12

how can nicotinic acid be applied to Raynaud’s phenomenon?

Answer 12

vasodilatory mechanism

Question 13

why would nicotinic acid be harmful for someone with peptide ulcer disease?

Answer 13

NAC can cause increased histamine release, which mediates inflammation and vasodilations, increased histamine released makes symptoms worse because it stimulates gastric acid secretion irritating the ulcerated mucosa and increasing pain or bleeding

Question 14

why would nicotinic acid potentially lead to hyperglycemia?

Answer 14

decreased phosphorylation of glucose by glucokinase which regulates blood glucose by phosphorylation in the liver. With decreased activity there is less glucose uptake and storage in liver, leaving more in bloodstream.

Question 15

to avoid all of these side effects of nictonic acid, what is an alternative?

Answer 15

nicotinamide!

Question 16

one coenyzme form of B12 is Methylcobalamin that catalyzes the methionine synthase rxn to make methionine, what would a deficiency here cause?

Answer 16

Methyl folate trap

Question 17

what is a symptom that a b12 deficiency does NOT share with B9?

Answer 17

neurological deficit

Question 18

how is B12 uptake facilitated in enterocytes and also in tissues?

Answer 18

receptor mediated endocytosis

Question 19

what would you expect to see affected by a deficiency in B1 Thiamin?

Answer 19

CNS and/or cardiovascular system