Vitamin C

Question 1

Also known as ANTI-SCORBUTIC (scurvy) factor and ASCORBIC ACID

Answer 1

Vitamin C

Question 2

Humans and other primates CANNOT endogenously synthesize vitamin C d.t. ABSENCE of

Answer 2

GULONOLACTONE OXIDASE (in uronic acid pathway)

Question 3

Functions of Vitamin C

Answer 3

reducing agent

antioxidant

posttranslational modification, hydroxylation of lysine and proline in collagen synthesis

converts dopamine to NE (via dopamine B-hydroxylase)

iron absorption via conversion of ferric (Fe3+) ions to ferrous (Fe2+) ions

homogentisic acid synthesis

bile acid synthesis (via 7a-hydroxylase)

conversion of folate to its active form

adrenal steroid synthesis

Question 4

Vitamin C deficiency

Answer 4

SCURVY

petechiae, ecchymosis, coiled hairs, inflamed and bleeding gums

corkscrew hair

joint effusion, poor wound healing, fatigue

weakened immune response

Question 5

Occurs in infants b/w 6-12 mos when the diet is not supplemented w/ Vitamin C

Answer 5

Barlows Syndrome (Infantile Scurvy)

Question 6

Vitamin C Toxicity

Answer 6

nausea, vomiting, diarrhea

calcium oxalate (NEPHROLITHIASIS)

INCREASE risk for iron toxicity (d.t. increased dietary iron absorption)