Vitamins

Question 1

Vitamin A

Answer 1

Use: antioxidant
Deficiency: night blindness, dry skin
Excess: arthralgia, fatigue, headache, skin changes, sore throat, alopecia, teratogenic

Question 2

Vitamin B1 (thiamine)

Answer 2

Use: decarboxylation reaction
- pyruvate dehydrogenase
- alpha ketoglutarate dehydrogenase
- transketolase
- branched chain amino acid dehydrogenase
Deficiency: ATP breakdown
- Wernicke-Korsakoff
- Wet Beriberi and Dry Beriberi

Question 3

Vitamin B2 (riboflavin)

Answer 3

Use: redox cofactor, FAD and FMN
Def: cheilosis, corneal vascularization

Question 4

Vitamin B3 (niacin)

Answer 4

Use: NAD and NADP, from tryptophan, requires B6 for synthesis
Def: glossitis, hartnup disease, malignant carcinoid syndrome, INH
- pellagra (diarrhea, dementia, dermatitis)
Excess: facial flushing

Question 5

Vitamin B5 (pantothenate)

Answer 5

Use: component of CoA and fatty acid synthase
Def: dermatitis enteritis alopecia adrenal insufficiency

Question 6

Vitamin B6 (pyridoxine)

Answer 6

Use: pyridoxal phosphate used in transamination (ALT and AST), decarboxylation reactions, glycogen phosphyrlase
- cystathoine, heme, niacin, histamine, neurotransmitters
Def: convulsions, hyperirritability, peripheral neuropathy, sideroblastic anemias from impaired hgb synthesis and iron excess

Question 7

Vitamin B7 (biotin)

Answer 7

Use: carboxylation enzymes cofactor
- pyruvate carboxylase
- acetyl coA carboxylase
- propionyl CoA carboxylase
Def: dermatitis, alopecia, enteritis

Question 8

Vitamin B9 (folic acid)

Answer 8

THF, transfer/methylation
- synthesis of DNA and RNA
Def: macrocytic, megaloblastic anemia (no neuro sx)
- most common vitamin deficiency in the US, seen in alcoholism and pregnancy

Question 9

Vitamin B12 (cobalamin)

Answer 9

Use: homocysteine methyltransferase
Def: macrocytic, megaloblastic anemia with neuro sx, hypersegmented PMNs

Question 10

Vitamin C

Answer 10

Antioxidant, iron absorption, hydroxylation of proline and lysine, dopamine to NE
Def: scurvy - swollen gums, bruising, hemarthrosis, anemia, poor wound healing, weakened immune response
Excess: N/V/D, fatigue, sleep problems

Question 11

Vitamin D

Answer 11

Use: increases Ca and phosphate, increase bone mineralization
Def: rickets in children, osteomalacia in adults
- hypocalcemic tetany
Excess: hypercalcemia, hypercalciuria, loss of appetite, stupor (sarcoidosis)

Question 12

Vitamin E

Answer 12

Use: antioxidant
Def: fragility of erythrocytes (hemolytic anemia), muscle weakness, posterior column and spinocerebellar tract demyelination

Question 13

Vitamin K

Answer 13

Use: catalyzes gamma-carboxylation of glutamic acid, concerned with blood clotting
Def: neonatal hemorrhage with increased PT and aPTT but normal bleeding time

Question 14

Zinc

Answer 14

Use: zinc fingers
Def: delayed wound healing, hypogonadism, decreased adult hair, dysgeusia, anosmia