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Flashcards in Nutrition Deficiencies Deck (83)
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1

Function of Vit A
- Liver, leafy vegetables

- Antioxidant
- Visual pigment
- Normal differentiation of epi cells into specialized tissue (pancreatic cells, mucus-secreting cells)
- Prevents squamous metaplasia

2

What is Vit A used to treat?

- Measles
- AML subtype M3 (all-trans retinoic acid)
- Severe cystic acne

3

Vit A Deficiency

- NIGHT BLINDNESS (nyctalopia)
- Dry, scaly skin (xerosis cutis)
- Corneal degeneration (keratomalacia)
- Bitot spots on conjunctiva
- Immunosuppression

4

Acute Vit A Toxicity

- N/v, vertigo, blurred vision

5

Chronic Vit A Toxicity

- Alopecia, dry skin, hepatic toxicity, arthralgias, pseudotumor cerebri (papilledema)

6

Vitamin B1

Thiamine

7

Enzymes thiamine pyrophosphate (B1) is cofactor for:

- Pyruvate dehydrogenase (glycolysis --> TCA)
- alpha-KG dehydrogenase (TCA)
- Transketolase (HMP shunt)
- Branched chain ketoacid dehydrogenase

8

Vit B1 Deficiency

- Impaired glucose breakdown --> ATP depletion worsened by glucose infusion (give thiamine before IV glucose)
- Highly aerobic tissues (brain, heart) are affected first
- Wenicke-Korsakoff
- Beriberi

9

Who becomes Vit B1 deficient?

Malnutrition, alcoholism, countries where "polished rice" is staple

10

Dx of Vit B1 deficiency?

Increase in RBC transketolase activity following Vit B1 administration

11

Pyruvate dehydrogenase cofactors?

TPP, lipoic acid, CoA, FADH2, NADH

12

Wenicke-Korsakoff Syndrome

B1 def
- Confusion, ophthalmoplegia, ataxia
- Confabulation, personality change, permanent memory loss
- Damage to medial dorsal nucleus of thalamus, mammillary bodies

13

Dry Beriberi

B1 def
Polyneuritis, symmetrical muscle wasting

14

Wet Beriberi

B1 def
High-output cardiac failure (dilated cardiomyopathy), edema

15

Vitamin B2

Riboflavin

16

Vit B2 Function

Component of FAD and FMN
- Cofactors in redox rxns (ex. succinate dehydrogenase rxn in TCA cycle)

17

Vit B2 Deficiency

- Cheilosis (inflammation of lips, scaling and fissures at the corner of the moth)
- Corneal vascularization
- Magenta tongue

18

When can B2 supplementation be helpful?

Infants undergoing UV light therapy for neonatal jaundice

19

Vitamin B3

Niacin

20

Vit B3 Function

- Constituent of NAD+, NADP+ (redox rxns)

21

What is niacin derived from?

Tryptophan

22

What does niacin synthesis require?

B2 (riboflavin) and B6 (pyridoxine)

23

What is niacin used to treat?

Dyslipidemia - lower levels of VLDL and raises levels of HDL

24

Vit B3 Deficiency

- Glossitis
- Pellagra

25

Symptoms of pellagra?

- Diarrhea, dementia, dermatitis (C3/C4 dermatome circumfrential "broad collar" rash, hyperpigmentation of sun exposed skin)

26

Causes of pellagra?

- Hartnup disease
- Malignant carcinoid syndrome (increased tryptophan metabolism)
- Isoniazid (decreased Vit B6)

27

Hartnup Disease

- AR
- Deficiency of neutral AA (ex. tryptophan) transporters in proximal renal tubule and on enterocytes --> neutral aminoaciduria and decreased absorption from gut --> decreased tryptophan conversion to niacin --> pellagra-like sx
- Rx: high-protein diet and nicotinic acid

28

Vit B3 Excess

- Facial flushing (induced by PG, not HA) - can avoid by taking aspirin with niacin
- Hyperglycemia, hyperuricemia (gout)

29

Vit B5

Pantothenic acid

30

Vit B5 Function

- CoA (cofactor for acyl transfer)
- Fatty acid synthase