Vitamin Flashcards Preview

MCP > Vitamin > Flashcards

Flashcards in Vitamin Deck (38):
1

What are the lipid soluble vitamins? Is toxicity or deficiency more of the problem?

A, D, E, K; toxicity more of a problem since they are more easily stored

2

What are the water soluble vitamins? Is toxicity or deficiency more of the problem?

B, C; deficiency since they are more easily excreted in urine

3

What functions is Vitamin A involved in?

Visual cycle with rhodopsin and cone opsins; synthesizing glycoproteins and mucosaccs; retinoic acid as a hormone; antioxidant

4

What are Vitamin A deficiencies?

Night blindness, xerophthalmia later; follicular hyperkeratosis (like goosebumps); anemia; poor growth in kids; increased vulternability to infection and cancer

5

Who is susceptible to Vit A deficiencies?

Poor, malnourished, premature babies

6

What is the order of retinoic acid formation from beta carotene?

Beta carotene --> all-trans retinol --> all trans retinal --> retinoic acid (hormone) -->gene transcription

7

What are the functions of Vit D?

Maintaining bone and calcium homeostasis; could have wide range of activity, but definitely acts as hormone

8

What are Vit D deficiencies?

Rickets in kids; osteomalacia in adults; increased vulnerability to cancers like breast, metabolic syndromes, infections

9

Who's susceptible to Vit D?

Poor, elderly, alcholics; other groups with mild deficiencies

10

Although toxicity is rare, what does excess Vit D lead to?

High serum levels of calcium and bone loss

11

What is thought to contribute to correlation between Vit D levels and cancer risk?

The vitamin D receptor

12

What is the function of Vit K? What does it catalyze?

Localizing of the enzymes required for clotting; it catalyzes addition of gamma-carboxyglutamate to clotting enzymes

13

What are Vit K deficiency consequences?

Easy bruising, bleeding, hemorrhage

14

Who is susceptible to Vit K def?

Newborn infants (lacking klebsiella); long-term antibiotics and patients; elderly or those with defects in fat absorption

15

What structure does Vit K have?

Quinone ring

16

How does warfarin act as an anticoagulant?

It inhibits Vit K's activities

17

What does Vit E do?

Serves as an ANTIOXIDANT to scavenge free rads; protect membranes from damage and prevent oxidation of LDL (foam cells potentially)

18

If you had a Vit E deficiency what would you see?

Cardiovascular disease, neurological symptoms (Vit E can be in the myelin sheath)

19

Who is susceptible to Vit E deficiency?

Patients with severe prolonged defects in absorption (e.g. celiac disease) or genetic defects

20

What is Vit C responsible for?

Cofactor for oxidases involved in collagen formation; needed for steroid synthesis in stress response; aids in iron absorption; antioxidant

21

What do you see with Vit C deficiencies (mild and severe)?

Bruising, immunocompromised; severe is scurvy (decreased wound healing, osteoporosis, hemorrhage, anemia, fatigue, corkscrew hairs, pinpoint hemorrhages);

22

Who is susceptible to Vit C deficiencies?

People with poor diet, smokers

23

What specific reactions is Vit C involved in?

Prolyl and lysyl hydroxylases for collagen biosynthesis; also epi synthesis

24

What are the B-complex vitamins?

Thiamine (B1), Riboflavin (B2), Niacin (B3), Biotin, Pantothenic acid (B5), Pyridoxine (B6); Folate (B9) and Cobalamin (B12)

25

What are common effects of deficiency of energy-releaseing B vits?

Dermatitis, glossitis, diarrhea; nervous system affected, peripheral neuropathy, depression/confusion, lack of coordination, malaise

26

What is the function of B1?

Required cofactor for several enzymes; critical in nervous system

27

Deficiencies of B1?

Mild: GI; depression, fatigue (poor, elderly); Moderate: Wernicke-Korsakoff syndrome (alcoholics); Severe: Beriberi (people dependent on polished rice, perhaps alcoholics)

28

What do you see in Wernicke-Korsakoff?

Mental disturbance, unsteady gait, uncoordinated eye movements; perhaps CHF

29

What is beriberi characterized by? What is the difference between dry and wet?

Extreme muscle weakness, poly-neuropathy, heart failure; in wet beriberi, we see edema

30

What is riboflavin a precursor to?

FAD and FMN

31

What does a B2 deficiency lead to?

Ariboflavinosis: rash around nose, inflammation of mouth and tongue, burning and itchy eyes, light sensitivity (uncommon)

32

Susceptible groups for B2 deficiency?

Alcoholics (deficiency uncommon)

33

What is niacin a precursor to? Who could you give it to?

NAD and NADP; hypercholesterolemia or hypertriglyceridemia patients

34

What can cause biotin deficiency?

Eating a lot of raw eggs

35

What is pantothenic acid (vit B5) required for?

CoA synthesis

36

What is pyridoxine a precursor to? What else is it required for?

PLP; required for glycogen breakdown and GABA and heme synthesis

37

What are deficiencies characterized by (mild and severe)

Mild: irritability, nervousness, depression; Severe: pripheral neuropathy, convulsions, decreased glucose tolerance, hyperhomocysteinemia, anemia

38

Who's susceptible to deficiency?

Patients treated with certain drugs, like the TB drug isoniazid