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30 Cards in this Set
- Front
- Back
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function of vitamins
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co enzymes (folate, B12)
H, e donor/acceptor hormones metabolism & hematopoesis |
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examples of water sol vitamins
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niacin, thiamin, riboflavin, pantothenic acid
biotin, pyridoxine (B6) and ascorbic acid folate, vitamin B12 |
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primary function of water sol vits
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co enzymes
utilize nuts if fed synthesize glucose if fasting |
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presentation of water sol vit deficiency
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rare
shows up in rapid grow tiss (RBC, intestines) |
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common characteristics of water sol vitamins
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convert to active
absorbed in SI (jejunum) (active & passive transport) not stored excess excreted in urine |
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active form of vit B 1
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thiamine
TPP |
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metabolic reactions requiring thiamine
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TPP (w/pantothen, riboflav, niacin, ATP)
pyruvate dehydrogenase (for ACoA) alpha KG dehydrogenase (for TCA & ) Transketolase (HMP) |
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thiamine deficiency
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effects glucose metabolism
(PD & transketolase most suscept) mod: confusion, ataxia -wernicke korsakoff severe: -beriberi (wet includes edema) |
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at risk for thiamine def
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elderly, etoh, pregnant, polished rice, glucose intravenous infusion
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vitamin B2
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riboflavin
FMN (PO3) FAD catalyze ox/red rxn metab of carbs & lipids |
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source of riboflavin
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milk & dairy
(meat,fish, green leafies) heat stable but degraded by light & alkali |
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cracks on side of mouth
shiney tongue (glossitis) dermatitis |
riboflavin deficiency
1.7 mg/day RDA |
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assessment of thiamine function
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transketolase (active in RBC)
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assessment of riboflavin status
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glutithione reductase
stimulation test- meas activity add cofactor 25% change indicate active |
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stimulation test
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test riboflavin
glutithione reductase |
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pellegra
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niacin deficiency (suspect EtOH)
3 D's diarrhea, dermatitis, dementia |
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niacin deficiency
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pellegra (suspect EtOH)
diarrhea, dermatitis, dementia |
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diarrhea, dementia, dermatitis
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pellegra, niacin deficiency
EtOH abuse susceptible "necklace lesion" &/or inflammation of mucus membranes indicate advanced disease |
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Niacin (essential or no?)
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can be derived from tryptophan
(uses thiamine, B6 & riboflavin) only vitamin w/amino acid precursor |
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problem with corn diet
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not enough niacin
(need alkali to release niacin from corn) |
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location of niacin in cells
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NAD+ in mito
for oxidative, catabolic rxns (generates NADH) NADPH in cyto reductive, anabolic pathways |
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peroxidine (what B vitamin)
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B6
pyridoxal-PLP (active) carry amino groups -transamination, energy from aa's (aspartate to OAA, ala to pyruvate, glutamine to alpha KG) substrate for TCA, rvsible -heme synthesis (produce ALA) -NT production (decarboxylatinos to NE, 5HT & His) -glycogen phosphorylase (stabilizes glyc breakdown to G 1 P) |
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depression, irritibility, nervousness, peripheral neuropathy
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pyridoxine deficit
RDA 1.5 -2 mg/day (100mg prot) occurs b/c intake lower than needed for protein intake |
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petechiae, corkscrew hairs, loose teeth, bad breath
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Vit C defic- Scurvey
RDA 60mg/day fruits, veg, potato not grain |
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location of vitamin C
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more in tissue than in serum
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function of vit C
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collagen(wound heal & maint CT)
-hydroxylate lysine for crosslinking bone -regen Fe2+ for proline hydroxylation NT's -keep Cu reduced for Epi/NE from dopamine |
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reaction of vit C
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form rad & rad scavenger
(dehydroascorbate recycled by GSH, diketogulonic acid excreted via urine) |
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cross linked collagen in urine
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indicates bone loss
(vit C) |
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function of biotin
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carry carboxyl (lipid synth)
Prop CoA to methylmalonyl CoA (branched chain aa catab) Pyr to OAA (pyr carboxylase- glneogen) ACoA to Mal CoA (ACoA carboxylase-FA synth) |
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neuro, rash, alopecia
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biotin deficiency
(Rare) bacteria in gut produce 1/2 of required b/c raw egg whites & Ab's |
