Term
| What are the major fat and water-soluble vitamins? |
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Definition
1) Fat
- ADEK
2) Water (energy)
- Thiamine (B1)
- Riboflavin (B2)
- Niacin (B3)
- Panthothenic acid (B5)
- Pyridoxine (B6)
- Biotin
3) Water (Hematopoietic)
- Folic acid
- B12 |
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Term
What type of deficiency might a person with night blindness, impaired immune function and follicular keratosis have?
What is the functional importance of this nutrient and what should your patient eat to replenish stores? |
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Definition
Vitamin A (retinol) deficiency
1) Critical electron shuttling component in vision and ligand for RXR that is important for nuclear lipid receptor function and cell growth/differentiation in development.
2) Eggs, meats, carrots, cantalope |
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Term
| Why should pregnant women with psoriasis be careful when treating acne with commonly available products? |
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Definition
| Vitamin A exces can cause birth defects and abortion |
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Term
What type of deficiency might a person with rickets and bone mineralization issues have?
What is the normal function of this chemical and how can it be found in the diet? |
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Definition
Vitamin D (also synthesized from cholesterol with UV exposure)
1) Ligand for nuclear lipid receptor that regulates gene express (works with PTH to regulate calcium absorption from gut and reabsorption from kidney)
**regulates insulin secretion, immune function and BP**
2) Found in meat, fish, eggs, milk |
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Term
| Patient presents complaining of very common bruising. What vitamin deficiency might be responsible and why? |
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Definition
Vitamin K (fat soluble)
1) Co-factor for carboxylase that adds Co2 to glutamic acid, resulting in conversion to gamma-carboxyglutamic acid (Gla)
**this action is specific to small number of proteins that use carboxy-glutamate in calcium binding, like THROMBIN |
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Term
| What are the major functions and dietary sources of Thiamine (B1)? |
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Definition
1) Critical co-factor for enzymes involved in energetics and "information management" (genomic)
- Dehydrogenases in TCA cycle/mitochondria
- Transketolase in pentose-shunt enzyme (formation of ribose 1 phosphate)
2) Grains, legumes, nuts, leafy vegetables |
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Term
Patient presents with recent weight loss, emotional disturbances and impaired sensory perception. You ask them about their diet and find it is lacking in legumes, leafy vegetables and grains/nuts.
What could be going on? |
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Definition
| Sounds like Beri Beri from Thiamine deficiency (B1) |
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Term
| What is the function of the vitamin that is lacking in patients that present with sore throat (redness and swelling of the mouth and throat mucosa), cheilosis and angular stomatitis (cracking of the lips and corners of the mouth), and glossitis (magenta tongue with atrophy)? |
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Definition
This description fits Ariboflavinosis, which results from Riboflavin (B2) deficiency.
**Not dissimilar from Pallegra/niacin**
- Riboflavin is only dietarily available (leafy plants, grains, milks, eggs) and functions as cofactor for enzymes in electron transfer reactions. |
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Term
A patient presents with dermatitisand hyperkeratosis. During the h/w, it becomes apparent that they are also experiencing demented beliefs.
What is the functional important of the vitamin that, when missing, could cause these symptoms? |
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Definition
Pallegra- Niacin (B3), a problem when diet depends too heavily on CHO sources such as corn (why mexicans use lime!)
- component of e-transferring cofactors NAD, NADP
**Excess supplementation can cause flushing, hepatotoxicity** |
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Term
What vitamin is associated with each of the following functions. What is the associated deficiency?
1) e-tranferring cofactors NAD, NADP
2) cofactor for acetylation and acyl transfer reactions in post-translational modification and FA metabolism
3) Co-factor for enzymes that carboxylate biomolecules found in cooked eggs
4) Co-factor for enzymes important for energetics like Dehydrogenases and Transketolase
5) Co-factor for glutamic acid carboxylase |
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Definition
All water soluble
1) Niacin- Pallegra- dermatitis, dementia, hyperkeratosis
2) Pantothenic acid (B5)- malnourished POW with burning and numbness in feet
3) Biotin- extended raw egg consumption with avidin-biotin binding and poor absorption (facial fat distribution and characteristic rash)
4) Thiamin (B1)- Beri Beri (weight loss, emotional disturbances and impaired sensory perception)
5) Vitamin K- easy bruising, abnormal coagulation |
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Term
| What might happen if a patient "over-supplemented" Pyridoxine (B6)? |
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Definition
Sensory neuropathy (>1 gm/day)
enzyme important for transamination, deamination and decarboxylation |
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Term
Patient presents with recent hair loss and red rash around eyes, nose, mouth and genitalia. They are feeling depressed and generally lethargic and are experiencing tingling sensations in their extremities.
Their face appears to have a strange distribution of fatty tissue.
What is going on? |
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Definition
| Biotin deficiency (rash with face fat is characteristic) with dematological and neurological symptoms |
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Term
| What are the good sources of Folic acid and why did the FDA mandate addition of 1.4 mg/kg to reined grain products? |
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Definition
Found in spinach, asparagus, lentils and beans and enriched to prevent neural tube defects.
Remember, Folic acid mediated one-carbon transfer reactions that are important in purine, pyrimidine and methionine/homocysteine metabolism
**Dihydrofolate reductase inhibited by methotrexate). |
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Term
| What 2 enzymatic reactions require Vitamin B12 (cobalamin)? |
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Definition
Get it in shellfish, fish, meats, eggs, milk
1) Methionine synthase (homocysteine to met)
- Met is important for SAM synthesis and downstream DNA/RNA methylation
2) L-methylamonyl-CoA mutase (succinyl CoA formation- heme biosynthesis) |
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Term
True or False:
The FDA does not recommend B vitamin supplements to reduce risk of heart disease and stroke |
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Definition
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Term
| Why might patients receiving long-term treatment for GERD develop pernicious anemia? |
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Definition
If they are on a PPI, 2-3 year use can induce B12 deficiency by changing the pH of the gastric compartment and preventing absorption.
H2-blockers DO NOT have this problem. |
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Term
| What nutrient deficiency causes bleeding and bruising, hair and tooth loss, joint pain and swelling and weakening of blood vessels, connective tissue and bone? |
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Definition
Scurvy (Vitamin C)
Humans cannot synthesize the antioxidant/co-factor, which is important for collagen, NE and carnitine biosynthesis.
Eat some citrus! Tomatoes, peppers, broccoli and potatoes also have it. |
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Term
| Is antioxidant vitamin supplementation a useful strategy to limit CVD? |
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Definition
Theory was antioxidant vitamins inhibit oxidation or uptake of LDL, preventing atherogenesis.
DID NOT HOLD UP in clinical studies. Vitamin E supplementation (Tocopherol) did not work. |
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Term
| What is the function of Vitamin E? |
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Definition
Tocopherol (synthesized by gut bacteria as well) is a free-radical scavenger found in oil, plant leaves, nuts and avocados.
Studies did NOT show benefit in preventing CVD. |
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Term
True or False:
fat-soluble vitamins are more likely to be associated with dietary deficiencies than with excess toxicity. |
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Definition
False!
ADEK are co-absorbed with dietary fat and can accumulate, exerting toxic effects
Water soluble vitamins have greater rate of turnover, and a greater likelihood for deficiency. |
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