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40 Cards in this Set
- Front
- Back
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What are some sourced of Thiamin, and serving amount?
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Best source:
Ham: .91 mg / 4 oz Sweet potato (w/ Skin): 1.65 mg each |
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What method of preperation will destroy the vitamin and why?
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Heat and Water:
-Cooking thiamin in water will promote loss of thiamin because thiamin is destroyed in a alkaline environment. -Cooking thiamin with heat will also destroy the vitamin |
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What is the main form of thiamin found in animals?
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-Thiamin Diphosphate (TDP):
*The phosphorylated form of thiamin (phosphorylated at the OH side chain.) *Also known as TPP- Thiamin pyrophospahte *Represents 80% of tissue thiamin |
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What is the main form of Thiamin found in plants?
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Thiamin's free form is found in plants (not phosphorylated)
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What is TTP?
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Thiamin Triphosphate. A thiamin molecule with three phosphates where the OH used to be.
*Does not have a huge biological importance. |
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What does an intestinal phosphatase do?
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Responsible for the digestion of phosphorylated forms of thiamin.
-It removes (hydrolyzes) the phosphate group(s) from the thiamin prior to absorption. |
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What form of thiamin is absorbed?
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The free form
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What are two anti-thiamin factors?
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1. Thiaminase
2. Polyhydroxyphenols |
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Where does primary absorption of Thiamin occur?
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Jejunum and ileum.
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What are THTr1 and THTr2? and what effects these transporters?
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Thiamin transporters.
*ThTr1- Largely responsible for intestinal thiamin absorption. *Alcohol effects the intestinal expression of the transporters |
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What type of thiamin is most commonly found INSIDE cells?
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The phosphorylated form (although it is digested in the non-phosphorylated form).
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What must you have in order for phosphorylation to occur?
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Magnesium.
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What are the only forms of thiamin able to cross cell membranes to enter cells?
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TMP and free thiamin
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What percentage of TDP is present in the blood/cells?
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90%
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How does transport of thiamin into RED BLOOD CELLS occur?
How does thiamin transport into other tissues? |
Red blood cells- Facilitated diffusion
Other tissues- requires energy |
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When does passive diffusion of Thiamin occur?
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When you are taking a high amount of thiamin
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How is free thiamin absorbed?
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ThTr1 and Thtr2
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How is Thiamin monophosphate absorbed?
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Reduced Folate Carrier
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Where is 50% of thiamin found in the body?
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Skeletal muscles
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Hoe much Thiamin, approximately, does the human body contain? (tissue pool)
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30 mg
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What is a coenzyme?
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A small organic molecule required for the catalytic function of certain enzymes.
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What is the role of thiamin as a coenzyme?
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The removal of a carboxyl group [-COOH] from organic acids, resulting in the release of carbon and oxygen atoms as CO2.
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How is TDP used in energy transformation?
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TDP is a conenzyme for oxidative decarboxylation of pyruvate to Acetyl CoA
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What are two things which will impair absorption/ increase thiamin losses?
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Alcoholism- Impair absorption
Diuretic use- Increase losses, (congestive heart failure) |
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What is Polyhydroxyphenols, and give examples of where they're found.
*how is damage by this promoted and reduced |
An antithiamin factor which oxidizes the thiazole ring in thiamin.
Found in :Coffee, tea, blueberries, red cabbage. * Promoted by Mg and Ca * Reduced by Vit C |
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What is thiaminase, where is it found, and how can it be destroyed?
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An anti-thiamin factor. Its found in raw fish, and can be destroyed by cooking.
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What is the RDA for Men/Women?
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Men- 1.1 mg per day
Women- 1.2 mg per day |
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Why is there a high epidemic of thiamin deficiency in many countries?
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High intakes of polished rice, high alcohol intakes, and lack of fortified foods.
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How does a thiamin deficiency effect brain cells?
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Thiamin deficiency results in decreased cerebral energy metabolism, which results in accumulated lactate, resulting in brain cell death.
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What is a function of Thiamin?
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Branched chain amino acid metabolism-
Thiamine works as cofactor for Ketoacid dehydrogenase. |
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Where are BCAAs oxidized? And during which time?
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The skeletal muscle, during exercise.
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What is Beriberi?
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The result of a diet that is high in carbohydrates, and low in thiamin.
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What is Dry beriberi and it's symptoms? Is it life threatening?
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Thiamin Deficiency disease which has symptoms of:
1. Muscle weakness and wasting 2. Peripheral neuropathy (symmetrical & distal) 3. Not usually life threatening |
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What is wet beriberi, and its symptoms? is is fatal?
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Thiamin Deficiency disease which has symptoms of:
1. Cardiovascular system issues (rapid heart rate, etc) *It is more likely to be fatal then dry beriberi |
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What is Acute Beriberi and what are it's symptoms? Who does it occur most in? Is it fatal?
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Thiamin Deficiency disease which has symptoms of:
1. Anorexia 2. Vomiting 3. lactic aicdosis 4. Altered heart rate 5. Cardiomegaly *happens most in infants |
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What is the UL of thiamin?
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There is none
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How can thiamin be measured?
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By measuring thiamin in the blood or urine
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What is the Wenicke-Korskoff syndrome?
1. Who is it most common with? 2. what are the symptoms? 3. side effects of alcoholism on thiamin? |
A thiamin deficiency:
1. commonly observed in alcoholics. 2. Symptoms include: -Confusion -Loss of muscle coordination, leg tremor -Vision changes, abnormal eye movements -Double vision, eyelid drooping -Inability to form new memories -Loss of memory, can be severe -Making up stories (confabulation) -Hallucinations 3. Side effects of alcoholism: -Low thiamin intake -Impaired absorption -Impaired TPP (TDP) formation |
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What are some benefits of mega dosing thiamin?
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Protects against alzheimers, alcohol treatment, and MSUD (inborn error of metabolism)
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What is Roger's Syndrome?
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A rare genetic disorder characterized by megaloblastic anemia, hearing loss, and diabetes. - only 30 families have had it world wide.
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