MODULE 1 Week 2: Vitamin E Flashcards
** Does vitamin E have antioxidant function?
Yes
** Are polyunsaturated fats susceptible to oxidation?
Yes
** Vitamin E and CNS (vitamin helps prevent??)
Vitamin E important for brain/CNS health because it acts as a antioxidant and prevents excessive (lipid) oxidation
Tocopherols v Tocotrienols (what is structural difference?)
Tocopherol = have SATURATED side chains (16 carbons)
Tocotrienols = have UNSATURATED side chains (16 carbons)
** Cerebellum & vitamin E (deficiency)
Vitamin E def associated with cerebellar ataxia, which presents as BALANCE ISSUES/COORDINATION
** Vitamin E Deficiency presents as:
- Balance/coordination issues
- Reduced MYELINATION (decreased neuromuscular coordination)
- Reduced fertility
- Memory loss/declined cognitive function (because exposes neurons to free-radial damage)
** Vitamin E and Alzheimer’s
Effective in reducing neurocognitive decline (because protects neurons from free-radical damage/oxidation)
** Celiac and chrons and lipid-soluble vitamin absorption
Chronic digestive impairment via these conditions reduces the capacity for absorption of these vitamins
** Food rich in Vitamin E
- nuts
- seeds
- whole grains
- vegetable oils (corn/soybean)
- leafy green vegetables
** Predominant form of Vitamin E found in the blood and tissues
Alpha tocopherol
** Where is Vitamin E stored in the body (mostly)?
Adipose tissue
** Tocotrienol v tocopherol & digestion
Tocopherol from food does NOT require any digestion prior to absorption
Tocotrienol DOES require digestion (bile salts)
** Preference for alpha-tocopherol because?
Because of the specific transfer PROTEIN it is bound to
** Alpha or beta tocopherol in VLDL (recirculated by the liver)
Alpha
** Principal function of Vitamin E
Lipid-soluble antioxidant! (Prevents lipid peroxidation)
** Lipid peroxidation
Oxidative degeneration of lipids (free radicals “steal” electrons from the lipids in cell membranes, resulting in cell/membrane damage)
** How does vitamin protect membranes/membrane integrity?
Vit E acts as an ANTIOXIDANT by preventing free-radical oxidative activity that causes damage to the membrane
** Free radical/antioxidant, machine gun/bullet proof vest
Free radicals (like a machine gun shooting and damaging cells/tissues etc.)
Antioxidants (like a bullet proof vest preventing that damage)
** Vitamin C and glutathione
Taking vitamin C helps to recycle glutathione (master antioxidant)
** Most effective form of Vitamin E (as an antioxidant); what about structure allows for this?
Alpha tocopherol; OH group attached to phenol ring with stabilizing electrons basis for antioxidant activity
** Vitamin E prevents lipid peroxidation by?
Termination free radicals, “quenching” reactive O2
** Non-antioxidant functions of Vitamin E
- cell signaling
- Gene expression
- Neuroprotective, anti carcinogenic, reduce cholesterol (TOCOTRIENOLS)
** Recent study on Vitamin E + fish oil and menstrual pain (findings)
Found synergistic effect of Vitamin E and fish oils (EPA/DHA) on reducing dysmenorrhea (significantly)
** Supplements to help with estrogen dominance
- Progesterone
- DIM
- Calcium D-glucarate
** Vitamin E and reproductive functions
Deficiency of vit E interferes with proper fertility/productive function
** 2 main components of brain/neurons (fat type substances)
- cholesterol
- polyunsaturated fats
** Ataxia
Abnormal and uncoordinated physical movements
Bariatric surgery and nutrient absorption
Altering anatomy with this surgery tends to results in vitamin and mineral deficiencies (because remove organs/mechanisms body needs for proper absorption)
** Vitamin E encompasses X compounds (vitamers)?
8
Synthetic forms of alpha-tocopherol designated with what 2 letters?
DL
Vitamin E is primarily absorbed where?
Jejunum
** Absorption range of vitamin E
20-70%
** Why is there a tolerable upper limit to vitamin A (hint absorption)
Higher intake associated with REDUCED ABSORPTION
** How does vitamin E play a role in glucose/metabolic control? (Related to diabetes)
Vitamin E ENHANCES cellular glucose uptake, which is important for diabetes
** Vitamin E RDA, smoking, intense exercise connection
Both smoking and intense exercise created a lot fo OXIDATIVE STRESS so vit E could protect against that (due to antioxidant abilities)
- QUENCHES lipid peroxidation
RDA MIGHT BE HIGHER FOR THESE PEOPLE
** Which tocopherol provides the most vitamin E activity in the US food supply?
GAMmA
** What portions of plants provide tocopherols other an alpha?
everything EXCEPT the leaves
- Will people following a low-fat diet be high or low in vitamin E?
LOW
** A deficiency of alphaTTP (what is?) by what? Leads to vitamin E deficiency (genetic deficiency associated with vit E/what tocopherol?)
Genetic deficiency of ALPHA TOCOPHEROL/ a-tocopherol TRANSFER PROTEIN leads to vit E deficiency
** Which lipoproteins carry most of vitamin E in the blood?
LDLs and HDLs
- T/F vitamin E is primarily incorporated in the plasma, mitochondrial, and microsomal membranes?
T
** Other than adipose, where is Vit E also stored?
Liver
Plasma
Brain
Skeletal muscle etc.
** The mechanism by which vitamin E protects the membrane from destruction is….? (Hint peroxidation)
Prevents peroxidation of unsaturated acids in the phospholipids of the membranes
** Why are erythrocytes (RBC) membranes particularly vulnerable to oxidation? (Hint O2, fatty acids)
- they are high in fatty acids (easily oxidized)
- often come in contact with oxygen
** Is singlet oxygen a reactive or non-reactive compound?
HIGHLY reactive
** “quenching” + Vit E
Process by which electronically excited molecules (LIKE SINGLET OXYGEN) are inactived (by vitamin E)
- Most effective tocopherol in “quenching”
Alpha
*** Vitamin E & heart disease (hint LDLs)
Vitamin can PREVENT oxidation of LDLS
Oxidized LDLs are what cause FOAM cells to form
Foam cells can break off an cause CLOTS
** Alpha tocopherol and atherosclerosis (hint platelets & inflammation)
Vitamin E can prevent PLATELET AGGREGATION & ADHESION that contributes to atherosclerosis
AND prevents inflammatory response that causes arterial tissue damage
** Vitamin E and prostate cancer
Vitamin E thought to INCREASE RISK of prostate cancer
** Alpha-tocopherol and cholesterol
Vit E/alpha-tocopherol involved in CHOLESTEROL SYNTHESIS
** Tocotrienols and cholesterol
Exhibit cholesterol lowering abilities
** Vitamin E and selenium
Vitamin E function dependent on SELENIUM DEPENDENT glutathione
** Is there a tolerable upper limit to vitamin E and why?
- Yes because high levels can inhibit absorption
2. High levels can IMPAIR BLEEDING/COAGULATION
** Vitamin E and vitamin K (conversion??)
Vitamin E impairs Vit K absorption
Inhibits conversion of phylloquinone to menaquinone
** Vitamin E and beta carotene
Vitamin E INHIBITS beta carotene absorption in the intestines
** Symptoms of vitamin E deficiency
- Hemolytic anemia (because RBCs become fragile because membrane is impacted)
- Ataxia
- Peripheral neuropathy
- Weakness
**Gamma tocopherol and US diet
** Gamma tocopherol is MAIN form of vitamin E in US/Standard American diet
