Fat-soluble vitamins are best absorbed in the presence of this nutrient.
Dietary fat
Storage form of vitamin A in adipose cells
Retinyl ester
A supplement containing one of these two forms of vitamin A will support all vitamin A functions in the body.
Retinol
Retinal
(also need niacin and riboflavin for conversion)
Protects lipid membranes from free radicals
RRR-alpha-tocopherol
A night blindness test is a functional assessment for which vitamin?
Vitamin A
(Dark adaptation threshold test is another)
This nutrient is needed to convert beta-carotene to retinal.
Iron
After absorption, vitamins A, E & K are primarily transported to the liver by which transporter?
Chylomicrons
Form of vitamin A that assists with gene expression.
Retinoic acid
(also cell differentiation)
Form of vitamin A that supports reproductive process is humans.
Retinol
Newborns
Phylloquinone is the form of _____ found in _____.
Vitamin K, Plants
High intakes of this vitamin promote the excretion of vitamin K.
Vitamin E
Vitamin E also:
1. Decreases absorption of K
2. Interferes with menaquinone metabolism (to MK-4)
Clotting factor that converts prothrombin to thrombin.
Factor X
Begins the extrinsic blood clotting cascade
Factor VII
This vitamin's UL is based on the increased risk for bleeding with very high intakes.
Vitamin E
Name two nutrients that decrease the bioavailability of dietary carotenoids.
2. Vitamin E (high intakes)
What TWO proteins does retinol bind to for transport out of the liver to systemic tissues?
1. Retinol binding protein
2. Transthyretin (Prealbumin)
Inadequate vitamin K promotes atherosclerosis through decreased carboxylation of this protein.
Matrix Gla Protein
This part of vitamin E's structure donates an electron to stabilize free radicals.
Phenolic function group
This form of vitamin A binds to opsin to form rhodopsin.
11-cis-retinal
Which tocopherol is gamma-tocopherol converted to in the liver?
NONE! Tocopherols cannot interconvert between each other.
Vitamin E deficiency can be caused by a defect in the expression of this protein.
Alpha-tocopherol transport protein
(Transfers RRR-alpha-tocopherol to be incorporated into VLDL)
Portion of the fatty acid chain that often receives an electron from Vitamin E.
Methylene group
What are the two 'fates' of the alpha-tocopherol radical?
1. Reacts with other peroxyl radicals to terminate free radical production
2. Recycled to alpha-tocopherol by vitamin C
How would a vitamin K deficiency affect bone health?