Ch.11 Fat Soluble Vitamins

Front 1

Fat Soluble Vitamins

Back 1

-Includes: Vitamin A, D, E, K
-Body treats each like a fat
*enters lymph before blood
*stored in liver and adipose

Front 2

Vitamin D

Back 2

-Calciferol
-Made in body from sunlight (cholesterol)
-Active form is D
-Activated by adding two hydroxyl groups (OH)
-Vitamin D acts more like a hormone
-OH groups added in liver and kidney
-Food sources:
*fortified milk, margarine, veal, beef, liver, fatty fish

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Vitamin D Function

Back 3

-Main role is in bone growth
-Maintain serum level of calcium and phosphorus by:
1. Increased uptake from GI
2. Increased reabsorption from kidney
3. Mobilize from bone
-Other functions include:
*Immune system
*Nervous system
*Pancreas
*Muscle
*Skin
*Reproductive system

Front 4

Vitamin D Deficiency

Back 4

-Often due to:
1. Dark skin
2. Lack of sunlight
3. Use of unfortified milk
-Infants and elderly often susceptible to deficiency
-Rickets-bone fails to calcify correctly causes abnormal bone growth including bowed legs
-Osteomalacia-adults form of rickets. Similar softening of bones.
-Osteoporosis-bone becomes brittle and fractures become more of a risk

Front 5

Vitamin D toxicity

Back 5

-Caused by use of concentrated supplements
-Symptoms unclude:
1. Increased serum Ca
2. Ca deposits and stones
3. Hardening of blood vessels

Front 6

Vitamin E

Back 6

-Tocopherol- "to bring forth offspring"
-Alpha- tocopherol has vitamin E activity in human body
-Toxicity:
*may effect blood clotting
*rare though
-Food Sources:
*PUFA plant oils, leafy green veg., liver, eggs, whole grains, nuts, seeds

Front 7

Vitamin E Functions

Back 7

-Fat tissue antioxidant
-Protects cell membranes
-Protects PUFA
-May protect LDL from oxidation and reduce risk of heart disease
-Restored by vitamin C

Front 8

Vitamin E Deficiency

Back 8

-Very rare
-Causes cell lysis
-Common sign is hemolytic anemia
-Premature born babies
-Neuromuscular dysfunction
-Rare issues that respond to vitamin E treatment:
1. Fibrocyctic breast disease
2. Intermittent claudication

Front 9

Vitamin A

Back 9

-Retinal
-Retinol
-Retinoic acid
-Beta-carotene (splits to form two retinol)
-Forms are interchangeable:
*retinal to retinol reversible
*change to retinoic acid is irreversible
-Retinol-binding protein (RBP)
*cells have special receptors for vitamin A
*each form has its own receptor

Front 10

Vitamin A Functions

Back 10

-Promoting vision
-Protein synthesis and cell differentiation
-Supports growth and reproduction
-Each form has specifically different functions in body
*makes conversions important

Front 11

Vitamin A and Vision

Back 11

-Maintains cornea
-Involved in light transduction to nerve impulse
-Rhodopsin are pigment molecules in eye
-Each are make of protein called opsin
-Opsin is bound to a cis-retinol

Front 12

Vision Transduction

Back 12

-Light bleaches opsin and changes cis-retinol to all trans-retinal
-Opsin releases retinal and disrupts neurons to form impulse
-Trans-retinal returns to cis and binds back to opsin
-Some retinal converted to retinoic acid

Front 13

Vitamin A Protein Synthesis/Cell Differentiation

Back 13

-Found in epithelial cells
1. Skin
2. Mucus membranes-various tissues
-Differentiation is when a cell is adapted for its specific function

Front 14

Vitamin A and Growth

Back 14

-Involved in bone reformation
-Sperm development in men
-Fetal development in women
-Child development
-Beta-carotene acts as an anti-oxidant if not converted to retinol

Front 15

Vitamin A Deficiency

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-Complication with infectious disease
1. Pneumonia
2. Measles
3. Malaria
-Night blindness-low retinal levels in retina leads to over bleaching of opsin
-Total blindness caused by degeneration of cornea
-Xerophthalmia-dry hardened cornea
-Keratomalacia-softening of cornea leads to irreversible blindness
-Keratinization-formation of keratin in epithelial cells

Front 16

Vitamin A Toxicity

Back 16

-Occurs when all available RBP are saturated
-Preformed vitamin A from animal products are a higher risk
-Beta-carotene will be stored under skin giving an orange hue to the skin
-Though not harmful supplemented beta-carotene may have adverse effect
-May cause weakening of the bone
-Birth defects are possible
*Teratogenic risk is seen when vitamin A is in excess around seventh week
-Vitamin A does not cure acne