Biochem - Fat Soluble Vitamins Flashcards
What are the differences between fat and water soluble vitamins?
Fat soluble vitamins:
- Require bile for digestion and absorption
- travel through lymphatic system
- many require transport proteins in bloodstream
- excess is stored in liver and adipose tissue
- not readily excreted (so risk of toxicity is greater)
What is the precursor for Vitamin A?
Beta carotene
Vitamin A’s role in cell differentiation, reproduction, and growth :
Epithelial cells Goblet cells Sperm development Normal fetal development Growth of children - bone remodeling Antioxidant
3 forms of vitamin A in the body
Retinal - vision
Retinol - reproduction
Retinoic acid - growth
Vitamin A deficiency
Measles
Night blindness
Blindness
Keratinization
Vitamin A toxicity
Bone defects
Birth defects
*no effect on acne
Vitamin D forms
Calciferol
D2 from plants (ergocalciferol)
D3 from animals (cholecalciferol)
Not an essential nutrient
Roles of Vitamin D
Bone growth
Protects against cognitive decline
Can enhance or suppress gene activity
Vitamin D deficiency
Production of calbindin, a protein that binds calcium in intestinal cells
-so this can create Ca deficiency
Rickets (children, bones bend)
Osteomalacia (adults, soft, brittle, flexible, deformed bones)
Osteoporosis
Vitamin D toxicity
Raises blood [Ca]
Forms stones in soft tissues
May harden blood vessels
Can cause death
Sources of vitamin D
Sunlight
Oily fish
Egg yolks
Fortified milk
Subgroups of Vitamin E?
Compounds of each?
Which are maintained in the body?
Tocopherols
Tocoyrienols
Each contains 4 compounds: Alpha Beta Gamma Delta
*only alpha tocopherol maintained in the body
Vitamin E is useful because__
Antioxidant properties
- protects cells
- heart disease and protection of LDLs
Vitamin E deficiency
Fat malabsorption
Hemolytic anemia
Neuromuscular dysfunction
2 conditions respond to Vitamin E treatment.
Fibrocystic breast disease
Intermittent claudication
