Vitamins Flashcards
What are the lipid soluble vitamins?
ADKE
What are the water soluble vitamins?
BC
What are the functions of Vit A?
Visual cycle-Rhodopsin and cone opsins
Retinoic acid
antioxidant
What occurs with Vit A deficiency?
Night blindness (early) Xerophthalmia (advanced)--thickening of the conjunctiva---leading to keratomalacia (destruction of the eye) follicular hyperkeratosis anemia poor growth in children increased risk of infection and cancer
What occurs with Vit A toxicity?
Vit A accummulates in the liver
Sym–nausea/diarrhea/bone pain/scaly skin/orange skin
What are the functions of Vit D?
maintaining bone
Ca homeostasis
acts as hormone
What occurs with Vit D deficiency?
Rickets–children—-soft, pliable bones
osteomalacia–adults—loss of minerals from preexisting bone
increased susceptibility to breast and other cancers/metabolic syndrome/diabetes/infection
What occurs with Vit D toxicity?
Rare—high serum levels of calcium and bone loss
What are the functions of Vit K?
localization of enzymes required for blood clotting
helps catalyze addition of g-carboxyglutamate to clotting enzymes
What occurs with Vit K deficiency? Who are susceptible?
easy bruising/bleeding/hemorrhage
Newborn infants–lack intestinal bac to make Vit K and are susceptible to brain bleeds
Long term antibiotic pts–can kill intestinal bac
elderly
What does Warfarin block in blood clotting cascade?
VKORC1–which is responsible to provide a continuous source of the KH2 form of Vit K
What are the functions of Vit E?
Antioxidant–scavenger of free radicals
protect membrane from damage–located in ALL cell and organelle membranes—–a-tocopherol suited to intercepting free radicals and preventing a chain reaction of lipid destruction
prevents oxidation of LDL
Family of structures—tocopherols and tocotrienols
What occurs with Vit E deficiency? Who are susceptible?
Cardiovascular Dz
Neurological symptoms
Pts with severe prolonged defects in absorption/genetic defects
What are the functions of Vit C (ascorbic acid)?
Cofactor for oxidases involved in collagen formation–proline–>lysine hydroxylation
Required for synthesis of steroids in stress response
Aids absorption of iron
antioxidant
What occurs with Vit C deficiency? Who are susceptible?
Mild- bruising/immunocompromise
severe- Scurvy–decreased wound healing/osteoporosis/hemorrhage (corkscrew & pinpoint) /anemia/fatigue
Ppl with poor diet and smokers
Pts being treated with long-term aspirin/oral contraceptives/corticosteroids
What are the energy releasing B-complex vitamins?
Thiamine (B1) Riboflavin (B2) Niacin (B3) Biotin (B7) Pantothenic Acid (B5) Pyridoxine (B6)
What are the hematopoietic B-complex vitamins?
Folate (B9)
Cobalamin (B12)
What are common effects of deficiencies in energy-releasing B vits?
Syms in rapidly growing tissues first–skin/GI
Nervous system also affected—peripheral neuropathy/depression/confusion/lack of coordination/malaise
What are the functions of Thiamine (B1)?
Required cofactor for several enzymes in cellular energy metabolism
Critical in nervous system
What occurs in Thiamine (B1) deficiency?
Mild- GI symptoms/depression/fatigue
Moderate- Wernicke-korsakoff syndrome—chronic alcoholics—mental distrubance/unsteady gate/uncoordinated eye movement/sometimes CHF
Severe- BeriBeri—-extreme muscle weakness/poly-neuropathy/heart failure—rice dependent diet
Thiamine is not stored in the body and deficiencies can occur quickly when the diet is inadequate
What are the functions of Riboflavin (B2)?
Precursor of FAD and FMN–key coenzymes for redox reactions involved in energy metabolism
What occurs in Riboflavin(B2) deficiency?
Ariboflavinosis–rash around nose/inflam of mouth and tongue/buring and itchy eyes/light sensitivity
What are the functions of Niacin(B3)? And who is it given to for supplementation?
Precursor of NAD and NADP—coenzymes important in redox reactions of energy metabolism
Pts with hypercholesterolemia/hypertriglyceridemia
What occurs in Niacin(B3) deficiency? who’s at risk?
Pellagra–dermatitis(RED NECK)/diarrhea/mental symptoms
–treated with tryptophan/niacin supplementation
Pts with corn/millet based diets