Final - Copper Flashcards
What are the sources of copper?
Depends on the origin of the soil
The richest sources are organ meats
Also dependent on food production, preparation and handling
What are the dietary factors that enhance the absorption of copper?
Amino acids - his, cys, met
Organic acids - citric, gluconic, lactic, acetic and malic
What inhibits the absorption of copper?
phytates zinc iron molybdenum calcium and phosphorus excessive antacid consumption
What does copper act as a cofactor for?
superoxide dismutase (antioxidant defense) ceruloplasmin (Fe metabolism)
What populations does copper deficiency occur in?
Infants recovering from malnutrition
Premature and low-birth weight infants fed milk diets
Patients recovering from prolonged TPN without added Cu
What are the symptoms of copper deficiency from low intake?
Anemia (reduces iron absorption and mobilization)
leukopenia, neutropenia
osteoporosis (infants and children)
Presumed rare
What are the functions of superoxide dismutase?
cytosolic and extracellular - catalyzes the removal (dismutation) of the superoxide radicals (O2-)
What are the functions of ceruloplasmin?
Responsible for Fe and Mn oxidation
Modulates the inflammatory response; levels increase during infection/inflammation
What are the functions of copper?
Mitochondrial function - cytochrome c oxidase
-terminal oxidative step in electron transport; Cu is oxidized allowing ATP production
Neurological function - dopamine monooxygenase (norepinephrine)
-converts dopamine to norepinephrine; Cu is oxidized (vit C)
Hair/skin/bones - lysyl oxidase
- cross links connective tissue proteins (bones, blood vessels etc) like collagen & elastin (stabilizes the extracellular matrix
- catalyzes the removal of an amino group of lysyl and hydroxylysyl residues of collagen and elastin; Cu is oxidized
What is copper deficiency from mutations called?
Menkes disease - mutations in Atp7A
What are the symptoms of menkes disease?
Menkes disease:
mental retardation, psyhomotor retardation
Abnormal hair (short, broken, twisted scalp hair):lysyl oxidase
Loss of pigmentation
poor weight gain, hyothermia
scurvy like changes in bone
parenteral Cu does not improve brain function, nor does it slow down the progression of the disease (problem is with the transportation)
Fatal by the age of 3
What are the symptoms of copper toxicity?
Neurological disorders chronic liver disease renal damage copper in urine deposition of Cu in the cornea
What is copper toxicity called?
Wilson’s disease - mutations in atp7B
What causes copper toxicity?
genetic defect in Cu storage; absorption is normal/biliary Cu excretion is limited
How is copper toxcity treated?
treated with chelation agents (D-penicillamine) and high zinc
