Minerals - Cu, Se, Cr, I, Mn Flashcards
Do acidic mediums increase or decrease copper absorption?
INCREASE - Gastric acid seems to enhance Cu absorption.
Hark, p. 76
Copper plays an essential role in the production of ___, ___ and ___ pigment (melanin).
Skin, hair and eye pigment
Hark, p. 76
Copper absorption is decreased by:
a. calcium
b. phytates
c. fiber
d. zinc
e. a and d
f. all of the above
e. all of the above
Hark, p. 76
Copper has 2 main forms: _____ (Cu²⁺) and _____ (Cu⁺). Copper’s ability to switch between these oxidation states make it important for redox reactions + scavenging free radicals by readily accepting and donating free radicals.
a. cupric and cuprous
b. ceruloic and cerulous
c. copric anc coprous
a. Cupric (Cu²⁺ = mostly found in the body) and cuprous (Cu⁺)
A key function of copper is protecting cells from from oxygen damage - it does this as a component of antioxidant enzymes such as ______ _______, an antioxidant that makes radicals less reactive by converting O₂⁻ > H₂O₂.
a. superoxide dismutase
b. glutathione
c. pycnogenol
d. coenzyme Q-10
a. superoxide dismutase (SOD)
Copper’s role in the synthesis of _____ tissue is critical for the development of healthy bones, teeth and vascular structures.
a. connective
b. epithelial
c. muscle
d. nervous
Connective tissue
Hark, p. 76
Copper is necessary for maintenance of the ____ ____ surrounding nerve fibers.
Myelin sheath
Hark, p. 76
Most copper is excreted in ____, and a small amount is excreted in _____.
a. urine; bile
b. bile; urine
c. urine; sweat
d. sweat; urine
b. bile; urine
https: //ods.od.nih.gov/factsheets/Copper-HealthProfessional/
Copper levels in the body are tightly regulated via copper absorption from the _____ ______ and copper release by the _____ into bile to provide protection from copper deficiency and toxicity.
Small intestine (mostly duodenum); liver.
High copper intake = copper is sequestered in metallothionein (metal-binding proteins) within enterocytes & increased excretion via bile
Low copper intake = intestinal absorption increases
Only small amounts of copper are typically stored in the body - of this, almost two-thirds of the body’s copper is located in:
a. skeleton and muscle
b. liver
c. enterocytes
d. red blood cells
a. skeleton and muscle
https: //ods.od.nih.gov/factsheets/Copper-HealthProfessional/
Copper is a cofactor for several enzymes, known as ________ involved in energy production, iron metabolism, neuropeptide activation, connective tissue synthesis, neurotransmitter synthesis and regulation of gene expression.
cuproenzymes
Energy production - copper needed for the electron transport chain
Iron metabolism - oxidizes Fe²⁺ to Fe³⁺ (req. for transport via transferrin) & involved in heme synthesis
Connective tissue synthesis – req. to cross-link collagen + elastin; involved in bone mineralization
CNS function – involved in neurotransmitter synthesis + metabolism; req. for synthesis + maintenance of myelin
Regulation of gene expression – Cu-dependent transcription factors (regulates transcription of certain genes)
https://ods.od.nih.gov/factsheets/Copper-HealthProfessional/
One abundant cuproenzyme is ________, which plays a role in iron metabolism and carries more than 95% of the total copper in healthy human plasma.
a. transferrin
b. hephaestin
c. hepcidin
d. ceruloplasmin
d. ceruloplasmin - the major copper-binding protein synthesized by the liver.
https: //ods.od.nih.gov/factsheets/Copper-HealthProfessional/
Copper is needed for the metabolism of ______ required in the functioning of the nervous system
a. catecholamines
b. acetylcholine
c. peptides
d. purines
a. catecholamines
Hark, p. 76
Although rare, copper deficiency can be acquired or inherited, and can occur in:
a. malnourished infants
b. premature infants
c. malabsorption syndromes (i.e. celiac disease)
d. Menke’s syndrome
e. excessive zinc intake
f. all of the above
f. all of the above
Other conditions/individuals with increased risk of Cu deficiency = prolonged diarrhea (infants), parenteral nutrition, cystic firbrosis.
High supplemental zinc intakes of 50 mg/day or more for extended periods of time may result in copper deficiency.
Menke’s syndrome = a rare, X-linked (more common in men), recessive disorder of copper homeostasis resulting in poor distribution of copper to the body’s cells. Primarily affects male infants. Copper accumulates in some tissues, such as the small intestine and kidneys, while the brain and other tissues have unusually low levels of copper. Symptoms = failure to thrive, impaired cognitive development, aortic aneurysms, seizures, poor muscle tone, weak bones and unusually kinky and/or colorless/steel-colored hair. Most individuals with Menkes disease die by age 3 years if untreated (Daily copper injections may improve outcome if given within days after birth; but since newborn screening for this disorder is not available, and early detection is infrequent because clinical signs are subtle in the beginning, the disease is rarely treated early enough to make a significant difference).
Hark, p. 76-77
https: //my.clevelandclinic.org/health/articles/6068-menkes-disease
https: //lpi.oregonstate.edu/mic/minerals/copper
The RDA for copper in adults 19+ is:
a. 500 mcg
b. 600 mcg
c. 800 mcg
d. 900 mcg
d. 900 mcg
Symptoms of copper deficiency include:
a. anemia
b. neutropenia (low white blood cell count)
c. loss of pigmentation in skin/hair
d. connective tissue damage
e. neurological symptoms
f. a and c
g. all of the above
f. all of the above
Other symptoms include: impaired growth and bone lesions/osteoporosis. Damage to connective tissues can result in lung damage or excessive bleeding.
Hark. p. 77
Top food sources of copper include:
a. organ meats, shellfish, nuts, seeds, whole grains, chocolate
b. milk, cheese, yogurt, beef, chicken, turkey
c. peppers, sweet potato, broccoli, Brussel sprouts, beans, legumes
a. organ meats, shellfish, nuts, seeds, whole grains, chocolate
Copper can also be high in hard water / houses with copper pipes. Running tap water for several seconds before using the water can reduce copper concentrations.
Kraus, p. 574
The TUL for copper in adults 19+ is:
a. 2,000 mcg/day
b. 5,000 mcg/day
c. 10,000 mcg/day
d. 15,000 mcg/day
c. 10,000 mcg/day
Hark, p. 77
True or false: Excessive copper intake or poisoning may occur with consumption of acidic beverages stored in containers made with copper.
True
Symptoms of copper toxicity include nausea, diarrhea, vomiting, abdominal pain, anemia, anuria, and, in extreme cases, liver damage, kidney failure, coma & death.
Hark, p. 77
Which genetic condition is most associated with copper toxicity?
a. Menke’s syndrome
b. Bartter syndrome
c. Paget’s disease
d. Wilson’s disease
d. Wilson’s disease. Copper toxicity is rare and usually associated with Wilson’s disease - an autosomal-recessive disorder associated with impaired biliary copper excretion, leading to copper overload via accumulation in various tissues (especially the liver, but also the brain, cornea and kidneys). Untreated, it can result in nervous system and liver damage. Low serum ceruloplasmin levels, elevated copper concentration in a liver biopsy, and high urinary copper excretion confirm the diagnosis. Patients can present with acute, fulminant (occurring suddenly with great severity), or chronic active hepatitis and neuropsychiatric symptoms. Copper chelating agents (to release copper from organs where it can be filtered out of the blood and excreted in urine) and zinc supplementation (to inhibit intestinal copper absorption and binding in the liver) is used to treat Wilson’s disease once it is diagnosed. Ongoing copper chelation is required to prevent relapses and liver failure; transplantation is needed corrects the metabolic defect (if Wilson’s disease isn’t dx until onset of liver failure, transplant is needed to survive). A low copper diet is no longer required, but may be helpful in initial treatment.
NFPE - Kayser-Fleischer rings in the eyes (dark yellowish ring encircling the iris, due to copper deposits in the cornea) are one sign of Wilson’s disease.
Kraus, p. 567
True or false? High dose zinc supplementation can deplete copper, and zinc supplements should be taken with copper to prevent copper depletion.
True (although for best absorption, separate supplementation).
Kraus, p. 202
To optimize absorption of copper supplementation, it’s best to supplement away from:
a. iron
b. alpha lipoic acid
c. vitamin C
d. zinc
e. a and d
f. all of the above
f. all of the above
Iron - competes for intestinal absorption; Cu req. for normal Fe metabolism + transport to bone marrow for erythropoiesis
ALA - can chelate Cu + incr. Cu urinary excretion
Vit C - can inhibit Cu absorption if supplementing with high doses (500-600mg/day+), administer separately
Zinc - high dose Zn can lead to Cu deficiency; high Zn also increases level of metallothionein, which has affinity for Cu (leads to decreased Cu absorption)
Molybdenum: high doses of Cu may lead to Mo deficiency + vice versa
Which drugs can interfere with copper absorption?
a. antacids
b. penicillamine
c. oral contraceptives
d. a & b
e. all of the above
d. a & b
High doses of antacids may interfere w/ absorption (gastric acid aids Cu absorption)
Penicillamine (used in chelation) binds to Cu and increases its elimination in Wilson disease – if taking this + no Wilson disease, may be increased need for Cu
True of false? Copper supplements may improve the effectiveness of vitamin D and calcium in improving bone density in post-menopausal women.
True
Hark, p. 77