Minerals Flashcards
What are folate’s functions?
Precursor of THF; coenzyme involved in generating DNA precursors and protein synthesis
What are three defects associated with folate deficiency?
Neural tube defects in newborns; macrocytic anemia; hyperhomocysteinemia (cardiovascular risk)
Who is susceptible to folate deficiency?
Pregnant women; elderly (absorption problem); alcoholics; patients with long-term drug treatments; people with genetic polymorphisms in folate metabolism
When is folate demand highest?
Pregnancy; lactation
What can lower risk of folate deficiency?
Grain products enriched with folate; folate supplements
What is cobalamin involved in?
Methionine synthesis; conversion of methylmalonyl CoA to succinyl CoA; folate metabolism!!
What is the main consequence of B12 deficiency? How is it different from B9 deficiency?
It is also macrocytic anemia, but you also see demyelination
Who is susceptible to B12 deficiency?
Elderly, people with malabsorption diseases, vegetarians
What does B12 contain? How does it get absorbed?
A cobalt; it must be released from protein by acid hydrolysis and be absorbed in ileum by combining with intrinsic factor
With the folate trap, what two things can you not make for DNA synthesis, contributing to the megaloblastic anemia with B12 deficiency?
dTMP and purine ring, so not enough DNA to continue replication as a RBC would normally get smaller
What does pernicious anemia refer to?
A B12-deficient anemia arising from lack of intrinsic factor
What four macrominerals does Kane cover?
Ca, P, S, Mg
What is calcium involved in?
Major component of Bone; Signaling, Coagulation (localize clots), Muscle contraction, Neurotransmission
Calcium deficiency is characterized by what?
Mild: muscle cramps, osteoporosis; severe: rickets
Who is susceptible to Ca deficiency?
Elderly, adult women, children
Where is most of calcium found? What is the basic mineral component?
98% in bone and teeth; hydroxyapatite
What is the body’s calcium reservoir?
Bone, if serum levels are insufficient
What do low serum calcium levels enhance?
Intestinal absorption and bone resorption
To prevent osteoporosis, what do people need regarding calcium intake?
Need to take in calcium when bone is reaching maximum density
What does Mg do?
Essential for many ATPases; present at high levels in bone
What is Mg deficiency related to?
Weakness, tremors, cardiac arrhythmia
Who is susceptible to Mg deficiency?
Alcoholics; diuretics, or severe vomiting and diarrhea
What does phosphorous do?
Mostly phosphates; major component of bone as hydroxyapatite; seen in membrane lipids and nucleic acids; required in energy producing reactions
What would you see in a P deficiency, if at all?
Rickets, muscle weakness and breakdown, seizure
What is iron involved in?
O2/CO2 transport in Hg; oxphos; cofactor in nonheme iron proteins and cytochromes
What are iron deficiencies associated with?
Microcytic hypochromic anemia; decreased immunity
Who are susceptible groups for iron deficiencies?
Children, menstruating women, pregnant women, elderly
What promotes reduction of Fe3 to Fe2?
Vitamin C (otherwise, causes a mild anemia)
What are the two major barriers to Fe absorption?
Release of Fe3 from the food; and reduction of Fe3 to Fe2
What signals Fe2 sufficiency in the blood?
Hepcidin, which prevents excess Fe2 export from intestinal mucosal cells
What does one see with iron-deficient anemia?
Microcytic (small, pale RBC’s); less Hg produced, and RBCs undergo more cell divisions
Patient symptoms of iron-deficient anemia?
Fatigue, pallor, weakness, dizziness
What can long term iron toxicity lead to? Which organs can be affected? What can compromised mito function lead to?
Hemochromatosis; liver, pancreatic, cardiac function, mitochondria; lactic acidosis
What does acute iron toxicity lead to?
Iron overdose in children (consumption of adult iron supplements?
What does copper aid with?
Assists Fe absorption through ceruloplasmin; cofactor for enzymes involved in collagen synthesis, FA metabolism, elimination of ROS
What would you see with copper deficiency?
Anemia, hypercholesterolemia, large arteries fragile, bone demineralization, demyelination
Who is susceptible to Cu deficiency?
Menkes’ syndrome patients; consumers or excessive zinc
Where does Menkes syndrome come from?
Mutations in Cu transpoter ATP7 A
How does Wilson’s disease come about?
Mutations in ATP7B, leading to copper overload; severe liver and NS symptoms
What does Zn do?
Cofactor for many metalloenzymes; plays structural role in many proteins
What are Zn deficiencies associated with?
Poor wound healing, dermatitis, poor sexual and developmental growth, and poor taste acuity
Who is susceptible to Zn deficiencies?
Elderly, those with malabsorption or kidney disease, alcoholics
What does chromium do? What is deficiency associated with?
Part of chromomodulin; facilitates insulin binding to receptor; impaired glucose tolerance
Who is susceptible to chromium deficiency?
Those with poor glucose tolerance
Iodine deficiency related to what?
Goiter; hyper- or hypothyroidism
What does selenium do?
Makes up antioxidant enzymes, like glutathione; makes up deiodinase enzymes
What is a selenium deficiency characteristic?
Keshan disease: cardiomyopathy and cretinism
Children most susceptible to…
Iron and calcium deficiency
Teenagers most susceptible to…
Ca, Mg, Vit A, C, B6
Women most susceptible to…
Fe, Ca, Mg, B6, Folate
Elderly most susceptible to…
Vit B6, B12, D, Zn, Cr
Alcoholics most susceptible to…
particularly B6, folate, thiamine
