MCT - EXAM 3
Under neutral or alkaline pH iron is found in correct answers Ferric state: Fe3+
Ferrous in acidic
Most of iron in our body is found in correct answers Hb
Heme iron is found where? correct answers Meat
Poultry
Fish
Non heme iron is found where correct answers Nuts, breads, cereals, veggies
How is heme absorbed? correct answers There is a heme carrier protein that moves it
directly into the cell, it then is oxidated and Fe leaves heme
How deos non-heme iron enter the cell? correct answers Non-heme iron is ferric so we
need to convert it to ferrous via the DCYTB enzyme -> Enters via a divalent metal
transporter
Iron can be stored as ... in cells correct answers Ferritin
Hephaestin correct answers A copper-containing protein that oxidizes Fe2+ to Fe3+
once iron is transported across the basolateral membrane by ferroportin.
*Fe3+ is needed to dock onto transferrin*
Hepcidin function correct answers binds toferroportin on enterocytes and stimulates the
degradation of ferroportin through lysosomes
When is hepcidin high? correct answers When iron is high
Hepcidin deficiency can lead to? correct answers Hemochromatosis
Cells take up iron through which mechanism? correct answers Receptor-mediated
endocytosis
The endosome for iron uptake contains correct answers Two ferritin (4 Fe2+)
DMT1
Proton pump
Acidic environment
, Iron is stored majorly in the correct answers Liver as ferritin
Amorphous iron deposits are called correct answers hemosiderin
How are transferrin and DMT1 regulated? correct answers High iron binds to IREBPS
prevents its association with IRES -> mRNA degradation -> Decrease syn of transferrin
receptor and DMT1 *3' end*
How are ALAS and ferritin regulated correct answers High iron binds to IREBPs
prevents its association with IRES and increase the synthesis of these products,
permitting iron storage. *5' end*
Fenton reaction correct answers Fe2+ + H2O2 --> Fe3+ + OH- + OH.
Hereditary hemochromotosis is iron overload is seen typically when patients have an
inheritedm mutation in... correct answers HFE, this helps regulate hepcidin protein
expression.
Mutated HFe is trapped and can't signal activation of Hepcidin
HFE also blocks TFR and transferrin docking
Hemochromatosis leads to correct answers "Bronze diabetes" and Cirrhosis
Iron deficency anemia can be caused by drugs that reduce iron uptake such as correct
answers protein pump inhibitros like omeprazole
Pica correct answers compulsive eating of nonnutritive substances such as clay or ice
Clinical signs of anemia include correct answers Atrophic glossitis
Angular chelitis
Spoon nails - Koilonychia
Ways to treat iron deficent-anemia include correct answers FeSO4
Vit. C
Transfusion iron therapy
If iron intake is high but the individuals MCV is low still, what issues may they have?
correct answers Cu-deficency
If ceruloplasmic activity/ferroxidase activity is lost - this leads to correct answers iron
overload -> hemosiderosis
Describe Cu ATPase2 correct answers It's main function is to supply Cu to
ceruloplasmin however if liver levels of Cu get too high it transfers Cu for elimination to
bile
Under neutral or alkaline pH iron is found in correct answers Ferric state: Fe3+
Ferrous in acidic
Most of iron in our body is found in correct answers Hb
Heme iron is found where? correct answers Meat
Poultry
Fish
Non heme iron is found where correct answers Nuts, breads, cereals, veggies
How is heme absorbed? correct answers There is a heme carrier protein that moves it
directly into the cell, it then is oxidated and Fe leaves heme
How deos non-heme iron enter the cell? correct answers Non-heme iron is ferric so we
need to convert it to ferrous via the DCYTB enzyme -> Enters via a divalent metal
transporter
Iron can be stored as ... in cells correct answers Ferritin
Hephaestin correct answers A copper-containing protein that oxidizes Fe2+ to Fe3+
once iron is transported across the basolateral membrane by ferroportin.
*Fe3+ is needed to dock onto transferrin*
Hepcidin function correct answers binds toferroportin on enterocytes and stimulates the
degradation of ferroportin through lysosomes
When is hepcidin high? correct answers When iron is high
Hepcidin deficiency can lead to? correct answers Hemochromatosis
Cells take up iron through which mechanism? correct answers Receptor-mediated
endocytosis
The endosome for iron uptake contains correct answers Two ferritin (4 Fe2+)
DMT1
Proton pump
Acidic environment
, Iron is stored majorly in the correct answers Liver as ferritin
Amorphous iron deposits are called correct answers hemosiderin
How are transferrin and DMT1 regulated? correct answers High iron binds to IREBPS
prevents its association with IRES -> mRNA degradation -> Decrease syn of transferrin
receptor and DMT1 *3' end*
How are ALAS and ferritin regulated correct answers High iron binds to IREBPs
prevents its association with IRES and increase the synthesis of these products,
permitting iron storage. *5' end*
Fenton reaction correct answers Fe2+ + H2O2 --> Fe3+ + OH- + OH.
Hereditary hemochromotosis is iron overload is seen typically when patients have an
inheritedm mutation in... correct answers HFE, this helps regulate hepcidin protein
expression.
Mutated HFe is trapped and can't signal activation of Hepcidin
HFE also blocks TFR and transferrin docking
Hemochromatosis leads to correct answers "Bronze diabetes" and Cirrhosis
Iron deficency anemia can be caused by drugs that reduce iron uptake such as correct
answers protein pump inhibitros like omeprazole
Pica correct answers compulsive eating of nonnutritive substances such as clay or ice
Clinical signs of anemia include correct answers Atrophic glossitis
Angular chelitis
Spoon nails - Koilonychia
Ways to treat iron deficent-anemia include correct answers FeSO4
Vit. C
Transfusion iron therapy
If iron intake is high but the individuals MCV is low still, what issues may they have?
correct answers Cu-deficency
If ceruloplasmic activity/ferroxidase activity is lost - this leads to correct answers iron
overload -> hemosiderosis
Describe Cu ATPase2 correct answers It's main function is to supply Cu to
ceruloplasmin however if liver levels of Cu get too high it transfers Cu for elimination to
bile
