11-21 L4 Iron metabolism & Iron disorders Flashcards
Define two sources of iron and there bioavialability
- heme (15-30%)
- nonheme (5-15%)
Fe is absorbered into the enterocyte by what trasporter?
what 2 things inhibits this transport (this inhibition molecule is found in what?)
- DMT1 (H+ 2ndary active transporter
- (sreving Fe2 but not Fe3)
- Inhibited by
- Cd (candium)
- high concentration of Ca
Name 2 promoting factors of iron
- Heme
- Ascorbic acid
What mediates cellular iron export?
what hormone controls it?
- ferroprotin mediates cellular iron export
- hepcidin
What does hepcidin do?
(RAP)
- R: decreases fe recycling (macrophages)
- A: decreases intestinal Fe absorption
- P: decreased ciruculating Fe2Tf pool
Name 2 iron-refractory iron deficiency anemia
- Mutations in matriptase
- Iron-refractory iron-deficiency anemia
Hereditary hemochromatosis type 1 (iron overload)
what is the mutation
- mutation in HFE
Hereditary hemochromatosis type 4 (iron overload)
what is the mutation
- Ferroprotin
- Autosomal dominant
What is teh cause of iron toxicity?
what type of general damage does it do?
- by-product of iron oxidation (Fe2–>Fe3)
- causes lipid peroxidation, damage to DNA enzymes, polysaccharides
what is the mainstay treatment of Hereditary iron deficiency?
- repeated phleobotomy
What is the leading cause of death in Beta-thalaseemia patients?
treatment?
- iron overload
- cardiomyopathy (iron overload)
iron chelators
how does IDA (iron deficiency anemia) appear?
microcytic hypochromic anemia
Iron deficiency beings with what?
how do we treat it?
- beings with depletino of Fe stores
- once you see hypochromic microcytic that means you have been iron def for awhile
- Treatment
- oral Fe supplementation (parenteral Fe)
