Iron Flashcards
State where iron is when it’s active.
Haemoglobin, myoglobin and enzyme systems e.g. cytochromes.
State the stores of iron
Ferritin (soluble), mainly in the liver
Haemosiderin in macrophages
Describe the difference between haem and non-haem iron.
Haem - best absorbed by the gut. Mostly found in meats. Ferrous iron (Fe2+)
Non-haem - mostly in veg/grains. Ferrick iron (Fe3+). Reduced to Fe2+ before transportation across the gut epithelium.
What receptor in enterocytes allows iron to be transported into the blood?
Ferroportin
What protein does iron bind to in blood for transport?
Transferrin
What vitamin increases absorption of iron?
C
What substances can decrease absorption of iron?
Tea, chapatis, antacids
How do red blood cells take up iron?
Iron-transferrin complex binds to transferrin receptor
What does iron absorption depend on?
Diet, stores and erythropoiesis
Describe the function of hepcidin and where it is produced.
Liver.
Prevents iron release from macrophages and degrades ferroportin.
Synthesis is increased in iron overload.
Synthesis decreased by high erthropoietic activity.
Describe functional iron deficiency
Have plenty of iron in the body but is trapped in stored.
Describe the most common cause of anaemia of chronic disease
High hepcidin due to inflammatory cytokines
Give some symptoms of anaemia.
Tired all the time, lethargy, pallor, decreased exercise tolerance, heart failure, palpatations, shortness of breath.
Can cause oesophageal webs and spoon-shaped nails when far progressed.
Give the results of blood tests that you would have if you were diagnosing someone with anaemia.
Low mean cell volume due to small RBC
Microcytic, hypochromia, pencil cells
Low serum ferritin/iron/percentage transferrin
Describe symptoms of haemochromatosis
Cirrosis, liver failure, diabetes hypogonadism, cardiomyopathy, arthropathy, skin pigmentation. Depends on deposition.
