Mind map
Iron Metabolism
Mind map: iron metabolism
Map content
Iron Metabolism
Reactions
- redox
- accept e-
- ferrous (Fe2+)
- donate e-
- ferric (Fe3+)
- physiology
- electron transport
- Fe-S clusters, cytochromes
- respiratory chain
- Fe-S clusters, cytochromes
- electron transport
- pathophys
- free Fe
- lipid peroxidation
- PUFAs
- atherogenesis
- lipid peroxidation
- free Fe
- accept e-
- Fenton
- free radical formation
- ROS
- H2O2
- ROS
- free iron
- injured tissue
- breakdown of heme
- free radical formation
- redox
Distribution
- major
- hemoglobin
- RBC
- 1800 mg
- RBC
- hemoglobin
- minor
- muscle fibers
- 300 mg
- liver
- 1000 mg
- macrophages
- 600 mg
- muscle fibers
- major
Transport/Storage
- plasma
- transferrin
- 30% saturated
- transferrin
- cell storage
- ferritin
- interact w/ ceruloplasmin or hephaestin
- binds transferrin
- transported
- binds transferrin
- interact w/ ceruloplasmin or hephaestin
- ferritin
- other binders
- neutrophils
- lactoferrrin
- tissue injury
- hemosiderin
- mitochondrial storage protein
- frataxin
- neutrophils
- plasma
Steps of Metabolism
- 1) intestinal absorption of ferrous
- stomach
- low pH
- reduce iron (III) --> (II)
- low pH
- intestines
- alkaline environment
- heme
- direct absorption
- mucosal cells
- iron dissociates
- free iron
- oxidized
- (II)-->(III)
- reduced again
- taken up by mucosal
- reduced again
- (II)-->(III)
- oxidized
- mucosal cells
- direct absorption
- heme
- alkaline environment
- transport across epithelium
- apical
- DMT1
- basolateral
- ferroportin
- requires hepaestin
- ferroportin
- apical
- regulation
- dietary regulator
- short term
- decrease DMT1
- stores regulator
- hepcidin
- responds to total body iron
- 25 aa peptide
- regulate export
- intestinal cells
- macrphages
- hepatocytes
- inactivates ferroportin
- induces internalization
- lysosomal degradation
- induces internalization
- synthesis regulation
- activates
- inflammation
- inhibits
- iron deficiency
- increased erythropoiesis
- hypoxia
- activates
- hepcidin
- erythropoietic regulator
- modulate reabsorption based on erythropoiesis requirements
- no reponse to iron
- modulate reabsorption based on erythropoiesis requirements
- dietary regulator
- stomach
- 3) cellular uptake and storage in ferritin and frataxin
- transferrin receptor
- uptake at PM
- di-ferric transferrin internalized
- endocytosis
- di-ferric transferrin internalized
- uptake at PM
- regulation
- IRP-1
- cytosolic aconitase
- RNA binding protein
- cells iron depleted
- cell ironreplet
- RNA binding protein
- senses iron depletion/oxidative stress
- activation
- binds 2 mRNAs
- ferritin IRE
- 5' untranslatable regioon
- inhibits translation
- 5' untranslatable regioon
- transferrin receptor
- 3' untranslatable region
- increases translation
- 3' untranslatable region
- ferritin IRE
- overall effect
- decrease ferritin synthesis
- increase transferrin receptor synthesis
- increase cellular uptake
- binds 2 mRNAs
- cytosolic aconitase
- IRP-1
- transferrin receptor
- 2) plasma transport by transferrin
- Fe (III) delivered to apo-transferrin
- transport to diff tissues
- binds 2 Fe (III) atoms
- from bone marrow
- transport to diff tissues
- Fe (III) delivered to apo-transferrin
- 1) intestinal absorption of ferrous
Nutrition
- dietary sources
- liver, red meat, eggs, whole grain, dried fruit, beans, drinking water, iron cooking pots
- SPINACH
- liver, red meat, eggs, whole grain, dried fruit, beans, drinking water, iron cooking pots
- absorption
- enhanced
- ascorbic acid, dietary protein, erythropoiesis, hypoxia, low stores
- inhibited
- oxalic acid, coffee, tea, bran, egg yolk, soybean products, calcium, polyphenols, excess metals, inflammation, achlorydria
- enhanced
- excretion
- limited capacity
- transferrin bound
- not excreted in kidney
- chelators
- excretable
- transferrin bound
- hemorrhage
- limited capacity
- dietary sources
Disease
- deficiency
- anemia
- impaired immune resonse
- initial
- no symptoms
- diagnosis
- < 20% transferrin sat
- treatment
- ferrous sulfate
- packed RBCs
- iron overload
- acute iron poisoning
- hypotension
- metablolic acidosis
- coma
- chronic iron overload
- patients who receive transfusions
- congenital anemias
- patients who receive transfusions
- ineffective erythropoiesis
- increased iron absorption
- certain anemias
- destroy erythrocytes in bone marrow
- signal erythroid regulator
- increased iron absorption
- signal erythroid regulator
- destroy erythrocytes in bone marrow
- certain anemias
- conditions
- thalassemias
- sideroblastic anemias
- increased iron absorption
- acute iron poisoning
- Hereditary Hemochromatosis HH)
- iron overload
- mutation
- HFE gene
- caucasian
- carrier = 1/10
- caucasian
- TFR2
- HJV
- HFE gene
- absorb/store too efficiently
- symptoms
- iron accumulation
- oxidative damage in these tissues
- liver
- cirrhosis
- heart
- cardiomyopathy
- pancreas
- DM
- skin
- pigmentation
- joints
- polyarthropathy
- gonads
- hypogonadotrophic hypogonadism
- liver
- oxidative damage in these tissues
- iron accumulation
- treatment
- phlebotomy
- chelators
- before organ damage
- phlebotomy
- Anemia of chronic disease (ACD)
- impaired utilization of iron
- no deficiency/excess
- defect
- blockage
- stores --> erythroid precursors
- blockage
- treatment
- underlying cause
- disease leads to ACD
- chronic infections
- inflammatory bowel disease
- neoplasia
- autoimmune disease
- mechanism
- inflammatory cytokines
- IL6
- Hepcidin upregulated
- inflammatory cytokines
- impaired utilization of iron
- deficiency
Information
- Description
- Biochemistry Mind Map on Iron Metabolism, created by hardinbc on 02/05/2013.
- Created by
- hardinbc
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