Iron physiology.شرح بالعربى
Iron deficiency anemia ,causes and pathogenesis.
Link to share this lecture:
https://www.youtube.com/watch?v=tCoOgFXNVF4&list=UUtC5uHEzvqjN3hhT2XsGr8w
Contents:
1-Iron physiology
2-Definition of anemia
3-Causes of iron deficiency anemia
4-Clinical presentation of iron –deficiency anemia
1-Much of the iron in the human body is in circulating red cells,. which contain 1 mg of iron per 1 mL of packed cells
2-Iron is stored in the form of ferritin or hemosiderin. Smaller amounts of iron are present in myoglobin and in many enzymes
3-. Because little iron is lost from the body under normal
circumstances, the iron content of the body is regulated by modulating iron absorption.
4-Separate pathways exist for the absorption of heme and inorganic iron.
.5- Iron absorption increases in the presence of iron deficiency and it decreases when there is iron overload
.
Link for sharing this lecture:
https://www.youtube.com/watch?v=fROa1-ZBtaE&list=UUtC5uHEzvqjN3hhT2XsGr8w
Hepcidin
is an antimicrobial peptide ,created in the liver that retains weak antimicrobial activity.
Injection of synthetic hepcidin downregulates(decreases) iron absorption.
Hepcidin exerts its iron-regulatory effect by binding to ferroportin, a transmembrane iron-transport protein expressed both on intestinal mucosal cells and macrophages.
Once hepcidin has bound to ferroportin, the ferroportin is internalized and undergoes proteolysis.
With membrane ferroportin depleted, iron cannot be transported from the mucosal cell or from the macrophage into the plasma.
This results in decreased iron absorption from the gastrointestinal tract and a fall in the plasma iron level.
Like other antimicrobial peptides, hepcidin production is stimulated by inflammatory cytokines such as interleukin (IL)-1 and IL-6, and it is likely that overproduction of hepcidin is one of the factors in the pathogenesis of the anemia of chronic inflammation
Anaemia is present when there is a decrease in haemoglobin in the blood below the reference level for the age and sex of the individual
3-Causes of iron deficiency anemia
1-Blood loss :the commonest cause
(GIT blood loss resulting from parasites such as hookworm infestation,piles, heavy menstruation, use of NSAIDS)
2- Poor intake
3- Decreased absorption(e.g.Post-gastrectomy,malabsorption syndrome)
4- Increased demands,e.g.Growth and pregnancy
The symptoms of anaemia are non-specific and include
1-Breathlessness, fatigue, headaches, palpitations and faintness.
2-Anaemia exacerbates cardiorespiratory problems, especially in the elderly. For example, angina or intermittent claudication may be precipitated by anaemia
Iron deficiency anemia ,causes and pathogenesis.
Link to share this lecture:
https://www.youtube.com/watch?v=tCoOgFXNVF4&list=UUtC5uHEzvqjN3hhT2XsGr8w
Contents:
1-Iron physiology
2-Definition of anemia
3-Causes of iron deficiency anemia
4-Clinical presentation of iron –deficiency anemia
1-Much of the iron in the human body is in circulating red cells,. which contain 1 mg of iron per 1 mL of packed cells
2-Iron is stored in the form of ferritin or hemosiderin. Smaller amounts of iron are present in myoglobin and in many enzymes
3-. Because little iron is lost from the body under normal
circumstances, the iron content of the body is regulated by modulating iron absorption.
4-Separate pathways exist for the absorption of heme and inorganic iron.
.5- Iron absorption increases in the presence of iron deficiency and it decreases when there is iron overload
.
Link for sharing this lecture:
https://www.youtube.com/watch?v=fROa1-ZBtaE&list=UUtC5uHEzvqjN3hhT2XsGr8w
Hepcidin
is an antimicrobial peptide ,created in the liver that retains weak antimicrobial activity.
Injection of synthetic hepcidin downregulates(decreases) iron absorption.
Hepcidin exerts its iron-regulatory effect by binding to ferroportin, a transmembrane iron-transport protein expressed both on intestinal mucosal cells and macrophages.
Once hepcidin has bound to ferroportin, the ferroportin is internalized and undergoes proteolysis.
With membrane ferroportin depleted, iron cannot be transported from the mucosal cell or from the macrophage into the plasma.
This results in decreased iron absorption from the gastrointestinal tract and a fall in the plasma iron level.
Like other antimicrobial peptides, hepcidin production is stimulated by inflammatory cytokines such as interleukin (IL)-1 and IL-6, and it is likely that overproduction of hepcidin is one of the factors in the pathogenesis of the anemia of chronic inflammation
Anaemia is present when there is a decrease in haemoglobin in the blood below the reference level for the age and sex of the individual
3-Causes of iron deficiency anemia
1-Blood loss :the commonest cause
(GIT blood loss resulting from parasites such as hookworm infestation,piles, heavy menstruation, use of NSAIDS)
2- Poor intake
3- Decreased absorption(e.g.Post-gastrectomy,malabsorption syndrome)
4- Increased demands,e.g.Growth and pregnancy
The symptoms of anaemia are non-specific and include
1-Breathlessness, fatigue, headaches, palpitations and faintness.
2-Anaemia exacerbates cardiorespiratory problems, especially in the elderly. For example, angina or intermittent claudication may be precipitated by anaemia
Category
📚
Learning