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Updated: Jul 12, 2026
09:43
Measurement of Heme Synthesis Levels in Mammalian Cells
Published on: July 9, 2015
[Heme-iron in the human body]
József Balla1, György Balla, Béla Lakatos
1Debreceni Egyetem, Orvos- és Egészségtudományi Centrum I. Belgyógyászati Klinika, Szülészeti Klinika, Nefrológiai Tanszék, Neonatológiai Tanszék Debrecen.
Orvosi Hetilap
|September 4, 2007
Summary
Iron absorption is tightly regulated to maintain balance. This review summarizes how the body processes heme, a crucial iron source, from diet and its release during hemolysis.
Area of Science:
- Biochemistry
- Physiology
- Cell Biology
Context:
- Iron is vital for life but toxic in excess, necessitating strict absorption control.
- Heme iron from diet is a major source in some populations, absorbed by intestinal cells.
- Heme is also a component of essential proteins like hemoglobin.
Purpose:
- To review the metabolic pathways of heme in the human body.
- To elucidate heme absorption, degradation, and its role in iron homeostasis.
- To summarize heme's fate following dietary intake and intravascular hemolysis.
Summary:
- Dietary heme is absorbed by enterocytes, degraded by heme oxygenase, and released as transferrin-bound iron.
- Hemoglobin released during hemolysis binds haptoglobin, is internalized by macrophages, and heme is degraded.
- Oxidation of hemoglobin to methemoglobin promotes free heme release, which is cleared by hemopexin or lipoproteins, potentially causing cell damage.
Impact:
- Understanding heme metabolism is crucial for managing iron overload disorders.
- This review provides insights into cellular iron uptake and utilization mechanisms.
- Knowledge of heme's role in oxidative stress and cell damage informs therapeutic strategies.
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The resident phagocytic macrophages deal with these damaged cells by engulfing them and separating their globin and heme groups.
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