Abstract
Heme exists as a prosthetic group in numerous enzymes and other hemeproteins, with which it is involved in oxygen transport and storage, electron transfer reactions, detoxification of xenobiotics, signal transduction, and transcriptional, translational, and microRNA gene regulation. Heme biosynthesis comprises multistep enzymatic reactions in both the mitochondria and the cytosol, whereas heme catabolism by heme oxygenase recycles iron and produces carbon monoxide and bilirubin. Excess heme is potent and toxic and has the propensity to activate oxidative stress and inflammatory processes. Haptoglobin, hemopexin, and albumin scavenge and sequester excess toxic hemoglobin and heme from the circulation. Biogenesis, biodegradation, and heme trafficking are regulated to maintain homeostasis.
Original language | English |
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Title of host publication | Encyclopedia of Food and Health |
Publisher | Elsevier Inc. |
Pages | 452-460 |
Number of pages | 9 |
ISBN (Electronic) | 9780123849533 |
ISBN (Print) | 9780123849472 |
DOIs | |
Publication status | Published - 22 Sept 2015 |
Keywords
- ABCG2
- Anemia
- Erythrophagocytosis
- Erythropoiesis
- FLVCR
- Haptoglobin
- Heme
- Heme oxygenase
- Hemeproteins
- Hemoglobin
- Hemopexin
- HRG1
- Porphyria
- δ-Aminolevulinate