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Updated: Dec 12, 2025
09:43
Measurement of Heme Synthesis Levels in Mammalian Cells
Published on: July 9, 2015
12.4K
Heme Synthesis Inhibition Blocks Angiogenesis via Mitochondrial Dysfunction.
Trupti Shetty1, Kamakshi Sishtla2, Bomina Park1
1Eugene and Marilyn Glick Eye Institute, Department of Ophthalmology, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Pharmacology & Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
Iscience
|August 7, 2020
Summary
This study reveals how inhibiting heme synthesis impacts endothelial cell function and angiogenesis. Reduced heme levels disrupt mitochondria, causing oxidative stress and impairing blood vessel formation.
Area of Science:
- Mitochondrial biology
- Vascular biology
- Biochemistry
Background:
- The link between heme metabolism and angiogenesis is not well understood.
- Ferrochelatase (FECH) is crucial for the final step of heme synthesis in mitochondria.
- Previous work demonstrated FECH inhibition's antiangiogenic effects in endothelial cells and animal models.
Purpose of the Study:
- To elucidate the mechanism by which FECH and heme influence endothelial cell function.
- To investigate the impact of heme depletion on mitochondrial integrity and function in endothelial cells.
Main Methods:
- Inhibition of ferrochelatase (FECH) in human retinal microvascular endothelial cells (HRECs).
- Assessment of mitochondrial morphology, mass, oxidative stress, and oxidative phosphorylation.
- Evaluation of mitochondrial Complex IV activity.
- Heme supplementation as a rescue experiment.
Main Results:
- FECH inhibition led to mitochondrial dysfunction, altered mitochondrial shape and mass, and increased oxidative stress in HRECs.
- Oxidative phosphorylation and Complex IV activity were significantly decreased following heme depletion in HRECs and ex vivo murine retina.
- Heme supplementation partially reversed the observed cellular and functional defects.
Conclusions:
- Mitochondrial heme metabolism is intrinsically linked to endothelial cell function and angiogenesis.
- FECH-mediated heme synthesis plays a critical role in maintaining mitochondrial integrity and function essential for angiogenesis.
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