Heme oxygenase-1 increases endothelial progenitor cells
Ben J Wu1, Robyn G Midwinter, Carlos Cassano
1Centre for Vascular Research, School of Medical Sciences and Bosch Institute, Faculty of Medicine, University of Sydney, NSW 2006, Australia.
Arteriosclerosis, Thrombosis, and Vascular Biology
|June 23, 2009
Summary
Heme oxygenase-1 (HO-1) enhances vascular repair by increasing endothelial progenitor cells (EPCs) from bone marrow. This promotes reendothelialization, crucial for healing atherosclerotic disease.
Area of Science:
- Cardiovascular Biology
- Vascular Biology
- Regenerative Medicine
Background:
- Heme oxygenase-1 (HO-1) plays a protective role in atherosclerotic disease.
- Endothelial progenitor cells (EPCs) are vital for reendothelialization and vascular repair.
Purpose of the Study:
- To investigate the role of HO-1 in the function and mobilization of bone marrow and circulating EPCs.
- To determine if HO-1 induction influences EPC contribution to reendothelialization.
Main Methods:
- Utilized a rabbit model of aortic balloon injury to assess reendothelialization.
- Administered HO-1 inducers and inhibitors in animal models (rabbits and mice).
- Quantified circulating progenitor cells, bone marrow progenitor cell colony formation, and EPC differentiation.
Main Results:
- Pharmacological HO-1 induction improved reendothelialization in injured rabbit aortas.
- HO-1 induction increased circulating progenitor cells and enhanced bone marrow progenitor colony formation.
- HO-1 deficiency in mice reduced endothelial colony-forming cells and impaired HO-1 inducer effects.
Conclusions:
- HO-1 induction promotes vascular repair by increasing the number and function of circulating EPCs.
- EPCs mobilized from the bone marrow contribute to HO-1-mediated reendothelialization.
- Targeting HO-1 may represent a therapeutic strategy for enhancing vascular healing.
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