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Updated: Jun 6, 2025
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Cultivating a Three-dimensional Reconstructed Human Epidermis at a Large Scale
Published on: May 28, 2021
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Constitutive HIF-1α Expression in the Epidermis Fuels Proliferation and Is Essential for Effective Barrier Formation
Julia Boix1, Jana Knuever2, Nadine Niehoff3
1Center for Physiology and Pathophysiology, Institute of Systems Physiology, University of Köln, Köln, Germany; Center for Molecular Medicine Cologne, University of Köln, Köln, Germany.
The Journal of Investigative Dermatology
|November 23, 2024
Summary
Hypoxia-inducible factor 1-alpha (HIF-1α) is crucial for skin cell proliferation and barrier function by promoting aerobic glycolysis. Its constitutive expression in keratinocytes supports energy and lipid synthesis, vital for skin health.
Area of Science:
- Cell Biology
- Dermatology
- Metabolism
Background:
- The epidermis is a highly proliferative tissue with significant energy demands.
- Keratinocytes require substantial adenosine triphosphate and cellular building blocks for rapid growth and function.
Purpose of the Study:
- To investigate the role of Hypoxia-inducible factor 1-alpha (HIF-1α) in epidermal metabolism and function.
- To understand how keratinocytes meet their high energy and biosynthetic demands.
Main Methods:
- Epidermal ablation of HIF-1α in mice with induced mitochondrial dysfunction.
- Analysis of proliferation, lethality, and barrier defects.
Main Results:
- Constitutive HIF-1α expression in keratinocytes supports aerobic glycolysis even under normal oxygen conditions.
- Epidermal HIF-1α is essential for keratinocyte proliferation and skin barrier formation.
- Combined HIF-1α ablation and mitochondrial dysfunction led to decreased proliferation and accelerated lethality due to barrier defects.
Conclusions:
- HIF-1α is indispensable for maintaining the high aerobic glycolytic flux in keratinocytes, supplying energy and essential lipids for proliferation and barrier integrity.
- Constitutive HIF-1α expression enables a Warburg-like metabolism in healthy, proliferative keratinocytes, akin to tumor cells.
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